Wrist & Hand Flashcards
What are the muscles of the hand?
Intrinsic:
Thenar: Abductor pollicis brevis, flexor pollicis brevis, opponens pollicis brevis
Adductor pollicis
Hypothenar: opponens digiti minimi, flexor digiti minimi, abductor digiti minimi
Extrinsic: FDP, FDS, FPL, APL, EPL, ED, EI, EDM
Identify the joints of the hand and their synovial classification.
Proximal radioulnar - ellipsoidal Carpometacapral (CMC) - pivot Metacarpophalangeal (MP) -ellipsoidal Proximal Interphalangeal (PIP) - hinge Distal Interphalangeal (DIP) - hinge Interphalangeal (IP) of thumb - saddle
Identify the functions and attachments of the ligaments of the wrist and hand.
Wrist: Dorsal and palmar Radioulnar ligament Radial Collateral ligament Ulnar Collateral ligament Lunotriquetral, scapholunate ligament, etc.
Hand: Radial/Ulnar Collateral: MP, PIP, DIP Proximal attachment - dorsal surface Distal attachment - palmar surface Palmar ligament on palmar plate
Summarize collateral circulation at the hand.
See drawing
Locate surface features of the wrist and hand.
.
Describe the carpal bones.
Proximal Row: Scaphoid, Lunate, Triquetrum, Pisiform
Distal Row: Trapezium, Trapezoid, Capitate, Hamate
Name and demonstrate the actions (motions) at the wrist.
Flexion, Extension, Radial/Ulnar Deviation
Describe the attachments and functions of the transverse carpal ligament.
Portion of flexor retinaculum
Attachments:
Ulnar - hook of hamate and pisiform
Radial - trapezium and scaphoid
Functions: Attachment for thenar and Hypothenar muscles Maintains carpal arch Prevents bowstringing of flexor tendons Protects median n.
Describe the structure and function of the triangular fibrocartilage complex (TFCC).
Structure: Triangular in shape Analogous to meniscus in knee Shock absorption Fibrocartilage - degenerates over time Distal to ulna
Function: stabilizes ulna and carpals
Name the components formed by the extensor retinaculum and the tendons found within each.
APL, ECRL, ECRB, EPL, ED, EI, EDM, ECU
Function: helps create optimum line of pull for motions done with thumb
Name the bones of the hand.
Carpals, metacarpals, phalanges
Name the joints of the hand.
Carpometacarpal (CMC) Metacarpophalangeal (MP) Proximal interphalangeal (PIP) Distal interphalangeal (DIP) Interphalangeal (IP) of thumb
Name and demonstrate the actions (motions) of the fingers and thumb.
Finger
MP Joints: ab/adduction, flexion/extension, rotate (conjunct)
PIP/DIP Joints: flexion/extension
Thumb
CMC: radial ab/adduction, palmar ab/adduction, opposition/reposition
MP joint: flexion/extension
IP joint: flexion/extension
Describe the structure of the palmar fascia and digital fascia sheaths.
Palmar Fascia: continuous with antebrachial fascia, thenar fascia, Hypothenar fascia, palmar aponeurosis
Digital Fascia Sheaths: pulleys - anular: straight - cruciate: crossed Function: maintain relationship of flexor tendons to bone Prevent bowstringing of tendons
Describe the structure and function of the juncturae tendinae.
Structure: intertendinous connections of ED
Function: distributes forces between extensor tendons to prevent rupture
Differentiate between muscles that are found in the forearm (extrinsic) and the hand (intrinsic).
Extrinsic: FDP, FDS, FPL, APL, EPL, ED, EI, EDM
Intrinsic: Thenar (abductor pollicis brevis, flexor pollicis brevis, opponens pollicis brevis), adductor pollicis, Hypothenar (opponens digiti minimi, flexor digiti minimi, abductor digiti minimi)
Describe the location and function of the ligaments of the finger (phalanges).
Radial/Ulnar Collateral Ligament: MP, PIP, DIP
Proximal attachment - dorsal surface
Distal attachment - palmar surface
Function: taught in flexion (lengthens), lax in extension (shortens)
Explain what muscles attach to the extensor mechanism/expansion/hood and how they move the finger because of this attachment.
Attachments: ED, juncturae tendinae, transverse retinacular ligament, oblique retinacular ligament
Function: structures work together for extension of fingers
Review the peripheral nerve supply/distribution of the following nerves: radial, median, and ulnar.
Hand:
Median N.: thenar mm (recurrent branch), 1st & 2nd lumbricals
Ulnar N: Hypothenar mm, adductor pollicis, deep head flexor pollicis brevis, 3rd & 4th lumbricals, dorsal and palmar interossei
Radial N: none
Wrist:
Median N: anterior compartment and radial side of hand
Ulnar N: some thenar, all interossei, all Hypothenar, some lumbricals
Radial N: extensor supinator group - no muscles of hand
Name the boundaries and contents of the anatomical snuff box.
Boundaries:
Dorsal - EPL (3rd extensor compartment)
Palmar - APL & EPB (1st extensor compartment)
*Scaphoid is floor
Describe the underlying anatomy associated with carpal tunnel syndrome.
Median n. Compression at the wrist Transverse carpal ligament
Identify structures on Hypothenar Eminence level.
Kenhub
Describe sensory nerve distribution.
Radial N: dorsal surface of thumb and most of radial aspect of hand
Ulnar N: palmar and dorsal surface
Median N: palmar thumb and digits 2& 3, dorsal digits 2-4 tips
