Wrist/Hand Flashcards
Wrist Complex
Radiocarpal joint
Midcarpal Joints
Flx: 65-85
Extt: 60-85
-biaxial
-control length-tension relationship in hand muscles
-grip
Radiocarpal Joint Structure
-radius and TFCC proximally
-scaphoid and latteral radius
-lunate and medial radius
-triquetum and TFCC
TFCC Attachments
-connected medially via dorsal and volar radioulnar lig
-connects distally to ECU tendon
Proximal Carpal Row
-scaphoid, lunate, triquetrum
-connected by scapholunate interossesous lig and lynotriquetral interosseous lig
-scapoid and lunate get 80% of axial load; tfcc 20%
-pisiform proximal but acts as sesamoid to increase MA for FCU
Ulna Length Functions
Short Ulna= ulnar negative variance; keinbock’s disease (necrosis of lunate after fratcure)
Long ulna= Ulnar positive variance; radial fracure; impingement of TFCC
FCU Wrist Exception
-does not provide stability to midcarpal dispite crossing RC joint
-attaches to 5th meta, pisiform, and hook of hamate
Midcarpal Joint Structure
Proximal row and Distal row of carpals
Volar Carpal Ligaments
-stronger/thicker
Extrinsic Lig: radio carpal and ulnocarpal complex
Intrinsic lig: Scapholunate interosseous lig and Lunotriquetral interosseous lig
Dorsal Carpal Ligaments
-thin/weaker
-taut with flx
Dorsal radiocarpal lig: radius to triquetrum
Dorsal intercarpal lig: horizontal from triquetrum
Capitate
-keystone of wrist
-biggest carpal
-attaches to: Scaphoid, lunate, trapezoid, hamate, 1, 2, 3rd metacarparls
Wrist Flexion
-65-85 ROM
-Proximal carpals flex, distal row and scaphoid move ant
Wrist Extension
-60-85 ROM
-functional 20
-distal carpals glide post, distal row and scaphoid move on lunate, scaphoid and lunate lock
Wrist Radial Dev
-20 ROM
-capals slide ulnarly
-flx of proximal
-ext of distal
Wrist Ulnar Dec
-30 ROM
-functional : 10
-carpals slide radially
-flx of distal
-ext of proximal
Closed Packed Wrist
-full extension
Loose Packed Wrist
-full flexion
DISI
-dorsal intercalated segmental instability
-scapholunate lig tears, triquetrum pulls lunate dorsally into ext
VISI
-ventral intercalatted segmental instability
-lunotriquetral lig tears, scaphoid pulls lunate ventrally into flx
Carpometatarsal Joint
-increases mobility from radial to ulnar
-2nd-4th: plane joints
-5th: saddle joint; 2 degrees
Proximal Arch of Hand
-formed by carpal bones
-fixed
Distal Arch of Hand
-formed by metacarpals
-mobile
Longitudinal Arch of Hand
-proximal to distal
-mobile
Metacarphalangeal Joint
-ROM increases radially to ulnarly
-convex metalcarpal and concave phalanges
-condyloid joint; 2 degrees
-volar plates: increases stability, reisist forces
Collateral Ligament Proper: top to bottom, taut in flx
Accessory Collatteral Lig: bottom to ant; taut in extension
Interphalangeal Joints
-synovial
-base of phalynx has 2 shallow concaves
