Fig. 1

Modified Langenskiold & Grammont procedure. a The patella was dislocated laterally. b The patella was completely detached from the capsule and only attached to the quadriceps tendon and the patellar ligament. c A longitudinal line was generated on the synovium at the center of the new desired position for the patella. d An incision was created along the line, and the patella was circumferentially fixed to the synovium with a running absorbable suture. e The Q angle was significantly increased after the patella was medially relocated. We performed the Grammont procedure to decrease it. The patellar ligament was separated sharply from the tibial tuberosity, while keeping it attached to the periosteum distally. The insertion point was then shifted medially at least 1 cm and fixed to the medial periosteum by a suture. f The iliotibial band was harvested beforehand. After the completion of the modified Langenskiöld procedure, the iliotibial band was wrapped under the patellar ligament, passed through the intermuscular septum, folded around the adductor magnus tendon, and sutured back onto itself