KnotesFree Orthopaedic & FRCS notes, viva stations and higher order SBAs

Lateral ligament sprain of the ankle

High YieldFoot & AnklethinKbox SBA

Anatomy

The lateral ligament complex consists of:

  • anterior talofibular ligament (ATFL)
  • calcaneofibular ligament (CFL)
  • posterior talofibular ligament (PTFL)

The ATFL is injured most commonly.

Mechanism

A typical injury is inversion of a plantarflexed ankle. Greater injury may involve the CFL and, less commonly, the PTFL.

Assessment

  • swelling and bruising
  • tenderness over ATFL and CFL
  • ability to bear weight
  • bony tenderness requiring radiographs under Ottawa ankle rules
  • anterior drawer test for ATFL
  • talar tilt for CFL
  • assess syndesmosis and peroneal tendons

Treatment

Most injuries are treated non-operatively:

  • short period of protection and compression
  • early weight bearing as tolerated
  • restoration of range of motion
  • peroneal strengthening
  • proprioception and balance training

Chronic instability

Persistent recurrent giving way despite rehabilitation may require further imaging and, in selected patients, operative ligament repair or reconstruction.

Reference

Written/reviewed by Kishore Puthezhath

Professor of Orthopaedics and Consultant Paediatric Orthopaedic Surgeon

FRCS (Tr & Orth) revision resource

Reviewed: September 2026