Carpal tunnel Flashcards
Where is the carpal tunnel located?
What is the function of the carpal tunnel?
Proximal portion of the wrist
Serves as the entrance to the palm for several tendons and the median nerve
What are the borders of the carpal tunnel?
Formed posterially by the carpal bones
Formed laterally by the scaphoid and trapezium tubercles
Formed medially by the hook of the hamate and psifrom
Formed superiorly by the flexor retinaculum (connective tissue)
What are the contents of the carpal tunnel?
9 tendons surrounded by synovial sheatsh and teh median nerve.
Four tendons of flexor digitorum profundus
Four tendons of digitorum superficialis
Tendon of flexor pollicus longus
What are the three divisions of the median nerve and how is the carpal tunnel involved?
Palmar cutaneous branches- given off prior to the carpal tunnel
Recurrent brach- divides after exiting carpal tunnel, supplies thenar muscle group
Palmar digital nerves- again divides after tunnel, gives off sensory innervation.
What is carpal tunnel syndrome?
Compression of the median nerve within the carpal tunnel. Most common mononeuropathy. May be caused by thickened ligaments and tendon sheaths although the cause may also be idiopathic
What are the clinical signs of carpal tunnel syndrome?
Weakness and atrophy of the thenar muscles
Numbness, tingling and pain in the median nerve distribution area.
Pain typically radiates from the forearm and gets worse overnight, waking up patients from their sleep
How do you test for carpal tunnel syndrome?
Tinel’s test- tapping carpal tunnel. If pain is elicited Tinels test positive
Phalens manoeuvre- reverse prayer sign for 60s if numbness/pain elicited then Phalens positive
How do you treat carpal tunnel syndrome?
Splint holding the wrist in dorsiflexion overnight to relieve symptoms. If this is unsuccessful then corticosteroids can be injected.
What tendon is found not within the carpal tunnel but within flexor retinaculum itself
Carpi radialis tendon
