Upper Limb Compressive Neuropathies Flashcards
What are the contents of the carpal tunnel?
9 flexor tendons
- Flexor Digitorum Superficialis to 4 digit
- Flexor Digitorum Profundus to 4 digits
- Flexor Pollicis Longus
And the Median nerve
What are some of the possible causes of carpal tunnel syndrome?
Anything that causes loss of space in the carpal tunnel and compression of the median nerve
RA
Fluid retention - pregnancy, diabetes, chronic renal failure, hypothyroidism
Wrist fractures - especially Colle’s fracture
Women are 8 times more likely than men to develop CTS
What is the difference between a Colle’s fracture and a Smith’s fracture?
Both are fractures of the distal radius
In a Colle’s fracture, the distal segment of the radius is displaced dorsally, and this injury is classically caused by FOOSH
In a Smith’s fracture, the distal segment of the radius is displaced palmarly
How does Carpal Tunnel Syndrome classically present?
Parasthaesia over the thumb, index and middle fingers which is worse at night
May see some wasting of the thenar eminence
Weakness in the thumb
What are Tinel’s Test and Phalen’s Test?
Used to test for Carpal Tunnel Syndrome
Tinel’s Test - percussing over median nerve elicits symptoms of CTS
Phalen’s Test - holding the wrist in a hyperflexed postion to reduce space in the carpal tunnel
What nerve is compressed in Cubital Tunnel Syndrome?
The ulnar nerve is compressed behind the medial epicondyle of the humerus
Cubital Tunnel Syndrome - presentation, and what test can be done to confirm?
Parasthaesia in the 4th and 5th fingers
Weakness may be seen in abduction of the index finger (1st dorsal interosseous) and abductor pollicis
Weakness of abductor pollicis can be confirmed using Froment’s Test (weakness of adductor pollicis means patient compensates action by flexing flexor policis longus of the thumb to maintain grip strength)
What other test can be done to assess for Ulnar nerve compression?
Tinel’s test (as with cubital tunnel syndrome) - percussing over the nerve elicits symptoms
