Does a Positive Neer Impingement Sign Reflect Rotator Cuff Contact with the Acromion?
One possible cause of shoulder pain is rotator cuff contact with the superior glenoid (cuff-glenoid contact) with the arm in flexion, as occurs during a Neer impingement sign. It has been assumed that the pain with a Neer impingement sign on physical examination of the shoulder was secondary to the rotator cuff making contact with the anterior and lateral acromion. We determined if the arm position where pain occurs with a Neer impingement sign would correlate with the position where the rotator cuff made contact with the superior glenoid, as determined by arthroscopic evaluation. We prospectively studied 398 consecutive patients with a positive Neer impingement sign during office examination and used a handheld goniometer to measure (in degrees of flexion) the arm position in which impingement pain occurred. During subsequent arthroscopy, the arm was moved into a similar position, and we measured the arm's position in flexion at the point the rotator cuff made contact with the superior glenoid using a handheld goniometer. We compared the degrees of flexion at which pain occurred preoperatively and at which there was cuff-glenoid contact. Among the 398 patients, 302 (76%) had arthroscopically documented cuff-glenoid contact, whereas 96 did not. For the 302 patients with a positive Neer sign preoperatively and with arthroscopically documented cuff-glenoid contact, the average preoperative impingement pain position was 120.1°±26.7°, similar to that of the average intraoperative cuff-glenoid contact position of 120.6°±14.7°. Our data suggest pain associated with a positive Neer sign more often relates to contact of the rotator cuff with the superior glenoid than to contact between the rotator cuff and acromion. Level II, prognostic study. See Guidelines for Authors for a complete description of levels of evidence.
Does a Positive Neer Impingement Sign Reﬂect Rotator Cuff
Contact with the Acromion?
Xiaofeng Jia MD, PhD, Jong Hun Ji MD,
Vinodhkumar Pannirselvam MD, Steve A. Petersen MD,
Edward G. McFarland MD
Received: 28 January 2010 / Accepted: 10 September 2010 / Published online: 28 September 2010
Ó The Association of Bone and Joint Surgeons1 2010
Background One possible cause of shoulder pain is
rotator cuff contact with the superior glenoid (cuff-glenoid
contact) with the arm in ﬂexion, as occurs during a Neer
impingement sign. It has been assumed that the pain with a
Neer impingement sign on physical examination of the
shoulder was secondary to the rotator cuff making contact
with the anterior and lateral acromion.
Questions/purposes We determined if the arm position
where pain occurs with a Neer impingement sign would
correlate with the position where the rotator cuff made
contact with the superior glenoid, as determined by
Patients and Methods We prospectively studied 398
consecutive patients with a positive Neer impingement sign
during ofﬁce examination and used a handheld goniometer
to measure (in degrees of ﬂexion) the arm position in which
impingement pain occurred. During subsequent arthros-
copy, the arm was moved into a similar position, and we
measured the arm’s position in ﬂexion at the point the
rotator cuff made contact with the superior glenoid using a
handheld goniometer. We compared the degrees of ﬂexion
at which pain occurred preoperatively and at which there
was cuff-glenoid contact.
Results Among the 398 patients, 302 (76%) had arthro-
scopically documented cuff-glenoid contact, whereas 96
did not. For the 302 patients with a positive Neer sign
preoperatively and with arthroscopically documented cuff-
glenoid contact, the average preoperative impingement
pain position was 120.1° ± 26.7°, similar to that of the
average intraoperative cuff-glenoid contact position of
120.6° ± 14.7°.
Conclusions Our data suggest pain associated with a
positive Neer sign more often relates to contact of the
rotator cuff with the superior glenoid than to contact
between the rotator cuff and acromion.
Level of Evidence Level II, prognostic study. See
Guidelines for Authors for a complete description of levels
Impingement syndrome was described by Dr. Charles
Neer II in 1972  as a spectrum of disease of the rotator
cuff resulting from rotator cuff degeneration and
impingement of the rotator cuff on the acromion and cor-
acoacromial arch. Clinically, this syndrome was
characterized by pain in the shoulder and proximal arm
anteriorly and laterally with elevation of the arm. Neer [27,
28] described a diagnostic sign for impingement performed
by passively ﬂexing the patient’s arm until pain is felt in
the anterior or anterolateral proximal arm. According to
Bigliani and Levine , a positive impingement sign
Each author certiﬁes that he has no commercial associations (eg,
consultancies, stock ownership, equity interest, patent/licensing
arrangements, etc) that might pose a conﬂict of interest in connection
with the submitted article.
Each author certiﬁes that his or her institution has approved the
human protocol for this investigation and that all investigations were
conducted in conformity with ethical principles of research.
X. Jia, J. H. Ji, V. Pannirselvam, S. A. Petersen, E. G. McFarland
Division of Shoulder Surgery, Department of Orthopaedic
Surgery, The Johns Hopkins University, Baltimore, MD, USA
E. G. McFarland (&)
c/o Elaine P. Henze, BJ, ELS, Medical Editor and Director,
Editorial Services, Department of Orthopaedic Surgery, Johns
Hopkins Bayview Medical Center, 4940 Eastern Avenue,
#A665, Baltimore, MD 21224-2780, USA
e-mail: email@example.com; firstname.lastname@example.org
Clin Orthop Relat Res (2011) 469:813–818
typically occurs with the arm between 70° and 120° ﬂex-
ion. This ‘Neer sign’ has been considered an important
diagnostic indicator for rotator cuff impingement [22, 28].
It has been suggested impingement pain may occur as a
result of contact between the rotator cuff and the superior
glenoid (hereinafter termed ‘‘cuff-glenoid contact’’) .
Cuff-glenoid contact has been observed with the arm in
abduction and external rotation (called ‘‘internal impinge-
ment’’) and with the arm in forward ﬂexion (called ‘‘ﬂexion
contact’’) [7, 18, 38]. Cuff-glenoid contact with the arm in
abduction and external rotation or with the arm in ﬂexion
has been documented in cadaver , MRI , and
clinical studies involving arthroscopy [18, 30, 35].
One arthroscopic study suggested rotator cuff contact
with the superior glenoid when the arm was in ﬂexion (as
with a Neer impingement sign) was common, regardless of
the shoulder diagnosis . In that study, patients with
such contact were compared with a control group without
such contact. The factors associated with cuff-glenoid
contact with the arm in ﬂexion were the presence of Type II
superior labrum anterior and posterior lesions and of
osteoarthritis of the humeral head. Although cuff-glenoid
contact was common, that study did not determine the
relationship of cuff-glenoid contact to the position of the
arm at which pain occurred. However, cuff-glenoid contact
seemed to occur at a degree of arm elevation similar to that
described by Neer for a positive sign.
Therefore, we asked whether in patients with a positive
Neer impingement sign observed during ofﬁce examina-
tion, the degree of ﬂexion at which the sign became
positive in the clinic would be similar to the arm position in
which the rotator cuff was arthroscopically seen to make
contact with the superior glenoid.
Patients and Methods
From August 1992 through November 2007, any patient
undergoing shoulder surgery for any reason at our institu-
tion was prospectively entered into a database. We
retrospectively reviewed that database and found, of the
total of 1854 patients it had recorded, 1331 had undergone
diagnostic arthroscopy with or without a subsequent open
procedure; 681 of the 1331 patients had a positive Neer
sign preoperatively. Of the 681 patients, we excluded 283:
263 because, during arthroscopy, observation of the cuff-
glenoid contact was obscured by synovitis or was absent
secondary to a large massive rotator cuff tear; and 20 with a
diagnosis of frozen shoulders because the contact under
anesthesia was evaluated after the manipulation. The
remaining 398 patients (191 males, 207 females) had an
average age of 44.2 years (range, 13–86 years). This study
was approved by our Institutional Review Board.
All 398 patients underwent a thorough preoperative
history, completed subjective questionnaires within
4 weeks before surgery, and had a comprehensive physical
examination performed by the senior author (EGM) or
under his supervision. This examination included 646 data
points for motion, strength testing, and provocative
maneuvers, as previously reported [6, 12–14, 19–21, 25,
26, 31, 32].
The Neer sign was performed in the ofﬁce with the
patient standing. Using the technique described by Neer
, the examiner stabilized the affected arm by placing
one hand on the shoulder to limit scapular rotation and used
the second hand to elevate the patient’s arm passively in
ﬂexion with the arm in internal rotation until the patient felt
pain in the anterior or lateral deltoid only. If the patient had
pain elsewhere, it was not considered a positive Neer sign.
For the sign to be positive, the pain had to be in the anterior
or lateral portion of the shoulder near the acromion or in
the deltoid region. The sign was considered negative if
there was pain in the acromioclavicular joint, trapezius
muscle, posterior shoulder joint line, or shoulder blade
region. Once pain in the anterior or lateral deltoid was
reported, the examiner stabilized the patient’s arm in that
position, and a handheld goniometer then was used to
determine the degree of arm ﬂexion (Fig. 1).
All patients subsequently underwent arthroscopy of the
shoulder under general anesthesia with or without a scalene
block. After the induction of anesthesia, the patient was
Fig. 1 A goniometer is held by the examiner to determine the
degrees of arm ﬂexion where pain occurred.
814 Jia et al. Clinical Orthopaedics and Related Research
placed in a lateral decubitus position with a bean bag and
was secured with towels and tape to prevent thorax motion.
The arm was held in a commercially available arm holder
with 10 pounds of traction. The arthroscope was placed in a
standard posterior portal, and the joint was insufﬂated with
saline via a pressurized pump set at 80 mm Hg. The senior
author performed a thorough diagnostic evaluation of the
glenohumeral joint, including inspection for rotator cuff
and labrum abnormalities. Rotator cuff tears of the supra-
spinatus were stratiﬁed by severity by noting whether they
were partial or full thickness . The rotator cuff tears
were not de
brided until the site had been inspected for cuff-
The patient’s arm then was removed from the arm
holder, and an operative assistant on the opposite side of
the surgeon moved the arm into ﬂexion as for a Neer sign
. An assistant held the scapula with one hand, a tech-
nique similar to that used in the ofﬁce examination and as
described by Neer . With the arthroscope held at the
posterior joint line as described previously , the arm
was gradually ﬂexed until cuff-glenoid contact (between
the rotator cuff and the superior labrum anterior to the
biceps attachment) was noted. With the arm held in this
position, the degree of elevation of the shoulder was
measured with a handheld goniometer. This position was
measured to the nearest 5° and represented the degrees at
which the rotator cuff tendon ﬁrst made contact with the
superior glenoid. Next, maximum arm ﬂexion was mea-
sured with the goniometer as the assistant fully elevated the
arm in ﬂexion .
The ﬁnal diagnosis for all patients was determined by
history, physical examination, and arthroscopic ﬁndings.
Radiographic studies were not used as the source of the
ﬁnal diagnosis in this study because all patients had
undergone diagnostic arthroscopy.
We used a paired-samples Student’s t test to compare
the degrees of ﬂexion noted during the preoperative
positive Neer sign with those obtained during shoulder
arthroscopy. A two-tailed Pearson correlation was used to
test correlation between the degrees of ﬂexion noted during
the preoperative positive Neer sign and those obtained
during shoulder arthroscopy. We used a standard statistical
16.0; SPSS, Inc, Chicago, IL, USA) for
Of the 398 patients who had pain with a Neer sign during
ofﬁce examination, 302 (76%) had arthroscopically docu-
mented cuff-glenoid contact. In the 302 patients, the
preoperative measurement of ﬂexion at which the patient
reported pain was similar (p = 0.780) to the intraoperative
measurement of ﬂexion at the point of contact with the
rotator cuff: 120.1° ± 26.7° (95% conﬁdence interval,
117.1°–123.3°) versus 120.6° ± 14.7° (95% conﬁdence
interval, 118.9°–122.3°); we observed a correlation
(r = 0.850; p = 0.011) between the two measures. For the
302 patients, there were no differences in degrees of ﬂexion
at the point of contact according to diagnosis, except for
patients with a diagnosis of isolated acromioclavicular
arthritis (Table 1).
Of the 302 patients, 164 (76%) had rotator cuff disease
(Table 1). For the 164, there was no difference between the
average preoperative and intraoperative degrees of ﬂexion
(121.4° ± 25.5° and 118.8° ± 14.9°, respectively). When
rotator cuff disease was stratiﬁed by severity, only the
patients with partial tears (n = 67) had a difference
between the preoperative and intraoperative degrees of
ﬂexion (p = 0.008) (Table 2).
This study sought to determine if there was a relationship
between the degrees of ﬂexion where a Neer impingement
Table 1. Degrees of preoperative and intraoperative ﬂexion in 302 patients
Primary diagnosis Number of
p Value Difference between
preoperative angles (°)*
Rotator cuff disease
164/216 (75.9%) 121.2 ± 25.5 119.0 ± 14.9 0.360 2.2 ± 0.3 0.360
Biceps and superior labrum
anterior posterior lesion
15/18 (83.3%) 121.7 ± 28.1 117.7 ± 17.0 0.673 4.0 ± 0.4 0.673
Instability 66/93 (71.0%) 124.9 ± 20.0 123.5 ± 14.1 0.650 1.4 ± 0.2 0.650
Acromioclavicular disease 52/62 (83.9%) 110.4 ± 34.2 122.3 ± 13.5 0.025 11.9 ± 0.4 0.025
5/11 (45.5%) 119.0 ± 32.5 124.0 ± 19.5 0.763 5.0 ± 0.3 0.763
Total 302/398 (75.9%) 120.1 ± 26.7 120.6 ± 14.7 0.780 0.5 ± 0.3 0.780
* Values are expressed as mean ± SD;
includes impingement syndrome, partial tears, and full tears;
other diagnoses include osteoarthritis,
osteonecrosis, and soft tissue tumor.
Volume 469, Number 3, March 2011 Rotator Cuff Contact and Neer Impingement 815
sign caused pain during clinic examination and the degrees
of ﬂexion found during arthroscopy of the shoulder where
the rotator cuff contacts the superior glenoid when the arm
is placed in ﬂexion. We found that these two values were
not statistically different and that they were highly corre-
lated. This ﬁnding suggests that the pain of a Neer
impingement sign as performed in the ofﬁce may reﬂect
contact of the rotator cuff to the superior glenoid and not to
the acromion as previously suggested by Neer .
There are several limitations of this study which should
be considered when evaluating the results. First, we used a
ﬂuid pump at the time of arthroscopy that might have
distorted the degrees at which the tendon contacted the
bone. The insufﬂations of the joint may have made the
rotator cuff contact the superior glenoid at a higher angle
than would occur physiologically when there is little ﬂuid
in the joint. However, a ﬂuid pump has been used at the
time of arthroscopy by others evaluating contact of the
rotator cuff with the superior glenoid [7, 15, 17, 18, 24, 35,
37]. Second, it is possible making the measurements with
the patients standing when awake and in the lateral position
under anesthesia could have affected the results. However,
in the ofﬁce and the operating room, the Neer sign was
performed in exactly the same manner and as described by
Neer . In both situations, the arm was raised in forward
elevation in the sagittal plane of the shoulder with the hand
face down, as described by Neer . Third, the limitations
of goniometric measurements using handheld goniometers
are well documented [4, 5, 11, 23, 34, 39]. Interexaminer
reliability is lower than intraexaminer reliability in most
studies in awake subjects [4, 10, 11, 23, 34]. Although in
our study, the only examiner making the measures in the
operating room was the senior author, we did not perform
intraobserver reliability studies to measure arm ﬂexion in
the ofﬁce or in the operating room. Similarly, it is possible
that more sophisticated techniques for measuring shoulder
motion, such as triplanar radiography or electromagnetic
sensors, might provide more accurate data, but none of
these techniques is suited for use in the operating room.
Fourth, we excluded from analysis patients with large to
massive rotator cuff tears because those patients had no
rotator cuff tendons available to make contact with the
superior glenoid and because we consistently observed no
contact of the greater tuberosity with the superior glenoid.
As stated previously, it was not the goal of our study to
determine why patients with massive rotator cuff tears did
or did not have pain. Fifth, we did not attempt to answer
the enigma of why some patients with rotator cuff disease
have or do not have pain with a Neer impingement sign
(the exact cause of rotator cuff irritation has not been fully
elucidated) or to explain why some patients with other
disease entities around the shoulder may experience a
positive Neer impingement sign. Although this study was
designed to correlate arm position with cuff-glenoid con-
tact, it does not suggest this contact is the only source of
pain with a Neer impingement sign. We did not study the
subacromial space as part of this study because some of the
patients did not warrant subacromial inspection; all of the
patients with rotator cuff disease as a primary diagnosis did
have the subacromial space examined openly or arthro-
scopically. Despite the anecdotal suggestion of some
surgeons, we have found it is technically impossible to
view the acromion and coracoacromial ligament arthro-
scopically with the arthroscope in the subacromial space
while moving the arm in ﬂexion. As a result, we did not
explore the possibility that the rotator cuff tendons on the
bursal surface might be contacting other structures. Finally,
we did not perform differential injections in this protean
group of patients to determine other potential sites of pain
in the shoulder.
Our data suggest that the degree of ﬂexion at which
there is pain with the Neer impingement sign on ofﬁce
examination correlates well with the degrees of ﬂexion
where the rotator cuff makes contact with the superior
glenoid arthroscopically. These ﬁndings suggest, but do not
prove, this contact between the rotator cuff and the superior
glenoid may be a pain generator when the arm is ﬂexed in a
manner similar to that of a Neer impingement sign.
Cadaveric studies support our observation that, with arm
ﬂexion greater than 90°
, the rotator cuff makes contact with
the superior glenoid and not the acromion . Graichen
et al. , using MRI of the glenohumeral joint in different
degrees of elevation, measured the closest distance
between the acromion and the greater tuberosity in the
Table 2. Degrees of preoperative and intraoperative ﬂexion in 164 patients
Rotator cuff abnormality Number of patients with contact Preoperative ﬂexion (°)* Intraoperative ﬂexion (°)* p Value
Tendinitis 54/70 (77.1%) 119.5 ± 24.7 121.2 ± 15.1 0.442
Partial tear 51/67 (76.1%) 124.8 ± 23.5 114.7 ± 12.2 0.008
Full tear 59/79 (74.7%) 119.8 ± 27.9 120.3 ± 16.2 0.873
Total 164/216 (75.9%) 121.4 ± 25.5 118.8 ± 14.9 0.360
* Values are expressed as mean ± SD.
816 Jia et al. Clinical Orthopaedics and Related Research
shoulder of 12 healthy volunteers. They found, at 90° of
arm elevation, the closest distance was lateral to the
supraspinatus tendon in 50% of the subjects, and with the
arm abducted 120°, the minimal distance was lateral to
the supraspinatus insertion on the greater tuberosity in all
The exact cause of pain with rotator cuff abnormalities
continues to be unknown, but it has been postulated to be
intrinsic tendon disease , tension overload [1, 2], vas-
cular insufﬁciency , and impingement of the rotator
cuff to the acromion, the coracoacromial ligament, the
coracoid, or the posterior-superior glenoid. We did not
conﬁrm nor refute any of these mechanisms as the cause of
pain in our patients, but we did establish by arthroscopic
visual examination with the arm in ﬂexion (as for a Neer
impingement sign), the rotator cuff was in contact with the
superior glenoid at the same angle that the Neer impinge-
ment sign produces symptoms during examination in the
ofﬁce. This ﬁnding suggests, in some patients, the pain
produced with a positive Neer impingement sign may not
be generated from contact between the rotator cuff and the
acromion, as originally suggested by Neer . It is pos-
sible the pain pattern attributed to rotator cuff disease is
multifactorial or the result of causes other than contact
between the rotator cuff and the anterolateral acromion.
Additional study is needed to delineate the role of cuff-
glenoid contact in patients with symptomatic rotator cuff
disease and to determine why not all patients have pain.
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