Treatment of chronic lateral ankle instability with the Chrisman Snook procedure

Purpose of the study We report our experience on lateral ankle instability treated by the Chrisman Snook procedure. We studied the objective and subje ctive results as well as the effect on peroneus brevis tendon function. Material and methods Among 110 patients treated for chronic lateral ankle i nstability between 1991 and 1997, 32 cases were treated with this technique . The average age was 25 years (16-37) and the average time to surgery from the initial trauma was 30 months. This was a retrospective study using the Karlson Peterson form while the laxity was measured with Telos device (120 N). Cybex testing was performed on 10 patients. Twenty-seven patients part icipated in sport. Results The follow-up ranged from 6 to 65 months (average 25 months). The a verage Karlson's score was 82.6 with 78 per cent excellent and good results . Lateral ligament laxity was reduced from 17 mm to 4 mm on Telos measureme nts and no osteoarthritis was noticed radiographically The joint mobility c onsistently returned to the preoperative level. Twenty four patients return ed to sport although half of the patients had some pain during sport activi ties or with fast walking. Discussion Males and patients participating in sporting activities had the best results and none of the patients had recurrent instability despite new sport injuries. The persistence of some pain may be associated with the lo ng period of instability prior to reconstruction in this group of patients. Conclusion The Chrisman Snook lateral ligament reconstruction is a technica lly easy and solid technique and we recommend it in patients with significa nt chronic lateral ligament instability.