Examination of the Hand Flashcards
What is the palmar surface of the hand aka?
Volar
What is the back surface of the hand also known as?
Dorsal surface
Where are the flexor tendon located?
Volar surface of hand
Where are the extensor tendons located?
Dorsal surface of hand
What is the thenar eminence?
Soft tissue bulk on the volar surface proximal to the thumb
It contains the intrinsic muscles of the thumb
What is the hypothenar eminence?
Soft tissue bulk on volar surface of hand proximal to pinky
Contains intrinsic muscles of the pinky
What are the bones of the hands?
Carpals (8 bones of wrist)
Metacarpals (1 to 5)
Phalanges (3 per finger, 2 for thumb)
What joints exist between the carpal and metacarpal bones?
Carpo-metacarpal joints
What joints exist between the metacarpal and phalangeal bones?
Metacarpo-phalangeal joints
What joints exist between the phalangeal bones?
Interphalangeal point (proximal and distal)
What forms the carpal tunnel?
Carpal arch of the carpal bones
Flexor retinaculum forms roof
What passes through the carpal tunnel?
Median nerve
9 flexor tendons of the digits
What muscles make up the thenar eminence? State their function
Opponens pollicis - opposition of thumb
Abductor pollicis brevis - abduction of thumb
Flexor pollicis brevis - flexion of thumb
What muscles make up the hypothenar eminence? State their function
Opponens digiti minimi - opposition of little finger
Abductor digiti minimi - abduction of little finger
Flexor digiti minimi - flexion of little finger
What muscles exist between metacarpal bones?
Interosseous muscles (dorsal and volar)
How many dorsal interossei are there? What is their role?
4
Abduction of fingers
How many volar dorsal interossei are there? What are their role?
3
Adduction of fingers
Where are the lumbrical muscles found?
FDP tendons
What is the role of the lumbrical muscles?
Flexion of MCP
Extension of PIP and DIP
What is the action of palmaris brevis?
Helps improve grip
What is the action of adductor pollicis?
Adduction of thumb
What are the extrinsic muscles of the hand?
Flexor digitorum superficialis Flexor digitorum profundus Flexor pollicis longus Flexor carpi radialis Flexor carpi ulnaris
Where does the tendon of the FDS insert and what is its role?
Inserts on middle phalange so allows flexion of PIP
Where does the tendon of the FDP insert and what is its role?
Inserts on distal phalanges so allows flexion of DIP
Where does the tendon of the flexor pollicis longus insert and what is its role?
On distal phalanx of thumb, so allows flexion of thumb
What is the role of flexor capri radialis?
Abduction of hand
What is the role of flexor capri ulnaris?
Adduction of the hand
What muscles are found in the 1st extensor compartment and what are their roles?
Abductor pollicis longus (abduction of thumb)
Extensor pollicis brevis (extension of proximal phalanx of thumb)
What muscles are found in the 2nd extensor compartment and what are their roles?
Extensor carpi radialis longus and brevis (extension + abduction of wrist)
What muscle is found in the 3rd extensor compartment and what is its r role?
Extensor pollicis longus (extends distal phalanx of thumb)
What muscles are found in the 4th extensor compartment and what are their roles?
Extensor digitorum (extends digits expect thumb and extends wrist) Extensor indicis proprius (extends index finger)
What muscles are found in the 5th extensor compartment and what are their roles?
Extensor digiti minimi (extension of little finger)
What muscle is found in the 6th extensor compartment and what is its role?
Extensor carpi ulnaris (extension + adduction of wrist)
What are the extensor hoods?
Formed by the tendons of the ED and EPL
An important site of attachment for many intrinsic muscles
What tendon forms the palmar apnoeurosis?
Palmaris longus tendon
What is the anatomical snuffbox?
Triangular depression on posterolateral side of wrist
What forms the borders of the anatomical snuffbox?
Lat - abductor pollicis longus + extensor pollicis brevis
Med - extensor pollicis longus
Floor - scaphoid + trapezium
What are the contents of the anatomical snuffbox?
Extensor carpi radialis longus and brevis
Radial artery
Radial nerve
Cephalic vein
What is the blood supply to the hand?
Ulnar + radial arteries which form the superficial and deep palmar arches
Where does the ulnar artery supply?
Side of index finger, middle, ring and little finger
What are the branches of the ulnar artery?
Deep palmar branch (anastomoses with deep palmar arch formed by radial artery)
Palmar digital artery (supplies ulnar side of little finger)
3 common palmar digital arteries (branch into proper palmar digital arteries to supply radial side of little finger, ring and middle finger and ulnar side of index finger)
Where does the radial artery supply?
Radial side of index finger, thumb
What four branches does the radial artery become?
Princeps pollicis artery and radialis indicis artery
Dorsal carpal + dorsal metacarpal branches supply dorsal aspect of hand
What artery supplies the dorsal interossei?
Radial
What is the venous drainage of the hand?
Interconnected networks of deep and superficial veins
From what side of the hand does the cephalic vein arise?
Radial
From what side of the hand does the basilic vein arise?
Ulnar
What is the distribution of the radial nerve?
Dorsal surface from thumb to middle finger
What is the distribution of the median nerve?
Thumb, index, middle and half of ring finger
What is the distribution of the ulnar nerve?
Little finger and half of ring finger
Motor supply to all intrinsic muscles expect thenar muscles and lateral 2 lumbricals
Why is it essential to treat swelling of the hand?
If left untreated it will encourage a fibroblastic change causing moving parts of the hand to adhere –> loss of function
How can we minimise swelling of the hand?
Keeping it elevated
What are the purposes of splinting?
Protect injured structures
Prevent joint contracture
Prevent development of strong substitution patterns
Maximise functional use of hand
Should you tell the patient to avoid moving the hand when its in a splint?
No encourage controlled active mobilisation (i.e. movement within the splint as this helps with rehab)
What are the different ways of immobilising the hand?
Hand cast
Buddy splint - for finger injuries (tape fingers together)
FDP and FDS splint - when flexors of fingers injured
FPL splint
FCR and FCU splint
ED splint
etc.
How should you manage a burnt hand?
Put in clear bag, elevate to reduce swelling, move fingers + wrist to prevent adhesions/contractions
Pain relief
Excision of dead tissue, appropriate surgery
How should you manage a hand infection?
Elevation Rest Antibiotics (swab wound first) Incision + drainage if pus present Tetanus prophylaxis for open wounds
What is paronychia?
Infection of skin fold that sits over the finger nail
What tends to cause paronychia?
Nail biting or aggressive manicure
How does paronychia present?
Painful, swollen, red nail fold
Who does chronic paronychia tend to occur in?
Those who constantly have wet hands, e.g. bartenders, usually a fungal infection
What is felon?
Infection of distal pad of finger usually caused by puncture of finger tip by thorn or splinter
What is tenosynovitis?
Infection of flexor tendon sheath
What are the 4 signs of tenosynovitis?
Partially flexed posture of finger
Pain with passive finger extension over the palmar side of finger
Pain to touch over palmar side of finger
Circumferential swelling around entire finger
What is the commonest organism from a human bite to cause infection in the hand?
Eikenella corrodens
