Alignment of the extensor apparatus of the knee by alar and tuberosity transposition in recurrent subluxation of the patella and in external patellar hypertension syndrome.

In consideration of the multiple anatomical structures involved in recurrent subluxation of the patella and in external patellar hypertension syndrome, the authors propose an operation which allows for complete realignment of the extensor apparatus by transposition of the anterior tibial tuberosity, division of the external alar ligament, tightening of the internal alar ligament, and correction of the muscular insertions. In particular, removal of a capsulofascial band medially and its reimplantation into the external incision is proposed, thus avoiding the formation of retractive scar tissue. The long-term results, which were overall satisfactory, confirm the effectiveness of the operation proposed.