Ankle impingement: combined anterior and posterior impingement syndrome of the ankle.

BACKGROUND: Simultaneous anterior and posterior ankle impingement has not been previously reported. We identified 62 patients with both anterior and posterior impingement and report the results of anterior arthroscopic and posterior open treatment.

METHODS: Between January, 1990, and December, 2003, 62 consecutive patients with symptoms and signs of both anterior and posterior impingement of the ankle were identified. Fifty-eight recorded a single injury or multiple ankle sprains. The most common mechanism of injury was inversion or plantarflexion. Initial conservative treatment failed in all patients and anterior arthroscopy and open posterior clearance were done. Followup averaged 11.4 months (up to 5 years). All patients showed posttraumatic synovitis at arthroscopy, and 48 had other arthroscopically-detected lesions, such as anterior tibial plafond lesions, ossicles, or soft-tissue impingement. The posterior arthrotomy revealed a bony cause for impingement in all but four patients, usually an os trigonum or a long posterior process of the talus.

RESULTS: Three patients had anterolateral tenderness after arthroscopy and three had tenderness of the posterior arthrotomy scar. There were no persistent neurologic complications. Fifty-eight patients were available for followup. Forty-seven (81%) had excellent or good outcomes, nine (15.5%) had fair outcomes, and two (3.5%) were graded as poor.

CONCLUSION: Usually, anterior and posterior impingement occur separately; however, there are patients who have symptoms and signs of both anterior and posterior ankle impingement. A single inversion or plantarflexion mechanism of injury may be responsible for this syndrome, although it may also be caused by repetitive inversion injury. Combined anterior arthroscopic and posterior open treatment obtained good results with minimal complications and morbidity.