Colles' Fracture

Definition

Mechanism

• Fall on an outstretched hand (FOOSH) with the wrist in dorsiflexion and forearm in pronation
• Tension on the volar aspect causes the fracture line to extend dorsally
• Compression on the dorsal side produces dorsal comminution
• Low-energy mechanisms (e.g., simple falls) cause mainly extra-articular, minimally displaced fractures in elderly patients; high-energy mechanisms in younger patients produce comminuted or intra-articular fractures

Epidemiology / Risk Factors

• Most common in older women with osteoporosis (post-menopausal)
• Risk factors: decreased bone mineral density, female sex, white ethnicity, early menopause, prolonged steroid use

Fracture Characteristics

• Dorsal angulation of the distal radial articular surface
• Proximal and dorsal displacement of the distal fragment
• Radial displacement of the carpus
• Radial shortening (negative ulnar variance)
• Associated ulnar styloid fracture in ~60% of cases
• May extend intra-articularly into the radiocarpal or radioulnar joint ("die-punch" fracture)

Clinical Presentation

• "Dinner fork" deformity - the classic appearance on physical exam and lateral X-ray
• Pain, swelling, and tenderness over the distal forearm
• Palmar paresthesias - from pressure or traction on the median nerve
• Neurologic exam is mandatory before and after any reduction attempt

Radiology

• Distal metaphyseal fracture with radial shortening
• Intra-articular extension into radiocarpal or radioulnar joint if present
• Ulnar styloid fracture

• Best shows the dorsal angulation and comminution
• Loss of normal volar tilt of the distal radial articular surface

Radiographic Criteria for Instability (Indicating Likely Surgical Need)

Management

Stable, Non-displaced Fractures

• Double sugar-tong splint (one from elbow to wrist, second extending to axilla) for 3-5 days, then short-arm cast for 4-6 weeks
• Serial radiographs at 1, 2, and 6 weeks to confirm no displacement
• Urgent outpatient orthopedic referral within 7-10 days

Displaced Fractures - Closed Reduction

• Hematoma block - most practical: 22-gauge needle on dorsum of distal radius, withdraw until hematoma encountered, instill 5-10 mL of 1% or 2% lidocaine ± bupivacaine
• Bier block (IV regional anesthesia)
• Median, radial, ulnar, or brachial plexus nerve blocks
• Procedural sedation

1. Apply finger traps to provide longitudinal traction - relaxes deforming muscle forces; may alone achieve reduction
2. Push distal fragment distally and palmarly while holding the forearm firmly
3. If periosteal entrapment is suspected - re-create then reverse the injury mechanism under traction to unfold the periosteum

• Double sugar-tong splint or sugar-tong splint - do NOT apply circumferential cast immediately (edema risk)
• Allow finger movement; immobilize wrist
• Orthopedic follow-up within 2-3 days

Indications for Surgery

• Unstable, severely comminuted, or intra-articular fractures
• Fractures unreducible by closed means
• All open fractures
• Neurovascular compromise
• Dominant-wrist fractures in high-demand (very active) patients
• Loss of reduction after closed treatment

Complications

Differential Diagnosis / Related Fractures

• Smith's fracture ("reverse Colles'") - volar angulation/displacement, from fall on a flexed wrist
• Barton's fracture - intra-articular fracture-dislocation of the radiocarpal joint (dorsal or volar variant)
• Chauffeur's / Hutchinson's fracture - radial styloid fracture
• Galeazzi fracture - distal radius fracture with DRUJ disruption

• Tintinalli's Emergency Medicine, 9th ed., p. 1847
• Rosen's Emergency Medicine, p. 612
• Pfenninger & Fowler's Procedures for Primary Care, 3rd ed., p. 1321