Arthroscopic findings in chronic instability of the ankle joint

The diagnosis of ligamentous instability at the ankle joint based on clinical and radiological findings is often ambiguous, particularly with respect to the severity of ligamentous injuries. Most patients can be treated satisfactorily with late repair or reconstructions of the affected ligaments. However, if only a part of the ligamentous instability is addressed by surgery, some patients will be left with persistent disability. A consecutive series of 281 chronically unstable ankles (188 females, 93 males, age 35.8 (15-61) years] was preoperatively assessed by arthroscopy. The deltoid ligament was injured in 140 ankles (50%); of these, an associated injury to the lateral ligaments was found in 103 ankles (37%). While isolated lateral instability was found in 121 ankles (43%), isolated medial instability was found in 38 ankles (14%). Preoperative arthroscopy of the ankle has been shown to be a helpful diagnostic tool in assessing ligamentous incompetence and detecting associated lesions that would not, or only in part be recognized by imaging methods. It particularly helps to assess the continuity of the lateral and medial ligaments and to assess their competence to resist against applied stress forces, thereby allowing the surgeon to decide which structures might be addressed for reconstruction. Obviously there is no single entity of ankle instability. Although not proven in a randomized study, our first results support the belief that preoperative arthroscopy may improve the effectiveness of surgical treatment of the unstable ankle. This may be beneficial for the patient as well as cost saving.