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Unformatted text preview: BMC Musculoskeletal Disorders BioMed Central Open Access Research article An investigation into the validity of cervical spine motion palpation
using subjects with congenital block vertebrae as a 'gold standard'
Barry K Humphreys*1, Marianne Delahaye2 and Cynthia K Peterson1
Address: 1Graduate Education and Research, Canadian Memorial Chiropractic College, 1900 Bayview Avenue, Toronto, Ontario, Canada and
2Research Department, Anglo-European College of Chiropractic (AECC), 13-15 Parkwood Road, Bournemouth, England
Email: Barry K Humphreys* - firstname.lastname@example.org; Marianne Delahaye - email@example.com; Cynthia K Peterson - firstname.lastname@example.org
* Corresponding author Published: 15 June 2004
BMC Musculoskeletal Disorders 2004, 5:19 Received: 21 April 2004
Accepted: 15 June 2004 This article is available from: http://www.biomedcentral.com/1471-2474/5/19
© 2004 Humphreys et al; licensee BioMed Central Ltd. This is an Open Access article: verbatim copying and redistribution of this article are permitted in
all media for any purpose, provided this notice is preserved along with the article's original URL. Abstract
Background: Although the effectiveness of manipulative therapy for treating back and neck pain has been
demonstrated, the validity of many of the procedures used to detect joint dysfunction has not been
confirmed. Practitioners of manual medicine frequently employ motion palpation as a diagnostic tool,
despite conflicting evidence regarding its utility and reliability. The introduction of various spinal models
with artificially introduced 'fixations' as an attempt to introduce a 'gold standard' has met with frustration
and frequent mechanical failure. Because direct comparison against a 'gold standard' allows the validity,
specificity and sensitivity of a test to be calculated, the identification of a realistic 'gold standard' against
which motion palpation can be evaluated is essential. The objective of this study was to introduce a new,
realistic, 'gold standard', the congenital block vertebra (CBV) to assess the validity of motion palpation in
detecting a true fixation.
Methods: Twenty fourth year chiropractic students examined the cervical spines of three subjects with
single level congenital block vertebrae, using two commonly employed motion palpation tests. The
examiners, who were blinded to the presence of congenital block vertebrae, were asked to identify the
most hypomobile segment(s). The congenital block segments included two subjects with fusion at the C2–
3 level and one with fusion at C5-6. Exclusion criteria included subjects who were frankly symptomatic,
had moderate or severe degenerative changes in their cervical spines, or displayed signs of cervical
instability. Spinal levels were marked on the subject's skin overlying the facet joints from C1 to C7
bilaterally and the motion segments were then marked alphabetically with 'A' corresponding to C1-2.
Kappa coefficients (K) were calculated to determine the validity of motion palpation to detect the
congenitally fused segments as the 'most hypomobile' segments. Sensitivity and specificity of the diagnostic
procedure were also calculated.
Results: Kappa coefficients (K) showed substantial overall agreement for identification of the segment of
greatest hypomobility (K = 0.65), with substantial (K = 0.76) and moderate (K = 0.46) agreement for
hypomobility at C2-3 and C5-6 respectively. Sensitivity ranged from 55% at the C5-6 CBV to 78% at the
C2-3 level. Specificity of the procedure was high (91 – 98%).
Conclusion: This study indicates that relatively inexperienced examiners are capable of correctly
identifying inter-segmental fixations (CBV) in the cervical spine using 2 commonly employed motion
palpation tests. The use of a 'gold standard' (CBV) in this study and the substantial agreement achieved
lends support to the validity of motion palpation in detecting major spinal fixations in the cervical spine. Page 1 of 6
(page number not for citation purposes) BMC Musculoskeletal Disorders 2004, 5 Background
Practitioners who treat patients with musculoskeletal disorders generally employ a number of manually applied
examination techniques [1,2]. For the cervical spine, these
techniques commonly consist of passive range-of-motion
tests [3-6], pressure over the zygapophyseal joints [7,8],
palpation tenderness [9,10], spinal stiffness [11,12], and
passive intervertebral motion or motion palpation
[13,14]. Active cervical range-of-motion is now commonly measured using mechanical devices [5,6].
In general, manual examination tests are used to detect
and assess mechanical dysfunction of the cervical spine
[15,16]. Test results are also used as clinical indicators for
the application of manual therapy [16,17]. It is theorized
that patients with mechanical neck pain may exhibit any
or all of the findings consisting of increased spinal stiffness, localized muscle and joint pain, and reduced global
as well as intersegmental range-of-motion at the site(s) of
dysfunction. Consequently, active range-of-motion is
used to evaluate global restrictions in cervical spine movement; provocative palpation tests of connective tissues
and zygapophyseal joints to elicit pain from inflamed or
damaged tissues; spinal stiffness tests to measure segmental motion; and intervertebral motion palpation to assess
intersegmental dysfunction in terms of quantity and quality of intersegmental movement .
For any test to be useful in the clinical setting, it needs to
be valid and reliable . Unfortunately many manual
examination tests for the cervical spine have demonstrated only poor to moderate reliability [1-3,5,10,13,14].
However, some recent studies suggest that palpation of
cervical spine tenderness, reduced range of motion and
some forms of motion palpation may be more reliable
than previously reported [2,4,7,13]. There is now some
evidence to suggest that physical impairments, functional
limitations and disability are related in patients with cervical spine dysfunction [4,29].
Dysfunction of the cervical spine is commonly evaluated,
at least in part, using motion palpation techniques. In particular, intersegmental motion palpation has been studied
extensively, but this has been mostly for the lumbar spine
[19-24]. During the 1980 s and early 1990 s, a number of
intra- and interexaminer reliability studies of cervical
spine intersegmental motion palpation were also conducted [25,26]. Results ranged from good to poor, or to
no difference compared to that expected by chance alone
[25,26,30]. Critics suggested variations of results were
mainly due to varying quality of study design and statistical analysis [28-30]. Another major criticism of reliability
studies in general was the lack of an appropriate 'gold
standard' with which to compare the presence or absence
of mechanical dysfunction [31,32]. A recent review of spi- http://www.biomedcentral.com/1471-2474/5/19 nal palpatory diagnostic procedures identified only 3
studies related to the validity of motion palpation .
All of these studies involved the lumbar spine, used
mechanical models and did not incorporate the specific
influence that ligament and muscle attachments would
have on intersegmental motion. Many of these models
were subject to mechanical failure during data collection
[31,34]. Only zygapophyseal joint injections have been
used as an in vivo 'gold standard' for assessing cervical
spine pain [35,36]. Currently no study utilizing a 'gold
standard' has been performed in vivo to evaluate the
validity of cervical spine intersegmental motion
This study proposes a new 'gold standard' of fixation, congenitally blocked (fused) vertebrae (CBV), which is without the limitations of previous studies. When two
adjacent vertebrae are osseously fused from birth, this
joined unit is known as congenital block vertebrae.
Embryologically, congenital block vertebrae are the result
of failure of the normal segmentation process of the
somites during the period of differentiation, at 3–8 foetal
weeks. There is no motion at the level of congenital block
vertebrae, as noted in flexion and extension radiographic
analysis, resulting in excessive mobility and early degenerative changes at the adjacent unfused motion segments
. Single congenital fusions are common anomalies,
found most often at the C2-3 and C5-6 levels  (Figure
The purpose of this study is to investigate the validity of
motion palpation of the cervical spine in subjects with
congenital block vertebrae. Methods
Participants / Subjects
Three subjects previously attending the Anglo-European
College of Chiropractic (AECC) clinic, who had been
diagnosed with a single level congenital fusion in the cervical spine, were included in this study. Two of these individuals had fusion at the C2-3 level and one was fused at
C5-6. None of these subjects were frankly symptomatic at
the time of data collection, had moderate or severe degenerative changes in their cervical spines, or displayed signs
of cervical instability. Prior to their participation, the
study risks, benefits and examination procedures were
described to them. All subjects gave written consent to
Twenty 4th year students at the AECC agreed to examine
the cervical spines of the three subjects. Each examiner
was instructed to perform motion palpation as taught in
the undergraduate programme and to report the 'most
fixed' motion segment. All examiners had received three Page 2 of 6
(page number not for citation purposes) BMC Musculoskeletal Disorders 2004, 5 http://www.biomedcentral.com/1471-2474/5/19 Figure 2
Palpation procedure for intersegmental motion in rotation
Palpation procedure for intersegmental motion in rotation Figure 1
Congenital fusion of C2-3
Congenital fusion of C2-3 Figure
Palpation procedure for intersegmental motion in lateral
Palpation procedure for intersegmental motion in lateral
flexion years of motion palpation training as well as a review of
the procedure and revision handouts prior to participation. Examiners were given no information about the subjects and were thus unaware that each had congenital
block vertebra. marks. The intervertebral motion units were then marked
alphabetically on the patient, "A" corresponding to C1-2,
"B" to C2-3, etc. Patients were requested not to engage in
verbal/visual communication with the examiners. Procedures
With the patient seated and their head in a neutral position, marks were drawn on the skin overlying the facet
joints of C1 to C7 bilaterally. This was done by using the
occiput, and the C2 and C7 spinous processes as land- Each examiner independently evaluated the subjects for
fixations, by palpating their cervical spines from C1 to C7
while the subject was in a seated position. Palpation was
done first in rotation (Figure 2) and then in lateral flexion
(Figure 3). The exact level of the most severe fixation find- Page 3 of 6
(page number not for citation purposes) BMC Musculoskeletal Disorders 2004, 5 http://www.biomedcentral.com/1471-2474/5/19 Table 1: Validity Results All Blocks
Kappa Values Specificity
Sensitivity C2-3 Block C5-6 Block K = 0.675
SE = 0.041
Z = 17.067
74% K = 0.756
SE = 0.045
Z = 16.823
78% K = 0.460
SE = 0.091
Z = 5.039
55% K = Kappa coefficient SE = Standard Error Z = Test Statistic Specificity is the ability to correctly identify non-fixed segments Sensitivity is the ability
to detect a fixation if present ing was demonstrated to one of the authors. If more than
one fixation was identified, the examiners were asked to
determine which of the fixations they considered to be the
'most hypomobile', and this information was recorded.
Examiners were instructed not to discuss their palpatory
findings with each other. examiners could identify non-fixed segments most of the
time. The sensitivity was 74% overall (55% for the C5-6
block, and 78% at C2-3). It was interesting to note that in
patient number 2, many examiners identified an upper
cervical segment as the most hypomobile, despite the CBV
existing at the C5-6 level. Outcome Measures
The validity of the motion palpation procedures was
assessed comparing the examiners' identified 'most hypomobile' level to the 'gold standard' level of the congenital
block vertebra. The calculation of Kappa coefficients was
performed to determine whether actual inter-examiner
agreements reflected concordance beyond chance. A
Kappa value < 0.00 = poor agreement, 0.01 – 0.20 = slight
agreement, 0.21 – 0.40 = fair agreement, 0.41 – 0.60 =
moderate agreement, 0.61 – 0.80 = substantial agreement,
and 0.81 – 1.00 = almost perfect agreement (26). Kappa
coefficients were also calculated for the two different levels of CBV, in order to distinguish whether the data could
demonstrate any difference in validity of motion
palpation in detecting a 'fixation' at different spinal levels
(C2-3 compared to C5-6). Discussion The specificity and sensitivity of these motion palpation
procedures was also determined. Sensitivity in this study
was defined as the ability to detect a fixation if it is
present, and specificity was defined as the ability to correctly identify non-fixed segments. Results
The sensitivity, specificity and Kappa coefficients were calculated from the individual examiner's 'most hypomobile' finding compared to the CBV gold standard (Table
1). These results indicate a high rate of correct 'fixation'
identification. The Kappa values for all patients (K =
0.675) indicated substantial agreement beyond chance.
The results from the two subjects with C2-3 congenital
fusion was even higher, K = 0.756, whilst agreement for
palpation of the subject with the congenital fusion at the
C5-6 level was moderate (K = 0.460). The specificity was
also high (91% for C5-6 and 98% at C2-3), indicating that This study was unique in employing an in-vivo gold
standard of fixation in the form of congenital block vertebrae. It allowed the validity of motion palpation in the
detection of segmental hypomobility to be evaluated,
whilst omitting some of the experimental design
limitations, which confined and confounded the previous
Although previous studies have cast significant doubt on
the reliability and validity of motion palpation for the
diagnosis of a manipulable lesion [21-26,28], clinicians
still continued to use this procedure in their practices.
Their clinical judgment appeared to take precedence over
the research findings. Perhaps these clinicians, functioning in the reality of the practice situation, sensed the
limitations of the research settings and still felt that they
were able to detect the individual fixation/s. The results of
this study suggest that even student examiners, with less
experience than practicing clinicians, were able to detect
the presence or absence of 'fixation' in the cervical spine
using specific motion palpation techniques in lateral flexion and rotation. The overall Kappa value of K = 0.675
represents substantial agreement beyond chance. These
positive findings support the clinical use of motion palpation, and are arguably the most significant to date, since
previous investigations have provided little evidence of
the accuracy, validity or reliability of this procedure .
The degree of agreement reflected in these results may be
accounted for by the use of an in-vivo gold standard,
which closely approximates a true fixation. Not only is no
motion allowed at the level of the CBV, but as previously
described, the anomaly can result in increased motion
and potential instability at adjacent motion segments Page 4 of 6
(page number not for citation purposes) BMC Musculoskeletal Disorders 2004, 5 . The relative 'fixation' feel at the CBV would therefore
be enhanced, and its detection further facilitated. The high
Kappa values obtained in this study may also have been
assisted by the marking of the IVMUs on the subjects.
The results, while not flawless, are encouraging in considering that even the most fundamental orthopaedic procedures have been shown to have less than perfect specificity
and sensitivity . An attempt was made in this study to
limit variation in palpatory technique used by the examiners, in order to increase the tests reproducibility. The use
of examiners with the same training and experience, as
well as specific instruction as to the techniques to be used,
served to standardize the motion palpation procedures
performed, and may be one factor which contributed to
the relatively high specificity and sensitivity scores.
Kappa coefficients for the different levels of CBV were also
calculated to determine whether there was a difference
between the validity of motion palpation at the different
levels of the cervical spine. Palpation of the two patients
with C2-3 CBV indicated substantial agreement (K =
0.756), whilst moderate agreement (K = 0.460) was indicated in the subject with the C5-6 block. In a normal cervical spine there is greater motion allowed at the C5-6
motion segment than at more superior segments, and one
might therefore expect a total lack of motion at this C5-6
level to be easier to identify. However, this increased
motion at C5-6 is particularly in the directions of flexion
and extension, whereas the motion palpation evaluated in
this study was in rotation and lateral flexion. Additionally,
most people have more muscle and other overlying soft
tissues in the mid and lower cervical spine through which
to palpate, as compared to the more superficial C2-3
region. This may have contributed to the difference in
results. It must also be pointed out that only 3 patients
were included in this study, with only one having CBV at
the C5-6 level. Therefore the discrepancy in these results
may simply have been due to idiosyncrasies in the individual patients.
It was interesting to note that when palpating the subject
with the C5-6 block, many examiners identified an upper
cervical segment (C1-2 or C2-3) as the most hypomobile.
It is possible that a true vertebral 'dysfunction' was present
at the higher segment, causing a number of examiners to
implicate it as their most hypomobility finding. The
choice of this segment over the CBV caused the validity of
motion palpation as assessed by this project design to
decrease. Although it is unlikely that the kinesiopathology
of a true vertebral dysfunction/fixation would affect
greater hypomobility than a congenital fusion, it is possible that other manifestations of the 'joint dysfunction
complex' were evident and detected by examiners. Despite
simply being requested to identify fixation, other indica- http://www.biomedcentral.com/1471-2474/5/19 tors of a joint dysfunction were being appreciated by the
examiners. This suggests that when using motion palpation, examiners integrate the sense of kinesiopathology,
with an appreciation of temperature change, muscle
tension, tenderness, swelling, non-verbal pain response,
as well as their instinctive ability to detect the site of the
Limitations to the study
In addition to the limitations stated above, the use of a
congenital block vertebra in the validation of motion palpation has its limitations. The number of suitable subjects
is restricted by the prevalence of the anomaly and the
absence of complicating factors such as spinal degeneration, instability and pain. Whereas previous motion palpation studies have used a
pair of examiners and 40 patients/subjects, due to the
scarcity of suitable patients with CBV, the number of
examiners had to be increased in order to have the same
inferential power. This posed the problem of subject comfort, since even the most gentle application of motion palpation technique repeated over 20 times is likely to cause
the subject discomfort. The use of so few patients also
makes it difficult to separate any clinically relevant results
from those attributable to the patient idiosyncrasies, and
is likely to induce greater change in the minor fixation
The results of this study indicate that even novice clinicians demonstrated the ability to correctly identify the
presence or absence of known cervical spine
intersegmental fixations by using specific motion palpation techniques on real patients with congenitally fused
vertebrae. These congenital blocked vertebrae represent a
true 'gold standard', allowing more accurate evaluation of
the validity of motion palpation. The results of this study
justify the clinical use of motion palpation in the diagnosis of true 'fixations' in the cervical spine. Competing interests
None declared. Authors' contributions
BKH and CP for formulation of research idea. BKH and
MD for research design, and data collection. BKH and CP
for manuscript preparation. All authors read and
approved the final manuscript. Acknowledgements
Anglo-European College of Chiropractic (AECC) for their assistance in the
use of their equipment, facilities and administrative support. Page 5 of 6
(page number not for citation purposes) BMC Musculoskeletal Disorders 2004, 5 Carol Churchill, Administrative Assistant, Canadian Memorial Chiropractic
College for typing the manuscript; and Bryan Groulx, Media Services,
CMCC for the photographic work. http://www.biomedcentral.com/1471-2474/5/19 24.
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