ABOS Surgery of the Hand cheat sheet

Scaphoid fractures: anatomic snout tenderness; proximal pole has retrograde blood supply and highest avascular necrosis risk; MRI or CT detects occult fracture; nondisplaced waist fractures may be casted or percutaneously screwed.

Bennett fracture: intra-articular thumb metacarpal base fracture; the volar ulnar fragment remains attached to the anterior oblique ligament while the shaft is pulled radially and dorsally by abductor pollicis longus.

Rolando fracture: comminuted intra-articular fracture of the thumb metacarpal base; treatment usually requires open reduction and internal fixation or external fixation.

Colles fracture has dorsal angulation of the distal radius; Smith fracture has volar angulation; both require assessment of median nerve function, distal radioulnar joint, and ulnar styloid injury.

Mallet finger is a terminal extensor avulsion treated with continuous DIP extension splinting for 6 to 8 weeks; jersey finger is an FDP avulsion with inability to flex the DIP and requires surgical repair.

Flexor tendon zone II extends between the A1 pulley and FDS insertion; repair uses a core suture plus epitendinous suture with protected early motion to limit adhesions.

Median nerve injury causes thenar atrophy and loss of thumb opposition; ulnar nerve injury causes Froment sign, clawing, and intrinsic wasting; radial nerve injury causes wrist drop.

Compartment delta pressure equals diastolic blood pressure minus compartment pressure; a value below 30 mmHg supports compartment syndrome and fasciotomy.

Simple syndactyly is usually released at 12 to 18 months; border-digit syndactyly may be released earlier, and adjacent sides of the same digit are not operated simultaneously.

Radial polydactyly is graded by the Wassel classification I to VII according to duplication level; reconstruction preserves the ulnar collateral ligament and avoids zigzag deformity.

Pediatric trigger thumb presents as fixed interphalangeal flexion from a notched A1 pulley; observation is reasonable until about one year, then A1 pulley release is performed if persistent.

Blauth thumb hypoplasia grades I to V; grades IIIB, IV, and V have an unstable or absent carpometacarpal joint and are treated with index pollicization.

Radial longitudinal deficiency warrants evaluation for VACTERL anomalies, including cardiac, renal, vertebral, anal, and tracheoesophageal defects; thumb hypoplasia is common.

Salter-Harris classification: I physis only, II physis and metaphysis, III physis and epiphysis, IV physis, metaphysis, and epiphysis, V crush injury; type II is most common.

Seymour fracture is a distal phalanx physeal fracture with nail-bed laceration; it is an open fracture requiring nail removal, nail-bed repair, reduction, and splinting.

Camptodactyly is a PIP flexion contracture, often of the small finger; clinodactyly is radial angulation of the small finger from a delta middle phalanx.

Thumb carpometacarpal osteoarthritis is staged by Eaton I to IV; early stages are treated with splinting or injection, while advanced stages may require trapeziectomy with ligament reconstruction or arthrodesis.

Rheumatoid arthritis causes MCP ulnar drift and volar subluxation; extensor tendon rupture often occurs over the distal ulna and requires synovectomy, Darrach procedure, or tendon transfer.

Dupuytren disease produces pretendinous cords and a positive tabletop test; treatment options include collagenase injection and fasciectomy, with risk to digital neurovascular structures.

Gout crystals are needle-shaped monosodium urate crystals with negative birefringence; calcium pyrophosphate deposition disease crystals are rhomboid and positively birefringent.

SLAC and SNAC wrists develop progressive arthritis after scapholunate ligament injury or scaphoid nonunion; four-corner fusion or proximal row carpectomy is used for advanced stages.

Psoriatic arthritis commonly involves DIP joints, nail pitting, and dactylitis; rheumatoid arthritis typically spares DIP joints and involves MCP and PIP joints.

Mucous cyst is a dorsal DIP ganglion that may cause nail ridging; Heberden nodes occur at DIP joints and Bouchard nodes at PIP joints in osteoarthritis.

Carpal boss is a dorsal prominence over the second or third carpometacarpal joint; it must be differentiated from a ganglion and is usually treated conservatively.

Carpal tunnel release divides the transverse carpal ligament to decompress the median nerve; the recurrent motor branch and superficial palmar arch must be protected.

Cubital tunnel syndrome affects the ulnar nerve at the elbow; in-situ decompression or anterior transposition is used, especially with nerve subluxation or failed decompression.

Guyon canal contains the ulnar nerve and ulnar artery at the wrist; compression can cause intrinsic wasting and sensory loss, while the dorsal ulnar cutaneous nerve is spared.

Wartenberg syndrome is compression of the superficial radial nerve in the distal forearm; it causes dorsoradial wrist pain and dysesthesia without motor deficit.

Free flap monitoring uses color, capillary refill, temperature, and Doppler signals; congestion suggests venous thrombosis, pallor suggests arterial thrombosis, and both require urgent reexploration.

Nerve repair is tension-free epineurial repair for sharp lacerations; nerve graft is used for larger gaps, and conduit is reserved for short distal sensory gaps under about 3 cm.

Replantation is strongly indicated for thumb, multiple-digit, wrist-level, and pediatric amputations; clean-cut ischemia and proper cooling improve survival.

Z-plasty lengthens scar and changes its orientation; rhomboid flaps cover small defects; skin grafts require a vascular bed, while flaps cover exposed tendon or bone.

Most dorsal wrist ganglions arise from the scapholunate ligament; aspiration or excision is performed, and recurrence is more common after aspiration.

Enchondroma is a benign cartilaginous bone tumor common in the hand; it appears lytic with calcification, may cause pathologic fracture, and is treated by curettage with bone grafting.

Giant cell tumor of tendon sheath is a benign, firm volar digital nodule; excision is the treatment, and local recurrence is common because of incomplete removal.

Glomus tumor is a painful subungual lesion with cold sensitivity; MRI may help localize it, and excision provides relief.

Kanavel signs of flexor tenosynovitis are fusiform swelling, flexed posture, tenderness along the sheath, and pain with passive extension; treatment is irrigation and antibiotics.

Fight bite is a human bite over the metacarpophalangeal joint; oral flora including Eikenella corrodens can infect tendon or joint, requiring irrigation, antibiotics, and careful exploration.

Kienbock disease is avascular necrosis of the lunate, associated with ulnar-negative variance; MRI detects early disease, and treatment depends on stage and includes grafting, proximal row carpectomy, or fusion.

De Quervain tenosynovitis involves the first dorsal compartment at the radial styloid; trigger finger is A1 pulley stenosis with painful clicking and is treated by steroid injection or pulley release.

Scaphoid fractures: anatomic snout tenderness; proximal pole has retrograde blood supply and highest avascular necrosis risk; MRI or CT detects occult fracture; nondisplaced waist fractures may be casted or percutaneously screwed.

Bennett fracture: intra-articular thumb metacarpal base fracture; the volar ulnar fragment remains attached to the anterior oblique ligament while the shaft is pulled radially and dorsally by abductor pollicis longus.

Rolando fracture: comminuted intra-articular fracture of the thumb metacarpal base; treatment usually requires open reduction and internal fixation or external fixation.

Colles fracture has dorsal angulation of the distal radius; Smith fracture has volar angulation; both require assessment of median nerve function, distal radioulnar joint, and ulnar styloid injury.

Mallet finger is a terminal extensor avulsion treated with continuous DIP extension splinting for 6 to 8 weeks; jersey finger is an FDP avulsion with inability to flex the DIP and requires surgical repair.

Flexor tendon zone II extends between the A1 pulley and FDS insertion; repair uses a core suture plus epitendinous suture with protected early motion to limit adhesions.

Median nerve injury causes thenar atrophy and loss of thumb opposition; ulnar nerve injury causes Froment sign, clawing, and intrinsic wasting; radial nerve injury causes wrist drop.

Compartment delta pressure equals diastolic blood pressure minus compartment pressure; a value below 30 mmHg supports compartment syndrome and fasciotomy.

Simple syndactyly is usually released at 12 to 18 months; border-digit syndactyly may be released earlier, and adjacent sides of the same digit are not operated simultaneously.

Radial polydactyly is graded by the Wassel classification I to VII according to duplication level; reconstruction preserves the ulnar collateral ligament and avoids zigzag deformity.

Pediatric trigger thumb presents as fixed interphalangeal flexion from a notched A1 pulley; observation is reasonable until about one year, then A1 pulley release is performed if persistent.

Blauth thumb hypoplasia grades I to V; grades IIIB, IV, and V have an unstable or absent carpometacarpal joint and are treated with index pollicization.

Radial longitudinal deficiency warrants evaluation for VACTERL anomalies, including cardiac, renal, vertebral, anal, and tracheoesophageal defects; thumb hypoplasia is common.

Salter-Harris classification: I physis only, II physis and metaphysis, III physis and epiphysis, IV physis, metaphysis, and epiphysis, V crush injury; type II is most common.

Seymour fracture is a distal phalanx physeal fracture with nail-bed laceration; it is an open fracture requiring nail removal, nail-bed repair, reduction, and splinting.

Camptodactyly is a PIP flexion contracture, often of the small finger; clinodactyly is radial angulation of the small finger from a delta middle phalanx.

Thumb carpometacarpal osteoarthritis is staged by Eaton I to IV; early stages are treated with splinting or injection, while advanced stages may require trapeziectomy with ligament reconstruction or arthrodesis.

Rheumatoid arthritis causes MCP ulnar drift and volar subluxation; extensor tendon rupture often occurs over the distal ulna and requires synovectomy, Darrach procedure, or tendon transfer.

Dupuytren disease produces pretendinous cords and a positive tabletop test; treatment options include collagenase injection and fasciectomy, with risk to digital neurovascular structures.

Gout crystals are needle-shaped monosodium urate crystals with negative birefringence; calcium pyrophosphate deposition disease crystals are rhomboid and positively birefringent.

SLAC and SNAC wrists develop progressive arthritis after scapholunate ligament injury or scaphoid nonunion; four-corner fusion or proximal row carpectomy is used for advanced stages.

Psoriatic arthritis commonly involves DIP joints, nail pitting, and dactylitis; rheumatoid arthritis typically spares DIP joints and involves MCP and PIP joints.

Mucous cyst is a dorsal DIP ganglion that may cause nail ridging; Heberden nodes occur at DIP joints and Bouchard nodes at PIP joints in osteoarthritis.

Carpal boss is a dorsal prominence over the second or third carpometacarpal joint; it must be differentiated from a ganglion and is usually treated conservatively.

Carpal tunnel release divides the transverse carpal ligament to decompress the median nerve; the recurrent motor branch and superficial palmar arch must be protected.

Cubital tunnel syndrome affects the ulnar nerve at the elbow; in-situ decompression or anterior transposition is used, especially with nerve subluxation or failed decompression.

Guyon canal contains the ulnar nerve and ulnar artery at the wrist; compression can cause intrinsic wasting and sensory loss, while the dorsal ulnar cutaneous nerve is spared.

Wartenberg syndrome is compression of the superficial radial nerve in the distal forearm; it causes dorsoradial wrist pain and dysesthesia without motor deficit.

Free flap monitoring uses color, capillary refill, temperature, and Doppler signals; congestion suggests venous thrombosis, pallor suggests arterial thrombosis, and both require urgent reexploration.

Nerve repair is tension-free epineurial repair for sharp lacerations; nerve graft is used for larger gaps, and conduit is reserved for short distal sensory gaps under about 3 cm.

Replantation is strongly indicated for thumb, multiple-digit, wrist-level, and pediatric amputations; clean-cut ischemia and proper cooling improve survival.

Z-plasty lengthens scar and changes its orientation; rhomboid flaps cover small defects; skin grafts require a vascular bed, while flaps cover exposed tendon or bone.

Most dorsal wrist ganglions arise from the scapholunate ligament; aspiration or excision is performed, and recurrence is more common after aspiration.

Enchondroma is a benign cartilaginous bone tumor common in the hand; it appears lytic with calcification, may cause pathologic fracture, and is treated by curettage with bone grafting.

Giant cell tumor of tendon sheath is a benign, firm volar digital nodule; excision is the treatment, and local recurrence is common because of incomplete removal.

Glomus tumor is a painful subungual lesion with cold sensitivity; MRI may help localize it, and excision provides relief.

Kanavel signs of flexor tenosynovitis are fusiform swelling, flexed posture, tenderness along the sheath, and pain with passive extension; treatment is irrigation and antibiotics.

Fight bite is a human bite over the metacarpophalangeal joint; oral flora including Eikenella corrodens can infect tendon or joint, requiring irrigation, antibiotics, and careful exploration.

Kienbock disease is avascular necrosis of the lunate, associated with ulnar-negative variance; MRI detects early disease, and treatment depends on stage and includes grafting, proximal row carpectomy, or fusion.

De Quervain tenosynovitis involves the first dorsal compartment at the radial styloid; trigger finger is A1 pulley stenosis with painful clicking and is treated by steroid injection or pulley release.

Scaphoid fractures: anatomic snout tenderness; proximal pole has retrograde blood supply and highest avascular necrosis risk; MRI or CT detects occult fracture; nondisplaced waist fractures may be casted or percutaneously screwed.

Bennett fracture: intra-articular thumb metacarpal base fracture; the volar ulnar fragment remains attached to the anterior oblique ligament while the shaft is pulled radially and dorsally by abductor pollicis longus.

Rolando fracture: comminuted intra-articular fracture of the thumb metacarpal base; treatment usually requires open reduction and internal fixation or external fixation.

Colles fracture has dorsal angulation of the distal radius; Smith fracture has volar angulation; both require assessment of median nerve function, distal radioulnar joint, and ulnar styloid injury.

Mallet finger is a terminal extensor avulsion treated with continuous DIP extension splinting for 6 to 8 weeks; jersey finger is an FDP avulsion with inability to flex the DIP and requires surgical repair.

Flexor tendon zone II extends between the A1 pulley and FDS insertion; repair uses a core suture plus epitendinous suture with protected early motion to limit adhesions.

Median nerve injury causes thenar atrophy and loss of thumb opposition; ulnar nerve injury causes Froment sign, clawing, and intrinsic wasting; radial nerve injury causes wrist drop.

Compartment delta pressure equals diastolic blood pressure minus compartment pressure; a value below 30 mmHg supports compartment syndrome and fasciotomy.

Simple syndactyly is usually released at 12 to 18 months; border-digit syndactyly may be released earlier, and adjacent sides of the same digit are not operated simultaneously.

Radial polydactyly is graded by the Wassel classification I to VII according to duplication level; reconstruction preserves the ulnar collateral ligament and avoids zigzag deformity.

Pediatric trigger thumb presents as fixed interphalangeal flexion from a notched A1 pulley; observation is reasonable until about one year, then A1 pulley release is performed if persistent.

Blauth thumb hypoplasia grades I to V; grades IIIB, IV, and V have an unstable or absent carpometacarpal joint and are treated with index pollicization.

Radial longitudinal deficiency warrants evaluation for VACTERL anomalies, including cardiac, renal, vertebral, anal, and tracheoesophageal defects; thumb hypoplasia is common.

Salter-Harris classification: I physis only, II physis and metaphysis, III physis and epiphysis, IV physis, metaphysis, and epiphysis, V crush injury; type II is most common.

Seymour fracture is a distal phalanx physeal fracture with nail-bed laceration; it is an open fracture requiring nail removal, nail-bed repair, reduction, and splinting.

Camptodactyly is a PIP flexion contracture, often of the small finger; clinodactyly is radial angulation of the small finger from a delta middle phalanx.

Thumb carpometacarpal osteoarthritis is staged by Eaton I to IV; early stages are treated with splinting or injection, while advanced stages may require trapeziectomy with ligament reconstruction or arthrodesis.

Rheumatoid arthritis causes MCP ulnar drift and volar subluxation; extensor tendon rupture often occurs over the distal ulna and requires synovectomy, Darrach procedure, or tendon transfer.

Dupuytren disease produces pretendinous cords and a positive tabletop test; treatment options include collagenase injection and fasciectomy, with risk to digital neurovascular structures.

Gout crystals are needle-shaped monosodium urate crystals with negative birefringence; calcium pyrophosphate deposition disease crystals are rhomboid and positively birefringent.

SLAC and SNAC wrists develop progressive arthritis after scapholunate ligament injury or scaphoid nonunion; four-corner fusion or proximal row carpectomy is used for advanced stages.

Psoriatic arthritis commonly involves DIP joints, nail pitting, and dactylitis; rheumatoid arthritis typically spares DIP joints and involves MCP and PIP joints.

Mucous cyst is a dorsal DIP ganglion that may cause nail ridging; Heberden nodes occur at DIP joints and Bouchard nodes at PIP joints in osteoarthritis.

Carpal boss is a dorsal prominence over the second or third carpometacarpal joint; it must be differentiated from a ganglion and is usually treated conservatively.

Carpal tunnel release divides the transverse carpal ligament to decompress the median nerve; the recurrent motor branch and superficial palmar arch must be protected.

Cubital tunnel syndrome affects the ulnar nerve at the elbow; in-situ decompression or anterior transposition is used, especially with nerve subluxation or failed decompression.

Guyon canal contains the ulnar nerve and ulnar artery at the wrist; compression can cause intrinsic wasting and sensory loss, while the dorsal ulnar cutaneous nerve is spared.

Wartenberg syndrome is compression of the superficial radial nerve in the distal forearm; it causes dorsoradial wrist pain and dysesthesia without motor deficit.

Free flap monitoring uses color, capillary refill, temperature, and Doppler signals; congestion suggests venous thrombosis, pallor suggests arterial thrombosis, and both require urgent reexploration.

Nerve repair is tension-free epineurial repair for sharp lacerations; nerve graft is used for larger gaps, and conduit is reserved for short distal sensory gaps under about 3 cm.

Replantation is strongly indicated for thumb, multiple-digit, wrist-level, and pediatric amputations; clean-cut ischemia and proper cooling improve survival.

Z-plasty lengthens scar and changes its orientation; rhomboid flaps cover small defects; skin grafts require a vascular bed, while flaps cover exposed tendon or bone.

Most dorsal wrist ganglions arise from the scapholunate ligament; aspiration or excision is performed, and recurrence is more common after aspiration.

Enchondroma is a benign cartilaginous bone tumor common in the hand; it appears lytic with calcification, may cause pathologic fracture, and is treated by curettage with bone grafting.

Giant cell tumor of tendon sheath is a benign, firm volar digital nodule; excision is the treatment, and local recurrence is common because of incomplete removal.

Glomus tumor is a painful subungual lesion with cold sensitivity; MRI may help localize it, and excision provides relief.

Kanavel signs of flexor tenosynovitis are fusiform swelling, flexed posture, tenderness along the sheath, and pain with passive extension; treatment is irrigation and antibiotics.

Fight bite is a human bite over the metacarpophalangeal joint; oral flora including Eikenella corrodens can infect tendon or joint, requiring irrigation, antibiotics, and careful exploration.

Kienbock disease is avascular necrosis of the lunate, associated with ulnar-negative variance; MRI detects early disease, and treatment depends on stage and includes grafting, proximal row carpectomy, or fusion.

De Quervain tenosynovitis involves the first dorsal compartment at the radial styloid; trigger finger is A1 pulley stenosis with painful clicking and is treated by steroid injection or pulley release.