Cervical Spine & Upper Limb Compressive Neuropathies Flashcards
spondylosis
As spondylosis can occur with disc degeneration leading to increased loading and accelerated OA of the facet joints.
spondylosis symptoms & treatment
Patients will complain of slow onset stiffness and pain in the neck which can radiate locally to shoulders and the occiput.
Physiotherapy and analgesics are the mainstay of treatment.
Osteophytes
can also impinge on the exiting nerve roots resulting in a radiculopathy involving the upper limb dermatomes and myotomes which may require decompression for severe symptoms resistant to conservative management.
disc prolapse
Acute and degenerative disc prolapse can also occur in the cervical spine producing neck pain and potentially nerve root compression.
Typically, the lower nerve root is involved (ie C7 root for C6/7 disc, C8 root for C7/T1 disc).
A large central prolapse can compress the cord leading to a myelopathy with upper motor neurone symptoms and signs.
disc prolapse symptoms & investigation
With nerve root compression, patients complain of shooting neuralgic pain down a dermatomal distribution with weakness and loss of reflexes depending on the nerve root affected.
Clinical findings and MRI will aid diagnosis of the affected level and again for cases resistant to conservative management, surgery may be considered (discectomy).
As with lumbar disc prolapse, the number of patients with asymptomatic disc prolapse increases with age resulting in a higher rate of “false positives” or “incidental findings” on MRI scanning.
Clinical findings should correlate with MRI findings before contemplating surgery.
cervical spine instability
Atraumatic cervical spine instability can occur in Down syndrome and rheumatoid arthritis.
Cervical spine instability
RA- atlanto‐axial subluxation can also occur due to destruction of the synovial joint between the atlas and the dens and rupture of the transverse ligament.
Again subluxation can result in cord compression which can be fatal.
Less severe cases (seen on flexion‐ extension views) may be treated with a collar to prevent flexion whilst more severe cases may require surgical fusion.
Lower cervical subluxations can occur due to destruction of the synovial facet joints and uncovertebral joints again with potential for cord compression (myelopathy) with upper motor neuron signs (wide based gait, weakness, increased tone, upgoing plantar response).
Again measurements are taken from flexion‐extension xrays and more severe cases may require stabilization/fusion.
Upper limb compressive neuropathies
In contrast to cervical nerve root compression, peripheral nerve compression neuropathies will cause symptoms and signs affecting peripheral nerve sensory and motor territories rather than dermatomal and myotomal distributions.
The compressive neuropathy syndromes are a very common cause of presentation to orthopaedics; particularly carpal tunnel syndrome.
Carpal tunnel syndrome
The carpal tunnel of the wrist is formed by the carpal bones and the flexor retinaculum.
The median nerve passes through the carpal tunnel along with 9 flexor tendons (FDS & FDP to 4 digits + FPL) with their synovial covering. Any swelling within the confines of the carpal tunnel may result in median nerve compression.
Whilst the flexor tendons are not particularly susceptible to pressure, nerves are highly sensitive to this problem.
Carpal tunnel synd causes
may be idiopathic (most cases), it can occur secondary to many conditions including rheumatoid arthritis (synovitis > less space) and conditions resulting in fluid retention – pregnancy, diabetes, chronic renal failure, hypothyroidism (myxoedema).
can also be a consequence of fractures around the wrist (especially a Colles fracture). With pregnancy the symptoms usually subside after childbirth.
Women are affected up to 8 times more than men.
Carpal tunnel syndrome symptoms
parathesiae in the median nerve innervated digits (thumb and radial 2½ fingers) which is usually worse at night, loss of sensation and sometimes weakness of the thumb or clumsiness in the areas of the hand supplied by the median nerve.
Carpal tunnel syndrome exam & investigation
On examination there may be demonstrable loss of sensation and/or muscle wasting of the thenar eminence (with chronic sever cases).
Symptoms can be reproduced by performing Tinel’s test (percussing over the median nerve) or Phalen’s test, holding the wrists hyper‐flexed (which decreases space in the carpal tunnel.
Nerve conduction studies confirm the diagnosis with slowing of conduction across the wrist.
Carpal tunnel syndrome Treatment
Non-operative treatment includes the use of wrist splints at night to prevent flexion. Injection of corticosteroid can also be used.
Surgical treatment: Carpal tunnel decompression involves division of the transverse carpal ligament under local anaesthetic (one of the most commonly performed surgical procedures). It is usually a highly successful operation, although there is risk of damage to the median nerve or one of it’s smaller branches.
Cubital tunnel syndrome
This involves compression of the ulnar nerve at the elbow behind the medial epicondyle (”funny bone” area).
Cubital tunnel syndrome causes
Compression can be due to a tight band of fascia forming the roof of the tunnel (known as Osborne’s fascia) or due to tightness at the intermuscular septum as the nerve passes through or between the two heads at the origin of flexor carpi ulnaris.
