What is the treatment for distal fibula and medial malleolus fractures?

Treatment of Distal Fibula and Medial Malleolus Fractures

For nondisplaced distal fibula fractures below the syndesmosis, treat conservatively with a removable splint for approximately 3 weeks, while displaced or unstable bimalleolar fractures (involving both distal fibula and medial malleolus) require surgical fixation with open reduction and internal fixation (ORIF). 1

Initial Assessment and Treatment Algorithm

Nondisplaced Fractures

• Conservative management with removable splint immobilization for approximately 3 weeks is appropriate for nondisplaced distal fibular fractures below the syndesmosis 1
• Radiographic follow-up at 3 weeks and at immobilization removal is essential to confirm adequate healing 1
• Active finger and toe motion exercises should begin immediately after diagnosis to prevent stiffness, as motion does not adversely affect adequately stabilized fractures 1, 2

Displaced or Unstable Fractures

• Surgical fixation is indicated when post-reduction imaging shows radial shortening >3mm, dorsal tilt >10°, or intra-articular displacement 1
• For bimalleolar fractures (both fibula and medial malleolus involvement), ORIF remains the standard of care for unstable patterns 3, 4

Surgical Fixation Options

Lateral Malleolus (Distal Fibula)

• Traditional plate fixation remains the gold standard, though intramedullary (IM) fixation has emerged as a viable alternative for almost all fracture patterns 3
• IM fibular nailing provides biomechanical efficiency with a soft-tissue friendly approach, achieving mean union time of 8.25 weeks and excellent functional outcomes (mean AOFAS score 89.30) 3
• IM fixation is particularly valuable for patients with poor soft tissues and significant comorbidities, showing no wound infections or nonunions in clinical series 5, 4
• Percutaneous screw fixation (100mm screw up the fibular medullary canal) offers minimally invasive stabilization for unstable fractures in high-risk patients 5

Medial Malleolus

• Headless compression screws provide superior outcomes compared to traditional partially threaded screws, with only 2% nonunion rate versus historical rates up to 20% 6
• Headless screws significantly reduce hardware removal needs (2% versus traditional higher rates) and minimize painful hardware prominence 6
• Traditional fixation with partially threaded screws and/or K-wire remains acceptable but has higher complication rates 6

Rehabilitation Protocol

• Maintain immobilization for approximately 3 weeks with radiographic confirmation of healing 1
• Never allow the splint to obstruct full finger and toe range of motion 2
• Gradual return to activity after 3-week immobilization period 1
• Monitor for complications including skin irritation and muscle atrophy (occurring in approximately 14.7% of cases) 1

Critical Pitfalls to Avoid

• Do not remove immobilization before 3 weeks without radiographic confirmation of adequate healing, as premature removal can lead to displacement or nonunion 1
• Watch closely for loss of reduction even in initially nondisplaced fractures, as displacement can occur during healing 2
• For patients with poor soft tissues or significant comorbidities, strongly consider minimally invasive techniques (IM nailing or percutaneous fixation) over traditional ORIF to reduce wound complications 5, 4

Management of Nonunions

• Nonunions of lateral and medial malleoli, though rare, require operative treatment with plate/screw fixation plus bone grafting 7
• Adjunctive grafting should be performed in nearly all nonunion cases, leading to reliable healing with mean time of 5.2 months post-surgery 7
• Patients treated for nonunions ultimately achieve similar functional outcomes compared to those with acute surgical fixation 7