Hand & Wrist Disorders

Stenosing tenosynovitis: de Quervain and trigger finger

de Quervain tenosynovitis. The abductor pollicis longus and extensor pollicis brevis share the first dorsal compartment over the radial styloid, and repetitive thumb and wrist motion thickens their sheath until gliding hurts. Pain and swelling sit over the radial styloid and worsen with pinching and lifting, so new mothers carrying infants are the classic patients. In the Finkelstein test the patient tucks the thumb into a fist and the examiner ulnar-deviates the wrist, reproducing the pain.

Treatment. NSAIDs, activity modification, and a forearm-based thumb spica splint come first; a corticosteroid injection into the first dorsal compartment is the most effective nonoperative treatment. Refractory cases undergo surgical release of the compartment, protecting the superficial radial nerve.

Trigger finger. In stenosing flexor tenosynovitis a thickened flexor tendon or tendon nodule catches at the A1 pulley over the metacarpal head. The finger clicks painfully or locks in flexion and may need to be pulled straight, and a tender nodule is felt at the distal palmar crease. The ring finger and thumb are most often affected. Diabetes, rheumatoid arthritis, and hypothyroidism predispose, and diabetics often have several trigger digits that respond less durably to injection. Treatment is splinting and corticosteroid injection into the tendon sheath, then percutaneous or open release of the A1 pulley for refractory or locked digits.

Dupuytren contracture and ganglion cysts

Dupuytren contracture. Myofibroblasts proliferate within the palmar fascia, producing painless nodules and then longitudinal cords that pull the MCP and PIP joints into flexion. The ring finger is affected first and the small finger next, often in both hands. Risk factors are older age, male sex, Northern European ancestry, family history, alcohol use, smoking, diabetes, and antiepileptic drugs. Related fibromatoses include plantar (Ledderhose), penile (Peyronie), and knuckle pads (Garrod).

Splinting does not halt progression. Nodules and mild cords are observed; once the palm cannot lie flat on a table (a positive tabletop test, roughly ≥30° of MCP contracture) or a PIP contracture develops, options are collagenase injection, percutaneous needle fasciotomy, or limited fasciectomy. Recurrence after any of them is common.

Ganglion cysts. The most common soft-tissue mass of the hand and wrist is a mucin-filled cyst arising from a joint capsule or tendon sheath, most often on the dorsal wrist over the scapholunate ligament, usually in young women. It is smooth, rubbery, transilluminates, and grows or shrinks with activity. Many resolve on their own, so observation is first-line; aspiration relieves symptoms but recurrence is frequent, and persistent symptomatic cysts are excised with their stalk. Volar wrist ganglia lie beside the radial artery, which makes aspiration there riskier.

Tendon and ligament injuries of the fingers and thumb

Mallet finger. A ball striking the tip of an extended finger forces the DIP into flexion and ruptures the terminal extensor tendon or avulses it with a fragment of the distal phalanx, so the fingertip droops and cannot be actively extended. Radiographs look for a bony fragment and volar subluxation. The DIP is splinted in extension continuously for 6–8 weeks with the PIP free, then at night; any flexion during that period restarts the clock. A large articular fragment with subluxation or an open injury needs surgery. Untreated, the imbalance produces a swan-neck deformity (PIP hyperextension, DIP flexion).

Jersey finger. Forced extension of a flexed finger, as when grabbing a jersey, avulses the flexor digitorum profundus from the distal phalanx, most often in the ring finger. When the examiner holds the PIP straight, the patient cannot flex the DIP. Because the tendon can retract into the palm and scar, surgical reattachment should happen early, ideally within about 1 week.

Skier's and gamekeeper's thumb. An acute fall on a ski pole, or chronic repetitive stress (gamekeeper's thumb), forces the thumb MCP into radial deviation and tears the ulnar collateral ligament. Stress testing is done in full extension and 30° of flexion; laxity beyond 30–35°, or 15° more than the other side, without a firm endpoint signals a complete tear. Partial tears heal in a thumb spica splint or cast for 4–6 weeks. Complete tears, displaced avulsion fractures, and Stener lesions, in which the adductor pollicis aponeurosis is trapped between the torn ligament and its insertion (sometimes felt as a lump), require surgical repair.

Obtain radiographs before stress-testing the thumb: an undisplaced avulsion fracture can be displaced by the maneuver.

Boxer's fracture and fight bites

Boxer's fracture. Punching a hard object breaks the neck of the 5th (sometimes 4th) metacarpal; the head tips toward the palm (apex-dorsal angulation), flattening the knuckle. PA, lateral, and oblique films define the fracture. The small finger tolerates more angulation than the radial digits, but rotational malalignment is never acceptable: when the patient makes a fist, the fingers should converge without overlapping, and scissoring requires reduction and fixation. Otherwise an ulnar gutter splint with the MCPs flexed is used.

A laceration over the knuckle after a punch is a fight bite until proven otherwise. Human oral flora, including Eikenella corrodens, is driven into the joint or tendon sheath: irrigate, explore, leave the wound open, update tetanus, and give amoxicillin-clavulanate.

Hand infections

Paronychia and felon. Acute paronychia is a staphylococcal or streptococcal infection of the lateral or proximal nail fold; an abscess is drained by lifting the fold. A felon is an abscess within the septated fat compartments of the fingertip pulp, usually S. aureus after a puncture. The closed space makes pain throbbing and the pad tense, and without incision and drainage (a lateral incision that spares the tactile pad) it can cause osteomyelitis of the distal phalanx, skin necrosis, or spread into the flexor sheath.

Herpetic whitlow. HSV inoculated into the fingertip causes burning pain and clustered vesicles on a red base while the pulp stays soft. PCR confirms it. Care is supportive, with oral acyclovir or valacyclovir if started early; incision invites bacterial superinfection and spread.

Pyogenic flexor tenosynovitis. A volar puncture seeds the closed flexor sheath, most often with S. aureus and next with streptococci; in sexually active patients, disseminated gonococcal infection can seed tendon sheaths hematogenously. The four Kanavel signs are fusiform (sausage) swelling of the digit, a finger held in slight flexion, pain with passive extension, and tenderness along the course of the sheath. Management is IV antibiotics covering staphylococci (including MRSA) and streptococci plus emergent surgical irrigation and drainage. Delay leads to tendon necrosis and adhesions, loss of the finger, or spread to the deep palmar spaces; because the thumb and small finger sheaths can communicate at the wrist, infection can spread between them as a horseshoe abscess.

High-pressure injection injury

Deceptively small. Paint, grease, solvents, or hydraulic fluid fired from a high-pressure gun, often into the nondominant index finger, leave only a pinpoint entry wound and little early pain. The material tracks along tendon sheaths and fascial planes far from the wound, provoking chemical inflammation, vascular compromise, and compartment syndrome. Amputation rates are high, worst with paint and organic solvents, and rise the longer debridement is delayed.