Dissection 6/7 Flashcards
How can infections in the deep hand spread to the anterior compartment of the forearm?
Via the midpalmar space and via the carpal tunnel
Optimal grip power of the hand occurs in the wrist in which position?
Extended
Movement produced by the interossei muscles
Abduct/adduct (PAD DAB)
Movement produced by the lumbricals?
Flexion of the MCP joints
Extension of PIP joints of the figners
Venous drainage of the hand
Deep: follows arteries
Superficial: dorsal venous network
How does lymph drain from the hand?
Via the cubital and axillary nodes
In the DRUJ, which bone pivots around the other?
The radius pivots around the ulna
Another name for the transverse carpal ligament?
The flexor retinaculum
The tendon of which muscle fuses with the retinaculum?
Palmaris longus
What is the carpal tunnel?
The carpal bones and the flexor retinaculum
Which tendons enter the carpal tunnel?
FDS, FDP, FPL
median nerve also
Which branch of median nerve is spared in carpal tunnel syndrome?
Palmar cutaneous branch
Why is the central palm spared in carpal tunnel syndrome?
Supplied by palmar cutaneous branch (does not pass through carpal tunnel = not compressed)
Supplies the palmaris brevis
Palmar cutaneous branch
Supplies the muscles of the thenar eminence?
Recurrent branch of the median nerve
Which nerve and artery course immediately lateral to this carpal bone?
Ulnar nerve and artery
Which arteries form the superficial palmar arch?
The superficial palmar branch of the ulnar artery and the superficial palmar branch of the radial
(superficial palmar arch is immediately deep to the palmar aponuerosis)
Arteries which form the deep palmar arch?
The deep branch of the radial artery and the deep branch of the ulnar artery
(deep branch runs across the anterior aspects of the bases of the metacarpals)
Pathology affecting the palmar fascia. It causes thickening and shortening (contracture) leading to fixed flexion deformity
Dupuytrens
How to identify FPL tendon?
It has its own sheath (posterior to median nerve)
Do not get this confused with PALMARIS longus which attaches to flexor retinaculum)
What are the common palmar digital arteries?
Arise from superficial palmar arch
Then bifurcate into a pair of proper palmar digital arteries near the base of the fingers
Where does the radial artery bifurcate?
Proximal to the carpal tunnel
What is a ring block?
Anaesthetic put in a “ring” around the finger to anaesthetise all four proper digital nerves
(adrenaline must not be used)
Neurovascular supply of the fingers
Each finger has 4 neurovascular bundles supplying it:
- medial palmar
- lateral palmar
- medial dorsal
- lateral dorsal
Part of the hand supplied by the ulnar nerve?
Medial part of palm
Little finger
Medial half of the ring finger
Part of the hand supplied by the median nerve
Central/lateral palm
Medial half of the ring finger
Middle and index finger
Thumb (APART FROM SKIN AT THE BASE)
Part of the hand supplied by the radial nerve
Skin at the base of the thumb
Nerve supply to abductor pollicis brevis
Median
Nerve supply of flexor pollicis bevis
Median
Nerve supply of opponens pollisi
Median
Superficial muscles of the thumb
Abductor pollicis brevis (proximal)
Flexor pollicis brevis (distal)
Deep muscle of the thumb
Opponens pollicis
Superficial muscles of the hypothenar eminence?
Abductor digiti minimi (medially)
Flexor digit minimi brevis (laterally)
Deep layer of the hypothenar eminence?
Opponens digiti minimi
The tendons of the FDS attach to which phalanges?
Proximal phalanges
The tendons of the FDP and FPL attach to which phalanges?
Distal phalanges
Borders of the anatomical snuffbox?
Anterior: abductor pollicis longus tendon, extensor pollicis brevis tendon
Posterior: extensor pollicis longus tendon
Floor (deep): scaphoid, trapezium
How many lumbricals do you have?
4 (1 for each finger)
Nerve supply to the lumbricals
Medial 2 lumbricals: ulnar
Lateral 2 lumbricals: median
Action of the lumbricals and where they span?
Flexion at the MCPs and extension at the PIP
- span anterior aspect of MCPs
- span posterior aspect of DIPs
Where do the interosseous muscles attach?
MCPs to PIP
(different from lumbricals which are MCP to DIP) yaaaay finally makes sense
Nerve supply to the interossei
Ulnar nerve
