Cervical spondylosis

definition

· chronic disc degeneration and associated facet arthropathy

epidemiology

· usually begins at age 40-50

· more common in men

· most common at

· C5-6

· C6-7

· C4-5

· myelopathy is commonest type of cord dysfunction in patients age > 55 yrs

· frequently underdiagnosed

pathogenesis

Spondylosis

· due to degenerative changes at

· disc

· facet joints

· uncovertebral joints

Radiculopathy

· roots compressed by

· chondro-osseous spurs of uncovertebral joints

· degenerative disc herniation

· redundancy of ligamentum flavum

Myelopathy

· cord impinged when canal diameter reduced

· causes as for radiculopathy

· stenosis contributed to by

· congenitally narrow canal

· ossification of posterior longitudinal ligament (esp. Orientals)

· vertebral subluxation

· loss of cervical lordosis

· neurological deficit contributed to by

· cord demyelination

· compression of anterior spinal artery

clinical features

Neck

Symptoms

· neck pain

· grating feeling

· radiation of pain to shoulder

· headaches

Signs

· local tenderness

· limited ROM

Radiculopathy

· usually involves lower root

· ie. C6 root at C5-6

· findings may overlap

· because of intraneural intersegmental connections

Symptoms

· pain radiating down arm

· parasthesiae in arm

Signs

· weakness

· sensory disturbance

· diminished reflexes

Myelopathy

· usually affects anterior +/- central column

Symptoms

· may be precipated by minor trauma (esp. hyperextension)

· weakness and parasthesiae

· arms > legs

· difficulty walking

· Lhermitte sign

· lightning-like sensation radiating down back to feet

· with neck flexion

· urinary retention or incontinence

Signs

· predominantly LMN signs in arms

· may be UMN signs

· eg. Hoffman’s sign

· UMN signs in legs

· hyper-reflexia

· clonus

· positive Babinski reflex

· abnormal gait

· ataxic, broad-based, shuffling

radiology

Plain x-rays

· typical changes of spondylosis

· disc space narrowing

· osteophyte formation

· degeneration in facet and uncovertebral joints

· may be present in asymptomatic individuals

· foraminal stenosis seen on oblique films

· central stenosis defined as

· reduction of canal width from 17 mm (normal) to to 13 mm (relative stenosis) or 10 mm (absolute stenosis)

· reduction of Pavlov ratio (canal-vertebral body width) from 1.0 to < 0.85

CT scan

· confirms degenerative changes

· may demonstrate posterior osteophytes and disc herniation

MRI

· demonstrates

· neural compression

· intrinsic cord changes

· high incidence of false positives

· disc degeneration in 25% < age 40 and 57% > age 40 of asymptomatic subjects

· excludes other possible causes in

· cord

· brain

other tests

Nerve conduction studies

· abnormalities in somatosensory evoked potentials

· may be H-wave

differential diagnosis

Radiculopathy

· carpal tunnel syndrome

· impingement

· cervical tumour

· thoracic outlet syndrome

Myelopathy

· multiple sclerosis

· cerebrovascular disease

· intracranial tumour

· syrinx

· spinal cord ischaemia

· myopathies and neuropathies

treatment

Nonoperative

· analgesics

· local modalities

· exercise programme

· cervical traction

Operative

Indications

· spondylosis alone

· rarely indicated

· radiculopathy

· disabling pain WITH

· significant weakness

· myelopathy

· neurological progression

· ? should not wait until severe neurological compromise

Technique

Radiculopathy

· anterior approach

· Smith Robinson discectomy

· excision of osteophytes

· interbody fusion with iliac crest graft

Myelopathy

· anterior approach

· multiple vertebrecomy

· excision of osteophytes

· iliac crest strut graft

Complications

· pseudarthrosis

· graft displacement

· neurological injury

· injury to other structures

· recurrent laryngeal nerve

· superior laryngeal nerve

· carotid artery

· oesophagus