[
RESIDENT’S CASE PROBLEM
]
PAUL E. MINTKEN, PT, DPT1,2šB?I7C;JH?9A"PT, DPT²šJ?CEJ>O<BODD"PT, PhD3
Upper Cervical Ligament Testing
in a Patient With Os Odontoideum
Presenting With Headaches
P
hysical therapists play
an important role in the
screening of patients
with
cervical
spine
conditions.
Headaches
are
commonly treated by physical
therapists, 9,10,19,20,25, 35, 36, 38,48, 96
and a thorough differential
diagnosis is often needed to
determine if the headaches are
of musculoskeletal origin.56 The
lifetime prevalence of headache
(encompassing all headache
types) has been estimated to be
93% to 98%, and up to 17.8%
of individuals with headaches
meet the International Headache Society classification criteria for cervicogenic
headache.65 Physical therapy is often considered a first-line treatment for these
patients.10 Jull and colleagues36 have
demonstrated that a combined program
of cervical spine manipulative therapy
(thrust and nonthrust) and exercise can
reduce the symptoms of cervicogenic
headache. However, the risk of adverse
events following cervical spine thrust
manipulation is higher than for other re-
gions of the spine,6 and the role of
testing the integrity of the cervical
spine for potential contraindications to manual therapy is not
clearly defined.12,46,69
SUPPLEMENTAL
VIDEO ONLINE
TIJK:O:;I?=D0 Resident’s case problem.
T879A=HEKD:0 The role of premanipulative
testing of the cervical spine is an area of controversy, and there are very few data to inform and guide
practitioners on the use of ligamentous stability
tests when assessing the upper cervical spine.
T:?7=DEI?I0 A 23-year-old female was referred
to physical therapy by a neurologist for the
management of intractable headaches of possible
musculoskeletal origin. Her Neck Disability Index
score was 54% and she rated her headache pain as
varying from 3/10 to 9/10 on a numerical pain rating scale. She reported a 2-year history of intermittent lower extremity paresthesias without a known
mechanism or current symptoms. She was treated
in physical therapy for 11 visits with improvements
in cervical range of motion, strength, and intensity
of her headaches, but noted no change in the
frequency of headaches. She was subsequently
referred to the primary author for a second opinion
and potential manual therapy interventions. Initial
neurological screening examination for upper and
lower motor neuron lesions was unremarkable.
Assessment of the transverse ligament, using the
anterior shear test in supine, brought on paresthesias in both feet and her toes. The paresthesias
continued after the cessation of the test. The
Cervical instability has been
reported in patients with conditions commonly treated in physical therapy.13,17,36,41,62,80,89 The role
of premanipulative testing of the
Sharp-Purser test performed in sitting, immediately after the transverse ligament test, abolished
the paresthesias. She was then referred back to
her primary care physician for further evaluation.
Subsequent radiographs and magnetic resonance
imaging revealed that the patient had a C2-C3
Klippel-Feil congenital fusion and os odontoideum.
The patient was examined by a neurosurgeon who
concluded that she was not a surgical candidate.
Her neurological symptoms completely resolved,
but she continued to have headaches.
T:?I9KII?ED0 Os odontoideum is a clinically
important condition, given that the mobile dens
may render the transverse ligament incompetent,
leading to atlantoaxial instability. Both the role and
sequencing of upper cervical ligamentous testing
is controversial. The results of this case report suggest that physical therapists should be cognizant
of this condition and consider screening the upper
cervical ligaments prior to manual or mechanical
interventions to this region.
TB;L;BE<;L?:;D9;0 Diagnosis, level 4.
J Orthop Sports Phys Ther 2008;38(8):465-475.
doi:10.2519/jospt.2008.2747
TA;OMEH:I0 Klippel-Feil syndrome, manual
therapy, neck, transverse ligament, upper cervical
instability
1
Assistant Professor, University of Colorado at Denver and Health Sciences Center, School of Medicine, Department of Physical Therapy, Denver, CO; Fellow in the Regis University
Manual Therapy Fellowship, Regis University, Department of Physical Therapy, Denver, CO. 2 Physical Therapist, Wardenburg Health Center at the University of Colorado, Boulder,
CO. 3 Associate Professor and Manual Therapy Fellowship Coordinator, Regis University, School of Physical Therapy, Denver, CO. The individual in this case gave consent to use
her medical information and images as part of this publication. Address correspondence to Dr Paul Mintken, Education 2 South, Bldg L28, Room 3128, 13121 E 17th Avenue, PO
Box 6508, Aurora, CO 80045. E-mail: paul.mintken@uchsc.edu
journal of orthopaedic & sports physical therapy | volume 38 | number 8 | august 2008 | 465
[
RESIDENT ’ S CASE PROBLEM
<?=KH;'$Schematic illustration showing ligaments of the upper cervical spine seen from the posterior view.
Modified with permission from Barrow Neurological Institute, copyright 2008.
cervical spine is an area of controversy,
particularly in the area of vertebrobasilar
insufficiency.12,14,26,27,42-44,52,54,67,80 Additionally, there are very little data supporting or refuting the role of screening the
ligaments of the upper cervical spine to
determine the presence or absence of
instability.11,49,50,63,80,89 Cook et al13 stated
that clinical cervical spine instability
is difficult to diagnose, involves subtle
clinical features, and few valid, reliable
clinical tests exist to aid in differential
diagnosis. Numerous clinical tests for
cervical spine instability are currently in
use in clinical practice, and most are intended to assess the integrity of the alar
and transverse ligaments (<?=KH;'). Most
of these tests have not been validated in
patients with neck pain and headaches
and the level of reliability of the tests
varies.11,13,58,60 Uitvlugt and Indenbaum89
reported that the Sharp-Purser test was
moderately sensitive (88%) and highly
specific (96%) in detecting atlantoaxial
instability in individuals with rheumatoid
arthritis. Cattryse et al11 reported moderate to substantial interobserver reliability
(L = 0.50-1.0) for the upper cervical flexion test for 3 of 4 investigators and poor
to substantial interobserver reliability
(L = 0.0-0.67) with the lateral displacement test and the Sharp-Purser test when
performed on 11 children with Down’s
syndrome. The transverse ligament test
(also known as the anterior shear test)
is commonly taught in professional level
physical therapist programs; however, its
validity has not been established.63 Meadows50 argues that the above tests take
little time and should be done on every
patient with neck pain. However, Swinkels and Oostendorp,80 who have identified 5 upper cervical instability tests,
including a version of the anterior shear
test, argue that it is essential to determine
the reliability and validity of these tests to
determine their clinical usefulness.
Os odontoideum and Klippel-Feil
]
syndrome (KFS) can cause cervical instability. Os odontoideum is described
as a condition in which the dens is separated from the body of the axis.16 The incidence of os odontoideum is unknown;
but Sankar et al75 reported that 3.1% of
519 patients with abnormal cervical spine
radiographs had os odontoideum. KFS is
a congenital disorder characterized by
abnormal fusion of some of the cervical
vertebrae and the incidence has been
reported to range from 1 in 100 to 1 in
42 000 births.22,23,32 KFS has been associated with C1-C2 hypermobility and instability,7,66,71,76 as well as numerous other
organ system abnormalities.85
It is important for therapists to screen
patients for potential cervical instability
arising from traumatic, systemic, or congenital conditions. The purpose of this
case report is to describe the clinical examination, evaluation, and decision-making process involved in the management
of an individual presenting with chronic
headaches and signs and symptoms suggestive of upper cervical instability from
an underlying undiagnosed condition.
97I;:;I9H?FJ?ED
FWj_[dj>_ijeho
A
23-year-old female was referred to physical therapy with intractable headaches that were deemed
to be of possible musculoskeletal origin.
During the history intake, the patient
stated that she began having daily severe
right-sided headaches in October 2006
which she rated as 10/10 on a numerical pain rating scale (NPRS), where 0
represents no pain and 10 represents the
worst pain imaginable.31 Within a month,
she saw her primary care physician, who
treated her initially with Imitrex. This
offered some symptomatic relief but did
not change the frequency of her incapacitating headaches. A week after seeing her
primary care physician, she was referred
to a neurologist, who diagnosed her with
classic migraines with aura, with concomitant musculoskeletal headaches.2 The diagnosis of concomitant musculoskeletal
466 | august 2008 | volume 38 | number 8 | journal of orthopaedic & sports physical therapy
headaches was based on the presence of
a unilateral headache with paracervical
muscle hypertonicity and reproduction
of familiar headache symptoms with cervical muscle palpation.78 Amiri et al3 reported that it is common for patients to
present with 2 or more concurrent headache types but that, unfortunately, isolated features of physical impairment were
not helpful in differentiating cervicogenic
headaches. The neurologist prescribed a
low dose of Trazadone along with Midrin.
These medications had no effect on her
symptoms. No musculoskeletal imaging
was done at that time. The neurologist
referred the patient to physical therapy,
with the intent to seek magnetic resonance imaging (MRI) if the symptoms
did not improve.
At her initial physical therapy examination on November 14th, 2006, her Neck
Disability Index score was 54%, which
indicated severe disability.90 The patient
stated that her daily headache symptoms
ranged from 3/10 (best) to 9/10 (worst)
on the NPRS. Her headaches were typically worse at the end of the day and aggravated by stress and neck movements,
particularly extension. On her intake
form she reported a 2-year history of intermittent lower extremity paresthesias.
Upon further questioning she described
tingling sensations in her toes bilaterally
as well as the left foot through the ball
and dorsum of the foot. She had a recollection of the occurrence of these symptoms but could not recall any provoking
incidents or other associated symptoms
and denied current symptoms.
During her initial physical therapy
examination, further questioning about
her headaches revealed a history of migraines that began 2 years before, with
infrequent occurrence and lasting for up
to 2 days. She had been headache free for
9 months prior to the most recent onset
in October 2006 and stated that her typical symptoms would start with a visual
aura of colors and swirls lasting up to 2
hours. This was followed by a headache
that would begin in a focal point of pain
at the base of the skull/upper neck on the
right, which she characterized as “feeling
like a tent stake is being pounded into
my head.” These symptoms would dissipate somewhat with time to a generalized
right-sided headache, with a sensation of
intense pressure that was made worse
with stress and movement of the neck.
By the time she saw the neurologist in
November 2006, she was having daily intractable, incapacitating headaches that
would peak in the afternoon.
The initial physical therapy examination included screening for upper quarter (cervical and thoracic spine, shoulder,
elbow, wrist, and hand) range of motion
(ROM), myotomal strength, and deep
tendon reflexes deficits.50 The results of
the screen were considered unremarkable.
Further examination revealed moderate
limitations in cervical spine extension
and side bending, increased tone in the
upper trapezius and suboccipital muscles
bilaterally, tight pectoralis minors, weak
deep neck flexors and scapular retractors,
and a stiff upper thoracic spine. Sensory
testing and cranial nerve testing were not
performed but were reported as normal
in the examination performed 2 weeks
earlier by the neurologist. She was treated in physical therapy for 11 visits over a
period of 2 months. Treatments included
gentle soft tissue massage to the upper
trapezius and suboccipital musculature,
instruction in a home exercise program to
address postural strengthening of scapular retractors and deep neck flexors, and
stretches for the upper trapezius and
anterior chest wall musculature.48 She
made clinical improvements in strength,
cervical ROM, and the intensity of her
headaches, as her pain decreased to 1/10
to 2/10, but she continued to have daily
headaches. She was then (end of January
2007) referred to the primary author for
a second opinion and possible manual
therapy interventions.
CWdkWbF^oi_YWbJ^[hWf_ijÊi;nWc_dWj_ed
The history and the previous physical
therapist’s notes were reviewed. Additional questioning revealed that the headaches were daily and constant, she was
unable to find any interventions, medication or otherwise, that gave her relief. Her
Neck Disability Index that day was 44%,
indicating moderate disability. 90 She
stated that her headaches seemed to be
related to neck movements, particularly
looking up, and she reported feeling tired
all the time. When questioned regarding
the symptoms of fatigue, she stated that
she had always had trouble sleeping,
and this was exacerbated by her constant headaches. She did not relate any
other medical conditions that might be
contributing to feeling tired, and stated
that her general health was good except
for a history of a ruptured ovarian cyst.
A neurological screening examination,
which included deep tendon reflexes of
the upper and lower extremities, a myotomal screen, and tests for upper motor
neuron signs (Hoffman’s sign), was unremarkable.50 As she was not reporting
any recent or current sensory disturbances, a sensory examination was not
performed. On observation, the patient
presented with decreased kyphosis in the
mid thoracic spine, increased kyphosis at
the cervicothoracic junction, and forward
shoulders.39 No frontal plane postural deviations were noted. She rated her headache at the time of the evaluation at 2/10.
Cervical ROM was measured using a single inclinometer.30 Intraclass correlation
coefficients (ICCs) for interexaminer and
intraexaminer reliability of measuring
cervical ROM with a single inclinometer
has been reported to be 0.84 and 0.94 for
flexion and extension and 0.82 and 0.92
for side bending, respectively.30 The patient was asked to nod her head slowly
and bring her chin to her chest. Cervical
flexion measured 50° and did not reproduce any symptoms. Gentle overpressure in end range flexion did not cause
any change in her symptoms. Cervical
extension measured 40° and increased
her headache to a 4/10. When her symptoms increased with active ROM testing,
overpressure was not introduced. Upon
returning to an upright posture, the
headache returned to the baseline 2/10,
suggesting minimal irritability.47 Left side
journal of orthopaedic & sports physical therapy | volume 38 | number 8 | august 2008 | 467
[
TABLE
J[ij
RESIDENT ’ S CASE PROBLEM
]
Description of Upper Cervical
Ligamentous Testing 50,63
:[iYh_fj_ed
H[ikbj
Alar ligament stress
test (<?=KH;( and
EDB?D;L?:;E)
Patient is supine and the therapist grips and stabilizes the No excessive motion was
noted and the end feel
spinous process of the axis. The head and atlas are then
was capsular
side bent around the coronal axis of the atlantoaxial
joint. Ipsilateral rotation of the axis is prevented by the
stabilization of the axis. The end feel and the amount of
motion are assessed. If the alar ligament is intact, little
to no side bending can occur and the end feel should be
capsular. The test is then repeated with rotation of the
head and atlas on the axis and the end feel is assessed
Transverse ligament
test or anterior
shear test (<?=KH;
3 and EDB?D;
L?:;E)
Patient supine with the head supported by a pillow in the
Positive for bilateral lower
neutral position. The therapist supports the occiput in
extremity paresthesias
the palms of the hands and the third, fourth, and fifth
fingers while the 2 index fingers are placed in the space
between the occiput and the C2 spinous process, thus
overlying the neural arch of the atlas. The head and C1
are then lifted (sheared) anteriorly together, while the
head is maintained in its neutral position and gravity
fixes the rest of the neck. The patient is instructed to report any symptoms other than local pain and soreness.
The sensation of a lump in the throat or the presence of
cardinal signs or symptoms indicates a positive test50,63
Sharp-Purser test
(<?=KH;* and
EDB?D;L?:;E)
Relieved lower extremThe palm of one hand is placed on the patient’s forehead
ity paresthesias. No
and the spinous process of the axis is then gently fixed
excessive motion was
by a pinch grip of the thumb and fingertip pads of the
noted and no sense of
other hand. The head and neck are then gently flexed.
sliding or “clunking”
Through palmar pressure on the forehead, the occiput
was noted
and atlas are translated posteriorly. The unique feature
of this test is that the stress component is intended to
relieve the symptoms rather than aggravate them. It has
also been reported that a clunk may be noted as the
atlas reduces on the axis
bending was 50° and right side bending
42°, and symptoms did not increase at
end range with overpressure. Cervical rotation was measured using a goniometer.
Youdas et al95 reported that goniometric measurements of active ROM of the
cervical spine made by the same physical therapist had ICCs greater than 0.80.
Rotation to the right measured 82°, and
reproduced her headache at a 4/10 on the
NPRS. Her headache returned to 2/10
when she returned her head to midline.
Left rotation was 90° and symptoms did
not change with gentle overpressure.
The examination then focused on the
upper cervical spine, as it has been reported that the presence of painful upper
cervical joint dysfunction is a diagnostic
criterion for cervicogenic headache.4,34,37,78
The occipitoatlantal joints were assessed
in supine, as described by Greenman.24
The head/occiput is grasped by the physical therapist and passive upper cervical
flexion and extension, with the axis of
motion through the external auditory
meatus, was performed. Motion is then
assessed by introducing side bending/
translation, while maintaining end range
flexion or extension. As the upper cervical spine was flexed, the patient reported
moderate paresthesias into her toes bilaterally. Upon release of upper cervical flexion, the symptoms disappeared.
These symptoms have been described as
cardinal symptoms of upper cervical instability11 and cervical cord compession.63
Pettman63 defined “cardinal symptoms”
as any of the following signs or symptoms
<?=KH;($Alar ligament stress testing. Spinous
process of the axis is stabilized while the head
and the atlas are side bent or rotated to assess for
excessive movement. (A) Start position; (B) sidebending stress; (C) rotation stress.
that are reproduced by active or passive
movements of the head or neck: an overt
loss of balance (drop attacks), facial or
lip paresthesias, bilateral or quadrilateral limb paresthesias, or nystagmus. Upper cervical instability was suspected, so
craniovertebral ligamentous stress tests
were performed (TABLE 1). As the patient
was already supine and did not have any
symptoms, the alar ligament stress tests
were performed as described by Pettman
(<?=KH; ( and EDB?D; L?:;E).63 A normal
capsular end feel was appreciated with
no excessive movement, and these tests
were not painful and did not reproduce
any paresthesias. As the patient continued to be symptom free, the transverse
468 | august 2008 | volume 38 | number 8 | journal of orthopaedic & sports physical therapy
<?=KH;)$Transverse ligament or anterior shear test.
The therapist supports the occiput, while the 2 index
fingers are placed in the space between the occiput
and the C2 spinous process. The head and C1 are
then moved anteriorly as a unit on the cervical spine.
(A) Start position; (B) end position.
<?=KH;+$Lateral radiograph. Arrow points to Klippel-Feil fusion at C2-C3. The parallel lines outline the anterior
atlantodental interval (AADI). No increased motion is noted in the AADI in neutral, flexion, or extension. The
measurement landmarks for the AADI are the posterior surface of the anterior tubercle of C1 and the anterior
surface of the odontoid.95
<?=KH;*$Sharp-Purser test. The palm of one hand
is placed on the patient’s forehead while the spinous
process of the axis is held by a pinch grip of the
opposite hand. Then the head and neck are the gently
flexed. Through palmar pressure on the forehead, the
occiput and atlas are translated posteriorly.
ligament was assessed using the anterior
shear test as described by Meadows (<?=KH;) and EDB?D;L?:;E)50: “The patient lies
supine with the head supported by a pillow in the neutral position. The therapist
supports the occiput in the palms of the
hands and the third, fourth, and fifth fingers, while the 2 index fingers are placed
in the space between the occiput and the
C2 spinous process, thus overlying the
neural arch of the atlas (C1). The head
and C1 are then translated anteriorly as
a unit with the head maintained in its
neutral position while gravity maintains
the remainder of the cervical spine/neck
against the table. The patient is instructed to report any symptoms other than local pain and soreness.” In this case, the
patient reported the return of moderate
paresthesias into her toes, which continued after the cessation of the test. She
was then carefully assisted to a sitting
position and the Sharp-Purser test (<?=KH;* and EDB?D; L?:;E), as described by
Pettman,63 was performed, which abolished the paresthesias. No “clunk” was
noted with the test and there was no
perceived excessive motion. Upon re-
lease of the force applied during the test
the patient had a return of paresthesia in
1 lower extremity that she described as
very mild and similar to the symptoms
she had described during the intake history. Pettman63 stated that the reduction
of symptoms with the Sharp-Purser test
is suggestive of upper cervical instability.
An assessment of the deep tendon reflexes of the lower extremities was repeated
and deemed normal.
The patient was scheduled to see her
primary care physician in the same building approximately 90 minutes after her
physical therapy appointment that day,
and a message was left for her physician
explaining the concerns of upper cervical instability. She saw her physician later
that day but no information regarding
journal of orthopaedic & sports physical therapy | volume 38 | number 8 | august 2008 | 469
[
RESIDENT ’ S CASE PROBLEM
]
physical examination was recorded in the
physician’s note.
:_W]deij_Y?cW]_d]
The primary care physician referred the
patient for diagnostic imaging, including flexion/extension radiographs of the
cervical spine. Radiographs revealed that
the patient had a type I C2-C3 KlippelFeil congenital fusion74 (<?=KH;I+#.). Samartzis et al74 define a type I Klippel-Feil
as a single congenitally fused cervical
segment. During the 6 days following
the physical therapy examination and
the physician’s visit, the patient stated
that her toes tingled while lying in supine
or when she brought her head into cervical flexion. She also reported intermittent dizziness, ataxia, and 2 episodes of
falling down. Based on the results of the
radiographs and the neurological symptoms, the patient underwent MRI of the
cervical spine 6 days after the physical
therapy examination. An os odontoideum
was identified on a sagittal image of the
MRI (<?=KH;I/ and 10). Os odontoideum
describes a condition in which a portion
of the odontoid process is separated from
the body of the axis,51 potentially rendering the transverse ligament unable to stabilize the atlas on the axis.18,73
The imaging was subsequently interpreted by 3 radiologists, who all
concurred that the imaging most likely
represented an os odontoideum. The anterior atlantodental interval (AADI)94 was
deemed to be normal on the radiographs
(<?=KH;I+#-), but this could be a result of
muscle guarding. On the MRI (<?=KH;I
/ and 10), the dens fragment appears to
have sclerotic margins, suggesting a longstanding entity. This is supported by the
lack of edema on the sagittal T2 MRI (<?=KH;'&). One radiologist commented that
the os odontoideum was larger and less
irregular than a typical case, and that it
involved a larger amount of the dens than
is typically seen. This could explain the
instability under stress, as the transverse
ligament and alar ligaments may stabilize
the os fragment and pull it anteriorly with
C1 during the anterior shear test, with re-
<?=KH;,$Flexion radiograph. Arrow points to
Klippel-Feil fusion at C2-C3. The parallel lines
outline the anterior atlantodental interval (AADI). No
atlantoaxial subluxation was noted.
sultant motion occurring between the os
fragment and the C2 vertebra. This could
be confirmed with axial or coronal MRI
through the foramen magnum (which
were not performed in this case). Also
noted was a synchondrosis of the base of
the dens with the body of C2 and partial
fusion of C2 with the underlying C3. No
cord signal changes were noted, but an
area of narrowing was identified that was
probably long-standing (<?=KH;'&).
The patient was referred to a neurosurgeon 9 days after the physical therapy
examination, who completed a thorough
neurological examination, including sensation, strength testing, cranial nerve
examination, and testing for both upper
and lower motor neuron problems. The
examination was deemed unremarkable.
Cervical spine ROM was not assessed.
The neurosurgeon told the patient that
both os odontoideum and KPS are congenital conditions that do not warrant
surgical intervention in the absence of
progressing neurological symptoms. Her
symptoms of lower extremity paresthesias had resolved within 7 days, and she
was no longer reporting dizziness, ataxia,
or falling down. She continued to have
daily incapacitating headaches and she
subsequently withdrew from the univer-
<?=KH;-$Extension radiograph. Arrow points
to Klippel-Feil fusion at C2-C3. The parallel lines
outline the anterior atlantodental interval (AADI). No
atlantoaxial subluxation was noted.
<?=KH;.$Open-mouth view. No abnormalities were
noted.
sity and no longer had health insurance.
The patient was contacted 6 months
later, and she continued to have headaches but did not report having had any
neurological signs or symptoms during
that time.
:?I9KII?ED
T
he prevalence of upper cervical
instability is unknown, as it may be
present in asymptomatic individuals.28 KFS, characterized by congenital
fusion of 2 or more cervical vertebrae, is
present in up to 1% of the population and
has been associated with craniocervical
abnormalities that can lead to spontaneous and progressive neurological sequelae after relatively minor neck trauma.23,79
470 | august 2008 | volume 38 | number 8 | journal of orthopaedic & sports physical therapy
<?=KH;/$Sagittal T1-weighted magnetic resonance image. Arrows point to area of os odontoideum and KlippelFeil fusion of C2-C3.
KFS has also been associated with genitourinary tract abnormalities (65%),53
scoliosis (60%),82,84,93 facial asymmetries and torticollis (45%),84 hearing loss
(38%),85 Sprengel’s deformity (36%),84
spinal cord abnormalities (syringomyelia
15%),88 spina bifida,59 cervical stenosis,68
cleft palate,85 congenital upper extremity
abnormalities,83 cervical ribs,87 and cardiovascular anomalies.61
The prevalence of os odontoideum
is unknown.86 Os odontoideum was
initially thought to be due to a congenital failure of fusion of the dens to the
remainder of the axis.29 Sankar et al75
reported that 2 separate etiologies may
explain os odontoideum: posttraumatic
and congenital. Verska et al91 reported
on a set of identical twins in which 1
twin presented with an os odontoideum
after trauma and the other twin had a
normal cervical spine and no history of
trauma. Crockard and Stevens15 state
that os odontoideum may be the product of excessive movement at the time
of ossification of the cartilaginous dens,
and that the presentation is similar to
an unfused Type II odontoid fracture.
In this case, the Klippel-Feil fusion
at C2-C3 may have lead to excessive motion at C1-C2 resulting in an os odontoideum. Several authors have reported
that os odontoideum often accompanies
Klippel-Feil fusions, particularly when
present at C2-C3,7,55,76 and Morgan et al55
suggested there may be a pattern of autosomal dominant familial inheritance
for this combination. Os odontoideum
is clinically important because an insufficient dens may render the transverse
ligament incapable of restraining the
atlas on the axis.18,73 With increased motion, upper cervical cord or vertebral artery impingement may occur.33,40,51,72,77,81,92
Michaels et al51 reported on a 35-year-old
taxi driver who was involved in a lowspeed head-on motor vehicle collision
who died 4 days later. Autopsy revealed
an os odontoideum that had compressed
the spinal cord on flexion of the head.
Sherk and Dawoud76 report a case of an
individual with os odontoideum with
KFS who developed quadriplegia and ultimately died after falling and hitting his
head. Although Galli et al21 reported on a
patient with os odontoideum presenting
with cervical vertigo, the role of os odontoideum and upper cervical instability in
headaches and other cervical complaints
is unclear.
Upper cervical spine instability can be
a benign condition that goes unnoticed
for years. Nagashima et al57 report the
case of a 42-year-old woman presenting
with KFS and severe hypermobility of
the upper cervical spine that showed no
signs of neurological involvement. Morgan et al55 reported on an asymptomatic
16-year-old boy with familial os odontoideum and a Klippel-Feil fusion of C2-C3.
While upper cervical instability can and
does exist in asymptomatic individuals, it
journal of orthopaedic & sports physical therapy | volume 38 | number 8 | august 2008 | 471
[
RESIDENT ’ S CASE PROBLEM
<?=KH;'&$Sagittal T2-weighted magnetic resonance image. The left arrow points to the area of os odontoideum.
The dens fragment appears to have sclerotic margins with no evidence of edema, indicating a long-standing entity.
The black arrow points to a potential area of narrowing of the cervical spinal cord.
can lead to serious neurological sequelae
in others. Pizzutillo et al64 suggest that
individuals with KFS with hypermobility
of the upper cervical segment are at risk
for neurologic sequelae.
The role of screening the upper cervical spine is an area of controversy,
particularly in regard to the vertebral
artery.1,8,46,49,69,70 The role of craniocervical ligamentous testing in screening for
cervical instability has received much less
attention. Numerous clinical tests have
been developed to assess the stability of
the upper cervical spine.11,13,49,50,63,89 Un-
fortunately, no consensus exists regarding
which tests, if any, are appropriate, and
there is no clear guidance on an appropriate sequence to testing the ligamentous
structures of the upper cervical spine. In
a study investigating the reliability of 3
commonly used tests for upper cervical
instability in children with Down’s syndrome, the sequence of the testing was
chosen at random.11
In retrospect, the sequencing of the
upper cervical ligament testing in this
case may not have been ideal. In our subsequent literature review, the author of 1
]
article described a “reasoned” approach
to assessing upper cervical ligamentous
stability. Aspinall5 suggests that if upper cervical instability is suspected, the
Sharp-Purser test should be performed
first before any of the other ligamentous
tests. If, and only if, the Sharp-Purser is
negative, Aspinall then suggests that, in
the absence of neurological symptoms,
a test that passively moves the atlas on
the axis be used to assess for laxity of the
transverse ligament. In this case, it would
have potentially been safer to perform the
Sharp-Purser first, which is considered a
relocation or “alleviation” test, to assess
for instability. The Sharp-Purser test is
not without controversy, as Pettman63
stated that this test is intended to relieve
neurological symptoms, while Meadows49
called the use of the Sharp-Purser in the
presence of neurological symptoms an
“exercise in futility and risk.”
In this particular case, it is the authors’
opinion that the Sharp-Purser would
have been negative if performed first, as
the results of the test that was ultimately
performed did not reveal excessive motion and the patient had no symptoms to
be relieved prior to the application of the
anterior shear test. The positive finding
of the Sharp-Purser performed in this
case was the relief of paresthesia, which
was elicited by the initial application of
the anterior shear test. Had the SharpPurser test been performed first, it would
have been considered negative (no perception of instability or symptoms to be
relieved), leading to the performance of
the anterior shear test and likely the same
results. While the sequencing of the examination was possibly less than optimal,
it is the authors’ opinion that it required
a provocation of the symptoms for the
clinical exam to suggest the presence of
upper cervical instability in this patient.
The anterior shear test should be viewed
as a provocative test, one in which cardinal signs may be elicited in an unstable
upper cervical spine. While this is clearly
an area that requires more research, the
findings in this case report combined
with previously published expert opinions
472 | august 2008 | volume 38 | number 8 | journal of orthopaedic & sports physical therapy
suggest that, in the presence of cardinal
signs or symptoms, the Sharp-Purser test,
which is aimed at alleviating symptoms,
should be performed first. In the absence
of symptoms, tests designed to alleviate
symptoms should still be performed first
in an attempt to identify excessive mobility. This should be followed by provocative
tests only if no symptoms were produced
and no excessive mobility is perceived.
Provocative tests are not recommended
in the presence of symptoms, suggesting
neurological compromise.
It could also be argued that the patient should have been sent back to the
physician following the onset of bilateral
lower extremity paresthesias with passive
upper cervical flexion, as this motion has
been described as a test to identify upper
cervical instability.11 Indeed, the primary
author had previously referred patients
back to physicians based on the suspicion
of upper cervical instability based on the
results of the clinical examination, only to
be accused of what Pettman63 refers to as
“craniovertebral hysteria.” The timing, necessity, and threshold for medical referral
is unclear. In a previously published case
report involving suspected upper cervical
instability (no imaging was ever taken), a
Sharp-Purser test was performed in which
a “large amount of movement was appreciated” and the patient had a reduction in
her right-sided face, ear, neck, and shoulder pain.45 Despite these findings, and a
history of dizziness and bilateral blurred
vision, the patient was not referred back
to the physician for further examination.
The patient was diagnosed with clinical
instability of the cervical spine and subsequently treated successfully with manual
therapy. One could argue that this patient
should have been referred for further diagnostic workup.
Despite the relative rarity of os odontoideum and the controversy surrounding clinical testing of upper cervical
instability, failure of a physical therapist
to recognize this condition could result in
severe patient injury when manual physical therapy procedures or end range mobility exercises are performed. We have
described a case where the physical therapist examination of the upper cervical
spine was highly suggestive of a potentially serious condition that required further medical referral. Even with limited
information on the diagnostic utility of
the physical examination tests to determine the presence or absence of cervical spine instability, and the sequence in
which they should be performed, it is our
opinion that in this patient the results of
these tests represented an absolute contraindication to any further examination or treatment to the cervical region
until further diagnostic workup was
performed.
*$
+$
,$
-$
.$
9ED9BKI?ED
/$
E
s odontoideum is a clinically
important condition given that the
mobile dens may render the transverse ligament incompetent, leading to
atlantoaxial instability. This can have potentially devastating consequences to the
spinal cord or vertebral arteries.33,40,51,72,76,
77,81,92
The results of this case report suggest that physical therapists should be
cognizant of this condition and consider
screening the upper cervical spine prior
to manual or mechanical interventions
to this region. At this time no consensus exists regarding which tests, if any,
are appropriate, and there is no clear
guidance on an appropriate sequence
to testing the ligamentous structures of
the upper cervical spine. Clearly, further research and dialogue are needed
in this area. T
10.
11.
12.
13.
'*$
'+$
H;<;H;D9;I
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@
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