About This Page
This is a clinician-written, evidence-based summary aligned to the 2026 MLA Content Map. It is intended for medical students and junior doctors preparing for the UKMLA. Always cross-reference with NICE guidance, local protocols, and clinical judgement.
The Bottom Line
- Distal radius fracture with dorsal displacement, dorsal angulation, and radial shortening — "dinner fork" deformity
- Mechanism: fall on outstretched hand (FOOSH) — classic fragility fracture in postmenopausal women
- Treatment: undisplaced/minimally displaced = below-elbow backslab then cast for 6 weeks. Displaced = manipulation under anaesthesia (MUA) + cast or surgical fixation (ORIF)
- Assess neurovascular status (median nerve compression) and check for associated injuries (scaphoid)
- Assess for osteoporosis — Colles fracture is a fragility fracture sentinel event
Overview
A Colles' fracture is a fracture of the distal radius with dorsal displacement and angulation of the distal fragment, typically within 2.5 cm of the wrist joint. It produces the characteristic "dinner fork" deformity when viewed laterally. The classic mechanism is a fall on an outstretched hand (FOOSH) with the wrist in dorsiflexion. It is the most common fragility fracture of the wrist and serves as an important sentinel event for underlying osteoporosis. A Smith's fracture is the reverse pattern — volar displacement of the distal fragment ("garden spade" deformity).
Epidemiology
Colles' fracture has a bimodal distribution: young adults (high-energy trauma) and postmenopausal women (low-energy fragility fracture from osteoporosis). Incidence increases markedly after age 50 in women. Approximately 70,000 distal radius fractures occur annually in the UK.
Clinical Features
Symptoms
Wrist pain immediately after a fall on outstretched hand
Swelling and bruising around the wrist
Inability to move wrist normally
Paraesthesiae in median nerve distribution (acute carpal tunnel from haematoma/swelling)
Signs
"Dinner fork" deformity: dorsal displacement of distal fragment producing a step deformity when viewed laterally
Tenderness over distal radius
Swelling and bruising
Assess neurovascular status: median nerve (sensation thumb-index-middle), radial pulse, capillary refill
Investigations
First-line
AP and lateral wrist X-rayShows distal radius fracture with dorsal displacement and angulation. Assess: radial height, radial inclination, volar tilt, ulnar variance, intra-articular involvement
Second-line
CT wristIf intra-articular extension suspected on X-ray — guides surgical planning
Check for associated injuriesScaphoid fracture (anatomical snuffbox tenderness), DRUJ disruption (ulnar styloid fracture), lunate dislocation
Specialist
FRAX/DXAAssess for osteoporosis in ALL patients over 50 with fragility fracture
1
Initial management
- Analgesia, ice, elevation
- Neurovascular assessment — document median nerve function
- Backslab (below-elbow) in neutral position
2
Definitive management
- Undisplaced or minimally displaced: below-elbow cast for 6 weeks. Fracture clinic review at 1 week
- Displaced: manipulation under anaesthesia (MUA) — closed reduction under Bier block or GA. Apply cast and check post-reduction X-ray
- Surgical fixation (volar locking plate — ORIF): if unstable, intra-articular, irreducible, or re-displaces in cast
- Follow-up X-ray at 1–2 weeks to check alignment maintained
3
Rehabilitation and osteoporosis
- Physiotherapy: finger and shoulder exercises while in cast. Wrist rehabilitation after cast removal
- Assess osteoporosis: FRAX risk assessment, arrange DXA, start bone protection if indicated
Complications
- Malunion: If reduction lost — may require corrective osteotomy
- Median nerve compression: Acute carpal tunnel from swelling/haematoma — may require urgent decompression
- Stiffness: Finger and wrist stiffness — emphasise early finger exercises
- Complex regional pain syndrome (CRPS): Chronic pain, swelling, colour changes — ~5%
- Tendon complications: EPL rupture (weeks-months after Colles' fracture — inability to extend thumb IP joint)
- Osteoarthritis: If intra-articular component
UKMLA Exam Tips
- 1Colles = dorsal displacement (dinner fork). Smith = volar displacement (garden spade). Know the difference
- 2FOOSH mechanism in elderly woman = classic fragility fracture — assess for osteoporosis
- 3Always check median nerve function (acute carpal tunnel) and scaphoid tenderness
- 4EPL rupture: late complication — inability to extend thumb IP joint. Occurs weeks-months after fracture
- 5Smith fracture mechanism: fall on dorsum of hand or direct blow to dorsum of wrist
practicetest your knowledge on colles' fractureApply what you've learnt with UKMLA-style questions from the iatroX Q-Bank — musculoskeletal and beyond.
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