Total knee arthroplasty with subvastus approach in patient with chronic post-traumatic patellar dislocation☆

Chronic lateral dislocation of the patella is a rare condition and acquired causes are usually secondary to knee trauma. The neglected chronic dislocation leads to progressive genu valgum and external tibial torsion deformities with subsequent gonarthrosis, which becomes painful and debilitating. There is no consensus regarding treatment of these patients, but total knee arthroplasty (TKA) is a useful therapy in cases of painful symptomatic gonarthrosis. Few reports have shown that subvastus approach and lateral release may be a valid option for TKA, since it allows the correction of valgus deformity and patellar tracking without interrupting vascular blood supply of patella. This article reports a case of TKA and extensor mechanism realignment without patellar resurfacing in a patient with genu valgum and chronic post-traumatic patellar dislocation with satisfactory results after two years of follow-up.