Hand and Microvascular
Core concepts
Hand surgery rewards anatomic and functional reasoning. Know the flexor tendon zones, the pulley system, and the principles of tendon repair (core suture plus epitendinous repair, early controlled motion). Understand the intrinsic muscles and their innervation, and the patterns of nerve injury (median, ulnar, radial) including the claw hand and ape hand. Master the vascular anatomy of the hand (radial and ulnar contributions to the superficial and deep palmar arches) and the Allen test. Review common compressive neuropathies (carpal tunnel, cubital tunnel) and their electrodiagnostic and surgical indications. Know the principles of microsurgery: vessel size, end-to-end vs end-to-side anastomosis, vein grafts, and the timing of replantation. Also cover common fractures (scaphoid, distal radius, phalanges) and their complications (nonunion, malunion, CRPS).
Traps
Examiners test the scaphoid: a negative initial film does not exclude fracture, and proximal pole fractures have a high nonunion risk due to retrograde blood supply. Another trap is confusing median and ulnar nerve territories in the hand, and missing a concomitant tendon or nerve injury in a laceration.
Rule of thumb
In any hand laceration, assume a nerve or tendon injury until proven otherwise, and document two-point discrimination and motor function before and after treatment.
Worked example
A fall on an outstretched hand with snuffbox tenderness but a normal radiograph: treat as a scaphoid fracture, immobilize, and repeat imaging or obtain MRI; proximal pole fractures need aggressive management because of tenuous blood supply.