Hand Flashcards
Thenar muscles (4)
Abductor Pol Brev
Opponens Pol
Flexor pol brev
Adductor pol
Hypothenar muscles (4)
Palmaris Brevis
Abductor digiti minimi
Flexor digiti minimi brevis
Opponens digiti minimi
Intrinsic hand muscles (3)
Lumbricals
Dorsal interosseous
Volatile interosseous
1st dorsal compartment (2)
Abductor pollicis longus
Extensor pollicis brevis
2nd dorsal compartment (2)
Extensor carpi radialis longus (ECRL)
Extensor carpi radialis brevis (ECRB)
3rd dorsal compartment (1)
Extensor pollicis longus (EPL)
4th dorsal compartment (2)
Extensor digitorum communis (EDC)
Extensor indicis propius (EIP)
5th dorsal compartment (1)
Extensor digiti minimi (EDM)
6th dorsal compartment (1)
Extensor carpi ulnaris (ECU)
1DC: Anatomic considerations (2)
EPB tendon is ulnar to abductor PL (APL)
APL may have multiple tendon slips, which should be addressed for release of…
1DC pathology
Duquervain tenosynovitis
2DC pathology
Extensor tendinitis (intersection syndrome)
3DC pathology (2)
EPL rupture at Lister’s after wrist fx
Drummer’s tendinitis of the wrist
4DC pathology
Extensor tenosynovitis
5DC pathology
Vaughn-Jackson syndrome (RA; rupture of EDM)
6DC pathology
Snapping at ulnar styloid
Abd pol brev
Origin
Insertion
Action
Innervation
Origin: Scahpoid, trapezoid
Insertion: base of proximal phalanx, radial side
Action: abducts thumb
Innervation: median nerve
Opponens pollicis
Origin
Insertion
Action
Innervation
Origin: trapezium
Insertion: thumb metacarpal
Action: abduction, flexion, medial rotation
Innervation: median nerve
Flexor pollicis brevis
Origin
Insertion
Action
Innervation
Origin: Trapezium, capitate
Insertion: base of thumb P1, radial side
Action: thumb MCP flexion
Innervation: median, ulnar
Adductor pollicis
Origin
Insertion
Action
Innervation
Origin: Capitate, second/third metacarpals
Insertion: base of thumb P1, ulnar side
Action: adduct thumb
Innervation: ulnar nerve
Palmaris brevis
Origin
Insertion
Action
Innervation
Origin: TCL, palmar aponeurosis
Insertion: ulnar palm
Action: retract skin
Innervation: ulnar nerve
Abductor digiti minimi
Origin
Insertion
Action
Innervation
Origin: Pisiform
Insertion: base of SF P1, ulnar side
Action: abduct SF
Innervation: ulnar nerve
Flexor digiti minimi brevis
Origin
Insertion
Action
Innervation
Origin: Hamate, TCL
Insertion: Base of SF P1, ulnar side
Action: Flex SF MCP
Innervation: Ulnar nerve
“Hand” muscles are grouped into (3)
Thenar
Hypothenar
Intrinsic
Opponens digiti minimi
Origin
Insertion
Action
Innervation
Origin: Hamate, TCL
Insertion: SF MC
Action: Abduct, flex, rotate laterally
Innervation: Ulnar nerve
Lumbricals
Origin
Insertion
Action
Innervation
Origin: Flexor digitorum profundus
Insertion: Lateral bands (radial)
Action: PIP extension
Innervation: median and ulnar nerves
Dorsal and volar interossei
Origin
Insertion
Action
Innervation
Origin: Adjacent metacarpals
Insertion: base of P1/extensor apparatus
Action: Volar: adduction and MCP flexion, Dorsal: abduction and MCP flexion
Innervation: Ulnar nerve
Four components of hand extensor mechanism
Saggital bands
Transverse bands
Lateral bands
Oblique retinacular ligament (Landsmeer)
Saggital bands
Attachments
Significance
Attachments: Covers MCP joint
Significance: Allows MCP extension
Transverse ligament of extensor apparatus
Attachments
Significance
Attachments: Volar plate fibers
Significance: Allows MCP flexion (interossei)
Lateral bands
Attachments
Significance
Attachments: Covers PIP
Significance: allows PIP extension (Lumbricals)
Oblique retinacular ligament (Landsmeer)
Attachments
Significance
Attachments: A4 pulley, terminal tendon
Significance: Allows DIP extension (passive)
Carpal tunnel borders (4)
Roof
Floor
Radial
Ulnar
Roof: TCL
Floor: Carpal bones
Radial: Scaphoid tubercle/trapezium
Ulnar: Hook of hamate
5 Superficial flexors, innervation?
PT
PL
FCR
FCU
FDS
All median nerve except FCU (ulnar)
3 Deep flexors, innervation?
FDP
FPL
PQ
AIN
7 Superficial extensors
Anconeus
BR
ECU
ECR L
ECR B
ED
EDM
5 Deep extensors, innervation?
Supinator
Abductor pollicis longus
Extensor pollicis longus
Extensor pollicis brevis
Extensor indicis proprius
ALL PIN