Distal Radius Fracture

A distal radius fracture involves the distal radial metaphysis with or without extension into the radiocarpal or distal radioulnar joint.

The objectives of treatment are:

• Restore articular congruity
• Restore radial length
• Restore radial inclination
• Restore sagittal tilt
• Restore DRUJ stability
• Permit early hand and wrist rehabilitation

Normal distal radial parameters

Approximate normal values are:

• Radial height: 11 to 12 mm
• Radial inclination: approximately 22°
• Volar tilt: approximately 11°
• Ulnar variance: approximately neutral

These are useful references when assessing reduction.

Eponymous patterns

Colles fracture

Extraarticular distal radius fracture with dorsal displacement and dorsal angulation.

Classical dinner fork deformity.

Smith fracture

Extraarticular fracture with volar displacement and angulation.

Sometimes described as a reverse Colles fracture.

Volar Barton fracture

Intra articular volar rim fracture associated with volar radiocarpal subluxation or dislocation.

Highly unstable.

Dorsal Barton fracture

Dorsal rim fracture with dorsal radiocarpal displacement.

Chauffeur fracture

Radial styloid fracture.

Die punch fracture

Depression of the lunate facet caused by axial loading through the lunate.

Frykman classification

Based on radiocarpal and DRUJ involvement and the presence of an ulnar styloid fracture.

Type I

Extraarticular radius fracture.

Type II

Type I plus ulnar styloid fracture.

Type III

Radiocarpal joint involvement.

Type IV

Type III plus ulnar styloid fracture.

Type V

DRUJ involvement.

Type VI

Type V plus ulnar styloid fracture.

Type VII

Both radiocarpal and DRUJ involvement.

Type VIII

Type VII plus ulnar styloid fracture.

Fernandez classification

Based on mechanism.

Type I: Bending

Metaphyseal fracture such as Colles or Smith.

Type II: Shearing

Articular rim injury such as Barton fracture.

Type III: Compression

Articular impaction such as die punch injury.

Type IV: Avulsion

Radiocarpal fracture dislocation associated with ligament injury.

Type V: Combined

High energy injury involving multiple mechanisms.

AO/OTA concept

Type A

Extraarticular.

Type B

Partial articular.

Type C

Complete articular.

Increasing articular comminution increases treatment complexity.

Patients usually present after a fall onto the hand.

Assess:

• Deformity
• Swelling
• Open wound
• Skin tension
• Median nerve function
• Ulnar nerve function
• Radial pulse
• DRUJ tenderness

Acute median nerve compression is clinically important.

Progressive numbness in the radial three and a half digits, increasing pain and loss of two point discrimination after reduction may indicate acute carpal tunnel syndrome and requires urgent decompression.

Transient median paraesthesia caused by deformity can improve after reduction and should be distinguished from progressive acute carpal tunnel syndrome.

Obtain:

• PA wrist
• Lateral wrist
• Oblique view where useful

CT is important for:

• Complex intra articular fracture
• Die punch injury
• Barton fracture
• Preoperative planning

Immediate reduction

Urgently reduce fractures associated with:

• Neurovascular compromise
• Severe deformity
• Skin threat
• Acute median nerve compression

Use a hematoma block, regional anaesthesia or procedural sedation as appropriate.

After reduction:

• Repeat neurological examination
• Repeat vascular examination
• Obtain post reduction radiographs
• Apply a well moulded splint that accommodates swelling

Nonoperative treatment

Appropriate for a stable acceptably reduced fracture.

In older low demand patients, modest radiographic deformity can be well tolerated and operative fixation has not consistently improved long term patient reported outcomes compared with nonoperative care.

After swelling settles, transition to cast immobilisation.

Repeat radiographs during the first 1 to 2 weeks when loss of reduction is possible.

Operative indications

In physiologically younger adults, fixation provides better outcomes when post reduction alignment demonstrates approximately:

• Radial shortening greater than 3 mm
• Dorsal tilt greater than 10°
• Intra articular step or gap greater than 2 mm.

Other indications include:

• Unstable Barton fracture
• Irreducible fracture
• Open fracture
• Progressive median nerve compromise
• Failure to maintain reduction
• Severe comminution in an active patient

Volar locking plate

The most commonly used operative construct for unstable distal radius fractures.

Advantages include:

• Fixed angle support
• Subchondral support
• Early wrist movement
• Ability to capture separate radial and intermediate columns

Restore:

• Radial height
• Inclination
• Volar tilt
• Articular surface

Do not place the plate excessively distal beyond the watershed line because flexor tendon irritation or rupture, particularly flexor pollicis longus, can occur.

Distal screws must remain subchondral without entering the joint.

Use multiple fluoroscopic views because standard lateral imaging may miss intra articular screw penetration.

Dorsal fragments

Selected dorsal rim or highly comminuted fractures require:

• Fragment specific fixation
• Dorsal plate
• Combined approaches

External fixation

Bridge external fixation uses ligamentotaxis and is useful in:

• Severe swelling
• Open injury
• Highly comminuted fractures
• Damage control

It does not reliably elevate impacted central articular fragments by itself.

Ulnar styloid fracture

Do not fix every ulnar styloid fracture.

After radial reconstruction, assess DRUJ stability.

Fix the styloid base or repair the TFCC only when clinically significant DRUJ instability persists.

Rehabilitation

Encourage immediate:

• Finger movement
• Thumb movement
• Elbow movement

After stable internal fixation, wrist motion can often begin within the first 1 to 2 weeks depending on wound and fracture stability.

Major complications include:

• Malunion
• Acute or delayed carpal tunnel syndrome
• DRUJ instability
• Extensor pollicis longus rupture
• Flexor tendon irritation from volar plate
• Complex regional pain syndrome
• Radiocarpal arthritis
• Stiffness
• Loss of fixation