Hand Flashcards
Significance of proximal palmar crease?
Appx site of the superficial palmar arch
Significant of distal palmar crease?
site of MCP joints (dorsally)
Bennett’s fracture. Deforming force?
Base of thumb metacarpal fx (type 1): intraarticular fracture with proximal and radial dx of 1st metacarpal. Triangular bone fragments. APL deforms
Rolando fracture. Complications?
Base of thumb metacarpal fx (type 2): Intraarticular fracture with Y-shape. DJD after
Flexed fingers point to:
Tuberosity of scaphoid
Most common metacarpal fracture? Most common anatomic location?
5th MC Neck of MC
Boxer’s fracture?
Base of 5th MC
Gamekeeper’s thumb
Thumb MCP joint proper ulnar collateral ligament injury from forced radial deviation. Ski pole injury often. Stener lesion seen. Test at 30° flexion
Stenor lesion?
When adductor aponeurosis falls under torn ulnar collateral ligament, producing a palpable mass.
Mallet finger?
Rupture of the extensor tendon from distal phalanx. Bony avulsion from EDU seen.
Jersey finger?
FDP avulsion from P3 (avulsion fracture from volar base of P3)
Flexor tendon zones I-V and Thumb I-III
I: distal to FDS inertion II: Flexor retinaculum. No man’s land. avoid A2 and A4. III: Palm. IV: Carpal tunnel. Release and repair TCL during repair V: Wrist and forearm. Thumb I: Distal to FPL insertion Thumb II: Thumb flexor retinaculum. Preserve either A1 or oblique pulley Thumb III: Thenar eminence. Do not operate in this zone due to recurrent motor branch of median n
Extensor tendon zones I-IX
I: DIP joint. Mallet finger II: Middle phalanx III: PIP joint. Central slip injury. If triangular ligament is disrupted, lateral bands migrate volarly resulting in boutinniere finger. IV: Proximal phalanx V: MCP joint. Injury from fight bite. Repair tendon and sagittal bands as needed VI: Metacarpal. VII: Wrist VIII: Distal forearm. At MSC jxn IX: proximal forearm.
Draw flexor tendon sheath
A1 MCPJ, A2 proximal phalanx, A3 PIPJ, A4 middle phalanx, A5 DIPJ.
What can cause trigger finger?
Tight A1 ligament
Significance of Anterior oblique CMC ligament?
Ulnar side of 1st MC base to tubercle of trapezium. Beak ligament. Holds fragment in Bennett’s fx. Primary restraint to subluxation.
Significance of dorsal radial CMC ligament?
Dorsal trapezium to dorsal MC base. Strongest ligament. Torn in dorsal dx.
Cam effect in MC head and collateral ligament
Tight in flexion, loose in extension
Significance of Grayson’s ligament
Volar to neurovascular bundle, stabilizes skill in NV bundle.
Sig. of Cleland’s ligament
Dorsal to NV bundle. Stabilizes skin during flexion/extension.
Flexion and extension of MCP joint muscles
Flexion - IO muscles + lumbricals
Extension - extensor digitorum via sagittal bands