De-rotational osteotomy is performed to improve the rotational alignment (torsion) of the lower limb. This is required in conditions where rotational malalignment of either the thigh bone (femur) or the shin bone (tibia) causes pain in the patellofemoral joint (anterior knee pain) or instability (patellar dislocation). You will be evaluated with CT scan with rotational profile prior to the procedure where surgeon will localize the malalignment (either in femur or tibia) and measure the correction angle on the planning software. Following the initial arthroscopic assessment, your surgeon will make a cut in the bone (osteotomy), turn or rotate the leg by a desired angle as per pre-operative planning to get desired alignment, re-fix the bone with metal implants. You will be advised gradual weight bearing and supervised physiotherapy following the surgery. The osteotomy usually takes about two to three months to heal, when you will be expected to return to full function.