Flashcards in The Hand and Wrist Deck (14)
The antebrachial (deep) fascia of the anterior forearm thickens distally, firstly as the _____1______ at the aspect of the wrist joint then, distally and deeper, as the _______2__________.
The flexor retinaculum attaches to _____3__________.
The retinaculum prevents_____4_____ of the tendons during flexion, which would reduce muscle efficiency.
The distal tendon of _____5_______ fuses with and strengthens the flexor retinaculum.
1) palmar carpal ligament
2) flexor retinaculum (transverse carpal ligament)
3) the scaphoid/trapezoid laterally and the pisiform and hamate medially
5) palmaris longus
What is the carpal tunnel?
combination of the carpal bones (posteriorly) and the flexor retinaculum (anteriorly).
What are the contents of the carpal tunnel?
The long tendons of the forearm flexor muscles (FDS, FDP and FPL) and the median nerve enter the palm via the carpal tunnel.
Explain carpal tunnel syndrome?
Carpal Tunnel Syndrome is the result of compression of the median due to swelling in the tunnel. The palmar cutaneous branch of the median nerve is given off proximal to the tunnel and travels superficially to reach the skin of the palm. It is therefore spared in carpal tunnel syndrome so sensation of the central palm is unaffected.
The superficial palmar branch of the ulnar artery forms the _____1_____ immediately deep to the palmar aponeurosis by anastomosing with the superficial palmar branch of the radial artery.
The deep branch forms the _____2_______ (which runs across the anterior aspects of the bases of the metacarpals) by anastomosing with the deep branch of the ulnar artery.
1) superficial palmar arch
2) deep palmar arch
What is Dupuytrens contracture?
Dupuytren’s Contracture is a pathology affecting the palmar fascia. It causes thickening and shortening (contracture) leading to fixed flexion deformities of, in particular, the ring and little fingers.
Each finger has four neurovascular bundles supplying it......
Medial palmar, lateral palmar, medial dorsal and lateral dorsal.
Describe ring block technique
This technique is commonly used to anaesthetise a finger. This involves depositing local anaesthetic in a “ring” around the base of the finger to anaesthetise all four proper digital nerves. Suturing or minor surgery can then be performed painlessly distal to the block. The proper digital arteries are end arteries and care should be taken when administering a local anaesthetic in cases where it contains adrenaline.
Describe fibrous digital sheaths
continuous with the longitudinal digital bands of the palmar aponeurosis.
The sheaths attach to both sides of the phalanges and form a secure tunnel through which the FDS, FDP and FPL tendons and their synovial sheaths travel distally.
The tendons attach to the middle (FDS) and distal (FDP & FPL) phalanges respectively.
What is clinically suggestive of a scaphoid fracture?
Tenderness in the floor of the anatomical snuff box following trauma (e.g. fall onto hand with extended/abducted wrist.
There are __1____lumbricals: one for each finger.
The lumbricals attach between the ______2_________
They span the ___3___ aspect of the 2nd to 5th MCP joints and then the ____4____ aspect of the 2nd to 5th PIP joints. Their action is therefore to ______5________
The medial two lumbricals are supplied by the ____6____and the lateral two by the ____7____ nerve.
2) FDP tendon and the extensor expansion of the same digit.
5) flex the MCP and extend the PIP joints.
What do the palmar interossei muscles do?
Adduct the digits
What do the dorsal interossei muscles do?
Abduct the digits