Proximal fibula fractures - key points
Proximal fibula fractures involve the fibular head and neck. They may be isolated but are frequently associated with injuries around the lateral knee (lateral tibial plateau fracture, LCL/ACL injury, knee dislocation). The common peroneal (fibular) nerve wraps around the fibular neck and is highly vulnerable.
In the emergency department the priorities are haemorrhage/limb perfusion and pain control, careful neurovascular assessment with documentation, early immobilisation, appropriate imaging (low threshold for CT), and timely orthopaedic/vascular escalation where indicated (NICE NG38, NG39).
Anatomy and mechanism - practical implications
- The common peroneal nerve courses superficially around the fibular neck and divides into:
- Deep peroneal: motor to anterior compartment (dorsiflexion, toe extension); sensory to the first web space.
- Superficial peroneal: motor to lateral compartment (eversion); sensory to distal lateral leg and dorsum of the foot (except the first web space).
- Mechanisms: direct lateral impact, varus/rotational forces, avulsion injuries, and high‑energy trauma.
- Associated injuries (tibial plateau fracture, ligamentous disruption, knee dislocation) are common and alter management and imaging needs.
Clinical presentation
- Lateral knee pain and swelling with focal tenderness at the fibular head/neck.
- Weight‑bearing may be painful or impossible.
- Key neurological findings:
- Foot‑drop (loss of ankle dorsiflexion, toe extension) indicates deep peroneal dysfunction.