Unit 1: Lecture 15 Flashcards
The motions of pronation/supination are augmented by what motions AT the wrist?
- flexion/extension
- ulnar/radial deviation
Name the carpal bones
- Pisiform
- Triquetrum
- Hamate
- Capitate
- Scaphoid
- Trapezium
- Trapezoid
- Lunate
Which carpal bone is most often broken?
Scaphoid
Which carpal bone is most often dislocated?
Lunate
Where does the triangular fibrocartilage covering the distal radioulnar joint originate?
Styloid process of ulna
What type of joint is the radiocarpal?
Ellipsoidal
On either side of the hand (radial and ulnar), what are the two ligaments connecting to the carpals?
Ulnar and radial collateral ligaments
What type of joints are the intercarpals?
Plane/gliding
Which joint capsule encloses an articular disk?
Distal Radioulnar joint
What motion do the radio/ulnar collateral ligaments limit?
Radio/ulnar deviation
Joints of the of the proximal carpal row
Joints between scaphoid, lunate, triquetrum, and pisiform
Joints of the of the distal carpal row
Joints between capitate, hamate, trapezoid, and trapezium
Midcarpal joints
Joints between proximal and distal rows
What’s to note about the pisiform?
- Forms the attachment of the flexor and extensor retinaculum on the ulnar side of the wrist
- The ulnar nerve passes between it and the hamate as it enters the palm, creating the Guyon’s Canal
What is the second most broken carpal bone?
Triquetrum
What is the third most broken carpal bone?
Trapezium
What kind of joints are the carpometacarpals (2-5)?
Gliding/plane
What kind of joint is the carpometacarpal of the thumb?
Saddle
What kind of joints are the metacarpal joints (2-5)?
Condyloid
What kind of joint is the MCP of the thumb?
Hinge
Deep transverse metacarpal ligament
Thick ligamentous band interconnecting the 2nd - 5th MCP joints
Keeps them from “overspreading”
Palmar ligament (plate)
The palmar/volar portion of the joint capsule, thickened with fibrocartilage
Collateral ligaments
- encase MCP, PIP, and DIPs
- tight during flexion; loose in extension to allow for ABduction/ADduction
Palmar aponeurosis
Triangular expansion of the palmar fascia covering the carpal tunnel and extending to the MCP joints
Thenar/Hypothenar Muscle Sheathes
Covers thenar/hypothenar muscles
Flexor retinaculum
- covers carpal tunnels
- connects thenar and hypothenar eminences
- originates from trapezium and inserts on hook of hamate
Intrinsic muscles of the hand
- Thenar muscles
- Hypothenar muscles
- Middle compartment muscles
Hypothenar muscles
Originate at flexor retinaculum or pisiform bone, act of 5th digit, and innervated by deep branch of ulnar nerve
- Abductor Digiti Minimi
- Flexor Digiti Minimi
- Opponens Digiti Minimi
Thenar muscles
Originate at carpal bone, flexor retinaculum, or the metacarpal bones – act on the thumb – and most are innervated by recurrent branch of median nerve
- Abductor pollicis brevis
- Flexor pollicis brevis
- Opponens pollicis
- Adductor pollicis (deep branch of ULNAR n.)
Middle compartment muscles of hand
Originate between 2-5 metacarpals and act on the same digits
- Interossii muscles (4 dorsal, 4 palmar - all deep branch of ULNAR n.)
- Lateral 2 lumbricals (median n.)
- Medial 2 lumbricals (deep branch of ulnar n.)
Ulnar artery crosses wrist…
Ulnar artery travels with…
DEEP to palmar aponeurosis, but SUPERFICIAL to flexor retinaculum
Ulnar nerve
What is the primary blood supply to the hand?
Ulnar nerve
Princeps pollicis artery (thumb) and radialis indicis artery (index finger) arise from what artery?
Radial artery
From where does the recurrent radial artery first arise?
Superior margin of the supinator muscle
Canal of Frohse
The canal the deep radial nerve passes through before it enters forearm
What passes THROUGH carpal tunnel?
- Median nerve
- Flexor Digitorum superficialis tendons (all 4)
- Flexor Digitorum profundus tendons (all 4)
- Flexor Pollicuc Longus tendon
Extensor Retinaculum: Compartment 1 structures
Abductor pollicis longus
Extensor pollicis brevis
Extensor Retinaculum: Compartment 2 structures
Extensor carpi radialis brevis
Extensor carpi radialis longus
Extensor Retinaculum: Compartment 3 structures
Extensor pollicis longus
Extensor Retinaculum: Compartment 4 structures
Extensor digitorum (pre-split) Extensor indicis
Extensor Retinaculum: Compartment 5 structures
Extensor digiti minimi
Extensor Retinaculum: Compartment 6 structures
Extensor carpi ulnaris
