Carpal Tunnel Syndrome Flashcards
What is carpal tunnel syndrome?
Compression of the median nerve within the carpal tunnel fo the wrist due to a raised pressure within the compartment
What are the border and contents of the carpal tunnel?
Deep carpal arch Lateral by scaphoid and trapezium tubercles Medially by hook of hamate and pisiform Superficially - flexor retinaculum (CT Contents: Tendon of flexor pollicis longs 4 tendons of flexor digitorum superficially 4 tendons of flexor digitorum profundus Median nerve
What does compression of the median nerve lead to?
Pain, numbness and paresthesia in the lateral 3.5 digits
Risk factors
female gender 45-60 pregnancy obesity previous injury to wrist repetitive hand or wrist movment
What are the clinical features of CTS?
pain, numbness ± paraesthesia throughout median nerve sensory distribution
Palmar sparing due to palmar cutaneous branch of the median nerve branching proximal to the flexor retinaculum and passing over the carpal tunnel
Symptoms worse at night and temporarily relieved by hanging the affected arm over the side of the bed or by shaking it
What tests can you do for CTS?
Tinel’s test, extend wrist and percuss over median nerve produces sensory symptoms
Phalen’s test - reverse prayer sign for one minute produces symptoms
In the later stages of CTS, weakness of thumb abduction due to denervation atrophy of thenar muscles ± wasting of thenar eminence
What are some differential for CTS?
Cervical radiculopathy - C6 nerve root involvement may produce pain/paraesthesia in a similar distribution however will likely have an element of neck pain or symptoms involving the entire arm length
Pronator teres syndrome (median nerve compression by pronator teres)
Symptoms will also extend to proximal forearm and sensation of the palm will be reduced
Flexor carpi radialis tenosynovitis - tenderness at base of thumb
How is diagnosis of CTS made?
clnical
How is CTS managed?
Conservative - wrist splint (commonly worn at night, preventing wrist flexion and holds the wrist as to not exacerbate the paraesthesia and pain alongside physiotherapy and training exercises.
Medical - corticosteroid injections to reduce swelling,
Surgical (only in severely limiting cases where previous treatment has failed) = carpal tunnel release surgery decompresses the carpal tunnel involving cutting through the flexor retinaculum, reducing pressure on the median nerve under local anaesthetic - day case
What are complications of CTS
permanent neurological impairment that will not improve with surgery
Causes?
MEDIAN TRAP Myxoedema Oedema - heart failure Diabetes melitus Idiopathic Amyloidosis Neoplasia
Trauma - lunate fracture
RA
Acromegaly
Pregnancy
