ArticlePDF Available

Subacromial impingement syndrome: a musculoskeletal condition or a clinical illusion?

Authors:

Abstract

Background: Subacromial impingement syndrome is considered by many to be the most common of the musculoskeletal conditions affecting the shoulder. It is based on a hypothesis that acromial irritation leads to external abrasion of the bursa and rotator cuff. Objectives: The aim of this paper is to review the evidence for the acromial irritation theory and in doing so challenge the rationale for subacromial decompression. Major findings: There is a body of evidence that suggests there is a lack of concordance regarding (i) the area of tendon pathology and acromial irritation, (ii) the shape of the acromion and symptoms, (iii) the proposal that irritation leads to the development of tendinitis and bursitis, and (iv) imaging changes and symptoms and the development of the condition. In addition, there is no certainty that the benefit derived from the surgery is due to the removal of the acromion as research suggests that a bursectomy in isolation may confer equivalent benefit. It is also possible that the benefit of surgery is due to placebo or simply enforces a sustained period of relative rest which may allow the involved tissues to achieve relative homeostasis. It is possible that pathology originates in the tendon and as such surgery does not address the primary pathoaetiology. This view is strengthened by the findings of studies that have demonstrated no increased clinical benefit from surgery when compared with exercise. Additionally, exercise therapy is associated with a substantially reduced economic burden and less sick leave. Conclusion: As there is little evidence for an acromial impingement model, a more appropriate name may be ‘subacromial pain syndrome’. Moreover, surgery should only be considered after an appropriate period of appropriately structured rehabilitation.
Narrative Review
Subacromial impingement syndrome: a
musculoskeletal condition or a clinical
illusion?
Jeremy S Lewis
1,2,3,4
1
Therapy Department, Chelsea and Westminster Hospital,
2
Physiotherapy Department, St George’s Hospital,
3
Musculoskeletal Service, Central London Community Healthcare,
4
St George’s University of London, London,
UK
Background: Subacromial impingement syndrome is considered by many to be the most common of the
musculoskeletal conditions affecting the shoulder. It is based on a hypothesis that acromial irritation leads
to external abrasion of the bursa and rotator cuff.
Objectives: The aim of this paper is to review the evidence for the acromial irritation theory and in doing so
challenge the rationale for subacromial decompression.
Major findings: There is a body of evidence that suggests there is a lack of concordance regarding (i) the
area of tendon pathology and acromial irritation, (ii) the shape of the acromion and symptoms, (iii) the
proposal that irritation leads to the development of tendinitis and bursitis, and (iv) imaging changes and
symptoms and the development of the condition. In addition, there is no certainty that the benefit derived
from the surgery is due to the removal of the acromion as research suggests that a bursectomy in isolation
may confer equivalent benefit. It is also possible that the benefit of surgery is due to placebo or simply
enforces a sustained period of relative rest which may allow the involved tissues to achieve relative
homeostasis. It is possible that pathology originates in the tendon and as such surgery does not address
the primary pathoaetiology. This view is strengthened by the findings of studies that have demonstrated no
increased clinical benefit from surgery when compared with exercise. Additionally, exercise therapy is
associated with a substantially reduced economic burden and less sick leave.
Conclusion: As there is little evidence for an acromial impingement model, a more appropriate name may
be ‘subacromial pain syndrome’. Moreover, surgery should only be considered after an appropriate period
of appropriately structured rehabilitation.
Keywords: Shoulder, Subacromial impingement syndrome, Subacromial bursa, Acromioplasty, Subacromial decompression, Rotator cuff tendinopathy,
Shoulder posture
Background
The shoulder complex has a range of movement that
exceeds any other joint in the body and its main
function is to position the hand to affect functional
activities ranging from the performance of high
powered explosive activities, such as throwing base-
balls, to positioning the hand, often within the field of
vision, to perform highly complex prehensile tasks.
The shoulder is also used to place the hand so that
the upper limb may be used for weight bearing.
Musculoskeletal pathology involving the shoulder is
common, has the potential to adverse ly affect upper
limb function and is associated with substantial
morbidity that increases with age.
1–3
Of the wide
spectrum of musculoskeletal disorders affecting the
shoulder, subacromial impingement syndrome is
considered to be one of the most common.
4,5
This
condition is well recognized clinically, presenting as
antero-lateral shoulder pain experienced when the
arm is elevated.
4–7
Although numerous historic
references to subacromial pathology exist,
8–13
Neer
argued that abrasion by the under surface of the
anterior margin of the acromion onto the soft tissues
located anatomically in the space between the
humeral head and acromion leads to the symptoms
experienced in subacromial impingement syndrome.
4
He stated that this compression occurred principally
in forward elevation and described a clinical test, the
‘(Neer) impingement sign’ to reproduce the asso-
ciated symptoms.
5
The test involves restricting sca-
pular movement and forcing the arm into flexion
while the shoulder remains internally rotated.
5
According to Neer, this manoeuvre causes the greater
Physical Therapy Reviews ptr7245.3d 18/7/11 17:44:22
The Charlesworth Group, Wakefield +44(0)1924 369598 - Rev 7.51n/W (Jan 20 2003)
Correspondence to: Dr J S Lewis, Therapy Department, Chelsea and
Westminster Hospital NHS Foundation Trust, 369 Fulham Road, London
SW10 9NH, UK. Email: jeremy.lewis@chelwest.nhs.uk
ß
W. S. Maney & Son Ltd 2011
DOI 10 .1179/1743288X11 Y.0000000027
Physical Therapy Reviews 2011 VOL. 000 NO .000 1
tuberosity to impinge against the acromion. He
argued that 95% of rotator cuff tears are initiated
by impingement and that trauma may enlarge a tear
but is rarely the principal factor. Neer described three
stages of the impingement process. The first occurs in
people under 25 years of age and is associated with
tendinous oe dema and haemorrhage, and does not
require surgery. The second involves tendinitis and
occurs in people aged 25 to 40 and bursectomy and
coracoacromial ligament division should be consid-
ered after 18 months of conservative treatment. Neer
stated that in this group an acromioplasty is not
usually required. The third stage occurs in people
over 40 years of age and is associated with bone spurs
and tendon rupture and requires anterior acromio-
plasty. Neer stated that the reason rotator cuff tears
develop in some people and not others is principally
due to the shape of the acromion.
5
This hypothesis
was supported by Bigliani et al.
14
who described three
distinct morphological variations of acromial shape.
Bigliani et al.
14
argued that as a result of the shape
and the damage it would cause, those with a Type III
or hooked acromion were more likely to experience
subacromial impingement syndrome and suffer a
rotator cuff tear. Prior to Neer
4,5
presenting his
model, surgeons were performing complete acromio-
nectomies and lateral acromioplasties to alleviate the
symptoms. Basing his argument on intra operative
and cadaver observations, Neer
4,5
asserted that
removal of the inferior aspect of the anterior
acromion had greater efficacy. To augment the
procedure, he suggested that a partial resection of
the coracoacromial ligament together with surgery to
remove a hypertrophic acromioclavicular joint may
be required to arrest the impingement process.
Neer’s impingement model has been widely
embraced by surgeons, sports physicians and physical
therapists. So much in fact, that the percentage of
acromioplasties performed in New York State (USA)
alone has increased 254% in the 10 years from 1996 to
2006. The number of procedures has increased from 30
per 100 000 people (5571 operations) to 102 per
100 000 (19 743 operations).
15
Ketola et al.
16
reported
that the average cost of an acromioplasty and post-
surgical rehabilitation in Finland was J2961 (equiva-
lent to GB£2479, US$4017). In London, UK, an
average price for a series of quotations for private
subacromial decompression was GB£3500. In New
York State, a figure of US$4860 has been given. If this
is a representative amount, then staggeringly, the total
cost of performing acromioplasties in New York State
alone would be in the order of US$95 959 980. These
figures are not definitive and costs in some centres may
be less and in others higher. Nonetheless this is of
substantial economic burden and healthcare concern,
as Ketola et al.
16
have stated:
‘Arthroscopic acromioplasty provides no clinically
important effects over a structured and supervised
exercise programme alone in terms of subjective
outcome or cost-effectiveness when measured at
24 months. Structured exercise treatment should be
the basis for treatment of shoulder impingement
syndrome, with operative treatment offered judi-
ciously until its true merit is proven’.
This begs the question that if surgery aiming to
remove the cause of the impingement irritation (i.e.
the acromion) is no more clinically effective than a
substantially less expensive structured rehabilitation
programme,
16–18
then is the original hypothesis
correct, is the procedure valid, or is there an
alternative explanation for the symptoms?
Objectives
The aim of this paper is to review the evidence for the
acromial irritation theory and in doing so challenge
the rationale for the surgical removal of the inferior
aspect of the anterior acromion to remove the source
of symptoms.
Objective Findings
Area of pathology
If 95% of rotator cuff failure is caused by mechanical
irritation by the unde r surface of the acromion or
coracoacromial ligament,
5
then this should result in
abrasion to the superior (bursal side) surface of the
rotator cuff, especially the supraspinatus. Published
research disputes this. Payne et al.
19
reported that 39
(91%) partial thickne ss tears in 43 athletes were on
the inferior (articular or joint) side of the supraspi-
natus tendon with only 4 (9%) on the superior or
bursal side. In this series, 100% of those with non-
traumatic sho ulder pain had articular side tears.
Fukuda et al.
20
reported that in a study of 249
cadavera, 13% (n533) demonstrated partial thickness
tears. Of the partial thickness tears 82% were either
joint side or intra-tendinous (n527) and only 28%
(n56) were isolated to the upper bursal/acrom ial side.
Ozaki et al.
21
examined 200 shoulders from 1 00
cadavera and reported that a partial thickness tear
was observed in 69 specimens and that the major ity
involved the deeper articular side of the tendon. They
argued that the prevalence of tears increased with age
and occurred due to intrinsic degeneration and not
external (acromial) irritation. In a study of 306
rotator cuff specimens (from 153 cadavera) the
prevalence of partial thickness tears was 32%, with
histological and scanning electron microscopy sec-
tions demonstrating that the majority were either
intra-substance or occurred on the articular side of
the supraspinatus tendon, near the insertion.
22
This
study did not find a correlation between anatomical
bony variations and tendon failure and argued that
mechanical abrasion may not play an important part
Physical Therapy Reviews ptr7245.3d 18/7/11 17:44:23
The Charlesworth Group, Wakefield +44(0)1924 369598 - Rev 7.51n/W (Jan 20 2003)
Lewis Subacromial impingement syndrome
2 Physical Therapy Reviews 2011 VOL.000 NO.000
in the initial pathogenesis of degenerative rotator cuff
tears. Ellman
23
reported that partial thickness tears
were foun d in 15% (n520) of people undergoing
arthroscopic subacromial decompression (n5130).
He reported that when the findings of his observa-
tional work was combined with the findings of five
other studies
23
a total sample of 160 partial thickness
tears was produced, and of these the location was
reported in 126 cases. From these 126 cases, 76%
(n596) had articular side tears, 14% (n517) had
bursal side, and 10% (n513) had both. This repeated
and consistent finding that the predominance of
partial thickness tears occurs on the de eper articular
side of the tendon substantially challenges the
hypothesis that 95% of rotator cuff tears are caused
by acromial abrasion. Furthermore, Codman
10
al-
ready in 1934 observed that the rotator cuff de-
generates within the substance of the tendon or
frequently along the inferior margin of the tendon,
the side opposite the acromion, calling partial
thickness tears in this region, ‘rim rents’. He stated,
‘…I am confident that these rim rents accou nt for the
great majority of sore shoulders. It is my unproved
opinion that many of these lesions never heal,
although the symptoms caused by them usually
disappear after a few months’. The weight of evidence
supports Codman’s early observations that although
the acromion may be involved, the tendon may
structurally fail without direct mechanical irritation
from the overlying acromion. Supporting this con-
tention, Hashimoto et al.
24
observed diffuse degen-
erative changes involving tendon thinning, fibre
disorientation, myxoid and hyaline degeneration,
calcification, and chondroid metaplasia to be more
prominent in the middle and deeper rotator cuff
tendon layers, suggesting intrinsic tendon failure.
Variations observed in the morphology of the
supraspinatus tendon support these findings.
25
In a
histological and biomechanical investigation of 20
normal rotator cuff tendons, the deeper, non-
acromial, side fibres were reported to have a smaller
cross-sectional area than the superior acromial side
fibres.
25
In addition, when stretched to the point of
rupture, the deeper fibres were found to be more
vulnerable to tensile load than the bursal side fibres,
with the deeper fibres failing at approximately half
the tensile load of the failure point of the upper
acromial side fibres.
25
Supporting this finding, Bey
et al.
26
in a study of seven cadaveric shoulders
reported that when placed at 15, 30, 45 and 60u of
glenohumeral abduction, strain within the supraspi-
natus tendon increased with increasing joint eleva-
tion. At 60u elevation there was no significant
difference in strain between the superior, middle
and inferior portions of the tendon. However and
importantly, as the inferior fibres are comparatively
weaker,
25
Bey et al.
26
argued that the fibres in the
inferior region are relatively more susceptible to
failure in elevation. This is of clinical relevance as
many vocational activities and sporting pursuits
involve placing the shoulder in elevation for pro-
longed periods. As significantly more strain is placed
on the inferior fibres at 45 and 60u abduction than at
15 and 30u, and the deeper side fibres are relatively
weaker and fail earlier than the larger acromial side
fibres, it is arguable that the acromion has little or
nothing to do with the failure, which potentially may
result from the deeper side fibres passing their
physiological failure point.
As there is a lack of concordance between the area
of structural failure observed in the supraspinatus
tendon and the area predicted by an acromial
irritation model, others have suggested that the
observed joint side structural pathology is better
explained by external impingement between the
superior aspect of the glenoid fossa and the humeral
head. This alternative external irritation model has
been referred to as superior, postero-superior and
internal impingement.
27–30
However, robust evidence
required to support this model of impingement is
lacking, and as such it is possible that the deep side
tendon failure described in this model might not
result from external (extrinsic) impingement but may
result because of the heterogeneity of the fibre
distribution of the upper and lower aspects of the
supraspinatus tendon, together with the disparity of
tendon loading patterns during movement.
25,26,31
Recent reviews on the rotator cuff exploring these
and related issues have been published.
32,33
More than 70 years ago, Lindblom and Palmer
34
suggested that during shoulder abduction uneven
loads may be placed on the uppe r and lower aspects
of the tendon resulting in intratendinous shearing,
which may play a part in rotator cuff degeneration
and tears. This is relevant as the supraspinatus
tendon is made up of structurally independent
parallel fascicles
35,36
and movement will potentially
lead to different length tension relationships occur-
ring within and between the different fascicles. For
example, at the extreme of shoulder horizontal
abduction the anterior part of the tendon may be
relatively lengthened and the posterior shortened,
whereas at the extreme of horizontal adduction this
pattern may be reversed. As a greater range of
movement is required of the shoulder than any other
joint in the body it is conceivable that internal tendon
shearing may result that may predispose pathology
without the need for external compression on either
the superior or inferior aspects of the tendon. In
support of this, external irritation, in the form of an
Achilles tendon allograft wrapped around the left
acromion, in rats, did not lead to rotator cuff
Physical Therapy Reviews ptr7245.3d 18/7/11 17:44:23
The Charlesworth Group, Wakefield +44(0)1924 369598 - Rev 7.51n/W (Jan 20 2003)
Lewis Subacromial impingement syndrome
Physical Therapy Reviews 2011
VOL. 000 NO.000 3
pathology. However, intrinsic overload in the form of
downhill eccentric running for 4, 8 and 16 weeks did.
The rats subject to overuse (running) demonstrated
an increase in cross-sectional area and reduced
maximal strain at all time points. A combination
group (allograft and overloa d) lead to the greatest
change, suggesting that compression potentiated
overload even though compression alone did not
produce pathology.
37–39
These findings suggest that
external compression is insufficient to cause pathol-
ogy unless there is a concomitant history of tendon
overload, suggesting that the primary pathoaetiology
occurs within the tendon. It is accepted that due to
differences in morphology and biomechanics, caution
is necessary with direct translation from animal
studies. Evolution of the human upper limb may
place biomechanical constraints on the modern
shoulder which make it less capable of sustaining
positions of elevation.
40
If this is the case, then work,
recreational and sporting activities performed above
90u of elevation may selectively affect the weaker,
more vulnerable joint side fibres without the need for
acromial compression.
Acromial shape
Based on a study of 140 shoulders in 71 cadavers,
Bigliani et al.
14
argued that three distinct shapes of
the acromion existed. These morphological variations
included a Type I (flat), Type II (curved) and Type III
or hooked acromion. If the acromion is responsible
for 95% of rotator cuff pathology and is the causat ive
mechanism of pathology in impingement syndrome,
then a definitive relationship between acromial shape,
pathology and symptoms sho uld exist with a Type II
or III more likely to predispose pathology. However,
research evidence has failed to demonstrate this.
In a study of 59 people without shoulder pain the
association between acromial morphology, age and
rotator cuff tears was investigated.
41
For people over
the age of 50 years, a 40% prevalence of asympto-
matic full thickness rotator cuff tears was identified in
this investigation. Based on the substantial number of
people with curved and hooked acromia who were
entirely asymptomatic, Worland et al.
41
concluded
that, ‘Surgeons should interpret radiologically hook-
ed or curved acromions as well as rotator cuff tears
diagnosed with ultrasound or other modalities with
caution’. In a study of 55 people who underwent
arthroscopic subacromial decompression (anterolat-
eral edge of the acromion resected together with
release and resection of the coracoacromial ligament
from the acro mion), the association between pre-
operative pain, clinical signs (Hawkins test, Neer
sign, Copeland impingement test) and satisfaction
with the severity of rotator cuff and acromial lesions
was investigated. At the 6 month follow-up no
significant correlation between pain and satisfa c-
tion and the severity of structural pathology was
identified.
42
Confirming this, after a study of 523
people unde rgoing arthroscopic or open shoulder
surgery, Gill et al.
43
reported no significant associa-
tion between acromial shape and rotator cuff pa-
thology in people over 50 years of age (n5192). A
highly significant correlation between age and rotator
cuff pathology existed and the researchers argued that
a Type III hooked acromial represents a degenerative
process rather than a morphological varia>tion as
described by Bigliani.
14,44
Although a relationship
between rotator cuff tears and acromial degeneration
appears to exist, this should be seen as an association,
rather than the acromion being implicated in (i.e. the
cause of) rotator cuff pathology.
An alternative explanation for the observed acro-
mial spurs is possible. Edelson and Taitz
45
observed
degenerative spur formation on the acromial insertion
of the coracoacromial ligament but not on the
coracoid side in 18% of 200 scapulae. When compared
with shoulder adduction, increasing ranges of shoul-
der elevation increase subacromial pressure.
46,47
The
coracoacromial ligament is more trapezoid in shape
with a smaller area of insertion on the acromial side
than the coracoid side. It is therefore possible that
superiorly directed pressure from below the ligament
will lead to relatively more tension on the acromial
insertion of the ligament than on the coracoid side due
to the smaller surface area of insertion on the former.
This potential increased stress on the bone may lead to
osteophyte formation. Supporting this hypothesis,
Chambler et al.
47
demonstrated in vivo (n55) that
tension in the coracoacromial ligament increased as
the arm was abducted. In an additional study
48
analysis of acromial bone spurs (n515) suggested that
the development of the spurs was a secondary
phenomenon. These studies suggest that tension in
the coracoacromial ligament is the probable mechan-
ism of acromial bone spur formation and that
acromial Type II (curved) and Type III (hooked) as
described by Bigliani
14,44
may not be inherited, but
may result from increased strain in the ligament
disproportionally affecting the acromial side.
Chronic strain in the coracoacromial ligament may
result from changes in the rotator cuff tendons that
may involve increased tendon volume, as well as from
failure of the rotator cuff to stop superior translation
of the humeral head during arm elevation.
49–53
Evidence for chronic strain exists, with free nerve
endings and neovascularity observed in coracoacro-
mial ligament samples from people undergoing
subacromial decompression.
54
This suggests that the
ligament may be a potential source of symptoms. The
coracoacromial ligament limits superior translation
of the humeral head
55–57
and as acromioplasty has
Physical Therapy Reviews ptr7245.3d 18/7/11 17:44:24
The Charlesworth Group, Wakefield +44(0)1924 369598 - Rev 7.51n/W (Jan 20 2003)
Lewis Subacromial impingement syndrome
4 Physical Therapy Reviews 2011 VOL.000 NO.000
been associated with increased anterosuperior trans-
lation of the humeral head,
52,57–59
the procedure itself
may be an iatrogenic cause of ligament strain.
Ligaments are structures that stabilize joint move-
ment and if disrupted they are replaced in an attempt
to recreate stability. Examples of this include patellar
tendon and hamstrings tendon grafts for anterior
cruciate knee ligament failure.
60
It is therefore
surprising that the coracoacromial ligament, which
provides a stabilization role by preventing superior
translation of the humeral head,
61
has been exten-
sively sacrificed to retard or stop the subacromial
impingement, due to the belief that it is of relative
structural unimportance, when there is no conclusive
evidence to support the existence of primary external
impingement from this structure. It would be hard to
imagine that a surgeon would suggest, or a patient
would agree to, having the anterior cruciate ligament
removed to treat knee pain.
Posture and muscle imbalance
Physical therapists have also embraced the acromial
irritation model
62–65
and have argued that an
increased kyphosis, a change in scapular position
due to poor posture, uncontrolled scapular move-
ment (dyskinesis), or an imbalance in muscle activity
leads to subacromial impingement syndrome.
63,66–68
Even though concepts relating to pos ture and muscle
imbalance have existed for more than half a century it
is surprising how little evidence there is to support (i)
the existence of an ideal posture of the head, neck,
thorax, (ii) the existence of an ideal scapula r position
(i.e. the basis for scapula r setting exercises), (iii) that
uncontrolled scapular movement and dyskinesis is
always a primary problem, (iv) that postural devia-
tions and muscle length tension changes alter
scapular position in a consistent manner and sig-
nificantly lead to a detrimental effect of movement
and provoke impingement symptoms, (v) that reha-
bilitation can correct posture that is considered
abnormal, and (vi) the idea that this correction
leads to an improvement in function and a reduc-
tion in pain. There is evidence to challeng e these
concepts
69–76
which suggests that the certainty with
which this aspect of clinical practice is taught to
undergraduate and postgraduate students and
imparted to patients and clients requires robust
research enquiry. In addition, it is arguably inap-
propriate to suggest that an increased thoracic
kyphosis leads to restricted shoulder movement and
impingement based on studies that have unnaturally
restricted thoracic spine movem ent.
66,68
An assump-
tion implicit within the postural-muscle imbalance
model of assessment is that a forward head posture
and increased thoracic kyphosis observed during
static posture has a direct correlation on dynamic
movement, and that all scapulae have the same
geometric proportions and move in the same way on
the same shaped rib cage and thorax. This is simply
not correct
45,70,77,78
and as such, a one size fits all
approach is unlikely to be appropriate. Variations in
shoulder function may be dictated by variations in
structure, and the differences observed between
people with impingement syndrome may reflect a
range of normal values and not deviations from one
idealized normal posture. If this is correct it would
not be possible to identify pos tural deviations that
lead to subacromial impingement. Based on the
uncertainty of the current models of postural and
clinical assessment altern ative models of assessment
have been proposed;
69
however, these also require
clinical validation.
Tendinitis
Implicit within the three-stage impingement model
presented by Neer
4,5
is the association between the
mechanical abrasion caused by the acromion and the
ensuing microtrauma within the tendon leading to
tendon inflammation (tendinitis). The issue of tendon
inflammation is controversial. Although histological
studies have demonstrated substantial differences
between normal tendon and pathological tendon,
the evidence for the presence of cells classically
associated with inflammation is not robust. No
infiltration of neutrophils, lymphocytes or plasma
cells were identified in specimens taken from 12
subjects with rotator cuff disease during surger y.
79
Similarly, no inflammatory cells were identi fied in
bursal specimens (n58) also taken during surgery for
rotator cuff tendinopathy.
80
In another small study,
people with constant shoulder pain were more likely
to have lymphocyte infiltration in bursal tissue in
comparison to people with pain only on movement
who did not exhibit evidence of bursal inflammatory
cells.
81
There is distinct need for robust evidence from
appropriately designed research to better understand
if inflammation is part of the continuum of pathoae-
tiology of tendon and bursal pathology.
33
Without
this research an argument that acromial irritation and
the ensuring microtrauma leads to bursal and tendon
inflammation remains unsubstantiated.
The subacromial bursa
The subacromial bu rsa (SAB) separates the cora-
coacromial arch and deltoid above, and the rotator
cuff tendons below. Together with the other bursae
in the re gion, whose reported numbers ranging from
7/8 to 12, the SAB acts to r educe frictio n during
movement.
13,82
The SAB is innervated anteriorly by
the lateral pectoral nerve and posteriorly by the
suprascapu lar nerve.
83
The identification of mechan-
oreceptors and free nerve endings (Ad and C) in
bursal tissue suggests the SAB has a role in
Physical Therapy Reviews ptr7245.3d 18/7/11 17:44:24
The Charlesworth Group, Wakefield +44(0)1924 369598 - Rev 7.51n/W (Jan 20 2003)
Lewis Subacromial impingement syndrome
Physical Therapy Reviews 2011
VOL. 000 NO.000 5
proprioception zand nociceptio n.
84
The presence of
nociceptors is highly relevant as high concentrations
of pro-inflammatory cytokines, pain mediating sub-
stances and matrix modify ing proteins have been
identified in bursal tissue of people whose shoul-
der pai n is exacerbated by shoulder elevation.
85–91
Higher shoulder pain scores were reported by those
found to have higher concentrations of the cytoki ne
interleukin-1beta an d the neuropeptide, substance P,
in their bursal tissue.
86
One clinical trial randomized people diagnosed
with subacromial impingement syndrome (n557,
mean age 47 years), to Group I: arthroscopic ac-
romioplasty and bursectomy or Group 2: arthro-
scopic subacromial bursectomy alone. Good results
were reported in both groups with no significant
differences identi fied between the two groups at a
mean follow-up of 2.5 years.
92
These findings clearly
suggest that the bursa is a significant pain generator
and that the addition of an acromioplasty may be
superfluous. Henkus et al.
92
argued that subacromial
impingement syndrome is largely an intrinsi c degen-
erative condition rather than an extrinsic mechanical
disorder. The importance of the SAB as a source of
shoulder pain is reinforced by studies that have
shown that injections reaching the SAB reduced pain
while injections targeting other structures increased
or did not change pain.
93
This may be a reason why
ultrasound guided injections appear to produce better
outcomes than non-guided injections.
94,95
It is also unclear whether treatment with corticos-
teroid and lidocaine is any more advantageous than
lidocaine in isolation.
96–99
Using analgesic injections
as a control, systemic (gluteal) corticosteroid injec-
tions have been report ed to be as effective as locally
guided corticosteroid injections
99
in the treatment of
impingement syndrome. However, the certainty of
this conclusion is questioned by studies that have
shown no added long term effect of analgesic over
steroid,
96,97
and no one has yet shown the added
benefit of the pharmacological substance injected
over the mechanical stimulation of the dry needle,
which in itself is frequently painful. The science
supporting the use of injection therapy for impinge-
ment syndrome (timing, volume, medications used,
direction of injection, post-injection advice, histolo-
gical effect on tissues) is not robust and requir es
ongoing investigation. In the UK, many physical
therapists perform injections and an increasing
number are performing ultrasound guided injections.
Alongside this change to scope of practice is a
requirement for further research, which is essential to
understand the histological and biochemical nature
of bursal pathology and pain and the relationship
between bursal pathology, tendon pathology and
shoulder pain.
Alternative explanations for the potential benefit
of surgery
Success rates of 80–90% following subacromial decom-
pression for impingement have been reported.
100–103
Neer
5
and those embracing his model argue that
removing the acromion removes the source of irrita-
tion. Henkus et al.
92
has clearly demonstrated this may
not be the case, as isolated removal of the bursa has
comparable effects to removing the acromion and
bursa. However, in addition to the suggestion that
bursectomy is more relevant than acromioplasty,
92
other, additional explanations for the beneficial results
reported following acromioplasty are entirely feasible.
In Australia, non-manual workers take on average
6 weeks to return to work following an acromioplasty
and 85% of manual workers take 3 months to return to
employment, with driving commencing at 29 days
post-surgery.
104
Comparable findings from the UK
suggest that non-manual workers return to work after
9 days, manual workers after 3 weeks and driving
recommences after 13 days.
105
These data clearly
demonstrate that there is a prolonged period of
substantial relative rest following the procedure and
to date no study has compared surgery and the ensuing
relative rest with comparable relative rest alone. This
highly relevant issue of relative rest was suggested by
Lewis
33
as an essential component of treatment for
rotator cuff tendinopathy in a reactive stage. This will
be referred to again later in this paper. In addition, it is
possible that subacromial decompression is a placebo.
Moseley et al.
106
reported that 180 people with painful
knee osteoarthrosis randomized to either (i) arthro-
scopic lavage, or (ii) arthroscopic debridement or (iii)
placebo surgery (skin incisions) reported the same
improvement at 2 year follow-up. This strongly
suggests that the benefit reported for people under-
going arthroscopic surgery for painful degenerative
knees may be entirely attributable to the placebo effect.
This is not the first time that the benefit of surgery has
been attributed to placebo.
107,108
Additionally, to
reduce the economic burden on healthcare systems, it
would be very appropriate to recommend an appro-
priately structured period of relative rest and a
supervised and graduated exercise programme before
surgery is considered as non-surgical care is at least of
equivalent clinical benefit.
16–18
Clinical diagnosis
A diagnosis of subacrom ial impingement syndrome is
initially made on the basis of clinical tests. Neer
5
introduced the Neer impingement sign and others
have proposed other tests to confirm or exclude
impingement under the acromion.
109,110
The clinical
tests are often supported by imaging investigations.
However, the ability for clinical tests and imaging
investigations to enable a clinician to confirm a
diagnosis of subacromial impingement syndrome is
Physical Therapy Reviews ptr7245.3d 18/7/11 17:44:25
The Charlesworth Group, Wakefield +44(0)1924 369598 - Rev 7.51n/W (Jan 20 2003)
Lewis Subacromial impingement syndrome
6 Physical Therapy Reviews 2011 VOL.000 NO.000
contentious,
69,111–113
as imaging investigation s ha ve
consistently demonstrated structural pathology in a
high percentage of people without sympto ms.
As discussed earlier there is a poor correla-
tion between acromial radiological changes and
symptoms.
41–43
In a study of 96 people without
shoulder symptoms 28% or those aged between 40
and 60 years and 54% of those aged above 60 years
had MRI evidence of a partial or full thickness
rotator cuff tear.
114
Milgrom et al.
115
reported in a
study of 90 people (age range 30 to 99 without
shoulder symptoms) that the incidence of full
thickness rotator cuff tears identified by ultrasound
increased with advancing age and that after the 5th
decade approximately 50% of people had asympto-
matic full thickness tears that did not affect function.
In a study that compared 42 people with impinge-
ment syndrome with 31 age matched symptom free
controls, Frost et al.
116
reported that 55% of the
symptomatic group and 52% of the asymptomatic
group had eviden ce of rotator cuff pathology on
imaging. They also reported that pathology related to
age and did not correlate with symptoms.
Professional baseball pitchers have been reported to
pitch up to 165 km/hour and demonstrate internal
rotation velocities during pitching of 6100 to 6940u/
second.
117,118
These examples of extremely high levels
of function may be achieved even in the presence of
structural pathology. Miniaci et al.
119
reported that
14 professional baseball pitchers without shoulder
symptoms demonstrated rotator cuff changes in their
throwing (79%) and non-throwing (86%) shoulders
and labral changes (79%) in both shoulders.
Professional baseball pitchers and tennis players
without symptoms demonstrated partial and full
thickness tears (40%), glenohumeral joint effusions
(90%) and excess subacromial fluid (48%) in their
dominant shoulder and remained asymptomatic at a
5 year follow-up.
120
In addition, the sourcil (eye-
brow) sign observed radiologically as sclerosis on the
under surface of the acromion and consider ed to be
an indictor of rotator cuff pathology due to increased
pressure (impingement) was found not to correlate
with clinical signs of impingement, rotator cuff tears,
or age, and did not aid diagnosis in 175 people with
shoulder pain.
121
Lewis et al.
122
demonstrated that
neovascularity may be present in both the sympto-
matic and asymptomatic shoulders of people diag-
nosed with unilateral rotator cuff pathology.
These imaging studies demonstrate that high
percentages of people without symptoms will have
evidence of structural failure and at present there is
no clinical certainty that imaging abnormalities are
the cause of the presenting impingement symptoms.
Observation of structural pathology identified in
radiographs, ultrasound, MRI and arthroscopy are
frequently employed as the gold standard comparator
in studies designed to test the diagnostic accuracy,
sensitivity, specificity, positive and negative predictive
values, and positive and negative likelihood ratios.
However, if the gold standard is not robust (i.e.
people wi thout shoulder symptoms have structural
failure
114–116,119,122
) then a concomitant high percen-
tage of false positives would not provide the
confidence required by a clinician to make a diagnosis
with any certainty.
This is of major concern as surgery may be
recommended to people diagnosed with impingement
syndrome based on clinical tests and supported by
imaging findings that are currently incapable of
conclusively confirming such a diagnosis.
69,111,112
The consequence of this is that for a substantial
percentage of people the surgery may be unnecessary,
inappropriate and unwarranted. This is clearly high-
lighted by the number of studies that do not show
added benefit of surgery over non-surgical care.
16–18
In addition, surgery carries risks, such as infections,
and is substantially more expensive.
16,123
Therefore,
an appropriate and defensible argument is that until a
robust method of confirming a diagnosis is obtain-
able, and until clear evidence concerning the pathol-
ogy is available, surgery should only be offered after
an appropriate period of appropriate non-surgical
care.
Tendinopathy
Shalabi et al.
50
performed an MRI investigation of
the Achilles tendon (n544 from 22 people, 30
symptomatic and 14 asymptomatic tendons) imme-
diately before and within 30 minutes of an intense
bout of concentric (bilateral heel raises) and/or
eccentric (6 sets of 15 repetitions) gastrosoleus
exercises. They reported a 12% increase in tendon
volume in the eccentrically loaded symptomatic
Achilles tendons and a 17% increase in the
concentrically loaded tendons (mixed symptomatic
and asymp tomatic) Achilles tendons. There was a
20% increase in t endon volume in the concentrically
loaded asymptomatic Achilles tendons. Rats sub-
ject to a tendon overload programme have also
demonstrated an increase in rotator cuff cross-
sectional area.
37
Increased rotator cuff tendon
volume as a result of unaccustomed activity or
activity at an intensity that surpasses the physiolo-
gical limit of the tendon (which will be highly
variable between and within individuals) may lead
to increased upward pressure on the acromion and
coracoacromial ligament. This increased strain in
the l igament is a possible aetiological mechanism
for acromial spur formation and as such the
acromial osteophyte may not be the primary
problem but secondary to the increased tendon
Physical Therapy Reviews ptr7245.3d 18/7/11 17:44:25
The Charlesworth Group, Wakefield +44(0)1924 369598 - Rev 7.51n/W (Jan 20 2003)
Lewis Subacromial impingement syndrome
Physical Therapy Reviews 2011
VOL. 000 NO.000 7
volume. If the increased volum e and resulting
ligamentous strain occurs at a subclinical level
from bursts of activity or spor t a s pur m ay de vel op
over time but may remain asymptomatic over a
lifetime and explain the poor correlation between
acromial shape and symptoms.
41–43
Overuse tendinopathies involving the la teral epi-
condyle, patellar, adductor and Achilles tendons
may occur without impingement from external
structures such as adjacent bony surfac es, and this
may also be the case for the rotator c uff. It is
possible that the external irritation accentuates the
tendon failure
37–39,124
but it is unlikely that it is the
prim ary cause. The failure is lik ely to be due to a
combination of factors including: relative overload,
gene tics, nutritional and life style variabl es,
32
and
the rotator cuff tendon failure may be seen as a
continuum of pathology.
33
The initial symptomatic
stage of the continuum of pathology has been
term ed a reactive tendon,
33,125
which may be cha-
racterized by increased tenocyte numbers.
126
In-
creased expression of the large negatively charged
proteoglycan aggrecan is observed in painful overuse
tendinopathy.
127,128
Due to its negative charge aggre-
can attracts and retains water, which explains the
swelling observed in acute Achilles tendinopathy.
50
The non-steroidal anti-inflammatory drug, ibuprofen,
appears to inhibit the synthesis of aggrecan
129
and
may be an appropriate treatment at this stage.
Additionally, glucocorticoids have been shown to
inhibit tenocyte proliferation,
130
which may explain
the benefit ascribed to corticosteroid injections for
the shoulder in some people.
98
However as stated, the
long term efficacy and potential detrimental effects of
corticosteroid injections for the shoulder require on
going investigation.
The other pathological stages associated with rota-
tor cuff tendinopathy (disrepair and degeneration)
33
may have an associated element of reactivity. When
reactivity is present tendon thickening and swe lling
is possib le. If this pathoaetiology is accurate and if
the pathology is correctly explained by intrinsic
tendon failure as a consequence of relative ove rload
then it simply may be the swollen tendon pushing up
and not the acr omion pushing down that is the cause
of the problem. If this hypothesis is correct, then an
acromiopl asty will not treat the primary problem
(i.e. intrinsic tendon failure) or provide appropriate
init ial management for the condition. If relative rest
and appropr iate reloading strategies are principal
factors in tendon rehabilitation it is possible that a
major benefit of an acromioplasty is enforced
relative rest .
104,105
If this is correct, the associate
expe nse, potential risks and lack of appropr iately
targeted treatment question its utility as a first line
treatment option.
Surgery versus non-surgical management
As mentioned, reports of 80–90% success following
subacromial decompression for impingement have
been published.
100–102
When acromioplast y was com-
pared with conservative care (physiotherapy exercises
and pain relief) surgery appeared to be no more
beneficial clini cally at 6, 12 or 48 months.
16–18
As
elucidated earlier there is no certainty that the benefit
relates directly to the stated aim of the surgery (i.e.
removal of the acromion) and benefit may be derived
from the bursectomy, the period of post-surgical
relative rest, and potentially placebo. Relative rest is
of relevance as Cook and Purdam
125
in a generic
model of overuse tendinopathy, have suggested that
tendon load management and reduction in frequency
and/or intensity of tendon load is important during
the reactive phase. Relative rest may also be
important in the reactive stage of rotator cuff
tendinopathy.
33
Relative rest may allow the tendon
to attain relative homeostasis, by reducing the up
regulation of tenocytes that may be characteristic of a
reactive tendon and thereby reduce the associated
swelling before a graduated and appropriately con-
structed rehabilitation programme is instigated. It
may be possibly to enhance the exercise prescription
that has been utilized in clinical trials by more
effectively targeting the stage of the rotator cuff
tendinopathy.
33,131
In addition, consideration of the
varying effects exercise may have on subacromial
pressure
46
is relevant. To further reduce upward
humeral head translation and tendon compression,
avoidance of internal rotation in the early stages of
rehabilitation may be appropriate. Although uncer-
tainty exists,
132
it may be possible to enhance the
effect of exercise by including manual therapy in the
treatment package.
133,134
These issues relating to
rehabilitation need to be appropriately scrutinized
through robust research investigations.
Conclusion
Subacromial impingement syndrome is considered by
many to be the most common of the musculoskeletal
conditions affecting the shoulder. It is based on a
hypothesis that acromial irritation leads to external
abrasion of the bursa and rotator cuff. Subacromial
decompressive surgery aims to remove the source of
this irritation. There is however a body of evidence
that suggests there is a lack of concordance regarding
(i) the area of tendon pathology and acromial
irritation, (ii) the shape of the acromion and
symptoms, (iii) the proposal that the irritation leads
to the development of tendinitis and bursitis, and (iv)
imaging changes and symptoms and the development
of the condition. In addition, there is no certainty
that any benefit derive d from the surgery is due to the
removal of the acromion as research suggests that a
Physical Therapy Reviews ptr7245.3d 18/7/11 17:44:25
The Charlesworth Group, Wakefield +44(0)1924 369598 - Rev 7.51n/W (Jan 20 2003)
Lewis Subacromial impingement syndrome
8 Physical Therapy Reviews 2011 VOL.000 NO.000
bursectomy in isolation may confer equivalent
benefit. It is also possible that the benefit of surgery
is that it simply enforces a sustained period of relative
rest which may allow the involved tissues to achieve
relative homeostasis. It is possible that pathology
originates in the tendon and as such surgery does not
address the primary problem. This view is strength-
ened by the findings of studies that have demon-
strated no increased clinical benefit from surgery
when compared with exercise, with exercise therapy
being associated with a substantially reduced eco-
nomic burden and less sick leave. Evidence based
healthcare involves the integration of clinical exper-
tise, patient values and best research evidence. To
provide the research evidence required, surgeons
performing acromioplasties need to demonstrate that
it is the acromioplasty that is beneficial and not the
enforced reduction in acti vity or the possibility of
placebo. As there is little evidence for an acromial
impingement model a more appropriate name may be
‘subacromial pain syndrome’. Moreover, surgery
should only be considered after an appropriate period
of appropriately structured conservative treatment.
Acknowledgements
Aspects of the information contained in this paper
were presented as a key note lecture entitled
‘Subacromial impingement syndrome. A musculos-
keletal condition or a clinical illusion?’ at the 11th
International Conference of Shoulder and Elbow
Surgeons, Edinburgh, Scotland, UK, 5–8 September
2010.
References
1 Brox JI. Regional musculoskeletal conditions: shoulder pain.
Best Pract Res Clin Rheumatol 2003;17:33–56.
2 van der Heijden GJ. Shoulder disorders: a state-of-the-art
review. Baillieres Best Pract Res Clin Rheumatol 1999;13:287–
309.
3 Taylor W. Musculoskeletal pain in the adult New Zealand
population: prevalence and impact. NZ Med J 2005;118:
U1629.
4 Neer CS, 2nd. Anterior acromioplasty for the chronic
impingement syndrome in the shoulder: a preliminary report.
J Bone Joint Surg Am 1972;54:41–50.
5 Neer CS, 2nd. Impingement lesions. Clin Orthop Relat Res
1983;173:70–7.
6 Bigliani LU, Levine WN. Subacromial impingement syn-
drome. J Bone Joint Surg Am 1997;79:1854–68.
7 Michener LA, Walsworth MK, Doukas WC, Murphy KP.
Reliability and diagnostic accuracy of 5 physical examination
tests and combination of tests for subacromial impingement.
Arch Phys Med Rehabil 2009;90:1898–903.
8 Adam R, Todd, RB. Shoulder joint. In: Todd RB, editor.
Cyclopaedia of anatomy and physiology. Vol. 4. London:
Longman; 1852. p. 571–621.
9 Meyer A. The minuter anatomy of attrition lesions. J Bone
Joint Surg Am 1931;13:341–60.
10 Codman E. The shoulder: rupture of the supraspinatus tendon
and other lesions in or about the subacromial bursa. Boston:
Thomas Todd Company; 1934. p.18–31, , 65–107.
11 Bosworth D. Analysis of 28 consecutive cases of incapacitating
shoulder lesions radically explored and repaired. J Bone Joint
Surg Am 1940;22:369–92.
12 McLaughlin H, Asherman EG. Lesions of the musculotendi-
nous cuff of the shoulder. IV. Some observations based upon
the results of surgical repair. J Bone Joint Surg Am
1951;33:76–86.
13 Diamond B. The obstructing acromion: underlying diseases,
clinical development, and surgery. Springfield: Charles C.
Thomas; 1964. p. 53–120.
14 Bigliani LU, Morrison DS, April EW. The morphology of the
acromion and its relationship to rotator cuff tears. Ortho
Trans 1986;10:228.
15 Vitale MA, Arons RR, Hurwitz S, Ahmad CS, Levine WN.
The rising incidence of acromioplasty. J Bone Joint Surg Am
2010;92:1842–50.
16 Ketola S, Lehtinen J, Arnala I, Nissinen M, Westenius H,
Sintonen H, et al. Does arthroscopic acromioplasty provide
any additional value in the treatment of shoulder impingement
syndrome? a two-year randomised controlled trial. J Bone
Joint Surg Br 2009;91:1326–34.
17 Haahr JP, Ostergaard S, Dalsgaard J, Norup K, Frost P,
Lausen S, et al. Exercises versus arthroscopic decompression
in patients with subacromial impingement: a randomised,
controlled study in 90 cases with a one year follow up. Ann
Rheum Dis 2005;64:760–4.
18 Haahr JP, Andersen JH. Exercises may be as efficient as
subacromial decompression in patients with subacromial stage
II impingement: 4–8-years follow-up in a prospectiv e,
randomized study. Scand J Rheumatol 2006;35:224–8.
19 Payne LZ, Altchek DW, Craig EV, Warren RF. Arthroscopic
treatment of partial rotator cuff tears in young athletes. A
preliminary report. Am J Sports Med 1997;25:299–305.
20 Fukuda H, Mikasa M, Yamanaka K. Incomplete thickness
rotator cuff tears diagnosed by subacromial bursography. Clin
Orthop Relat Res 1987;223:51–8.
21 Ozaki J, Fujimoto S, Nakagawa Y, Masuhara K, Tamai S.
Tears of the rotator cuff of the shoulder associated with
pathological changes in the acromion. A study in cadavera.
J Bone Joint Surg Am 1988;70:1224–30.
22 Loehr JF, Uhthoff HK. The pathogenesis of degenerative
rotator cuff tears. Orthop Trans 1987;11:237.
23 Ellman H. Diagnosis and treatment of incomplete rotator cuff
tears. Clin Orthop Relat Res 1990;254:64–74.
24 Hashimoto T, Nobuhara K, Hamada T. Pathologic evidence
of degeneration as a primary cause of rotator cuff tear. Clin
Orthop Relat Res 2003;415:111–20.
25 Nakajima T, Rokuuma N, Hamada K, Tomatsu T, Fukuda H.
Histological and biomechanical characteristics of the supraspi-
natus tendon. J Shoulder Elbow Surg 1994;3:79–87.
26 Bey MJ, Song HK, Wehrli FW, Soslowsky LJ. Intratendinous
strain fields of the intact supraspinatus tendon: the effect of
glenohumeral joint position and tendon region. J Orthop Res
2002;20:869–74.
27 Walch G, Boileau P, Noel E, Donell ST. Impingement of the
deep surface of the supraspinatus tendon on the poster-
osuperior glenoid rim: an arthroscopic study. J Shoulder
Elbow Surg 1992;1:238–45.
28 Jobe CM, Sidles JA. Evid ence for a superior gleno id
impingement upon the rotator cuff [abstract]. J Shoulder
Elbow Surg 1993;2(Suppl):S19.
29 Riand N, L evigne C, Renaud E, Walch G. Results of
derotational humeral osteotomy in posterior glenoid impinge-
ment. Am J Sports Med 1998;26:453–9.
30 Edelson G, Teitz C. Internal impingement in the shoulder.
J Shoulder Elbow Surg 2000;9:308–15.
31 Nakajima T, Hughes RE, An KN. Effects of glenohumeral
rotations and translations on supraspinatus tendon morphol-
ogy. Clin Biomech (Bristol, Avon) 2004;19:579–85.
32 Lewis JS. Rotator cuff tendinopathy. Br J Sports Med
2009;43:236–41.
33 Lewis JS. Rotator cuff tendinopathy: a model for the
continuum of pathology and related management. Br J
Sports Med 2010;44:918–23.
34 Lindblom K, Palmer I. Ruptures of the tendon aponeurosis of
the shoulder joint. Acta Chir Scand 1939;82:133–42.
35 Clark JM, Harryman DT, 2nd. Tendons, ligaments, and
capsule of the rotator cuff. Gross and microscopic anatomy.
J Bone Joint Surg Am 1992;74:713–25.
36 Fallon J, Blevins FT, Vogel K, Trotter J. Functional
morphology of the supraspinatus tendon. J Orthop Res 2002;
20:920–6.
37 Soslowsky LJ, Thomopoulos S, Tun S, Flanagan CL, Keefer
CC, Mastaw J, et al. Neer Award 1999. Overuse activity
injures the supraspinatus tendon in an animal model: a
Physical Therapy Reviews ptr7245.3d 18/7/11 17:44:26
The Charlesworth Group, Wakefield +44(0)1924 369598 - Rev 7.51n/W (Jan 20 2003)
Lewis Subacromial impingement syndrome
Physical Therapy Reviews 2011
VOL. 000 NO.000 9
histologic and biomechanical study. J Shoulder Elbow Surg
2000;9:79–84.
38 Perry SM, McIlhenny SE, Hoffman MC, Soslowsky LJ.
Inflammatory and angiogenic mRNA levels are altered in a
supraspinatus tendon overuse animal model. J Shoulder
Elbow Surg 2005;14(Suppl):S79–83.
39 Carpenter JE, Flanagan CL, Thomopoulos S, Yian EH,
Soslowsky LJ. The effects of overuse combined with intrinsic
or extrinsic alterations in an animal model of rotator cuff
tendinosis. Am J Sports Med 1998;26:801–7.
40 Lewis J, Green A, Yizhat Z, Pennington D. Subacromial
impingement syndrome: Has evolution failed us? Physiother
2001;87:191–8.
41 Worland RL, Lee D, Orozco CG, SozaRex F, Keenan J.
Correlation of age, acromial morphology, and rotator cuff
tear pathology diagnosed by ultrasound in asymptomatic
patients. J South Orthop Assoc 2003;12:23–6.
42 Snow M, Cheong D, Funk L. Subacromial impingement: is
there correlation between symptoms, arthroscopic findings
and outcomes? Shoulder Elbow 2009;1:89–92.
43 Gill TJ, McIrvin E, Kocher MS, Homa K, Mair SD, Hawkins
RJ. The relative importance of acromial morphology and age
with respect to rotator cuff pathology. J Shoulder Elbow Surg
2002;11:327–30.
44 Bigliani LU, Ticker JB, Flatow EL, Soslowsky LJ, Mow VC.
The relationship of acromial architecture to rotator cuff
disease. Clin Sports Med 1991;10:823–38.
45 Edelson JG, Taitz C. Anatomy of the coraco-acromial arch.
Relation to degeneration of the acromion. J Bone Joint Surg
Br 1992;74:589–94.
46 Werner CM, Blumenthal S, Curt A, Gerber C. Subacromial
pressure s in vivo and effects of selective experimental
suprascapular nerve block. J Shoulder Elbow Surg 2006;
15:319–23.
47 Chambler AF, Bull AM, Reilly P, Amis AA, Emery RJ.
Coracoacromial ligament tension in vivo. J Shoulder Elbow
Surg 2003;12:365–7.
48 Chambler AF, Pitsillides AA, Emery RJ. Acromial spur
formation in patients with rotator cuff tears. J Shoulder Elbow
Surg 2003;12:314–21.
49 Sarkar K, Taine W, Uhthoff HK. The ultrastructure of the
coracoacromial ligament in patients with chronic impingement
syndrome. Clin Orthop Relat Res 1990 254:49–54.
50 Shalabi A, Kristoffersen-Wiberg M, Aspelin P, Movin T.
Immediate Achilles tendon response after strength training
evaluated by MRI. Med Sci Sports Exerc 2004;36:1841–6.
51 Sharkey NA, Marder RA. The rotator cuff opposes superior
translation of the humeral head. Am J Sports Med
1995;23:270–5.
52 Lazarus MD, Yun g S W, Sidles JA, Harryman DT.
Anterosuperior humeral head displacement: limitation by the
coracoacromial arch. J Shoulder Elbow Surg 1996;5:S7.
53 Thompson WO, Debski RE, Boardman ND, 3rd, Taskiran E,
Warner JJ, Fu FH, et al. A biomechanical analysis of rotator
cuff deficiency in a cadaveric model. Am J Sports Med
1996;24:286–92.
54 Tamai M, Okajima S, Fushiki S, Hirasawa Y. Quantitative
analysis of neural distribution in human coracoacromial
ligaments. Clin Orthop Relat Res 2000;373:125–34.
55 Flatow EL, Wang VM, Kelkar R. The coracoacromial
ligament passively restrains anterosuperior humeral subluxa-
tion in the rotator cuff deficient shoulder. Orthop Trans
1996;21:229.
56 Fagelman M, Sartori M, Freedman KB, Patwardhan AG,
Carandang G, Marra G. Biomechanics of coracoacromial
arch modification. J Shoulder Elbow Surg 2007;16:101–6.
57 Chen J, Luo CF, Luo ZP. Initiatory biomechanical study on
humeral head migration after coracoacromial ligament cut.
Arch Orthop Trauma Surg 2009;129:133–7.
58 Harryman DT, 2nd, Lazarus MD, Yung SW, Sidles JA,
Matsen FA. Anterosuperior humeral displacement: limitation
by the coracoacromial arch. J Shoulder Elbow Surg
1996;5:S29.
59 Su WR, Budoff JE, Luo ZP. The effect of coracoacromial
ligament excision and acromioplasty on superior and ante-
rosuperior glenohumeral stability. Arthroscopy 2009;25:13–8.
60 Samuelsson K, Andersson D, Karlsson J. Treatment of
anterior cruciate ligament injuries with special reference to
graft type and surgical technique: an assessment of rando-
mized controlled trials. Arthroscopy 2009;25:1139–74.
61 Hockman DE, Lucas GL, Roth CA. Role of the coracoacro-
mial ligament as restraint after shoulder hemiarthroplasty.
Clin Orthop Relat Res 2004;419:80–2.
62 Ayub E. Posture and the upper quarter. In: Donatelli R,
editor. Physical therapy of the shoulder. 2nd ed. Melbourne:
Churchill Livingstone; 1991. p. 81–90.
63 Grimsby O, Gray J. Interrelation of the spine to the shoulder
girdle. In: Donatelli R, editor.Physical therapy of the shoulder.
3rd ed. New York: Churchill Livingstone; 1997. p. 95–129.
64 Gray J, Grimsby O. Interrelationship of the spine, rib cage,
and shoulder. In: Donatelli R, editor. Physical therapy of the
shoulder. 4th ed. Edinburgh: Churchill Livingston; 2004.
p. 133–85.
65 Ludewig PM, Cook TM. Alterations in shoulder kinematics
and associated muscle activity in people with symptoms of
shoulder impingement. Phys Ther 2000;80:276–91.
66 Kebaetse M, McClure P, Pratt NA. Thoracic position effect
on shoulder range of motion, strength, and three-dimensional
scapular kinematics. Arch Phys Med Rehabil 1999;80:945–50.
67 Sahrmann S. Diagnosis and treatment of movement impair-
ment syndromes. London: Mosby; 2002. p. 193–261.
68 Bullock MP, Foster NE, Wright CC. Shoulder impingement:
the effect of sitting posture on shoulder pain and range of
motion. Man Ther 2005;10:28–37.
69 Lewis JS. Rotator cuff tendinopathy/subacromial impinge-
ment syndrome: is it time for a new method of assessment? Br
J Sports Med 2009;43:259–64.
70 Lewis JS, Green A, Wright C. Subacromial impingement
syndrome: the role of posture and muscle imbalance.
J Shoulder Elbow Surg 2005;14:385–92.
71 Lewis JS, Valentine RE. The pectoralis minor length test: a
study of the intra-rater reliability and diagnostic accuracy in
subjects with and wit hout shoulder symptoms. BMC
Musculoskelet Disord 2007;8:64.
72 Grimmer K. An investigation of poor cervical resting posture.
Aust J Physiother 1997;43:7–16.
73 McClure PW, Bialker J, Neff N, Williams G, Karduna A.
Shoulder function and 3-dimensional kinematics in people
with shoulder impingement syndrome before and after a 6-
week exercise program. Phys Ther 2004;84:832–48.
74 Griegel-Morris P, Larson K, Mueller-Klaus K, Oatis CA.
Incidence of common postural abnormalities in the cervical,
shoulder, and thoracic regions and their association with pain
in two age groups of healthy subjects. Phys Ther 1992;72:425–
31.
75 Lederman E. The fall of the postural-structural-biomechanical
model in manual and physical therapies: Exemplified by lower
back pain. J Bodyw Mov Ther 2011;15:131–8.
76 Raine S, Twomey LT. Head and shoulder posture variations
in 160 asymptomatic women and men. Arch Phys Med
Rehabil 1997;78:1215–23.
77 Singer KP, Goh S. Anatomy of the thoracic spine. In: Giles
LGF, Singer KP, editors. The clinical anatomy and manage-
ment of thoracic spine pain. Vol 2. Oxford: Butterworth
Heinemann; 2000. p. 17–33.
78 Lewis JS, Valentine RE. Clinical measurement of the thoracic
kyphosis. A study of the intra-rater reliability in subjects with
and without shoulder pain. BMC Musculoskelet Disord
2010;11:39.
79 Fukuda H, Hamada K, Yamanaka K. Pathology and
pathogenesis of bursal-side rotator cuff tears viewed from en
bloc histologic sections. Clin Orthop Relat Res 1990;254:75–
80.
80 Sarkar K, Uhthoff HK. Ultrastructure of the subacromial
bursa in painful shoulder syndromes. Virchows Arch A Pathol
Anat Histopathol 1983;400:107–17.
81 Santavirta S, Konttinen YT, Antti-Poika I, Nordstrom D.
Inflammation of the subacromial bursa in chronic shoulder
pain. Arch Orthop Trauma Surg 1992;111:336–40.
82 Standring S. Gray’s Anatomy. 39th ed. Edinburgh: Elsevier
Churchill Livingstone; 2005. p. 817–49.
83 Aszmann OC, Dellon AL, Birely BT, McFarland EG.
Innervation of the human shoulder joint and its implications
for surgery. Clin Orthop Relat Res 1996;330:202–7.
84 Ide K, Shirai Y, Ito H, Ito H. Sensory nerve supply in the
human subacromial bursa. J Shoulder Elbow Surg 1996;5:371–
82.
85 Gotoh M, Ha mada K, Yamakawa H, Yanagisawa K,
Nakamura M, Yamazaki H, et al. Interleukin-1-induced
subacromial synovitis and shoulder pain in rotator cuff
diseases. Rheumatology (Oxford) 2001;40:995–1001.
Physical Therapy Reviews ptr7245.3d 18/7/11 17:44:27
The Charlesworth Group, Wakefield +44(0)1924 369598 - Rev 7.51n/W (Jan 20 2003)
Lewis Subacromial impingement syndrome
10 Physical Therapy Reviews 2011 VOL.000 NO.000
86 Gotoh M, Hamada K, Yamakawa H, Inoue A, Fukuda H.
Increased substance P in subacromial bursa and shoulder pain
in rotator cuff diseases. J Orthop Res 1998;16:618–21.
87 Gotoh M, Ha mada K, Yamakawa H, Yanagisawa K,
Nakamura M, Yamazaki H, et al. Interleukin-1-induced
glenohumeral synovitis and shoulder pain in rotator cuff
diseases. J Orthop Res 2002;20:1365–71.
88 Sakai H, Fujita K, Sakai Y, Mizuno K. Immunolocalization
of cytokines and growth factors in subacromial bursa of
rotator cuff tear patients. Kobe J Med Sci 2001;47:25–34.
89 Yanagisawa K, Hamada K, Gotoh M, TokunagaT, Oshika Y,
Tomisawa M, et al. Va scular endothelial growth factor
(VEGF) expression in the subacromial bursa is increased in
patients with impingement syndrome. J Orthop Res
2001;19:448–55.
90 Hyvonen P, Melkko J, Lehto VP, Jalovaara P. Involvement of
the subacrom ial bursa in impingement syndrome of the
shoulder as judged by expression of tenascin-C and histo-
pathology. J Bone Joint Surg Br 2003;85:299–305.
91 Voloshin I, Gelinas J, Maloney MD, O’Keefe RJ, Bigliani LU,
Blaine TA. Proinflammatory cytokines and metalloproteases
are expressed in the subacromial bursa in patients with rotator
cuff disease. Arthroscopy 2005;21:1076.
92 Henkus HE, de Witte PB, Nelissen RG, Brand R, van Arkel
ER. Bursectomy compared with acromioplasty in the manage-
ment of subacromial impingement syndrome: a prospective
randomised study. J Bone Joint Surg Br 2009;91:504–10.
93 Henkus HE, Cobben LP, Coerkamp EG, Nelissen RG, van
Arkel ER. The accuracy of su bacromial injections: a
prospective randomized magnetic resonance imaging study.
Arthroscopy 2006;22:277–82.
94 Naredo E, Cabero F, Beneyto P, Cruz A, Mondejar B, Uson J,
et al. A randomized comparative study of short term response
to blind injection versus sonographic-guided injection of local
corticosteroids in patients with painful shoulder. J Rheumatol
2004;31:308–14.
95 Chen MJ, Lew HL, Hsu TC, Tsai WC, Lin WC, Tang SF,
et al. Ultrasound-guided shoulder injections in the treatment
of subacromial bursitis. Am J Phys Med Rehabil 2006;85:31–
5.
96 Alvarez CM, Litchfield R, Jackowski D, Griffin S, Kirkley A.
A prospective, double-blind, randomized clinical trial compar-
ing subacromial injection of betamethasone and xylocaine to
xylocaine alone in chronic rotator cuff tendinosis. Am J Sports
Med 2005;33:255–62.
97 Akgun K, Birtane M, Akarirmak U. Is local subacromial
corticosteroid injection beneficial in subacromial impingement
syndrome? Clin Rheumatol 2004;23:496–500.
98 Plafki C, Steffen R, Willburger RE, Wittenberg RH. Local
anaesthetic injection with and without corticosteroids for
subacromial impingement syndrome. Int Orthop 2000;24:40–
2.
99 Ekeberg OM, Bautz-Holter E, Tveita EK, Juel NG, Kvalheim S,
Brox JI. Subacromial ultrasound guided or systemic steroid
injection for rotator cuff disease: randomised double blind
study. BMJ 2009;338:273–6.
100 Burns TP, Turba JE. Arthroscopic treatment of shoulder
impingement in athletes. Am J Sports Med 1992;20:13–6.
101 Checroun AJ, Dennis MG, Zuckerman JD. Open versus
arthroscopic decompression for subacromial impingement. A
comprehensive review of the literature from the last 25 years.
Bull Hosp Jt Dis 1998;57:145–51.
102 Ellman H, Kay SP. Arthroscopic subacromial decompression
for chronic impingement. Two- to five-year results. J Bone
Joint Surg Br 1991;73:395–8.
103 Chin PY, Sperling JW, Cofield RH, Stuart MJ, Crownhart
BS. Anterior acromioplasty for the shoulder impingement
syndrome: long-term outcome. J Shoulder Elbow Surg
2007;16:697–700.
104 McClelland D, Paxinos A, Dodenhoff RM. Rate of return to
work and driving following arthroscopic subacromial decom-
pression. ANZ J Surg 2005;75:747–9.
105 Charalambous CP, Sahu A, Alvi F, Batra S, Gullett TK,
Ravenscroft M. Return to work an d driving following
arthroscopic subacromial decompression and acromio-clavi-
cular joint excision. Shoulder Elbow 2010;2:83–6.
106 Moseley JB, O’Malley K, Petersen NJ, Menke TJ, Brody BA,
Kuykendall DH, et al. A controlled trial of arthroscopic
surgery for osteoarthritis of the knee. N Engl J Med
2002;347:81–8.
107 Dimond EG, Kittle CF, Crockett JE. Comparison of internal
mammary artery ligation and sham operation for angina
pectoris. Am J Cardiol 1960;5:483–6.
108 Cobb LA, Thomas GI, Dillard DH, Merendino KA, Bruce
RA. An evaluation of internal-mammary-artery ligation by a
double-blind technic. N Engl J Med 1959;260:1115–8.
109 Hawkins RJ, Kennedy JC. Impingement syndrome in athletes.
Am J Sports Med 1980;8:151–8.
110 Zaslav KR. Internal rotation resistance strength test: a new
diagnostic test to differentiate intra-articular pathology from
outlet (Neer) impingement syndrome in the shoulder.
J Shoulder Elbow Surg 2001;10:23–7.
111 Lewis JS, Tennent TD. How effective are diagnostic tests for
the assessment of rotator cuff disease of the shoulder? In:
MacAuley D, Best TM, editors. Evidenced based sports
medicine. 2nd ed. London: Blackwell Publishing; 2007. p. 327–
59.
112 Hegedus EJ, Goode A, Campbell S, Morin A, Tamaddoni M,
Moorman CT, 3rd, et al. Physical examination tests of the
shoulder: a systematic review with meta-analysis of individual
tests. Br J Sports Med 2008;42:80–92.
113 Schellingerhout JM, Verhagen AP, Thomas S, Koes BW. Lack
of uniformity in diagnostic labeling of shoulder pain: time for
a different approach. Man Ther 2008;13:478–83.
114 Sher JS, Uribe JW, Posada A, Murphy BJ, Zlatkin MB.
Abnormal findings on magnetic resonance images of asympto-
matic shoulders. J Bone Joint Surg Am 1995;77:10–5.
115 Milgrom C, Schaffler M, Gilbert S, van Holsbeeck M.
Rotator-cuff changes in asymptomatic adults. The effect of
age, hand dominance and gender. J Bone Joint Surg Br
1995;77:296–8.
116 Frost P, Andersen JH, Lundorf E. Is supraspinatus pathology
as defined by magnetic resonance imaging associated with
clinical sign of shoulder impingement? J Shoulder Elbow Surg
1999;8:565–8.
117 Dillman CJ, Fleisig GS, Andrews JR. Biomechanics of
pitching with emphasis upon shoulder kinematics. J Orthop
Sports Phys Ther 1993;18:402–8.
118 Feltner M. Three-dimensional interactions in a two-segment
kinetic chain. Part II: application to the throwing arm in
baseball pitching. Int J Sports Biomech 1989;5:420–50.
119 Miniaci A, Mascia AT, Salonen DC, Becker EJ. Magnetic
resonance imaging of the shoulder in asymptomatic profes-
sional baseball pitchers. Am J Sports Med 2002;30:66–73.
120 Connor PM, Banks DM, Tyson AB, Coumas JS,
D’Alessandro DF. Magnetic reson ance imaging of t he
asymptomatic shoulder of overhead athletes: a 5-year follow-
up study. Am J Sports Med 2003;31:724–7.
121 Smith C, Deans V, Drew S. The sourcil sign: a useful finding
on plain x-ray? Shoulder Elbow 2010;2:9–12.
122 Lewis JS, Raza SA, Pilcher J, Heron C, Poloniecki JD. The
prevalence of neovascularity in patients clinically diagnosed
with rotator cuff tendinopathy. BMC Musculoskelet Disord
2009;10:163.
123 Brox JI, Staff PH, Ljunggren AE, Brevik JI. Arthroscopic
surgery compared with supervised exercises in patients with
rotator cuff disease (stage II impingement syndrome). BMJ
1993;9:899–903.
124 Soslowsky LJ, Thomopoulos S, Esmail A, Flanagan CL,
Iannotti JP, Williamson JD, 3rd, et al. Rotator cuff tendinosis
in an animal model: role of extrinsic and overuse factors. Ann
Biomed Eng 2002;30:1057–63.
125 Cook JL, Purdam CR. Is tendon pathology a continuum? A
pathology model to explain the clinical presentation of load-
induced tendinopathy. Br J Sports Med 2009;43:409–16.
126 Scott A, Cook JL, Hart DA, Walker DC, Duronio V, Khan
KM. Tenocyte responses to mechanical loading in vivo: a role
for local insulin-like growth factor 1 signaling in early
tendinosis in rats. Arthritis Rheum 2007;56:871–81.
127 Corps AN, Robinson AH, Movin T, Costa ML, Hazleman
BL, Riley GP. Increased expression of aggrecan and biglycan
mRNA in Achilles tendinopathy. Rheumatology (Oxford)
2006;45:291–4.
128 Riley G. Tendinopathy–from basic science to treatment. Nat
Clin Pract Rheumatol 2008;4:82–9.
129 Tsai WC, Tang FT, Hsu CC, Hsu YH, Pang JH, Shiue CC.
Ibuprofen inhibition of tendon cell proliferation and upregu-
lation of the cyclin kinase inhibitor p21CIP1. J Orthop Res
2004;22:586–91.
Physical Therapy Reviews ptr7245.3d 18/7/11 17:44:27
The Charlesworth Group, Wakefield +44(0)1924 369598 - Rev 7.51n/W (Jan 20 2003)
Lewis Subacromial impingement syndrome
Physical Therapy Reviews 2011
VOL. 000 NO.000 11
130 Scutt N, Rolf CG, Scutt A. Glucocorticoids inhibit tenocyte
proliferation and Tendon progenitor cell recruitment.
J Orthop Res 2006;24:173–82.
131 Ainsworth R, Lewis JS, Conboy V. A prospective randomized
placebo controlled clinical trial of a rehabilitation programme
for patients with a diagnosis of massive rotator cuff tears of
the shoulder. Shoulder Elbow 2009;1:55–60.
132 Yiasemides R, Halaki M, Cathers I, Ginn KA. Does passive
mobilization of shoulder region joints provide additional
benefit over advice and exercise alone for people who have
shoulder pain and minimal movement restriction? A rando-
mized controlled trial. Phys Ther 2011;91:178–89.
133 Bang MD, Deyle GD. Comparison of supervised exercise with
and without manual physical therapy for patients with
shoulder impingement syndrome. J Orthop Sports Phys Ther
2000;30:126–37.
134 McClatchie L, Laprade J, Martin S, Jaglal SB, Richardson D,
Agur A. Mobilizations of the asymptomatic cervical spine can
reduce signs of shoulder dysfunction in adults. Man Ther
2009;14:369–74.
Physical Therapy Reviews ptr7245.3d 18/7/11 17:44:28
The Charlesworth Group, Wakefield +44(0)1924 369598 - Rev 7.51n/W (Jan 20 2003)
Lewis Subacromial impingement syndrome
12 Physical Therapy Reviews 2011 VOL.000 NO.000
... If there is not enough space, these soft tissues can become pinched. This is called SAIS or otherwise rotator cuff impingement syndrome (Lewis 2008), shoulder impingement syndrome, painful arc syndrome (Hanchard et al 2004), and subacromial pain syndrome (Lewis 2011). Therefore, SAIS is a collection of soft tissue pathologies rather than a specific pathology (Lewis 2008). ...
... The impact of shoulder pain on the economy is high because the cost involved in its management is huge (Lewis 2011). Using figures from a comprehensive evaluation of shoulder disorders (Garg et al 2010) Arthritis Research UK, has estimated the cost of shoulder pain in the general population to be in the region of £100 million. ...
... Since the introduction of injection therapy by the CSP in 1995, many of these ESPs provide soft tissue and joint injections to patients with musculoskeletal pain such as SAIS (Lewis 2011). In today's current healthcare climate, where GPs and funding providers fund two or three treatment sessions, notwithstanding the condition or needs of the patient, cortisone injection is even more relevant. ...
... At a 3-month follow-up, Struyf et al. [18] found maintenance of the effects of a scapular-focused treatment in patients with RCS. Given the increasing body of evidence from studies demonstrating no increased clinical benefit from surgery compared with exercise [69], it seems reasonable that patients with RCS or ASI associated shoulder pain and dysfunction should undergo a conservative trial of rehabilitation before considering surgical options. In the current study, only 29 patients (15.8%) had a recurrence episode (new symptoms due to the same problem that brought them to physiotherapy in the first place). ...
... The results of this study support other research [13,27,40,[69][70][71][72][73]] that a progressive scapular-focused approach incorporating feedback and home management can significantly reduce pain and increase function in RCS and ASI associated shoulder pain. Whether the specific attention is to motor control, in particular, SSNC requires further research. ...
Article
Full-text available
Current clinical practice lacks consistent evidence in the management of scapular dyskinesis. This study aims to determine the short- and long-term effects of a scapular-focused exercise protocol facilitated by real-time electromyographic biofeedback (EMGBF) on pain and function, in individuals with rotator cuff related pain syndrome (RCS) and anterior shoulder instability (ASI). One-hundred and eighty-three patients were divided into two groups (n = 117 RCS and n = 66 ASI) and guided through a structured exercise protocol, focusing on scapular dynamic control. Values of pain and function (shoulder pain and disability index (SPADI) questionnaire, complemented by the numeric pain rating scale (NPRS) and disabilities of the arm, shoulder, and hand (DASH) questionnaire) were assessed at the initial, 4-week, and 2-year follow-up and compared within and between. There were significant differences in pain and function improvement between the initial and 4-week assessments. There were no differences in the values of DASH 1st part and SPADI between the 4-week and 2-year follow-up. There were no differences between groups at the baseline and long-term, except for DASH 1st part and SPADI (p < 0.05). Only 29 patients (15.8%) had a recurrence episode at follow-up. These results provide valuable information on the positive results of the protocol in the short- and long-term.
... RCRSP constitutes a major cause for shoulder pain, chronicity of which can lead to significant limitation of upper limb function [39,40]. Exercises form an integral part of the management and rehabilitation of these patients. ...
Article
Background: Numerous studies have established bilateral changes that underpin a reorganization of the central nervous system in individuals with unilateral tendinopathy. The evidence for sensory and motor profiles of the contralateral limb and neuroplastic (cortical) changes have not been specifically reviewed for rotator cuff related shoulder pain (RCRSP). Objectives: To systematically review, summarize and appraise the evidence for sensory and motor profiles of the contralateral (non-injured) upper limb and neuroplastic changes in individuals with unilateral RCRSP. Methods: This review will follow the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) statement and the guidelines for performing a Meta-analysis and Systematic Review of Observational Studies in Epidemiology (MOOSE). Two reviewers will screen, appraise, and extract the data using a customized data extraction tool, and synthesize findings from all studies irrespective of their methodological quality. The methodologic-ally quality of the included studies will be assessed using a modified Downs and Black index. Statistical and clinical heterogeneity associated with the outcomes of interest will be assessed, and a meta-analysis will be done if appropriate. The certainty of evidence will be synthesized using the Grading of Recommendations, Assessment, Development and Evaluation (GRADE). Discussion: Previous studies indicate a reorganization of the nervous system with chronic musculoskeletal pain. If bilateral sensory/motor impairments or neuroplastic changes are evident in individuals with unilateral RCRSP, interventions may need to be tailored to include bilateral impairments as well as interventions that consider neuroplasticity.
... The most frequent clinical diagnosis is subacromial pain syndrome (Lewis, 2011). Extensive literature is generated around this syndrome. ...
Article
Background Serratus anterior strengthening generally appears in shoulder rehabilitation protocols. This study's aim was to measure electromyographic activity of the serratus anterior, upper trapezius, and infraspinatus muscles during the Supine Scapular Punch exercise in healthy volunteers and those with unilateral shoulder pain. Methods Fifty-four participants were included and grouped as without (n = 34, age = 25.8 years) or with unilateral shoulder pain (n = 20, age = 26.3 years, visual analogue scale = 4.15 cm). Electromyographic activity of the serratus anterior, upper trapezius, and infraspinatus muscles was assessed during Supine Scapular Punch (four phases: P1 = press up concentric, P2 = Supine Scapular Punch concentric, P3 = Supine Scapular Punch eccentric, P4 = press up eccentric) performed under two conditions, with and without additional load. Findings Overall muscle activity during P1 and P4 was negligible (< 10% maximal voluntary isometric contractions). During P2 and P3, no statistically significant differences in serratus anterior and upper trapezius muscle activity were found between groups, with moderate to high serratus anterior activity (28.94% to 44.3%) and very low upper trapezius activity (< 6%). Upper trapezius/serratus anterior activity ratios ranged from 0.09 to 0.18. Overall infraspinatus muscle activity was always very low (< 10%). Interpretation The Supine Scapular Punch induces moderate to high serratus anterior muscle activity with very low upper trapezius and infraspinatus activation. Based on these results, the Supine Scapular Punch is a safe exercise that can be used in the early phases of shoulder rehabilitation.
... Despite this limited understanding, there is a growing body of evidence supporting the use of exercise to manage AT (Coombes et al., 2013;Lewis, 2013;Magnussen et al., 2009), and exercise is recommended first-line care in practice and expert consensus (Martin et al., 2018;Scott et al., 2013;Van Der Vlist et al., 2021). Interestingly, variation in exercise approach does not appear to significantly impact outcome, with no single approach demonstrating superiority over another (Beyer et al., 2015;Malliaras et al., 2013;Van Der Vlist et al., 2021). ...
Article
Background . Achilles tendinopathy (AT) is common, and can be traumatic or insidious in onset and short-lasting or persistent in nature. Factors influencing the experience of pain are poorly understood; little is known about mechanisms driving pain and the response (or lack of) to rehabilitation. Despite this, there is a growing body of evidence supporting the use of exercise to manage AT. Interestingly, variation in exercise approach does not appear to significantly impact outcome. Patients’ perceptions of factors related to rehabilitation that may influence outcome could provide a valuable addition to help guide future research and practice. Objectives . The aim of this study is to gain an insight into patients’ experiences of participating in an exercise-based rehabilitation programme for AT. Method . A qualitative interpretive description design. Data generated from semi-structured interviews were analysed thematically using the guidelines set out by Braun and Clarke. Findings . This is the first study to use a qualitative method of inquiry to gain data on the experiences of people undertaking exercise-based rehabilitation for AT. The four major themes that were identified from the data were: (1) ‘understanding the impact’ (2) ‘expectations’ (3) ‘what matters’ and (4) ‘the burden of exercise’. Conclusions . Given the uncertainty surrounding the mechanisms of effect of our treatments, the insights provide a platform from which researchers and clinicians can consider further in the management of people with Achilles tendinopathy. Specifically, it has highlighted that patients value a flexible, supportive approach embracing the biopsychosocial impact of AT on the individual.
... Today, some four decades after the publication of Neer's proposition and despite its comprehensive refutation, belief in "impingement syndrome" as a real clinical entity remains intact (42,45,46). The acceptance of Neer's assumptions by orthopedic surgeons as established knowledge has led to "sub-acromial decompression, which became one of the most commonly performed shoulder operations globally (approximately 21,000 decompression procedures per year in the United Kingdom and many times more in the United States), although it has been shown to be no more beneficial than placebo (47). ...
Article
Full-text available
In this paper we attempt to explain the problems that can arise when assumptions made by experts in their respective fields of Medicine become widely accepted as established knowledge. Our hypothesis is that these problems are in large part attributable to a failure of the experts to follow the principles of logical argument. Empirical data to evaluate our hypothesis derives from an analysis of the reasoning processes employed in the generation of three syndromes drawn from the clinical discipline of Pain Medicine: myofascial pain, shoulder impingement and central sensitisation. We demonstrate a failure by the proponents of these syndromes to structure their scientific arguments in a logically valid fashion, which lead them to promote assumptions to the status of facts. In each instance those in relevant scientific journals responsible for content review accepted – and thereby promulgated - this fundamental error in reasoning. The wide acceptance of each of these assumptions as established knowledge affirms our hypothesis. Furthermore, we show that such uncritical acceptance has had significant consequences for many patients.
Article
Background The rotator cuff is a group of muscles and tendons which support the shoulder joint. Rotator cuff disease is a frequent cause of morbidity in adulthood. Aims The aims of his study are to determine the prevalence and patterns of rotator cuff derangement in symptomatic patients using MRI and to attempt to correlate identified patterns of disease with age and gender Methods Five hundred ninety-seven patients attending for MRI of the shoulder with atraumatic shoulder pain were included for study. Patients’ age and gender was recorded. Record was made of the presence or absence of rotator cuff derangement and of degenerative change in the AC and glenohumeral joints. Correlation was made between age and gender. Results There were 358 males (60%) and 239 females (40%) with a mean age of 49.4 ± 17.1 years. Subacromial bursitis was identified in 517 patients. A normal supraspinatus tendon was identified in 219 patients and supraspinatus full thickness tearing was identified in 102 patients. A normal AC joint was identified in 267 patients while degenerative AC joint changes were identified in 370 patients. A significant correlation was identified between age and rotator cuff derangement ( p < .001) and between age and AC joint derangement ( p < .001). No significant difference was identified between gender and patterns of cuff derangement Conclusion The extent of rotator cuff and AC joint derangement increases with ageing. Impingement appears to trigger a cascade of events in sequence, from isolated subacromial bursitis through to supraspinatus tendon tearing. Patterns of rotator cuff derangement are similar in men and women.
Preprint
Full-text available
Background: Assessment of shoulder proprioception outside the laboratory in the absence of specialized equipment remains a challenge with field-based tests often lacking good reliability, validity and feasibility. This study aimed to enhance the knowledge base surrounding the assessment of shoulder proprioception and investigated the effect of fatigue on shoulder joint position sense (JPS) amongst amateur male handball players. Method: 27 healthy recreationally active participants and 13 amateur male handball players undertook two sessions of active JPS tests using laser pen technology and a calibrated 2-dimensional target to assess test-retest reliability. The active JPS test was then utilized on the subgroup of handball players who were subjected to five bouts of a repeated throwing task in order to investigate the effect of local fatigue on shoulder JPS. Results: The intraclass correlation coefficient for the active JPS test was 0.78 (95% CI = [0.57; 0.89]). Standard error of measurement between trials was 0.70° (range 0.57°-0.90°). For the throwing task, repeated measures analysis of variance revealed a significant interaction for arm x bout (F5=2.74, p=0.028) and a significant effect for arm (F1=5.85, p=0.034). Post hoc analysis showed a significant difference between throwing arm and non-throwing arm after throwing bout one (p=0.036), three (p=0.026) and four (p=0.041). Conclusion: Assessment of the active JPS test showed acceptable reliability and measurement error. Repeated throwing to fatigue decreased shoulder JPS in amateur male handball players which indicate validity of the test to identify reduced proprioception.
Chapter
Dit hoofdstuk begint met een uiteenzetting over de myofasciale bindweefselplaatsystemen in en rond de schouder en de belangrijke rol van het losmazig reticulaire MCDAS. Naast het glenohumerale systeem (HSMI) is er ruime aandacht voor het primaire en secundaire scapulothoracale systeem. Na de beschrijving van de descriptieve anatomie en de osteo- en artrokinematica komen veelvoorkomende aandoeningen als schouderinstabiliteit, het SubAcromiale PijnSyndroom (SAPS) en de frozen shoulder (inclusief de SNN-praktijkrichtlijn frozen shoulder 2017) aan bod. De rode vlaggen worden besproken en er wordt uitgebreid stilgestaan bij aspecifieke schouderpijn (‘medisch onbegrepen’ pijn). In het kader van het lichamelijk onderzoek staan nu – in plaats van provocatietests – de reductietests centraal, zoals de Combined Reduction Test (of: ‘Manus-van-alles’-techniek), de gedupliceerde circumductie- en deviatiebeweging, SAT, SRT, GHRT en de SSMP. De bekende provocatietests met hoge sensitiviteit hebben nog slechts excluderende waarde bij een negatieve uitkomst. Tot slot presenteren de auteurs als schouderexperts – naast een handige ‘patronenmatrix’ – het fundament voor onderzoek- en behandelprotocollen bij aspecifieke en mild specifieke schouderpijn. Er worden 78 onderzoeks- en behandeltechnieken van de schoudergordel uitgebreid beschreven en op video gedemonstreerd. De thoracale, cervicothoracale én cervicale wervelkolomtechnieken komen uitgebreid aan bod in de H. 10.1007/978-90-368-2255-8_10, 10.1007/978-90-368-2255-8_11 en 10.1007/978-90-368-2255-8_12.
Article
Subacromial decompression was performed arthroscopically on 65 patients who were evaluated two to five years after the procedure. None had full thickness rotator cuff tears. Patients with partial thickness cuff tears were included in this study in order to allow comparison of arthroscopic acromioplasty with open acromioplasty for stage II impingement. On the UCLA shoulder rating scale, 89% of the cases in this study achieved a satisfactory result. These results compare favourably with those reported following open acromioplasty. The arthroscopic procedure is technically demanding. When properly performed in patients with appropriate indications, hospitalisation is brief, return to activities is rapid, there is little risk of deltoid muscle complications, and the results are lasting.
Article
Background: Diagnoses and treatments based on movement system impairment syndromes were developed to guide physical therapy treatment. Objectives: This masterclass aims to describe the concepts on that are the basis of the syndromes and treatment and to provide the current research on movement system impairment syndromes. Results: The conceptual basis of the movement system impairment syndromes is that sustained alignment in a non-ideal position and repeated movements in a specific direction are thought to be associated with several musculoskeletal conditions. Classification into movement system impairment syndromes and treatment has been described for all body regions. The classification involves interpreting data from standardized tests of alignments and movements. Treatment is based on correcting the impaired alignment and movement patterns as well as correcting the tissue adaptations associated with the impaired alignment and movement patterns. The reliability and validity of movement system impairment syndromes have been partially tested. Although several case reports involving treatment using the movement system impairment syndromes concept have been published, efficacy of treatment based on movement system impairment syndromes has not been tested in randomized controlled trials, except in people with chronic low back pain.
Article
Patients with an irreparable rotator cuff tear and glenohumeral degeneration often are treated with hemiarthroplasty. This procedure has proven effective as long as the coracoacromial ligament remained intact. The ligament reportedly acts as a restraint against anterosuperior dislocation. The purpose of the current study was to test the role of the coracoacromial ligament as an anterosuperior restraint after hemiarthroplasty in shoulders from cadavers with simulated irreparable rotator cuff tears. Six fresh-frozen shoulders were dissected to mimic a massive rotator cuff tear. After a hemiarthroplasty was done, each shoulder was mounted in a fixture, which was attached to a materials testing device. Using this device, the role of the coracoacromial ligament was evaluated by loading the shoulders in various positions and then measuring displacement before and after excision of the ligament. The mean difference in anterosuperior displacement was 3.44 mm. In all shoulders, subjective observation revealed that the humeral head often becomes wedged between the coracoid and the acromion during axial loading after excision of the coracoacromial, ligament. Therefore, the coracoacromial ligament should be preserved to enhance the stability of the joint and to preserve the superior fulcrum.