[Chronic recurrent ligament instability on the lateral ankle]

According to the literature, chronic ankle instability occurs after acute rupture of the lateral ankle ligaments in 10-20% of the cases. The etiology of the instability are ligamentous damage and functional neuromuscular disorder of the peroneal muscles. The standards of diagnostics are the history with the frequency of inversion trauma per period and the interval from the primary trauma, the clinical examination and radiological stress tests. Newer diagnostic methods, up to now not well established in clinical routine, include stabilometry, cybex-measurements of the pronator muscles, the evaluation of peroneal reaction time on a tilting platform and dynamic pedography. Conservative management of chronic ankle instability consists of wearing ankle braces and rehabilitation programs concerned with peroneal muscle strengthening and coordination training. The indication for surgical reconstruction of the ankle ligaments are a well-documented mechanical instability with the neuromuscular reflexes intact and a failed physiotherapeutic training program. The surgical procedure should be selected according to a priority list: 1. anatomical repair, eventually augmented with periosteum from the fibula, 2. Watson-Jones tenodesis, and 3. Chrisman-Snook tenodesis to treat a concomittant subtalar instability.