Hand Flashcards
What sort of joint are the intercarpal and carpometacarpal joints?
Plane joints allowing sliding/translation movements.
What sort of joints are the trapeziometacarpal joint?
Specialized CMC joint acting as a saddle.
This is the thumb joint.
Allows flexion/extension, abduction/adduction, opposition.
What type of joint is the metacarpophalangeal joint?
Condyloid allowing flexion/extension
Abduction and adduction.
What sort of joint are the interphalangeal joints?
These are hinge joints working to flex and extend.
What bone is most commonly broken in the hand when falling with your palms outstretched?
The Scaphoid, the inferior aspect can lost its blood supply.
What occurs in a Jersey finger injury?
Rupture/ avulsion of the FDP tendon from base of distal phalanx.
Leads to inability to flex at DIP joint of affected digit.
What occurs in a mallet finger injury?
Sudden impact forces distal phalanx into hyperflexion due to an avulsion of the extensor expansion.
Leads to inability to extend DIP joint of affected digit.
What nerve innervates the thenar eminance?
The superficial branch of the median nerve.
What nerve innervates the hypothenar compartment?
The Deep branch of the ulnar nerve.
What nerves innervate the then flexor pollicis brevis?
The flexor pollicus brevis has two heads. The superficial head is innervated by the recurrent branch of the median nerve. The deep head of the muscle is innervated by the deep branch of the ulnar nerve.
What nerve innervates the muscles of the hypothenar group?
These muscle are innervated by the deep ulnar nerve.
What is the function of the lumbricles?
These 4 extend at the IP joints and flex at the MCP joints
What is the innervation to the lumbricles?
The lateral 2 are innervated by the median nerve
The medial 2 are innervated by the deep ulnar
**Same innervation pattern as what the flexor digitorum profundus has.
What nerve innervates both the palmar and dorsal interossei?
What nerve innervates the adductor policus?
The deep ulnar nerve!
Describe the blood supply to the digits of the hand and metacarpal bones.
The superficial palmar arch gives rise to three common digital arteries. These will then give rise to 6-7 proper digital arteries.
The pinky gets a proper palmar digital artery to its self (No common)
Describe the blood supply to the thumb.
Superficial radial artery links up with the ulnar through the abductor pollicus brevis to form the superficial palmar arch.
The radial artery wraps to the posterior forming the princeps pollicus artery that will give rise to the radialis indicus and the digital artery of the thumb.
The princeps pollicus also contoninues to form the deep arch.
What cutaneous innervation does the ulnar nerve provide?
Provides innervation to medial palm and lateral 1.5 digits both anteriorly and posteriorly.
What cutaneous innervation is provided by the median nerve to the hand?
The median nerve supplies the lateral 3.5 digits anteriorly as well as there nail beds.
What cutaneous innervation is provided by the radial nerve?
The dorsal aspect of the lateral 3 digits not including the nail beds.
What is guyons canal?
Narrow space between the pisiform and hamate through which the ulnar nerve passes and can be compressed.
What is a type I Guyons canal compression?
Ulnar nerve trunk compressed proximally leading to loss of motor and cutaneous
What is a type II Guyons canal compression?
Deep branch of ulnar nerve compressed leading to loss of motor
What is a type III guyons canal compression?
Compression of the cutaneous ulnar nerve having sensory loss only.
What are the muscle innervated by the median nerve?
LOAF 1/2 lumbricles Opponens pollicus Abductor pollicus brevis Flexor pollicus brevis
What are the contents of the carpal tunnel?
9 tendons
FDP
FDS
FPL
What causes Ape hand?
Prolonged carpal tunnell leading to loss of the thenar muscles
Thumb will be adducted and externally rotate.
What would loss to the recurrent branch of the ulnar nerve lead to?
Ape hand!
Supplies the thenar muscles only.
