Current concepts: Lateral ankle instability

The past 15 years of investigation into chronic lateral ankle instability have been marked by an improved quality of research and an advanced understanding of its pathoanatomy, biomechanics, and operative options. Despite significant gains made by many studies, a degree of uncertainty still remains as to the optimal means of preventing, diagnosing, and treating this common malady. In most long-term single procedure and comparative studies, particularly when factoring in length of followup, anatomic ligament repairs and, more recently, anatomic tenodesing reconstructions appear to obtain the best functional results for refractory lateral ankle instability. While most of the anatomic and nonanatomic ligament reconstructions have proven effective as primary procedures for lateral ankle instability, the Broström-Gould repair provides acceptable long-term results in conjunction with the lowest complication rates (Grade B recommendation). Not every patient, however, appears suitable for this approach. Those with cavovarus foot deformity, generalized hyperlaxity, longstanding instability, high-functional demands, poor soft tissues, or failed repair should be considered candidates for alternative procedures such as combined foot realignment, gastrocnemius recession, or augmented reconstruction perhaps with one of the tenodesis procedures. Interestingly, patient satisfaction and selected outcomes scores remain similar for anatomic and nonanatomic procedures in many of the same papers, even with long-term followup. This may indicate the need for a differently weighted, more reliable measure of ankle instability surgery, as emphasized by Brodsky et al.,18 who showed a lack of sensitivity in the AOFAS ankle and hindfoot score in evaluation of patients with chronic lateral ankle instability. The Chrisman-Snook procedure has the best reported results to date of the nonanatomic reconstructions, although modifications placing the graft in a more anatomic position have shown encouraging results in clinical and biomechanical studies.19,30,117,127,129,137 The recent surge of interest in newer 'anatomic tenodeses' is based on the potential benefit of gaining a mechanically sound repair while maintaining normal ankle joint kinematics.29'24 Enthusiasm for their theoretic advantages and outcomes, however, must be tempered until they are subjected to longer-term scrutiny. More extensive followup of the nonanatomic reconstructions has begun to highlight the seemingly greater risks associated with operative dissection as well as the importance of normal ankle kinematics, because high rates of perioperative complications and eventual arthritic changes in the ankle being increasingly documented after these procedures.54,61. Copyright © 2006 by the American Orthopaedic Foot & Ankle Society, Inc.