Severe ankle sprains are the most frequent reason for emergency trauma consultations. Between 30% and 80% of sprains result in sequelae such as pain, joint derangement or instability. Ankle instability can itself lead to osteoarthritis if left untreated (1st cause of post-traumatic ankle osteoarthritis). To treat instability, ligament reconstruction is performed by harvesting the tendon of the gracilis muscle (inserted at knee level) to replace the damaged ankle ligaments. This tendon is also used for other ligament reconstructions (anterior cruciate ligament), so is not always harvested. Moreover, it represents an invasive procedure at a distance from the site of interest (the ankle), and can cause sensory nerve damage (20-60% of cases). For a long time, half of the peroneus brevis tendon was harvested as part of a now-defunct ankle stabilization technique (Hemi-Castaing). This tendon does, however, play a role in stabilizing the ankle.

Before considering harvesting the peroneus brevis as an alternative to harvesting the gracilis, it is important to ensure that the peroneus brevis remains functional after harvesting. The aim of this study was to evaluate the potential for tendon regrowth after harvesting half of the peroneus brevis tendon after Hemi-Castaing-type ankle stabilization surgery.

Inclusion Criteria:

• Adult one year after peroneus brevis harvesting (Hemi-Castaing)

Exclusion Criteria:

• No.

Patients at Saint-Etienne University Hospital who underwent Haemi-Castaing-type ankle stabilisation surgery.