Degenerative Disorders of the Cervical Spine Massimo Leonardi, Norbert Boos Core Messages ✔Age-related changes of the cervical spine can lead to cervical spondylosis, disc herniation and
Trang 1major reduction in the undesirable sequelae of surgical injury with improved recovery and reduction in postoperative morbidity and overall costs.
Blumenthal S, Min K, Nadig M, Borgeat A ( 2005) Double epidural catheter with ropiva-caine versus intravenous morphine: a comparison for postoperative analgesia after sco-liosis correction surgery Anesthesiology 102:175–180
In this prospective study, following scoliosis correction surgery, continuous epidural local anesthetics administered through two epidural catheters have been shown not only
to provide better postoperative analgesia compared to intravenous morphine, but also to reduce side effects, improve bowel function and increase patient satisfaction.
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2 Blumenthal S, Min K, Nadig M, Borgeat A (2005) Double epidural catheter with ropivacaine versus intravenous morphine: a comparison for postoperative analgesia after scoliosis cor-rection operation Anesthesiology 102:175 – 180
3 Blumenthal S, Borgeat A, Nadig M, Min K (2006) Postoperative analgesia after anterior cor-rection of thoracic scoliosis: a prospective randomized study comparing continuous double epidural catheter technique with intravenous morphine Spine 31:1646 – 51
4 Blumenthal S, Min K, Marquardt M, Borgeat A (2007) Postoperative intravenous morphine consumption, pain scores, and side effects with perioperative oral controlled-release oxyco-done after lumbar disectomy Anesth Analg 105:233 – 7
5 Boezaart AP, Eksteen JA, Spuy GV, Rossouw P, Knipe M (1999) Intrathecal morphine Dou-ble-blind evaluation of optimal dosage for analgesia after major lumbar spinal surgery Spine 24:1131 – 7
6 Carli F (1999) Perioperative factors influencing surgical morbidity: what the anesthesiolo-gists need to know Can J Anesth 46:R70 – 79
7 Dearborn JT, Hu SS, Tribus CB, Bradford DS (1999) Thromboembolic complications after major thoracolumbar spine surgery Spine 24:1471 – 6
8 Ebraheim NA, Lu J, Yang H, Heck BE, Yeasting RA (2000) Vulnerability of the sympathetic trunk during the anterior approach to the lower cervical spine Spine 25:1603 – 6
9 Fang A, Hu SS, Endres N, Bradford DS (2005) Risk factors for infection after spinal surgery Spine 30:1460 – 5
10 Fujibayashi S, Shikata J, Yoshitomi H, Tanaka C, Nakamura K, Nakamura T (2001) Bilateral phrenic nerve palsy as a complication of anterior decompression and fusion for cervical ossification of the posterior longitudinal ligament Spine 26:E281 – 6
11 Furnary AP, Zerr KJ, Grunkemeier GL, Starr A (1999) Continuous intravenous insulin infu-sion reduces the incidence of deep sternal wound infection in diabetic patients after cardiac surgical procedures Ann Thorac Surg 67:352 – 60
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16 Kehlet H (1994) Postoperative pain relief – what is the issue? Br J Anaesth 72:375 – 8
17 Kehlet H (1997) Multimodal approach to control postoperative pathophysiology and reha-bilitation Br J Anaesth 78:606 – 17
18 Kehlet H (2000) Manipulation of the metabolic response in clinical practice World J Surg 24:690 – 5
19 Kurz LT, Garfin SR, Booth RE, Jr (1989) Harvesting autogenous iliac bone grafts A review
of complications and techniques Spine 14:1324 – 31
20 Mineiro J, Weinstein SL (1997) Delayed postoperative paraparesis in scoliosis surgery A case report Spine 22:1668 – 72
21 Reuben SS, Connelly NR (2000) Postoperative analgesic effects of celecoxib or rofecoxib after spinal fusion surgery Anesth Analg 91:1221 – 5
22 Roderick P, Ferris G, Wilson K, Halls H, Jackson D, Collins R, Baigent C (2005) Towards
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Postoperative Care and Pain Management Chapter 16 425
Trang 3Degenerative Disorders of the Cervical Spine
Massimo Leonardi, Norbert Boos
Core Messages
✔Age-related changes of the cervical spine can
lead to cervical spondylosis, disc herniation and
spondylotic radiculopathy/myelopathy
✔Neck pain often lacks a clear morphological
correlate (i.e is non-specific)
✔Cervical spondylosis more frequently causes
radiculopathy than disc herniation and
pre-dominantly affects C5/6 and C6/7
✔Mechanical compression and inflammatory
changes cause the clinical syndrome of
radicu-lopathy
✔Cervical spondylotic myelopathy is caused by
static (spinal canal stenosis), dynamic
(instabil-ity), vascular and cellular (cell injuries,
apopto-sis) factors
✔The cardinal symptom of cervical radiculopathy
is radicular pain with or without a sensorimotor
deficit
✔Early symptoms of cervical myelopathy are
“numb, clumsy, painful hands” and disturbance
of fine motor skills Late symptoms comprise
atrophy of the interosseous muscles, gait
dis-turbance, ataxia and symptoms of progressive
tetraparesis
✔The diagnostic accuracy of functional
radio-graphs to reliably identify segmental instability
is low Instability remains a clinical diagnosis
✔MRI is the imaging modality of choice for
quan-tifying the extent of degenerative alterations
and spinal cord compression
✔CT myelography favorably demonstrates spurs,
ossifications and foraminal stenosis in relation
to the neural structures
✔Neurophysiological studies are helpful in
diag-nosing subclinical myelopathy and
differentiat-ing radiculopathy from peripheral neuropathy
✔The natural history of radiculopathy is benign while the spontaneous course of myelopathy is characterized either by long periods of stable disability followed by episodes of deterioration
or a linear progressive course
✔Scientific evidence for treatment guidelines of degenerative cervical disorders is poor
✔Neck pain is treated non-operatively in the vast majority of patients Indications for surgery are rare
✔Cervical radiculopathy frequently responds favorably to conservative care Surgery is indi-cated in patients with persistent symptoms or progressive neurological deficits
✔The gold standard of treatment of radiculopa-thy is anterior discectomy and fusion, resulting
in a favorable outcome in 80 – 90 % of patients
✔Alternative methods (i.e additional anterior plate fixation, cage fusions, total disc arthropla-sty, or minimally invasive decompressions with-out fusion) have not been shown to result in a superior outcome
✔Mild cervical myelopathy without progression can be treated conservatively Surgery is indi-cated in moderate to severe myelopathy Com-plete recovery of advanced myelopathy is rare and early surgery is therefore indicated
✔The principal aim of surgery for cervical spon-dylotic myelopathy is the decompression of the spinal cord The surgical techniques include multilevel discectomies or corpectomies with
or without instrumented fusion, laminectomy with or without instrumented fusion or lamino-plasty
✔The choice of technique is dependent on the target pathology and patient characteristics
Trang 4a b
c
d
Case Introduction
A 28-year-old female suffered from neck and arm pain for
3 weeks without neurological deficits She was referred for
physical therapy and manipulation At the fourth session,
the patient felt an excruciating sharp pain in her neck
subse-quent to a manipulation She was unable to stand and
developed a rapidly progressive tetraparesis sub C6 The
patient was referred for emergency diagnosis and
treat-ment A lateral radiograph (a) did not show any evidence for
a fracture/dislocation MRI revealed a massive disc
hernia-tion (arrow) with severe spinal cord compression
(arrow-heads) at the level of C6/7 (b,c) Immediate spinal cord
decompression was prompted by anterior cervical
discec-tomy, sequestrectomy and fusion (Robinson-Smith
tech-nique) (d) The patient improved rapidly after the surgery At
1-year follow, the patient had full neurological recovery and
was symptom-free.
Epidemiology Degenerative alterations of the cervical spine are usually referred to as cervical spondylosis This entity represents a mixed group of pathologies involving the
intervertebral discs, vertebrae, and/or associated joints and can be due to aging (“wear and tear”, degeneration) or secondary to trauma The predominant clini-cal symptom is neck pain, which is often associated with shoulder pain The degenerative alterations can lead to a central or foraminal stenosis compromising nerve roots or spinal cord (Fig 1 ) These pathologies are termed cervical spondy-lotic radiculopathy (CSR) and cervical spondyspondy-lotic myelopathy (CSM),
respec-tively CSR should be differentiated from disc herniation related radiculopathy
The annual incidence of
neck pain is about 15 %
In a Dutch national survey, there was an incidence of 23.1 per 1 000
person-years for neck pain and 19.0 per 1 000 person-person-years for shoulder symptoms [38].
Dutch general practitioners were consulted approximately seven times each week for a complaint relating to the neck or upper extremity; of these, three were new complaints or new episodes [38] The annual incidence of neck pain was 14.6 % in
a cohort of 1 100 randomly selected Saskatchewan adults, 0.6 % of whom devel-oped disabling neck pain [66] Women were more likely to develop neck pain
Trang 5a b
Figure 1 Cervical spondylosis
a, bAge-related changes can lead to disc herniations, cervical spondylosis, osteophyte formations, facet joint
osteoar-thritis, and compromise of the exiting nerve roots and the spinal cord.
than men [66] In a Swedish survey on 4 415 subjects, a prevalence rate of 17 % for
neck pain was found Fifty-one percent of the neck pain subjects also had chronic
low back pain [108] A history of a neck injury was reported by 25 % of patients
with neck pain [108] In a prospective longitudinal investigation in France, the
prevalence and incidence rates of neck and shoulder pain were assessed in an
Neck pain is often associated with shoulder pain and LBP
occupational setting [48] The authors found that the prevalence (men 7.8 %,
women 14.8 % in 1990) and incidence (men 7.3 %, women 12.5 % for the period
1990 – 1995) of chronic neck and shoulder pain increased with age, and were
higher among women than men in every birth cohort examined The
disappear-ance rate of chronic neck and shoulder pain decreased with age The paper
high-lighted that adverse working conditions (e.g repetitive work under time
con-straints, awkward work for men, repetitive work for women) contributed to the
development of neck and shoulder pain, independently of age [48]
The most frequent radiculopathy is C6 and C7
Cervical radiculopathy is much less frequent than neck and shoulder pain with
a prevalence of 3.3 cases per 1 000 people The peak annual incidence is 2.1 cases
per 1 000 and it occurs in the 4th and 5th decades of life [278] In a Sicilian
popula-tion of 7 653 subjects [237], a prevalence of 3.5 cases per 1 000 was found for
cervi-cal spondylotic radiculopathy, which increased to a peak at age 50 – 59 years, and
decreased thereafter The age-specific prevalence was consistently higher in
women [237] An epidemiological survey of cervical radiculopathy at the Mayo
Clinic in Rochester [222] revealed that the average annual age-adjusted incidence
rate per 100 000 population for cervical radiculopathy was 83.2 (107.3 for males,
63.5 for females) The age-specific annual incidence rate per 100 000 population
reached a peak of 202.9 for the age group 50 – 54 years A history of physical
exer-tion or trauma preceding the onset of symptoms occurred in only 14.8 % of cases
The median duration of symptoms prior to diagnosis was 15 days A
mono-radi-culopathy involving C7 nerve root was most frequent, followed by C6
The most frequent cause
of cervical radiculopathy
is spondylosis
A confirmed disc protrusion was responsible for cervical radiculopathy in
21.9 % of patients; in 68.4 % it was related to spondylosis During the median
duration of follow-up of 4.9 years, recurrence of the condition occurred in 31.7 %,
Degenerative Disorders of the Cervical Spine Chapter 17 431
Trang 6and 26 % underwent surgery for cervical radiculopathy At last follow-up, 90 % of patients were asymptomatic or only mildly incapacitated due to cervical radicu-lopathy [222]
OPLL is a frequent cause
of cervical myelopathy
in Asians
The epidemiology data of cervical spondylotic myelopathy have not been well
explored The aging process results in degenerative changes of the cervical spine that, in advanced stages, can cause compression of the spinal cord It is the most common cause of spinal cord dysfunction in the elderly [300] A special form of cervical myelopathy is caused by the ossification of the posterior longitudinal
lig-ament (OPLL) It is a multifactorial disease in which complex genetic and
envi-ronmental factors interact This disease is especially found in the Asian popula-tion [134] In the Japanese populapopula-tion, the reported prevalence rate ranges from 1.8 % to 4.1 % [169, 196, 254] The prevalence rate of OPLL in the cervical spine was significantly lower in the Chinese (0.2 %) and Taiwanese populations (0.4 %) [169] A radiographic evaluation of cervical spine films at the Rizzoli Orthopae-dic Institute in Bologna, Italy, revealed a prevalence of 1.83 % with a peak in the
45 – 64 year age group (2.83 %) This prevalence was much higher than that so far reported in Caucasians [266]
Pathogenesis
Age-related changes
are only weakly correlated
with symptoms
Age-related changes of the intervertebral disc initiate the degenerative cascade and lead to a progressive deterioration of the motion segment (see Chapter 4) The disc height decreases leading to disc bulging as a result of progressive changes to the extracellular matrix of the disc Microinstability results in reactive hyperostosis with formation of osteophytes at the vertebral endplates which can penetrate into the spinal canal and compromise the spinal cord and nerve roots (Fig 1 ) Osteophytes of the uncovertebral and facet joints reduce the mobility of the segment Segmental instability leads to a hypertrophy of the yellow ligament
and causes a narrowing of the spinal canal and foramen During later stages of
segmental degeneration, kyphosis of the cervical spine can occur and further
compromise the spinal cord and nerve roots [250] Although cervical spondylo-sis can lead to symptoms such as neck pain, CSR and CSM, we should bear in mind that the vast majority of changes are asymptomatic [29]
Neck Pain
A morphological correlate
is rarely found for neck pain
The most common causes of subaxial neck pain are muscular and ligamentous factors related to improper posture, poor ergonomics and muscle fatigue [223] The intervertebral disc and facet joints are richly innervated [51, 81, 176] Degen-erative alterations can therefore lead to pain generation (see Chapters 4, 5) representing a specific cause of neck pain In the vast majority of cases, however,
no structural correlate can be found to explain axial neck pain, i.e neck pain
most often is non-specific.
Cervical Disc Herniation
Disc extrusions and sequestrations tend
to resorb with time
Cervical radiculopathy due to disc herniation usually occurs during early stages
of motion segment degeneration and mainly affects individuals in the 4th and 5th decades of life [222] The main causes of disc herniation are age-related changes of the intervertebral disc making the anulus fibrosus susceptible to fis-suring and tearing (see Chapter 4 ) The so-called “soft herniation” exhibits a
chance for spontaneous resorption particularly in cases with disc extrusion and sequestration Vascular supply probably plays a role in the mechanism of
Trang 7tion [177] The phase and position of the extrusion were identified as significant
factors affecting cervical disc herniation resorption [177]
Spondylotic radiculopathy
is caused by mechanical and inflammatory factors
The pathophysiology of radiculopathy involves both mechanical deformation
and chemical irritation of the nerve roots [232] The release of proinflammatory
cytokines and nerve growth factor (NGF) was recently identified to play a major
role in the development of radicular arm pain [272] Our current understanding
of the pathogenesis of disc herniation related radiculopathy is mainly based on
studies of the lumbar spine We therefore prefer to provide a detailed overview of
this issue in Chapter 18
Cervical Spondylotic Radiculopathy
Mechanical nerve root compromise is not closely related to symptoms
Spondylotic radiculopathy develops during later stages of motion segment
degeneration and is caused by osteophytes of the endplates, facet and
uncoverte-bral joints narrowing the spinal canal and neuroforamen (Fig 1) These radicular
entrapments (often referred to as “hard herniations”) do not spontaneously
improve and usually exhibit a slowly progressing deterioration Humphreys et al
[130] showed that in symptomatic patients foraminal heights, widths and areas
are smaller than in asymptomatic controls Foraminal stenosis can cause
perma-nent or intermittent mechanical irritation of the nerve roots and can lead to
hyp-oxia of the nerve root and dorsal root ganglion The subsequent release of
proin-flammatory cytokines and NGF is responsible for the generation of radicular
pain [272] Spontaneous resolution of these inflammatory processes can occur
and explain why some patients can have long asymptomatic periods This is
sup-ported by the finding that the incidence of radiculopathy does not closely
corre-late with age although there is an age-recorre-lated increase of radiological alterations
[278]
Cervical Spondylotic Myelopathy
Cervical spondylosis
is the most frequent cause
of myelopathy in Caucasians
In contrast to the lumbar spine, obliteration of the spinal canal by a disc
hernia-tion or osseous spurs can lead to severe neurological deficits because of a direct
compromise of the spinal cord resulting in the clinical syndrome of myelopathy.
Myelopathy can result from (Table 1):
Table 1 Etiology of cervical myelopathy
) large disc herniation ) cervical spondylosis
) traumatized narrow spinal canal ) ossified posterior longitudinal ligament (OPLL)
CSM generally can cause a variety of neurological disturbances like spastic gait,
ataxia, hyperreflexia, sensory impairment, sphincter disturbances, and motor
deficit The degree and combination of each symptom can vary extensively and
there is no close relationship between the extent of compression and clinical
symptoms The pathophysiology of CSM involves [16, 32, 80]:
) static factors
) dynamic factors
) biologic and molecular factors
Static Factors
A narrow spinal canal predisposes to CSM
The normal sagittal diameter of the spinal canal (C3 – 7) is 14 – 22 mm [44, 74,
119, 207] with enough space for the neural elements, ligaments and epidural fat
Degenerative Disorders of the Cervical Spine Chapter 17 433
Trang 8The spinal cord occupies about three-quarters of the size of the spinal canal in
the subaxial spine [80] A narrowing of the spinal canal size can result from disc
degeneration, vertebral osseous spurs, osteophyte formation at the level of the facet joints, and yellow ligament hypertrophy, calcification or ossification [205]
Patients with a congenitally narrow spinal canal (< 13 mm) have a higher risk
for the development of symptomatic cervical myelopathy [9, 74] Penning et al [209] showed that concentric compression of the cord resulted in long tract signs only after the cross-sectional area of the cord had been reduced by about 30 % to
a value of about 60 mm2or less This is in line with findings by Teresi et al [267], who reported that spinal cord compression was observed in seven of 100 asymp-tomatic patients The percentage of cord area reduction never exceeded 16 % and averaged approximately 7 % Ogino et al [194] found that the degree of cord compromise was in good correlation with the ratio of the anteroposterior diam-eter to the transverse diamdiam-eter, designated as an anteroposterior compression ratio
Dynamic Factors
Instability and kyphosis
aggravate CSM
Dynamic compression appears to play a major role in CSM Flexion of the
cervi-cal spine causes a lengthening of the spinal cord which can be stretched over pos-terior vertebral spondylosis In an already narrow canal this motion may damage anterior spinal cord structures [80] Extension of the cervical spine provokes a buckling of the ligamentum flavum with dorsal compression of the spinal cord combined with anterior compression due to posterior disc bulging and/or
verte-bral body osteophytes [80] This results in a pincer effect that places the neurons
of the spinal cord at great risk [40, 201, 205] Advanced disc degeneration and height loss may allow for a translative movement with spondylolisthesis in an anterior or posterior direction decreasing the spinal canal by 2 – 3 mm Loss of disc height and hypermobility of facet joints can lead to loss of lordosis and
finally to kyphosis Dynamic changes and increasing kyphosis place increased
strain and shear forces on the spinal cord [16]
Biologic and Molecular Factors
Corticospinal tracts are very
vulnerable to ischemia
Vascular factors can play a significant role in the development of myelopathy.
Mechanical and vascular mechanisms can add to each other A compressed spi-nal cord will not tolerate a diminished perfusion and a margispi-nally vascularized
cord will not tolerate compression [98, 252] Blood supply of the different tracts
in the spinal cord impacts on the pattern of ischemia and subsequent axonal degeneration Transverse perforating vessels arising from the anterior sulcal arterial system are very susceptible to tension and likely to cause early ischemia and degeneration of the gray matter and medial white matter (anterior spinal
cord syndrome) [87] Spinal cord ischemia especially affects oligodendrocytes,
which results in demyelination exhibiting features of chronic degenerative disor-ders (e.g multiple sclerosis) [67] Particularly the corticospinal tracts are very vulnerable and undergo early demyelination initiating the pathologic changes of cervical myelopathy [40, 80, 95, 255]
Static mechanical factors causing compression, shear and distraction and dynamic repetitive compromise are seen as primary injury whereas ischemia and the subsequent cascade at the cellular and molecular level are considered as
secondary injury These secondary mechanisms include [80, 151, 204]:
) glutamatergic toxicity
) free radical-mediated cell injury
Trang 9) cationic-mediated cell injury
) apoptosis
Secondary cellular and molecular changes further compromise spinal cord function
Traumatic and ischemic injuries lead to an increase in extracellular levels of
glu-tamate, which is assumed to be excitotoxic leading to neuronal death The
gener-ation of free radicals and lipid peroxidgener-ation reactions may render neurons
sensi-tive to the excitotoxic effects of glutamate [80] The failure of the Na+-K+
-adeno-sine triphosphatase pump results in an accumulation of axonal Na+through
non-inactivated Na+channels The Na+channels can permit intracellular Ca2+entry
activating enzymes (e.g calpain, phospholipases and protein kinase C) resulting
in cytoskeletal injury [80] Apoptosis represents a fundamental biological
pro-cess that contributes to the progressive neurological deficits observed in
spondy-lotic cervical myelopathy [151] A common finding of many investigations of
spi-nal cord disorders is the observation that oligodendrocytes appear to be
particu-larly sensitive to a wide range of oxidative, chemical, and mechanical injuries, all
of which lead to oligodendrocyte apoptosis [67, 167, 255] The early apoptotic
loss of oligodendrocytes is assumed to precede axonal degeneration and
partici-pate in the expression of profound and irreversible neurological deficits caused
by destructive pathologic spinal cord changes under chronic mechanical
com-pression seen in CSM [16, 151]
Gene polymorphism
is associated with OPLL
A particular entity is the ossification of the posterior longitudinal ligament
(OPLL), which particularly affects Japanese individuals and leads to a
progres-sive stenosis of the cervical spinal canal and subsequently CSM [254] OPLL is a
multifactorial disease in which complex genetic as well as environmental factors
play a major role [134, 282] Gene analysis studies identified specific collagen
gene polymorphisms that may be associated with OPLL, which encode for
extra-cellular matrix proteins [134] Recently, it has been shown that polymorphism of
the nucleotide pyrophosphatase (NPPS) gene plays an important role in the
pathogenesis of OPLL [155, 186] NPPS is a membrane-bound glycoprotein
assumed to produce inorganic pyrophosphate which acts as a major inhibitor of
calcification and mineralization Furthermore, the involvement of many growth
factors and cytokines, including bone morphogenetic proteins and transforming
growth factor-q , were identified in various histochemical and cytochemical
anal-yses Recent epidemiological studies confirmed an earlier finding that diabetes
mellitus is a distinct risk factor for OPLL [134, 282]
Clinical Presentation
Patients with a degenerative cervical disorder can present with a spectrum of
symptoms ranging from benign, self-limiting neck pain to excruciating upper
extremity pain with progressive severe neurological deficits The primary goal of
the clinical assessment is to differentiate (see Chapter 8):
) specific cervical disorders, i.e with pathomorphological correlate
) non-specific cervical disorders, i.e without evident pathomorphological
correlate
In specific cervical disorders a pathomorphological (structural) correlate can be
found which is consistent with the clinical presentation Accordingly, in
non-spe-cific cervical disorders no such correlate can be detected Patients can only be
classified in the latter group after they have undergone a thorough clinical and
diagnostic work-up Patients frequently present with pain syndrome located in
the neck-shoulder-arm region, which sometimes makes it difficult to
differenti-ate neck and shoulder problems Before the diagnosis of non-specific neck pain
Degenerative Disorders of the Cervical Spine Chapter 17 435
Trang 10can be made, it is mandatory to exclude differential diagnoses, e.g shoulder pathology, or nerve entrapment syndromes In this chapter, we focus on a pathol-ogy oriented approach General aspects of history-taking and physical examina-tion are presented in Chapter 8
History
Differentiate neck and arm pain
The predominant symptom for patients with degenerative cervical disorders is
pain Rarely, patients present with neurological symptoms without pain The key
question in differentiating the origin of patients’ pain is (Table 2):
Table 2 Key question
) How much of your pain is in your arm(s)/hand(s) and in your neck/shoulder(s)?
In patients with predominant arm pain, the patients’ symptoms are frequently
part of a radicular or myelopathic syndrome (Table 3):
Table 3 Cardinal symptoms of radiculopathy and myelopathy
Radicular syndrome Myelopathic syndrome
) radicular pain ) numb, clumsy, painful hands ) sensory disturbances ) difficulty writing
) motor weakness ) disturbed fine motor skills ) reflex deficits ) difficulty walking
) symptoms of progressive tetraparesis (late) ) bowel and bladder dysfunction (late)
The key finding in patients with a radicular syndrome is radicular pain, i.e pain
following a dermatomal distribution The sensory, motor and reflex deficits are dependent on the affected nerve root It is important to note that the pain not
only radiates into the skin (dermatome) but also into the muscles (myotomes) and bone (sclerotomes) (see Chapter 8)
Differentiation of radicular
and referred arm pain
is sometimes difficult
The referred type of pain is sometimes difficult to differentiate from non-spe-cific radiating pain, which is not caused by a nerve root compromise The radicu-lar pain can be preceded by neck pain which results from an incipient disc herni-ation, i.e stretching of the anulus
Cervical radiculopathy can be caused by a:
) disc herniation
) spondylotic stenosis
Disturbed fine motor skills
may indicate CSM
In contrast to radiculopathy, a myelopathic syndrome can begin very subtly and can therefore pose a diagnostic challenge The leading symptoms are numb, clumsy, painful hands [192, 198] The examiner should particularly ask for
dis-turbed fine motor skills (particularly writing skills) The degree of neck pain is largely variable The pathoanatomical cause of the myelopathy characterizes the clinical presentation Patients with cervical myelopathy can present with a broad spectrum of signs and symptoms Cervical myelopathy is a clinical syndrome and dysfunction of the spinal cord, depending on the magnitude of spinal cord
dysfunction and its chronicity Early symptoms include diminished dexterity
and subtle changes in balance and gait Difficulty in manipulating small objects (e.g buttons, needles) is typical Myelopathy can concomitantly appear with radiculopathy since central stenosis is often combined with foraminal stenosis
In patients with predominant neck pain, the patients’ symptoms are fre-quently part of a so-called spondylotic syndrome ( Table 4)