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Background: No study has previously investigated the side, duration or number of audible cavitation sounds during high-velocity low-amplitude (HVLA) thrust manipulation to the cervicothoracic spine. Purpose: The primary purpose was to determine which side of the spine cavitates during cervicothoracic junction (CTJ) HVLA thrust manipulation. Secondary aims were to calculate the average number of cavitations, the duration of cervicothoracic thrust manipulation, and the duration of a single cavitation. Study design: Quasi-experimental study. Methods: Thirty-two patients with upper trapezius myalgia received two cervicothoracic HVLA thrust manipulations targeting the right and left T1-2 articulation, respectively. Two high sampling rate accelerometers were secured bilaterally 25 mm lateral to midline of the T1-2 interspace. For each manipulation, two audio signals were extracted using Short-Time Fourier Transformation (STFT) and singularly processed via spectrogram calculation in order to evaluate the frequency content and number of instantaneous energy bursts of both signals over time for each side of the CTJ. Result: Unilateral cavitation sounds were detected in 53 (91.4%) of 58 cervicothoracic HVLA thrust manipulations and bilateral cavitation sounds were detected in just five (8.6%) of the 58 thrust manipulations; that is, cavitation was significantly (p<0.001) more likely to occur unilaterally than bilaterally. In addition, cavitation was significantly (p<0.0001) more likely to occur on the side contralateral to the clinician's short-lever applicator. The mean number of audible cavitations per manipulation was 4.35 (95% CI 2.88, 5.76). The mean duration of a single manipulation was 60.77 ms (95% CI 28.25, 97.42) and the mean duration of a single audible cavitation was 4.13 ms (95% CI 0.82, 7.46). In addition to single-peak and multi-peak energy bursts, spectrogram analysis also demonstrated high frequency sounds, low frequency sounds, and sounds of multiple frequencies for all 58 manipulations. Discussion: Cavitation was significantly more likely to occur unilaterally, and on the side contralateral to the short-lever applicator contact, during cervicothoracic HVLA thrust manipulation. Clinicians should expect multiple cavitation sounds when performing HVLA thrust manipulation to the CTJ. Due to the presence of multi-peak energy bursts and sounds of multiple frequencies, the cavitation hypothesis (i.e. intra-articular gas bubble collapse) alone appears unable to explain all of the audible sounds during HVLA thrust manipulation, and the possibility remains that several phenomena may be occurring simultaneously. Level of evidence: 2b.
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The International Journal of Sports Physical Therapy | Volume 12, Number 4 | August 2017 | Page 642
ABSTRACT
Background: No study has previously investigated the side, duration or number of audible cavitation sounds during high-velocity low-amplitude
(HVLA) thrust manipulation to the cervicothoracic spine.
Purpose: The primary purpose was to determine which side of the spine cavitates during cervicothoracic junction (CTJ) HVLA thrust manipula-
tion. Secondary aims were to calculate the average number of cavitations, the duration of cervicothoracic thrust manipulation, and the duration of
a single cavitation.
Study Design: Quasi-experimental study
Methods: Thirty-two patients with upper trapezius myalgia received two cervicothoracic HVLA thrust manipulations targeting the right and left
T1-2 articulation, respectively. Two high sampling rate accelerometers were secured bilaterally 25 mm lateral to midline of the T1-2 interspace. For
each manipulation, two audio signals were extracted using Short-Time Fourier Transformation (STFT) and singularly processed via spectrogram
calculation in order to evaluate the frequency content and number of instantaneous energy bursts of both signals over time for each side of the CTJ.
Result: Unilateral cavitation sounds were detected in 53 (91.4%) of 58 cervicothoracic HVLA thrust manipulations and bilateral cavitation sounds
were detected in just five (8.6%) of the 58 thrust manipulations; that is, cavitation was significantly (p<0.001) more likely to occur unilaterally than
bilaterally. In addition, cavitation was significantly (p<0.0001) more likely to occur on the side contralateral to the clinician’s short-lever applicator.
The mean number of audible cavitations per manipulation was 4.35 (95% CI 2.88, 5.76). The mean duration of a single manipulation was 60.77 ms
(95% CI 28.25, 97.42) and the mean duration of a single audible cavitation was 4.13 ms (95% CI 0.82, 7.46). In addition to single-peak and multi-
peak energy bursts, spectrogram analysis also demonstrated high frequency sounds, low frequency sounds, and sounds of multiple frequencies for
all 58 manipulations.
Discussion: Cavitation was significantly more likely to occur unilaterally, and on the side contralateral to the short-lever applicator contact, during
cervicothoracic HVLA thrust manipulation. Clinicians should expect multiple cavitation sounds when performing HVLA thrust manipulation to
the CTJ. Due to the presence of multi-peak energy bursts and sounds of multiple frequencies, the cavitation hypothesis (i.e. intra-articular gas
bubble collapse) alone appears unable to explain all of the audible sounds during HVLA thrust manipulation, and the possibility remains that
several phenomena may be occurring simultaneously.
Level of Evidence: 2b
Key words: Cavitation, cervicothoracic spine, spinal manipulation, thrust
IJSPT
ORIGINAL RESEARCH
CAVITATION SOUNDS DURING CERVICOTHORACIC
SPINAL MANIPULATION
James Dunning, DPT, MSc, FAAOMPT1,2
Firas Mourad, PT, OMPT, Dip. Osteopractic1,2
Andrea Zingoni, MSc3
Raffaele Iorio, PT, Cert. DN4
Thomas Perreault, DPT, OCS, Dip. Osteopractic2
Noah Zacharko, DPT, FAAOMPT, Dip. Osteopractic2,5
César Fernández de las Peñas, PhD, DO, PT6
Raymond Butts, PhD, DPT, MSc2,7
Joshua A. Cleland, PhD, DPT, FAAOMPT8
1 PhD student, Escuela Internacional de Doctorado,
Universidad Rey Juan Carlos, Alcorcón, Madrid, Spain
2 American Academy of Manipulative Therapy Fellowship in
Orthopaedic Manual Physical Therapy, Montgomery, AL, USA
3 Università di Pisa, Information Engineering Department,
Pisa, Italy
4 Koinè Physiotherapy, Florence, Italy
5 Osteopractic Physical Therapy of the Carolinas, Charlotte,
NC, USA
6 Department of Physical Therapy, Occupational Therapy,
Rehabilitation and Physical Medicine, Universidad Rey Juan
Carlos, Alcorcón, Madrid, Spain
7 Research Physical Therapy Specialists, Columbia, SC, USA
8 Franklin Pierce University, Manchester, NH, USA
Acknowledgements
None of the authors received any funding for this study. The
authors wish to thank all the participants of the study.
Declaration of Interests
The authors report no declarations of interest.
CORRESPONDING AUTHOR
Dr. James Dunning
1036 Old Breckenridge Lane
Montgomery, AL 36117
E–mail: jamesdunning@hotmail.com
The International Journal of Sports Physical Therapy | Volume 12, Number 4 | August 2017 | Page 643
INTRODUCTION
Reductions in pain and disability following high-
velocity low-amplitude (HVLA) thrust manipula-
tion to the cervicothoracic region have been widely
reported in patients with neck pain1-11 and shoulder
pain.12-16 However, the frequency, location, and etiol-
ogy of the cracking, popping or clicking noises that
often accompany HVLA thrust manipulative proce-
dures to the spine17-25 are still poorly understood.23,26-30
Four previous studies31-34 have suggested that the
“audible popping” following HVLA thrust manipula-
tion is not related to the clinical outcomes of pain
and/or disability. Nevertheless, many clinicians19,22,35
and researchers20,21,36-42 still appear to repeat the
HVLA thrust manipulation if they do not hear or pal-
pate popping sounds. Moreover, Evans and Lucas27
proposed the “audible popping”, or the “mechanical
response” that “occurs within the recipient”, should
be present to satisfy the criteria for a valid manipula-
tion.27 However, it remains to be elucidated whether
HVLA thrust manipulation to the cervicothoracic
spine should normally be accompanied by single,
multiple or no cavitation sounds. Furthermore,
understanding whether the cavitation phenomenon
during cervicothoracic HVLA thrust manipulation
is an ipsilateral, contralateral or bilateral event may
help inform clinicians in selecting the appropriate
manipulation technique that will most effectively
target the dysfunctional articulation with the ulti-
mate goal of reducing pain and disability.
The traditional expectation of a single pop or cavita-
tion sound emanating from the target or dysfunctional
facet joint during HVLA thrust manipulation43,44 is
not consistent with the existing literature for the
upper cervical,26 lower cervical,24,45 thoracic25 or lum-
bar17,20,25 regions. Moreover, the evidence suggests
that HVLA thrust manipulation directed at the spine
creates multiple cavitation sounds.17,24-26,45 Neverthe-
less, the question of whether these multiple cavita-
tion sounds emanate from the same joint, adjacent
ipsilateral or contralateral joints, or even extra-artic-
ular soft-tissues remains to be elucidated.17,18,20,25,26,46
To date, only three studies18,24,26 have investigated
the side of joint cavitation during cervical spine
manipulation. During “lateral to medial and rota-
tory” HVLA thrust manipulations targeting the C3-4
facet joint, Reggars and Pollard24 found 47 (94%) of
50 subjects exhibited “cracking sounds” on the con-
tralateral side to the applicator contact, while two
subjects exhibited bilateral sounds and one subject
an ipsilateral sound. Additionally, following C3-4
thrust manipulations in 20 asymptomatic subjects,
Bolton et al18 reported cavitation sounds were signif-
icantly more likely to occur on the contralateral side
to the applicator for “rotation” manipulations, but
equally likely to occur on either side during “side-
bending” manipulations. Nevertheless, Bolton et al18
made the assumption that the side with the larger
amplitude sound wave was the side of “initial cavita-
tion” and hence did not report if single or multiple
cavitations occurred. That is, unless single cavitation
events occurred during all cervical manipulations,
which is unlikely given the findings of previous
studies,17,20,24,25,45 the possibility remains that the “ini-
tial cavitation” occurred on one side, and additional
cavitations that were not counted also occurred ipsi-
laterally and/or contralaterally. Most recently, Dun-
ning et al26 reported bilateral cavitation sounds in 34
(91.9%) of 37 manipulations, while unilateral cavita-
tion sounds were detected in just 3 (8.1%) manipula-
tions following HVLA thrust manipulation targeting
the upper cervical spine (C1-2) articulation. How-
ever, it is unknown if the same findings would occur
in a different spinal region—i.e. the cervicothoracic
junction (CTJ)—and whether using a different HVLA
thrust technique with the patient in prone, that is
traditionally considered a “lateral break” manipula-
tion35,47-49 (due to the simultaneous delivery of lateral
flexion and lateral translation forces as opposed to
primarily employing rotatory forces for the thrust-
ing impulse35,50), would alter the side of cavitation
and therefore the location of the target articulation
that will most likely be effected by the high-velocity
thrusting forces.17,18,20,24,26,28
Gas bubble collapse,51 or the cavitation phenomenon,
has been traditionally accepted as the mechanism for
creating the joint cracking sound.18,23,27,30,45,51-53 How-
ever, a recent study by Kawchuk et al29 challenged
the cavitation hypothesis, and proposed that joint
cracking is associated with cavity formation within
synovial fluid rather than cavity collapse. Neverthe-
less, although this first in-vivo macroscopic demon-
stration of tribonucleation was recorded using rapid
cine magnetic resonance images on 10 MCP joints, it
was from a single subject.29 Furthermore, the notion
The International Journal of Sports Physical Therapy | Volume 12, Number 4 | August 2017 | Page 644
that the audible popping sounds were coming from
cavity inception, rather than collapse of a pre-exist-
ing bubble, is not new and was first proposed by Ros-
ton and Haines as early as 1947.54 However, neither
of these two studies29,54 can be generalized to zyg-
apophyseal joints.
Identifying normative values for the duration of
HVLA thrust procedures23,26,55,56 for different spinal
regions may help facilitate a better understanding of
the physical parameters surrounding spinal manipu-
lation28,50,55 (e.g. velocity, acceleration) and the spe-
cific psychomotor skills required by practitioners to
efficiently perform spinal thrust manipulations.28,48
Additionally, it still remains to be elucidated whether
the popping sounds during HVLA thrust manipula-
tion originate from intra-articular gas bubble col-
lapse, cavity inception within synovial fluid, or
extra-articular events.26,29,30,46,51 Therefore, identify-
ing the duration of individual cavitation sounds,23,24,26
analyzing the instantaneous energy bursts and fre-
quency content of the sound waves23,26,45 produced
during thrust manipulations may help uncover the
etiology29,46,52,53,57—i.e. what structures, tissues, or
mechanisms are involved—and therefore the rela-
tive importance of the audible sounds during thrust
manipulations.27,31,32,34
For cervical manipulations, the duration of the
thrusting procedure has been reported to be 80-200
ms.23,26,50,55,56 Additionally, using 95% of the instan-
taneous energy burst—i.e. the amount of energy
released in a given sampling interval of the spectro-
gram—to calculate the duration of single cavitation
sounds during upper cervical HVLA thrust manip-
ulation, Dunning et al26 reported a mean duration
of 5.66 ms. However, no study has previously mea-
sured the duration of the thrusting procedure or the
duration of single cavitation sounds, during HVLA
thrust manipulation to the CTJ.
To the best of the authors’ knowledge, no study has
investigated the side, duration or number of audible
cavitation sounds during HVLA thrust manipula-
tion to the cervicothoracic spine. Therefore, the pri-
mary purpose of the study was to determine which
side of the spine cavitates during cervicothoracic
HVLA thrust manipulation. Secondary aims of the
study were to calculate the duration of a single cer-
vicothoracic thrust manipulation procedure, and the
average number of cavitation sounds following cer-
vicothoracic HVLA thrust manipulation.
METHODS
Participants
Thirty-two individuals with upper trapezius myalgia,
i.e. a painful upper trapezius muscle, (20 females
and 12 males) were recruited by convenience sam-
pling from a private physical therapy outpatient
clinic in Florence, Italy during November of 2013.
Their ages ranged between 23 and 65 years with a
mean (SD) of 39 (11) years. Height ranged between
152 and 182 cm with a mean (SD) of 170.1 (8.5) cm.
Weight was 50.0 kg to 96.0 kg with a mean (SD) of
67.7 (12.6) kg. All subjects reported being physically
active, to include walking, running, cycling or regu-
lar sports participation.
For subjects to be eligible, they had to present with
neck pain for greater than three months, have a pri-
mary complaint of a painful spot (i.e., active trig-
ger point) in the upper trapezius muscle, and be
between 18 and 65 years of age. The ethics com-
mittee at the Universidad Rey Juan Carlos, Madrid,
Spain, approved this study. All subjects provided
written informed consent before their participation
in the study.
Patients were excluded if they exhibited: 1) any red
flags (i.e., tumor, fracture, metabolic diseases, rheu-
matoid arthritis, osteoporosis, resting blood pres-
sure greater than 140/90 mmHg, prolonged history
of steroid use, etc.); 2) presented with 2 or more
positive neurologic signs consistent with nerve root
compression (muscle weakness involving a major
muscle group of the upper extremity, diminished
upper extremity deep tendon reflex, or diminished
or absent sensation to pinprick in any upper extrem-
ity dermatome); 3) presented with a diagnosis of
cervical spinal stenosis; 4) exhibited bilateral upper
extremity symptoms; 5) had evidence of central
nervous system disease (hyperreflexia, sensory dis-
turbances in the hand, intrinsic muscle wasting of
the hands, unsteadiness during walking, nystagmus,
loss of visual acuity, impaired sensation of the face,
altered taste, the presence of pathological reflexes);
6) had a history of whiplash injury within the pre-
vious three months; or, 7) had prior surgery to the
neck or thoracic spine. Of the 33 patients that were
The International Journal of Sports Physical Therapy | Volume 12, Number 4 | August 2017 | Page 645
thumb of the right hand contact the superomedial
aspect of the patient’s right shoulder girdle. The
long or upper lever was manufactured by having the
therapist place the heel and palm of his left hand
over the temporal region of the patient’s lateral cra-
nium. To localize the forces to the left T1-2 articula-
tion, secondary levers of extension, lateral flexion,
translation and minimal rotation were used. While
maintaining the secondary levers, the therapist per-
formed a single HVLA thrust manipulation using
the simultaneous delivery of the thrusting primary
levers of lateral flexion from the upper lever and lat-
eral translation from the lower lever, i.e., a lateral
break. This was repeated using the same procedure
but directed to the right T1-2 articulation. Prior to
data collection, an independent researcher made
random allocation cards using a computer-gener-
ated table of randomly assigned numbers;60 these
cards were then used to determine the target side
and delivery order of the T1-2 HVLA thrust manipu-
lations for all subjects. Cavitation sounds—i.e. pop-
ping or cracking noises—were heard on all HVLA
thrust manipulations; hence, there was no need for
second attempts.
invited to enter the study, none refused participa-
tion; however, one subject was excluded due to a his-
tory of a previous whiplash injury.
Notably, pain or disability scores were not collected
in any subjects for two reasons: (1) the primary pur-
pose of this study was to investigate the frequency,
location and possible etiologies of the cavitation
phenomenon during cervicothoracic HVLA thrust
manipulation at a single point in time (i.e. no fol-
low-up period), not to measure changes in pain or
disability over time in response to a single manipu-
lation technique given on just one occasion, and (2)
all subjects were current patients at a physiotherapy
practice in Florence, Italy, and as such, were already
receiving conventional physiotherapy treatments for
their primary complaint of upper trapezius myalgia.
Moreover, significant reductions in pain and disabil-
ity scores following HVLA thrust manipulation to
the cervicothoracic region have already been widely
investigated and reported in patients with neck
pain1-11 and shoulder pain.12-16 However, although
cracking, popping or clicking noises often accom-
pany HVLA thrust manipulative procedures,17-25 the
frequency, location and etiology of the cavitation
phenomenon itself is still poorly understood.23,26-30
Manipulative Physiotherapist
A single, U.S. licensed physical therapist performed
all of the cervicothoracic HVLA thrust manipula-
tions in the current study. At the time of data col-
lection, the physical therapist had completed a
post-graduate Master of Science in Advanced Manip-
ulative Therapy, had worked in clinical practice for
14 years, and routinely used cervicothoracic HVLA
thrust manipulation in daily practice.
Cervicothoracic Junction (CTJ) HVLA
Thrust Manipulation Technique
A single “lateral break” HVLA thrust manipula-
tion directed to the CTJ with the patient prone
was performed (Figure 1). T1-2 was the target level
because this segment is in the center of the three
articulations (i.e. C7-T1, T1-T2, T2-3) that are con-
sidered to be primarily affected by the manual
forces during prone HVLA thrust manipulations to
the CTJ.12,22,28,47,50,58,59 For this technique,47 the short
or lower lever was produced by having the thera-
pist’s proximal phalanx, metacarpal, web space and
Figure 1. High-velocity low-amplitude thrust manipulation
directed to the articulation of the left cervicothoracic (T1-2)
junction.
The International Journal of Sports Physical Therapy | Volume 12, Number 4 | August 2017 | Page 646
for each thrust manipulation.26 A spectrogram is a
two-dimensional representation of a signal with time
on the x-axis, frequency on the y-axis, and color as a
third dimension to express the amplitude, or power
of the sound (Figure 3). For each two-channel audio
recording, the spectrograms were computed using
STFT in order to evaluate the frequency content of
both signals over time. The epoch length was set to
0.78 ms (i.e. 75 times the sampling rate) with a 0.1%
overlap between adjacent epochs, resulting in a fre-
quency resolution of 94 Hz. The frequency scale was
set between 10 Hz and 23 kHz, since this is the audi-
ble spectrum for a human being (including a small
margin of error).61
Data Processing
The sound in every audio track was processed as a
digital signal with the amplitude varying discretely
as a function of time. Each channel was depicted by
a separate graph, representing the two recordings
of the left and right accelerometers during a single
HVLA thrust manipulation to the CTJ. Although the
recordings were collected and processed singularly
for each person and for each manipulation, we did
jointly inspect and analyze the left and right chan-
nels for each HVLA thrust manipulation in order to
determine whether the cavitation phenomenon was
a bilateral, ipsilateral or contralateral event, and in
order to accurately sum the total number of cavita-
tions (i.e. pops) during a single manipulation.
In order to isolate the time interval in which the
manipulation took place, the audio tracks of the
left and right channels (relative to a single manip-
ulation) were first listened to using a stereophonic
system. The peculiar sound emitted, together with
visual inspection of the right and left graphs of the
digital audio signal, allowed for easy recognition of
such an interval. The correct time interval featur-
ing the manipulation event was then confirmed
and adjusted by decelerating the audio speed by a
factor of 0.01 and listening to the track again. This
allowed us to identify the beginning and the end
of the manipulations (based on sound, not angular
movements of the spine), and also to identify how
many cavitations (i.e. pops) were present. More spe-
cifically, this operation permitted us to increase the
resolution of the human ear by 100 fold, allowing us
to discriminate and sum the total number of cavita-
Accelerometer Placement and Sound Collection
Prior to the delivery of cervicothoracic HVLA thrust
manipulation, skin mounted accelerometers were
secured bilaterally 25 mm lateral to the midline of the
T1-T2 interspace (Figure 2). The microphones were
connected to a data acquisition system (FOCUSRITE,
High Wycombe, Buckinghamshire, U.K., Scarlett 2i2, 96
KHz, 24-bit conversion) and a MacBook Pro laptop with
AUDACITY software (Open Source Software, Carnegie
Mellon University, Pennsylvania, U.S.A.) for audio
acquisition.26 Sampling frequency was set at 96,000 Hz
and the amplitude was normalized by AUDACITY soft-
ware to values ranging between -1 and +1 (no unit of
measurement). With the order of delivery randomized
(i.e. right side versus left side), all subjects then received
two HVLA thrust manipulations: one targeting the left
(T1-2) CTJ, and one targeting the right (T1-2) CTJ. The
sound wave signals and resultant cavitation sounds
during the cervicothoracic HVLA thrust manipulations
were recorded by an individual not involved in data
extraction or analysis. Data extraction and processing
occurred later and were performed by an individual
blinded to target side. Although target side and deliv-
ery order were randomly assigned using a computer-
generated table of randomly assigned numbers, it was
not possible to fully blind the third researcher who
performed data analysis because knowledge of target
side was required to complete some of the statistical
tests—for example, whether cavitation was more likely
to occur on the side ipsilateral or contralateral to the
clinician’s short-lever applicator.
Data Extraction
Short-Time Fourier Transformation (STFT) was used
to process the sound signals and obtain spectrograms
Figure 2. Bilateral placement and securing of skin-mounted
accelerometers 25 mm lateral to the midline of the T1-2 inter-
space.
The International Journal of Sports Physical Therapy | Volume 12, Number 4 | August 2017 | Page 647
tions. Moreover, listening of the audio tracks with a
100-fold deceleration factor and visual inspection of
the spectrograms for peaks were both used to deter-
mine the number of cavitations present.
The spectrograms show the “location” of the energy
of the audio signals over time and over frequency
jointly. In figure 3, the spectrograms for the right and
left channels for a single HVLA thrust manipulation
are depicted, with time on the x-axis, frequency on the
y-axis and energy on the z-axis (using a map of colors).
Process for Counting the Number of
Cavitations
Per the protocol previously described,26 the graphs
representing the amount of released energy over
time in both the left and right accelerometry chan-
nels were visually inspected in order to identify
instantaneous energy bursts corresponding to cavi-
tations (Figure 4). The total number of cavitations
per manipulation was the sum of the number of
energy bursts identified.
Process for Determining the Side of
Cavitation
For each of the 252 pops generated during 58 cervi-
cothoracic HVLA thrust manipulations, the side of
cavitation was determined by inspecting each of the
energy bursts for the right and left spectrograms.26
Since graphs were computed and the amount of
energy was quantified at each epoch separately
for the two channels, the side of cavitation could
be immediately determined by looking at which
side the energy burst occurred on. In the event of
Figure 3. Spectrograms for the left and right audio channels during cerviothoracic HVLA thrust manipulation. Vertical energy
peaks represent individual pops.
Figure 4. Amount of energy released over time for the right and left accelerometry channels.
The International Journal of Sports Physical Therapy | Volume 12, Number 4 | August 2017 | Page 648
tation event was considered as the duration of a sin-
gle cavitation (Figure 5).
Process for Calculating the Duration of the
Thrust Manipulation
For each thrust manipulation, the time interval
between the beginning of first cavitation and the end
of the last cavitation was considered as the duration
of the thrusting procedure (Figure 6).26 However,
we did not measure the actual forces against time;
therefore, the duration of the thrust manipulation
likely does not include the time from when the force
beyond the preload first began to be applied, or the
entire interval from when the peak forces dropped
back to zero.28,48,50
simultaneous bursts on both channels, the one that
began earlier and had the higher energy value was
selected; moreover, the smaller and delayed energy
burst represented the echo of the original event. A
similar methodology for determining the side of cav-
itation was previously reported for the upper cervi-
cal spine.26
Process for Calculating the Duration of a
Single Cavitation
For each of the 252 cavitations (i.e. popping sounds)
detected during 58 cervicothoracic HVLA thrust
manipulations, the time interval between the begin-
ning of the ascent of the first energy burst and the
end of the descent of the last energy burst of a cavi-
Figure 5. The time interval used to calculate the duration of a single pop during cervicothoracic HVLA thrust manipulation.
Figure 6. The time interval used to calculate the duration of cervicothoracic HVLA thrust manipulation.
The International Journal of Sports Physical Therapy | Volume 12, Number 4 | August 2017 | Page 649
Unilateral cavitation sounds were detected in 53
(91.4%) of the 58 cervicothoracic lateral break HVLA
thrust manipulations and bilateral cavitation sounds
were detected in just 5 (8.6%) of the 58 thrust manip-
ulations; that is, cavitation was significantly (bino-
mial Test, p<0.001) more likely to occur unilaterally
than bilaterally.
One distinct cavitation sound (i.e. a single popping
noise) was produced in 4 (6.9%) of the manipula-
tions, whereas 2 (3.5%), 12 (20.7%), 10 (17.2%), 15
(25.9%), 13 (22.4%), 1 (1.7%) and 1 (1.7%) manipu-
lations produced 2, 3, 4, 5, 6, 7 and 8 distinct cavi-
tation sounds, respectively. The mean duration of
a single cavitation was 4.13 ms (95%CI: 0.82, 7.46)
and the mean duration of a single CTJ HVLA thrust
manipulation was 60.77 ms (95%CI 28.25, 97.42).
In addition to single-peak and multi-peak energy
bursts, high frequency sounds, low frequency
sounds, and sounds of multiple frequencies for each
of the 58 cervicothoracic HVLA thrust manipula-
tions were also identified via spectrogram analysis
(Figures 3, 5 and 6).
DISCUSSION
Side of the cavitation
The results indicate that cavitation was significantly
more likely to occur on the side contralateral to the
short-lever applicator of the manipulative phys-
iotherapist following right or left cervicothoracic
HVLA thrust manipulation. In addition, unilateral
cavitation sounds were detected in 53 (91.4%) HVLA
thrust manipulations, while bilateral cavitation
sounds were detected in just 5 (8.6%) cases. Result-
ing cavitation sounds were 10.5 times more likely
to occur on the side contralateral to the short-lever
applicator of the manipulative physiotherapist than
the ipsilateral side. Understanding whether the cavi-
tation phenomenon during cervicothoracic HVLA
thrust manipulation is an ipsilateral, contralateral or
bilateral event may help inform clinicians in select-
ing the appropriate thrust manipulation technique
that will most effectively target the dysfunctional
articulation with the ultimate goal of reducing pain
and disability.
Previous authors have investigated the frequency
and location of audible cavitations during cervi-
Data Analysis
Sound waves resulting from the cervicothoracic
HVLA thrust manipulations were displayed in
graphical format. Each subject had one right and one
left graph corresponding with each thrust procedure
(i.e. four graphs in total for each subject). Means and
standard deviations were calculated to summarize
the average number of pops, the duration of cervi-
cothoracic thrust manipulation, and the duration of
a single cavitation. The primary aim, to determine
which side of the spine cavitates during CTJ (T1-
2) HVLA thrust manipulation, was examined using
a Chi-square test. The probability for unilateral or
bilateral cavitation events was calculated using the
binomial test assuming an expected probability of
50% (i.e. a reference proportion of 0.5). Data analy-
sis was performed using SPSS 23.0.
RESULTS
Subjects ranged between 23 and 65 years of age,
with a mean of 39 (SD: 11) years. Of the 252 total
cavitations during 58 HVLA thrust manipulations,
22 occurred ipsilateral and 230 occurred contralat-
eral to the targeted T1-2 articulation; that is, cavita-
tion was significantly more likely to occur on the
side contralateral to the short-lever applicator of the
manipulative physiotherapist (p<0.0001) following
right or left thrust manipulation to the CTJ. More-
over, during T1-2 HVLA thrust manipulation tar-
geting the right or left CTJ, the resulting cavitation
sounds were 10.5 times more likely to occur on the
side contralateral to the short-lever applicator of the
manipulative physiotherapist than the ipsilateral
side.
All 58 cervicothoracic HVLA thrust manipulations
resulted in one or more audible joint cavitation
sounds (range, 1-8). Two hundred fifty-two cavitation
sounds were detected following 58 cervicothoracic
thrust manipulations giving a mean of 4.35 (95%CI
2.88, 5.76) distinct cavitation sounds (i.e. pops or
cracks) per cervicothoracic HVLA thrust manipula-
tion procedure. More specifically and on average,
for each cervicothoracic HVLA thrust manipula-
tion procedure, 3.97 (SD 1.65) of the 4.35 cavitation
sounds (i.e. 91.3%) occurred on the side contralat-
eral to the short-lever applicator of the physiothera-
pist, whereas, 0.38 (SD 0.75) of the 4.35 cavitation
sounds occurred ipsilateral (i.e. 8.7%).
The International Journal of Sports Physical Therapy | Volume 12, Number 4 | August 2017 | Page 650
Number of cavitations per thrust
Following 58 cervicothoracic thrust manipulations,
252 cavitation sounds were identified resulting in
a mean of 4.35 distinct cavitations (i.e. popping or
cracking noises) and a range of one to eight cavita-
tions per T1-2 HVLA thrust manipulation. Similarly,
following 37 upper cervical thrust manipulations,
Dunning et al26 reported a mean of 3.57 (range of
1 to 7) cavitations per C1-2 HVLA thrust manipu-
lation. Likewise, Reggars45 reported 123 individual
“joint cracks” resulting in a mean of 2.46 cavitations
and a range of 1-5 cavitations per C3-4 HVLA thrust
manipulation. Similarly and in agreement with
the current study, Reggars and Pollard24 reported a
mean of 2.32 (range of 1 to 5) cavitations per C3-4
manipulation.
Although bubble collapse, or the cavitation model51
has been widely accepted for the past four decades
as the mechanism of “joint cracking”,18,23,27,30,45,51-53
a recent study by Kawchuk et al29 reported a “dark
intra-articular void” during MCP distraction. Nota-
bly, this “dark intra-articular void” was associated
with concurrent sound production; that is, the “joint
cracking” was associated in time with cavity forma-
tion (rather than cavity collapse) within the synovial
fluid, and with an average of 1.89 mm of joint surface
separation. Kawchuk et al29 referred to this process
as tribonucleation; that is, when sufficient distrac-
tive force overcomes the viscous attraction or adhe-
sive forces between opposing joint surfaces, rapid
separation of the articulation occurs with a resulting
drop in synovial pressure, allowing dissolved gas to
come out of solution to form a bubble, cavity, clear
space or void within the joint.
In this study sounds composed of single energy
bursts (i.e. single audible popping sounds) and also
sounds composed of multiple energy bursts (i.e.
multiple audible popping sounds) were observed.
However, whether the multiple cavitation sounds
found in this study emanated from the same joint,
adjacent ipsilateral or contralateral facet or unco-
vertebral joints, or even extra-articular soft-tissues
remains to be elucidated. In addition to single and
multiple energy releases, high frequency sounds,
low frequency sounds, and sounds of multiple fre-
quencies were also identified in this study. There-
fore, as opposed to the cavitation hypothesis alone
cal18,24,26 and lumbopelvic17,20 HVLA thrust manipu-
lation; however, this study is the first to report the
frequency and side of cavitation during cervicotho-
racic HVLA thrust manipulation. Additionally, in
the current study accelerometers were mounted
directly over the target articulation (i.e. 25 mm
lateral to the midline of the T1-T2 interspace),
whereas both Bolton et al18 and Reggars and Pollard24
mounted microphones over the articular pillar and
transverse process, respectively, of the C2 vertebra
when the target was the C3-4 articulation in each
of those studies. Additionally, Bolton et al18 used a
significantly lower sampling frequency of 2000 Hz
(compared to 96,000 Hz in our study); thus, they
were only able to analyze signal amplitude in the
determination for the side of the cavitation. Further-
more, Bolton et al18 made the assumption that the
side with the larger amplitude sound wave was the
side of “initial cavitation” and hence did not report
if single or multiple cavitations occurred. Unless
single cavitation events occurred during all cervical
manipulations, which is unlikely given the findings
of previous studies,17,20,24,25,45 the possibility remains
that the “initial cavitation” occurred on one side, and
additional cavitations that were not counted also
occurred ipsilaterally and/or contralaterally at adja-
cent segments.
Notably, Ross et al25 found most thoracic and lum-
bar HVLA thrust manipulations produced two to six
audible cavitation sounds with an average error from
the target joint of 3.5 cm and 5.29 cm, respectively.
Additionally, Beffa and Mathews17 reported lumbar
and sacroiliac HVLA thrust manipulations had low
specificity and poor accuracy for the target articula-
tion. Of the 252 total cavitations identified in this
study, 22 (8.7%) occurred ipsilateral and 230 (91.3%)
occurred contralateral; that is, cavitation was signifi-
cantly more likely to occur on the side contralateral
to the short-lever applicator of the manipulative
physiotherapist. Therefore, considering the findings
of previous studies17,20,25 and based on the results of
this study, in order to maximize the likelihood that
the target articulation is indeed manipulated, it may
be appropriate to perform the T1-2 HVLA thrust
manipulation with the practitioner standing on the
target side of the CTJ, i.e., the short lever applica-
tor on the side opposite the target or symptomatic
articulation.
The International Journal of Sports Physical Therapy | Volume 12, Number 4 | August 2017 | Page 651
C2-3 lateral break manipulation; whereas, Ngan et
al55 used a four camera motion analysis system to
measure head on trunk angular movements (and
indirectly thrust duration) during lower cervical
rotational manipulations in eight asymptomatic sub-
jects. Additionally, Herzog et al23 measured thrust
duration using “instantaneous acceleration signals”
from a mechanical accelerometer during T4 poste-
rior to anterior thrust manipulations in 28 subjects
with thoracic pain. Therefore, considering the dif-
ferent instrumentation and analytical methods used
in each of the previous studies,23,26,55,56 there does
not appear to be a consistent reference standard for
measuring thrust duration. Nevertheless, to date,
this study is the first to report the thrust duration
for a manipulation technique that targets the T1-2
articulations.
Clinical relevance of the cavitation sounds
The cavitation sound is traditionally considered
by many physical therapists, chiropractors, and
osteopaths to be an important indicator for the suc-
cessful technical delivery of an HVLA thrust manip-
ulation.19,20,22,23,25,35,39,40,56 However, four previous
studies31-34 have suggested that the “audible pop” fol-
lowing HVLA thrust manipulation is not related to
the clinical outcomes of pain and/or disability. Nev-
ertheless, these authors31-34 investigated the thoracic
and lumbopelvic regions, not the cervical spine or
CTJ. Notably, many clinicians19,22,35 and research-
ers20,21,36-42 still appear to repeat the HVLA thrust
manipulation if they do not hear or palpate popping
sounds. Moreover, Evans and Lucas27 proposed the
“audible popping”, or the “mechanical response” that
“occurs within the recipient”, should be present to
satisfy the criteria for a valid manipulation.27 Under-
standing whether the cavitation phenomenon dur-
ing cervicothoracic HVLA thrust manipulation is an
ipsilateral, contralateral or bilateral event will help
inform practitioners of spinal manipulative therapy
in selecting the appropriate technique that will
most effectively target the dysfunctional articula-
tion with the ultimate goal of reducing pain and dis-
ability. More specifically, considering the findings
of previous studies17,20,25 and based on the results of
our study, in order to maximize the likelihood that
the target articulation is indeed manipulated, the
practitioner should stand on the target side of the
being able to explain all of the audible sounds during
HVLA thrust manipulation, the possibility remains
that several phenomena may be occurring simul-
taneously. Notably, Shekelle57 suggested HVLA
thrust manipulation may affect the following patho-
anatomic lesions: (1) “release of entrapped synovial
folds”, (2) “disruption of intra- or peri-articular adhe-
sions”, (3) “unbuckling of motion segments that have
undergone disproportionate displacements”, and/or
(4) “sudden stretching of hypertonic muscle”.57
Duration of an individual cavitation
The mean duration of a single cavitation during cer-
vicothoracic HVLA thrust manipulation was 4.13
ms (95% CI: 0.82, 7.46) in this study. This value
approximates the 4 ms duration reported by Reggars
and Pollard24 for the “average length of joint crack
sounds” and the 5.66 ms duration reported by Dun-
ning et al26 for the mean duration of a “single pop”
during upper cervical thrust manipulation. Never-
theless, Herzog et al23 reported triphasic “cavitation
signals” with a mean duration of 20 ms, however, it
is unclear whether this value represents single or
multiple cavitation sounds. Unlike previous stud-
ies,23,24,26 the time interval between the beginning
of the ascent of the first energy burst and the end
of the descent of the last energy burst of a cavita-
tion event was calculated and used for the duration
of a single pop in this study. Therefore, the interval
was representative of the duration of 252 individual
cavitation sounds (i.e. popping or cracking noises)
detected during 58 cervicothoracic HVLA thrust
manipulation procedures.
Duration of the thrust procedure
Similar to Dunning et al,26 but unlike three previous
studies,23,55,56 the time interval between the begin-
ning of first cavitation and the end of the last cavita-
tion was used to represent the duration of the actual
thrusting procedure from onset to arrest in the cur-
rent study; nevertheless, the mean duration of a
single cervicothoracic HVLA thrust manipulation
was found to be 60.77 ms (95%CI 28.25, 97.42), a
value that is slightly shorter but still consistent with
Triano56 (135 ms), Herzog et al23 (80-100 ms), Ngan
et al55 (158 ms) and Dunning et al26 (97 ms). Notably,
Triano56 measured the duration of the thrusting pro-
cedure by analyzing force-time history graphs for a
The International Journal of Sports Physical Therapy | Volume 12, Number 4 | August 2017 | Page 652
multiple frequencies, neither the cavitation hypoth-
esis (i.e. intra-articular gas bubble collapse) nor the
tribonucleation hypothesis (i.e. cavity inception
within synovial fluid) alone appear able to explain
all of the audible sounds during HVLA thrust manip-
ulation, and the possibility remains that several phe-
nomena may be occurring simultaneously.
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... Identificare valori normativi per la cinematica e la biomeccanica delle manipolazioni vertebrali nelle differenti regioni corporee è necessario al fine di comprendere i parametri fisici (ad es. velocità, accelerazione ecc.) (65,66) e le abilità specifiche per erogare questo intervento (67)(68)(69)(70)(71)(72)(73)(74)(75)(76)(77)(78)(79). La manipolazione spinale, in letteratura, viene definita High Velocity Low Amplitude (HVLA) Thrust. ...
... Con la tecnologia disponibile purtroppo, non è stato possibile discriminare la struttura responsabile della genesi del rumore articolare. Tuttavia, gli autori hanno evidenziato delle importanti caratteristiche del popping sound: su 252 pop totali registrati, infatti, molti sono stati ricondotti a eventi caratterizzati da singoli picchi di energia, altri invece, da picchi multipli di energia all'interno del medesimo pop (66). Inoltre, sono stati osservati fenomeni di frequenze differenti all'interno della stessa registrazione. ...
... discendente dello stesso picco (66,92). L'intero processo manipolativo invece, è compreso tra la parte iniziale della fase ascendente del primo evento di produzione del pop sound e la parte finale della fase discendente dell'ultimo popping sound (66,92). ...
... Manual therapy techniques have been well described in the literature over the years and date back well beyond the scope of this study [2][3][4][5][6][7][8][9][10][11][12]. The benefits of HVLA thrust techniques for spinal and extremity pain or dysfunction are widely recognized in the literature. ...
... For example, reduction in pain and improved function following HVLA thrust manipulation to the cervicothoracic region has been widely reported in patients with neck pain and shoulder pain [2,[5][6][7]10]. Achieving isolated specific facet cavitation is not consistent with the literature when applying segment-specific HVLA techniques throughout the upper and lower cervical, cervicothoracic, thoracic, and lumbar spine regions [2][3]9]. Though joint cavitation at an intended facet may not be as specific as our intention to treat, the application of HVLA techniques at the cervicothoracic spine should be. ...
... Though joint cavitation at an intended facet may not be as specific as our intention to treat, the application of HVLA techniques at the cervicothoracic spine should be. The lateral break cervicothoracic joint HVLA maneuver has been well described [3]. Utilization of the lateral break maneuver at the cervicothoracic junction produced cavitation that was significantly more likely to occur unilaterally and on the side contralateral to the short lever applicator contact [3]. ...
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Currently, there is a paucity of studies that describe prone cervicothoracic joint high-velocity low-amplitude (HVLA) thrust techniques using an anatomically accurate, biomimetic three-dimensional (3D) spine model for educational demonstration. The purpose of this technical report was to present a learning model for two prone cervicothoracic HVLA thrust techniques using a 3D model, review intersegmental mobility observed on a 3D spine model with application of the techniques, and lastly discuss potential applications of this learning model.
... 25 Notably, Kawchuk et al 15 found a void within the joint that persists after the sound production that could explain the ZJ gapping after HVLA thrust manipulation observed by Cramer et al. 24,25 More recently, another research group tried to analyze the PS phenomenon using sound wave signals processed by a time-frequency analysis. 8,26 The authors observed that the sound was composed of single and multiple energy releases (ie, single versus multi-peak sounds). Furthermore, they identified high and low sounds and sounds of multiple frequencies. ...
... The sound wave signals were recorded by skin-mounted microphones (ie, on C1-2 segment) and accelerometers (ie, on T1-2 segment) and then processed by using the short-time Fourier transform and analyzing the produced spectrograms. 8,26 Time-frequency analysis is a widely adopted method in monitoring different fields such as radar signals, 29,30 myoelectric signals, 31,32 and sound signals. 33,34 The aforementioned studies 2,4 did not apply it because they were aimed at investigating the PS phenomenon only by sensing the presence or absence of sound signals (ie, the actual sound releases) and then counting the number of reported PSs and determining their location. ...
... As described in our previous studies, 25,26 the duration of the thrusting procedure was considered the time interval between the beginning of first pop and the end of the last pop (Fig 6). ...
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Objective: The purpose of this study was to determine from which side of the spine the popping sound (PS) emanates during side-lying, rotatory high-velocity low-amplitude (HVLA) thrust manipulation directed to the L5-S1 articulation using a time-frequency analysis. Secondary aims were to calculate the average number of PSs, the duration of lumbar thrust manipulation, and the duration of a single PS. Methods: Thirty-four asymptomatic participants received 2 lumbar HVLA thrust manipulations targeting the right and left L5-S1 articulations. Two high sampling rate accelerometers were secured bilaterally 25 mm lateral to the midline of the L5-S1 interspace. For each manipulation, 2 audio signals were extracted and singularly processed via spectrogram calculation to obtain the release of energy over time on each side of the lumbosacral junction. Results: During 60 HVLA thrust manipulations, it was measured a total of 320 PSs. Of those PSs, 176 occurred ipsilateral and 144 occurred contralateral to the targeted L5-S1 articulation; that is, the PS was no more likely to occur on the upside than the downside facet after right or left rotatory L5-S1 HVLA thrust manipulation. Moreover, PSs occurring on both sides at the same time were detected very rarely (ie, 2% of cases) with the lumbar HVLA thrust manipulations. The mean number of audible PSs per lumbosacral HVLA thrust manipulation was 5.27 (range 2-9). The mean duration of a single manipulation was 139.13 milliseconds (95% confidence interval: 5.61-493.79), and the mean duration of a single PS was 2.69 milliseconds (95% confidence interval: 0.95-4.59). Conclusion: Based on our findings, spinal manipulative therapy practitioners should expect multiple PSs that most often occur on the upside or the downside facet articulations when performing HVLA thrust manipulation to the lumbosacral junction (ie, L5-S1). However, whether the multiple PSs found in this study emanated from the same joint or adjacent ipsilateral or contralateral facet joints remains unknown. A single model may not necessarily be able to explain all of the audible sounds during HVLA thrust manipulation.
... 14 However, the phenomena of tribonucleation and cavitation alone do not explain all possible sounds from a TM. More recently, other authors 3,16,17 analyzed sound wave signals processed by a time-frequency analysis observing that the sound was composed of single and multiple energy releases and frequencies, suggesting multiple mechanisms underlying the popping sound phenomenon. 3,16,17 The audible popping sound is hypothesized to be the main characteristic of an effective TM. ...
... More recently, other authors 3,16,17 analyzed sound wave signals processed by a time-frequency analysis observing that the sound was composed of single and multiple energy releases and frequencies, suggesting multiple mechanisms underlying the popping sound phenomenon. 3,16,17 The audible popping sound is hypothesized to be the main characteristic of an effective TM. 2,[18][19][20][21][22][23][24] It is also hypothesized that the absence of a popping sound during TM potentially increases the patient's perception of an ineffective intervention. ...
Article
Objective: The purpose of this study was to assess whether beliefs about the origin of the popping sound and the effects of thrust manipulation (TM) were in agreement with current scientific evidence and whether a practitioner's explanation could influence patient beliefs of theoretical mechanisms. Methods: A cross-sectional online survey was conducted in Italy from January 7, 2019 to April 20, 2019. The questionnaire was sent to 900 Italian adults through online recruitment, including people with and without a history of manipulation, such as given by physiotherapists, chiropractors, osteopaths, and manual medicine physicians to manage musculoskeletal disorders. The questionnaire consisted of 11 multiple-choice questions and could be completed within 15 weeks. The Likert scale was used to investigate participants' attitudes. Sex and previous experience of TM variables were evaluated using a Student's t-test; a 1-way F analysis of variance test was performed to evaluate age, educational qualification, and the professional who performed the TM. Results: We retrieved 478 questionnaires, including 175 participants with no TM history and 303 with TM history. There were 31% of participants (n = 94) with a history of TM who reported they did not receive explanations regarding manipulation. The participants' beliefs mostly disagreed with the current hypotheses provided by the scientific literature on the theoretical mechanisms of popping sound (tribonucleation and cavitation). There were 9.9% (n = 30) of participants who answered "realignment of bone positional fault" to explain the mechanism behind TM. There was a high degree of agreement with the belief that the popping sound should be present for a successful TM (respectively, 2.8 standard deviation [SD; 1.2] and 2.6 SD [1.2] for TM+ and TM- participants). No statistically significant differences were found between participants with and without a history of TM. Conclusion: The participants in this study reported a belief that popping was related to effectiveness of TM. A high percentage of this sample had beliefs about TM mechanisms for the audible popping sound that were inconsistent with current literature. Beliefs were similar between groups, suggesting that instructions given by TM practitioners did not seem to be an influence on these patients' beliefs.
... It is challenging to compare these numbers as the 'patients' in our study were pain free college aged students and the patients receiving the SIJ regional manipulation in the research by Grindstaff et al. 40 were experiencing musculoskeletal dysfunction. One hundred percent of the students in this study achieved a cavitation on either their first or second attempt with the CT junction HVLAT technique, while Dunning et al. 30 describe a 100% cavitation rate on their first attempt. ...
Article
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Purpose A high-velocity low-amplitude thrust joint manipulation (HVLAT) is an intervention used by clinicians to treat spine pain. HVLAT is an entry-level skill included in the curriculum of physical therapist education programs. The objective of this study was to investigate the effects of utilizing a motor learning theory assisted teaching strategy on physical therapy student HVLAT confidence and skill acquisition as compared to a traditional lab. Methods Thirty physical therapy students were divided into two groups. One group received a traditional lab. The other group received a lab involving sequential partial task practice (SPTP) strategy in which students engaged in partial task practice over several repetitions with different partners. Student confidence and skill acquisition was determined through comparison of pretest and posttest surveys and performance on skills assessments. Results The traditional lab and SPTP lab groups demonstrated similar response from pretest to posttest related to their HVLAT confidence. Student grades on their skills assessment measuring skill acquisition showed no significant differences between the lab groups. Discussion The findings suggest that the SPTP lab strategy was as effective as a traditional lab structure for developing physical therapy student HVLAT confidence and skill acquisition. The majority of students in both lab groups reached a level of confidence that allowed them to feel comfortable teaching someone else these HVLAT skills. It is up to the instructors involved in delivering HVLAT content in physical therapist education programs to determine what learning activities are best suited to meet their specific objectives.
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Hintergrund: Physiotherapeut*Innen verwenden die spinale Gelenkmanipulation u.a. zur Behandlung bestimmter arthrogener Dysfunktionen. Postmanipulativ verändert sich neben dem Schmerz- und Beweglichkeitsstatus häufig das Aktivierungsmuster bestimmter Muskeln. Ziele: Detektion kurzfristiger Auswirkungen spinaler Gelenkmanipulation auf die EMG-Aktivität, Schmerz und die aktive Beweglichkeit bei erwachsenen Menschen und der Unterschied zu anderen therapeutischen Maßnahmen. Design: Systematisches Review Informationsquellen: Primäre Informationsquellen (MEDLINE, EMBASE, CINAHL, PEDro), sekundäre Informationsquellen (Open Grey, Dart-Europe, Expertenbefragungen, clinicaltrials.gov, ICTRP, Referenzlisten) Auswahlkriterien: Design (RCTs, randomisierte Cross-Over-Studien), Spezies (Humanstudien), Sprachen (Deutsch, Englisch), Publikationszeitraum (01/2000 – 03/2020) Studienbewertung: Evidenzklassen nach CEBM (relative Beweiskraft), PEDro-Skala (methodologische Qualität), modifizierte CIRCLe SMT (interventionsspezifische Berichterstattung) Ergebnisse: Von insgesamt 901 Treffern wurden 13 Primärarbeiten mit akkumuliert 443 Proband*Innen zur Bearbeitung dieser systematischen Übersichtsarbeit inkludiert. Die vorliegende Arbeit konnte keine generalisierbare Aussage über die kurzfristigen Auswirkungen spinaler Gelenkmanipulation auf die EMG-Aktivität, Schmerzen und die aktive Beweglichkeit bei erwachsenen Menschen liefern, indizierte aber schwache Evidenz für jeden Ergebnisparameter. Das detektierte postmanipulative Aktivierungsverhalten der Muskulatur konnte sowohl exzitatorisch als auch inhibitorisch sein. Mittels Subgruppenanalysen wurde ein potentieller Einfluss der Krankheitsbilder auf die postmanipulative EMG-Aktivität eruiert. Es gibt moderate Evidenz dafür, dass eine lumbale Rotationsmanipulation bei Patient*Innen mit nichtspezifischen Rückenschmerzen zu einer signifikanten Reduktion der EMG-Aktivität der paravertebralen Muskulatur während des Haltens in voller Rumpfflexion und der Extensionsbewegung aus der vollen Flexion führt. Ebenso besteht moderate Evidenz dafür, dass eine lumbopelvine Rotationsmanipulation der betroffenen Seite bei Patient*Innen mit einem Patellofemoralen Schmerzsyndrom zu einem signifikanten An-stieg der EMG-Aktivität des M. gluteus medius führt. Schwache Evidenz besteht da-für, dass segmentspezifische Manipulationen im Bezug auf die EMG-Aktivität und Schmerzen keinen Benefit im Vergleich zu global ausgeführten Techniken bringen. Unklar bleibt, ob eine spinale Gelenkmanipulation kurzfristig signifikante Benefits im Vergleich zu Placebo-, Pseudoplacebo- oder anderen therapeutischen Kontrollinterventionen im Bezug auf die EMG-Aktivität, Schmerzen und die aktive Beweglichkeit bei erwachsenen Menschen bietet. Limitationen: Die methodologische Qualität über die Studien hinweg lag bei 5,77/10 Punkten und war mäßig. Das Risiko für Performance Bias über die Studien hinweg war sehr hoch. Das Risiko für Spectrum bzw. Detection Bias war moderat. Das Risiko der Verzerrungen aufgrund der interventionsspezifischen Berichterstattung über die Studien hinweg wurde als gering angesehen. Die individuellen Primär-arbeiten waren hinsichtlich der wichtigsten Studienmerkmale heterogen. Schlussfolgerungen: Die spinale Gelenkmanipulation soll allenfalls supportiv zur überwiegend aktiven Behandlung von veränderten muskulären Aktivierungsmustern, Schmerzen und Bewegungseinschränkungen eingesetzt werden. Die spinale Gelenkmanipulation eignet sich, um Patient*Innen bereits innerhalb einer Therapieeinheit die Adaptabilität des neuromuskuloskelettalen Systems bzw. die Modifikationsmöglichkeit für Symptome und Bewegung zu visualisieren. Somit kann weitere passive, assistive oder idealerweise aktive Bewegung fazilitiert werden. Registrationsnummer: PROSPERO - CRD42020160690 Stichworte: Spinale Gelenkmanipulation, EMG, Schmerz, aktive Beweglichkeit
Article
Background/purpose A spinal cord injury without radiographic abnormality (SCIWORA) is a relatively uncommon event that occurs in children following cervical trauma primarily due to sports-related injuries and abuse. Case description This case report describes an 11-year-old wrestler that developed signs and symptoms consistent with a SCIWORA following neck trauma during competition. Despite all diagnostic tests being inconclusive, the patient demonstrated increased cervical, thoracic, and lumbar paraspinal tone along with pain, loss of sensation, loss of mobility, and weakness of the lower extremities. As a result, the patient was confined to a wheelchair and required maximum assistance to transfer and ambulate with a walker. The patient was referred to physical therapy nine days after the traumatic event, where he received interferential current with moist heat, myofascial release of paraspinal muscles, functional exercise, gait training, and spinal manipulative therapy targeting the cervical, thoracic, and lumbar vertebrae. Outcome After 13 physical therapy treatments over 5-weeks, the patient was able to ambulate independently and perform all activities of daily living without pain or limitation. The following case report outlines this patient's successful journey toward recovery. Conclusion This case report suggests that spinal manipulative therapy may be a safe and effective component of a multi-modal treatment strategy for patients with signs and symptoms consistent with SCIWORA. Moreover, spinal manipulative therapy may be considered a useful treatment in some pediatric patients. However, this report describes a single patient, and further research is required on the use of spinal manipulation in this patient population.
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Study Design Secondary analysis of a randomized controlled trial. Background Prognostic variables identifying patients with shoulder pain who are likely to respond to cervicothoracic (CT) manipulation have been reported, however they have yet to be validated. Objective To examine the validity of previously reported prognostic variables in predicting which patients with shoulder pain will respond to cervicothoracic manipulation. Methods Participants (n=140) with a report of shoulder pain were randomly assigned to receive either 2 sessions of range of motion (ROM) exercises plus 6 sessions of stretching and strengthening exercises (Ex group), or 2 sessions of CT manipulation and ROM exercises followed by 6 sessions of stretching and strengthening exercise (MT+Ex group). Outcomes of disability (Shoulder Pain and Disability Index) and pain (Numeric Pain Rating Scale) were collected at baseline, 1-week, 4-weeks and 6-months. Time, treatment group and status of predictor variables, and 2-way and 3-way interactions were analyzed using linear mixed-model with repeated measures. Results There were no significant 3-way interactions for either disability (p=0.27) or pain scores (p=0.70) for time, group, and predictor status for any of the predictor variables. Conclusion The results of the current study did not validate the previously identified prognostic variables, therefore we cannot support using these in clinical practice. Further "updating" of the existing prediction rule may be warranted and could potentially result in new prognostic variables and improved generalizability. Limitations of the study include that mean duration of symptoms was greater than 2 years, and loss to follow-up at 6 months was 19%. Level of Evidence Prognosis, Level 1b. Trial prospectively registered March 30, 2012 at www.clinicaltrials.gov (NCT01571674) J Orthop Sports Phys Ther, Epub 3 Mar 2017. doi:10.2519/jospt.2017.7100.
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TTBACKGROUND: Cervicothoracic manual therapy has been shown to improve pain and disability in individuals with shoulder pain, but the incremental effects of manual therapy in addition to exercise therapy have not been investigated in a randomized controlled trial. TTOBJECTIVES: To compare the effects of cervicothoracic manual therapy and exercise therapy to those of exercise therapy alone in individuals with shoulder pain. TTMETHODS: Individuals (n = 140) with shoulder pain were randomly assigned to receive 2 sessions of cervicothoracic range-of-motion exercises plus 6 sessions of exercise therapy, or 2 sessions of high-dose cervicothoracic manual therapy and range-of-motion exercises plus 6 sessions of exercise therapy (manual therapy plus exercise). Pain and disability were assessed at baseline, 1 week, 4 weeks, and 6 months. The primary aim (treatment group by time) was examined using linear mixedmodel analyses and the repeated measure of time for the Shoulder Pain and Disability Index (SPADI), the numeric pain-rating scale, and the shortened version of the Disabilities of the Arm, Shoulder and Hand questionnaire (QuickDASH). Patientperceived success was assessed and analyzed using the global rating of change (GROC) and the Patient Acceptable Symptom State (PASS), using chi-square tests of independence. TTRESULTS: There were no significant 2-way interactions of group by time or main effects by group for pain or disability. Both groups improved significantly on the SPADI, numeric pain-rating scale, and QuickDASH. Secondary outcomes of success on the GROC and PASS significantly favored the manual therapy-plus-exercise group at 4 weeks (P = .03 and P<.01, respectively) and on the GROC at 6 months (P = .04). TTCONCLUSION: Adding 2 sessions of high-dose cervicothoracic manual therapy to an exercise program did not improve pain or disability in patients with shoulder pain, but did improve patientperceived success at 4 weeks and 6 months and acceptability of symptoms at 4 weeks. More research is needed on the use of cervicothoracic manual therapy for treating shoulder pain. TTLEVEL OF EVIDENCE: Therapy, level 1b. Prospectively registered March 30, 2012 at www. ClinicalTrials.gov (NCT01571674). J Orthop Sports Phys Ther 2016;46(8):617-628.
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Cracking sounds emitted from human synovial joints have been attributed historically to the sudden collapse of a cavitation bubble formed as articular surfaces are separated. Unfortunately, bubble collapse as the source of joint cracking is inconsistent with many physical phenomena that define the joint cracking phenomenon. Here we present direct evidence from real-time magnetic resonance imaging that the mechanism of joint cracking is related to cavity formation rather than bubble collapse. In this study, ten metacarpophalangeal joints were studied by inserting the finger of interest into a flexible tube tightened around a length of cable used to provide long-axis traction. Before and after traction, static 3D T1-weighted magnetic resonance images were acquired. During traction, rapid cine magnetic resonance images were obtained from the joint midline at a rate of 3.2 frames per second until the cracking event occurred. As traction forces increased, real-time cine magnetic resonance imaging demonstrated rapid cavity inception at the time of joint separation and sound production after which the resulting cavity remained visible. Our results offer direct experimental evidence that joint cracking is associated with cavity inception rather than collapse of a pre-existing bubble. These observations are consistent with tribonucleation, a known process where opposing surfaces resist separation until a critical point where they then separate rapidly creating sustained gas cavities. Observed previously in vitro, this is the first in-vivo macroscopic demonstration of tribonucleation and as such, provides a new theoretical framework to investigate health outcomes associated with joint cracking.
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To explain the concept and procedure of random allocation as used in a randomized controlled study. We explain the general concept of random allocation and demonstrate how to perform the procedure easily and how to report it in a paper.
Book
Somatic dysfunction. Diagnosis. Classification of osteopathic techniques. Contra-indications and precautions. Indirect technique. Modifying factors in technique. Handling. Operator posture and stance. Applied technique. Principles of locking. Exercises for developing technical skill. Techniques for the lumbar area. Techniques for the sacro-iliac area. Techniques for the gluteal region and coccyx. Techniques for the thoraco-lumbar junction area. Techniques for the thoracic spine. Techniques for the thoracic cage and ribs. Techniques for the scapulo-thoracic area. Techniques for the cervico-thoracic junction area. Techniques for the cervical area. Techniques for the occipital area. Techniques for the sinuses and tempero-mandibular joints. Techniques for the clavicle area. Techniques for the shoulder area. Techniques for the elbow area. Techniques for the forearm area. Techniques for the wrist and hand. Techniques for the hip area. Techniques for the thigh area. Techniques for the knee area. Techniques for the calf area. Techniques for the foot.
Article
Joint mobilization and manipulation are commonly used by physiotherapists and chiropractors for the treatment of spinal and peripheral joint pain. There are, however, few quantitative studies about the effects of these manoeuvres on joint function. We studied and compared the effects of manipulation and mobilization on metacarpophalangeal coaptation and mobility. Sixty-two third metacarpophalangeal (MCP) joints were studied radiographically before and after applying a long-axis distraction force across the joint space. An audible crack and radiographically visible gas arthrogram were highly associated with a significant decrease in joint coaptation under tension for the manipulated joints. There was no evidence of a gas arthrogram, audible crack, or change in coaptation for the mobilized joints. In a further study, 62 MCP joints were randomly allocated to either manipulation or mobilization. The treatment was followed by blind assessment of passive flexion of the treated joint. The manipulated group demonstrated a significant increase in passive MCP joint flexion over the mobilized group. These results show that manipulation and mobilization are distinct therapies with different effects on joint function and that these effects in clinical trials of manual therapy should not be considered equivalent, as they have been in the past.
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Objective: The purpose of this study was to compare the effects of thoracic thrust manipulation vs thoracic non-thrust mobilization in patients with bilateral chronic mechanical neck pain on pressure pain sensitivity and neck pain intensity. Methods: Fifty-two patients (58% were female) were randomly assigned to a thoracic spine thrust manipulation group or of thoracic non-thrust mobilization group. Pressure pain thresholds (PPTs) over C5-C6 zygapophyseal joint, second metacarpal, and tibialis anterior muscle and neck pain intensity (11-point Numerical Pain Rate Scale) were collected at baseline and 10 minutes after the intervention by an assessor blinded to group allocation. Mixed-model analyses of variance (ANOVAs) were used to examine the effects of the treatment on each outcome. The primary analysis was the group * time interaction. Results: No significant interactions were found with the mixed-model ANOVAs for any PPT (C5-C6: P>.252; second metacarpal: P>.452; tibialis anterior: P>.273): both groups exhibited similar increases in PPT (all, P<.01), but within-group and between-group effect sizes were small (standardized mean score difference [SMD]<0.22). The ANOVA found that patients receiving thoracic spine thrust manipulation experienced a greater decrease in neck pain (between-group mean difference: 1.4; 95% confidence interval, 0.8-2.1) than did those receiving thoracic spine non-thrust mobilization (P<.001). Within-group effect sizes were large for both groups (SMD>2.1), and between-group effect size was also large (SMD = 1.3) in favor of the manipulative group. Conclusions: The results of this randomized clinical trial suggest that thoracic thrust manipulation and non-thrust mobilization induce similar changes in widespread PPT in individuals with mechanical neck pain; however, the changes were clinically small. We also found that thoracic thrust manipulation was more effective than thoracic non-thrust mobilization for decreasing intensity of neck pain for patients with bilateral chronic mechanical neck pain.
Article
Study design: Case report. Background: Thoracic spine thrust manipulation has been shown to be an effective intervention for individuals experiencing mechanical neck pain. Case description: The patient was a 46-year-old woman referred to outpatient physical therapy 2 months following multiple-level anterior cervical discectomy and fusion. At initial evaluation, primary symptoms consisted of frequent headaches, neck pain, intermittent referred right elbow pain, and muscle fatigue localized to the right cervical and upper thoracic spine regions. Initial examination findings included decreased passive joint mobility of the thoracic spine, limited cervical range of motion, and limited right shoulder strength. Outcome measures consisted of the numeric pain rating scale, the Neck Disability Index, and the global rating of change scale. Treatment consisted of a combination of manual therapy techniques aimed at the thoracic spine, therapeutic exercises for the upper quarter, and patient education, including a home exercise program, over a 6-week episode of care. Outcomes: Immediate reductions in cervical-region pain (mean ± SD, 2.0 ± 1.1) and headache (2.0 ± 1.3) intensity were reported every treatment session immediately following thoracic spine thrust manipulation. At discharge, the patient reported 0/10 cervical pain and headache symptoms during all work-related activities. From initial assessment to discharge, Neck Disability Index scores improved from 46% to 16%, with an associated global rating of change scale score of +7 ("a very great deal better"). Discussion: This case report describes the immediate and short-term clinical outcomes for a patient presenting with symptoms of neck pain and headache following anterior cervical discectomy and fusion surgical intervention. Clinical rationale and patient preference aided the decision to incorporate thoracic spine thrust manipulation as a treatment for this patient. Level of Evidence Therapy, level 4.