Lateral Parapatellar Approach for Total Knee Arthroplasty in Valgus Knee or Patellar Subluxation

Summary

In patients with valgus deformity of the arthritic knee, the contracted lateral soft tissue structures must be released before performing total knee arthroplasty (TKA). In subluxation of the patellar, release of the lateral patellar retinaculum must be carried out to keep the patella in the central part of the patellar sulcus of the femoral component and then to have good patellar tracking. Otherwise, inadequate patellar tracking will remarkably reduce the longevity of the knee prosthesis. In a series of more than 1000 consecutive TKA, 120 knees were operated on by means of the lateral parapatellar approach (LPPA). The knee joints were exposed after releasing the contracted lateral tissues, such as the retinaculum, joint capsule, and iliotibial band. The advantages of this approach include less damage to the blood supply of the patella and better tracking of the patella. In all these cases, the TKA was performed without difficulty. Excellent patellar tracking was observed immediately after each operation and at a later follow-up visit as well. Muscle power of the quadriceps recovered satisfactorily. Short-term functional results as rated by the Hospital for Special Surgery scoring system were excellent. Also, no peroneal nerve palsy or herniation of the joint capsule was found.