Fig. 1

Incision design a Asmall incision was made on the basis of posterior medial approach and assisted by lateral parapatellar approach b After cutting the retaining band, the patella and patellar ligament were pulled medially to clearly expose the intra-articular. c Schematic drawing of combined lateral peripatellar and posteromedial approaches. The distance between the two skin incisions should be more than 7 cm