Hand Flashcards
What is a Boxers fracture?
Fracture of the fifth metacarpal (pinky)
What is the most mobile joint in digits 2-5?
MP
Flexion/extension of digits 2-5 occurs at which joints?
MP
PIP
DIP
Thumb adduction/abduction is in a plane _____ to the plane of the palm.
Perpendicular
Thumb flexion/extension is in a plane _____ to the plane of the palm.
Parallel
What are the ligaments on the sides of finger joints?
Collateral ligaments
What does the volar plate do in the finger?
Centers the long flexor tendons and protects against hyperxtension. On the palmar side of the finger
What are the attachments of the flexor digitorum superficialis?
Epicondyle of humerus
Base of middle phalanx digits 2-5.
What is the action of the flexor digitorum superficialis?
Flex PIP joint
What is the innervation of the flexor digitorum superficialis?
Median nerve
What is the action of the flexor digitorum profundus?
Proximal ulna
Base of distal phalanx digits 2-5
What is the action of the flexor digitorum profundus?
Flexes DIP joint
What is the innervation of the flexor digitorum profundus?
Ulnar nerve (medial) AND AIN (lateral)
What are the portions of the tendons of the fingers?
Tendon -> tendon sheet (promotes gliding) -> retinacular portion (pulleys that stabilize the tendon and prevent bow-stringing)
What are the attachments of the extensor digitorum?
Lateral epicondyle Extensor expansion (hood)
What is the action of the extensor digitorum?
Extend MP joint (and also IP)
What is the innervation of the extensor digitorum?
Posterior interosseous nerve (PIN)
What is the innervation of the extensor indicis proprius and digiti minimi?
PIN
What is the juncturae tendinum?
Intertendinous connections that couples the actions of digits 2-5
What is the extensor/expansion hood?
A moveable attachment sheath that drapes over the dorsal part of the digits. When ED contracts, the hood is pulled proximally and extends the IP
What is the flexor pollicis longus?
Anterior ragius -> distal phalanx of thumb, flexes IP.
What is the innervation of the flexor pollicis longus?
AIN
How you clinically test AIN?
Make an “ok” sign. Due to loss of FPL and FDP, cant make round circle.
What are the attachments of the extensor pollicis longus?
Posterior distal ulna
Base of distal phalanx of thumb
What are the innervations of EPL and EPB?
PIN
What are the attachments of the extensor pollicis brevis?
Posterior distal ulna
Base of proximal phalanx of thumb
What are the attachments of the abductor pollicis longus?
Posterior distal radius and ulna
Base of first MC
Abducts the thumb
What is the innervation of ABPL?
PIN
What De Quervain’s Tenosynovitis? How do you test it?
Inflammation of the extensor pollicis brevis and abductor pollicis longus tendons as they glide over radial styloid.
Tested by Finkelstein’s test
What is the one branch of the median nerve that does not pass through the carpal tunnel?
Palmar cutaneous branch of median nerve
What is the primary nerve supplying the thenar intrinsic muscles?
Recurrent branch of median nerve
What is the nerve supplying the hypothenar intrinsic muscles?
Ulnar
What is a clinical sign of prolonged carpal tunnel syndrome?
Thenar wasting known as Simian ape hand
What are the attachments of the lumbrical muscles?
FDP tendon
Extensor hood
What is the action of the lumbricals?
Flex at MP
Extends at PIP/DIP
What is the innervation of the lumbricals?
Median AND ulnar nerve! Both sides
What do the dorsal interossei muscles do?
Abduct digits
PAD and DAB
What do the palmar interossei muscles do?
Adduction
Pad and Dab
What innervates the interossei muscles?
Ulnar
What is a Swan Neck deformity?
Laxity of the volar plate causes slippage of collateral ligaments: PIP hyper extension/DIP flexion
What is a Boutteniere Deformity?
Rupture of the central tendon, through which the PIP joint protrudes. Results in PIP flexion, DIP extension
What is a Mallet Deformity?
Extensor tendon laxity due to overstretching or rupture which results in decreased efficiency of the extensor hood. Results in inability to extend the DIP.
What is tenodesis?
The natural flexion of fingers from wrist extension
Is there any motor innervation in the hand of the radial nerve?
No! Just cutaneous
What is the floor of the anatomical snuff box?
Scaphoid