Spine: Spondylosis

Question 1

Define spondylosis.

Answer 1

Progressive degenerative process affecting the (cervical) vertebral bodies and intervertebral discs, and causing compression of the spinal cord and/or nerve roots.

Question 2

What is the aetiology of spinal spondylosis?

Answer 2

Osterarthritic degeneration of vertebral bodies –> osteophytes which protrude on to the exit foramina and spinal canal –> compression of nerve roots (radiculopathy) or anterior spinal cord (myelopathy)

Question 3

How common is spondylosis and what is the mean age of diagnosis?

Answer 3

107/100000 incidence in men and 64/100000 incidence in women

Mean age of diagnosis is 48 years

Question 4

What is the typical presentation of (cervical) spondylosis?

Answer 4

• Neck pain or stiffness
• Arm pain (stabbing or dull ache)
• Paraesthesia, weakness, clumsiness in hands
• Weak and stiff legs, gait disturbance
• Atypical chest pain, breast pain or pain in the face

Question 5

What are the signs of cervical spondylosis on examination? (Arms/legs)

Answer 5

Arms:

• Atrophy of forearm/hand muscles
• Segmental muscle weakness in nerve distribtion
• Hyporeflexia, Hoffmann’s sign
• Sensory loss (mainly in pain and temperature)
• Pseudoathetosis - writhing finger motions when hands are outstretched, fingers spread and eyes closed

Legs:

• (seen in those with cervical cord compression)
• Increased tone
• Decreased vibration and proprioception with sensory level

Lhermitte’s signs

Question 6

What are the functions of C5-C8?

(weaknesses may occur in these in spondylosis)

Answer 6

• C5 - shoulder abduction and elbow flexion
• C6 - elbow flexion and wrist extension
• C7 - elbow extension, wrist extesnion, finger extension
• C8 - wrist flexion and finger flexion

Segmental muslce weaknesses can occur in these

Question 7

What kind of reflexes may be seen in C5/6 lesions and what is the cause of these?

Answer 7

“inverted” reflexes may be seen as a result of LMN impairment at the level of compression and UMN impairment below the level

hyporeflexia

Question 8

What is Hoffmann’s sign?

Answer 8

Hoffmann’s sign - flexion of the terminal thumb phalanx when rapidly extending the terminal phalanx of the 2nd or 3rd finger

Question 9

What is Lhermitte’s sign?

Answer 9

Neck flexion produces crepitus and/or paraeshesia down the spine

Question 10

What investigations would you do for spondylosis?

Answer 10

Spinal XR LATERAL - may detect OA change in cervical spine but rarely diagnostic in non-tramatic cervical radiculopathy. Flexion and extension films are useful to evaluate possibility of subluxation of one vertebral body over another.

MRI - assess root and cord compression and excludes tumour + nerve root infiltration by tumour/granulomatous tissue. Many elderly may have some spondylosis and this may or may not cause symptoms.

Needle EMG - may reveal myotomal pattern of denervation

Question 11

Question 12

What is the pathogenesis of cervical spondylosis?

Answer 12

• Degeneration of annulus fibrosus (the tough coating of the intervertebral discs)
• Combined with osteophyte formation on adjacent vertebra leading to narrowing of the spinal canal and intervertebral foramina
• As neck flexes and extends, the cord is dragged over these protruding body spurs anteriorly and indented by a thickened ligamentum flavum posteriorly

Question 13

Summarise the presenting complaint and signs.

Answer 13

Presenting complaint

• Neck stiffness (but common in anyone >50yrs old),
• crepitus on moving neck,
• stabbing or dull arm pain (brachialgia),
• forearm/wrist pain.

Signs

• Limited, painful neck movement ± crepitus (examine gently).
• Neck flexion may produce tingling down the spine (Lhermitte’s sign).
• nb: this does not distinguish between cord or roots (or both) involvement.