Treatment of malunited fractures of the anterior tibial spine.

Avulsion fractures of the anterior tibial spine are uncommon injuries, and most often seen in childhood. They can be associated with other intraarticular lesions and have, if adequately treated, a good long-term prognosis. In adults these fractures can be complicated by loss of knee extension because of the displacement of the bony fragment. This is most often as a result of non- or malunion of the displaced fragment. We review two cases of malunited fractures of the anterior tibial spine. Both patients reported persistent knee pain and loss of knee extension, and had had an anterior knee laxity for a long time. They had been treated extensively by physiotherapy. In one patient, arthroscopy in another hospital revealed no reasons for the clinical symptoms. More than twenty years after the initial trauma, both patients visited our hospital. A radiograph and a magnetic resonance imaging were respectively carried out both of which revealed a malunited avulsion fracture. According to the examinations, the patients were treated by open reduction and internal fixation, and in the follow up exploration both no longer had discomfort. Clinical and radiological features of this less common and rarely reported injury are discussed and the surgical treatment is demonstrated.