Upper Extremity Week 3 Learning Objectives Flashcards
Identify the joints of the wrist and hand and provide their synovial classification on the Structure Information List.
Distal radio-ulnar
synovial classification- pivot or trochoid
Radiocarpal
synovial classification- ellipsoidal or condyloid (forward/back, side to side)
Carpometacarpal
- First (thumb)
synovial classification- sellar or saddle
- 2nd-5th (index, middle, ring, little)
synovial classification- plane or gliding
Metacarpophalangeal
synovial classification- ellipsoidal or condyloid
Interphalangeal
synovial classification- ginglymus or hinge
Identify the functions and attachments of the ligaments of the wrist and hand on the Structure Information List.
Transverse carpal:
function- prevents bowstringing of the tendons of the flexor pollicis longus, flexor digitorum superficialis & flexor digitorum profundus muscles
attachments- from the pisiform & hook of the hamate to scaphoid & trapezium
Collateral ligaments of the metacarpophalangeal joints:
function- stabilizes metacarpophalangeal joints
attachments- from the head of the metacarpals to base of adjacent proximal phalanx (on each side of joint)
Locate the surface features of the wrist and hand.
Pulp - tip of the finger
Distal digital crease - b/t distal and middle phalanges
Middle digital crease - b/t middle and proximal phalanges
Proximal digital crease - b/t proximal and metacarpal phalanges
Distal palmar crease - line just below MCP joint, originating from ulnar side of palm
Proximal palmar crease - line just below distal palmar crease, through middle of palm
Web space - b/t thumb and second digit
Thenar crease - curving line separating thenar eminence
Thenar eminence - padded space above first metacarpal
Hypothenar eminence - padded space above fifth metacarpal
Distal wrist crease - line just below palm
Proximal wrist crease - line just below distal wrist crease
Describe the carpal bones including their organization into proximal and distal rows.
Proximal carpal row (radial to ulnar): scaphoid (navicular), lunate, triquetrum, pisiform
Distal carpal row (radial to ulnar): trapezium, trapezoid, capitate, hamate
Name and demonstrate the actions (motions) available at the wrist.
Flexion
Extension
Radial deviation
Ulnar deviation
Name the ligaments of the wrist and what actions (motions) they restrict.
Radius to ulna: restricts pronation/supination
Radius to carpals: restricts ulnar deviation
Ulna to carpals: restricts radial deviation
Carpals to carpals: stabilize
ADD ACTIONS
Describe the attachments and functions of the transverse carpal ligament (flexor retinaculum).
Attachments:
Ulnar - Hook of Hamate & Pisiform
Radial - Trapezium & Scaphoid
Functions:
- Attachment for thenar & hypothenar muscles
- Maintains carpal arch
- Prevents bowstringing of flexor tendons
- Protects median nerve
Describe the structure and function of the triangular fibrocartilage complex (TFCC).
Articular disc primary structure:
- Triangular in shape
- Analogous to meniscus in knee
- Shock Absorption
- Fibrocartilage (Degenerate with overuse and aging)
Dorsal/volar radioulnar ligaments Ulnar collateral ligament ECU sheath Ulnotriquetral ligament Ulnolunate ligament
Name the compartments formed by the extensor retinaculum and the tendons found within each.
1: Abductor Pollicis Longus (APL), Extensor Pollicis Brevis (EPB)
2: Extensor Carpi Radialis Longus/Brevis (ECRL/B)
3: Extensor Pollicis Longus (EPL)
4: Extensor Digitorum (ED), Extensor Indicis (EI)
5: Extensor Digiti Minimi (EDM)
6: Extensor Carpi Ulnaris (ECU)
Name and demonstrate the actions (motions) of the fingers and thumb.
Finger MP Joints:
Abduct/ Adduct
Flex/Extend
Rotate (Conjunct)
Finger PIP/DIP Joints:
Flex/Extend
Thumb CMC Joint:
ABD/ADD - sagittal plane
Flex/ext - frontal plane
Thumb MP Joint:
Flexion
Extension
Thumb IP Joint:
Flexion
Extension
Describe the structure of the palmar fascia and palmar digital sheaths.
Continuous with antebrachial fascia
Thenar fascia
Hypothenar fascia
Palmar aponeurosis
Palmar (Fibrous) Digital Sheaths - Pulleys
Fingers/ Thumb:
- Annular: straight (A1-A5)
- Cruciate: crossed (C1-C3)
Function:
Maintain relationship of flexor tendons to bone
Prevent bowstringing of tendons
A2 & A4 most critical
Describe the structure and function of the juncturae tendinae.
Intertendinous connections of Extensor Digitorum (ED)
- Distributes forces
- Number & location varies between & among individuals
Differentiate between muscles that are found in the forearm (extrinsic) and the hand (intrinsic).
Intrinsic muscles (originate & insert in hand): Thenar Hypothenar Adductor pollicis Lumbricals Interossei
Extrinsic (originate in forearm & insert in hand): Flexor digitorum profundus (FDP) Flexor digitorum superficialis (FDS) Flexor pollicis longus (FPL) Abductor pollicis longus (APL) Extensor pollicis longus (EPL) Extensor digitorum (ED) Extensor Indicis (EI) Extensor digiti minimi (EDM)
Describe the location and function of the ligaments of the fingers (phalanges).
Radial/Ulnar Collateral (provides radial/ ulnar stability): Proximal attachment: dorsal surface Distal attachment: volar surface - taut in flexion (lengthens) - lax in extension (shortens)
Volar plate (prevents finger hyperextension): Palmar ligament
Explain what muscles that attach to the extensor mechanism/expansion/hood and how they move the finger because of this attachment.
Extensor Hood:
- Complex tendon covering dorsal aspect of digits
- Cable system that extends MPs & IPs
- Allows lumbricals & interossei to assist in MP flexion
Muscles:
Extensor Digitorum
Lumbricals
Interossei
*CHECK
