Objective: Approach to the knee joint for total knee arthroplasty (TKA) with gentle soft-tissue handling.
Indications: Primary TKA with range of motion>or=100 degrees, leg axis up to 10 degrees varus or valgus, body weight<100 kg.
Contraindications: Contracted knees, leg axis>10 degrees varus or valgus, obesity, previous knee surgery except arthroscopic procedures, rheumatoid arthritis.
Surgical technique: Anterior midline incision. Soft-tissue preparation and capsule incision start at the upper tip of the patella and are continued distally along the medial patellar border ending at the tibial tuberosity. After opening of the joint, the patella is dislocated laterally without everting it. Exposure of the articular surface using a "mobile window". Preparation and insertion of the TKA components using special instruments. Wound closure in layers.
Postoperative management: Mobilization on crutches with full weight bearing starting on the day of surgery. Daily medical training therapy. Passive motion therapy continued twice a day. Low-dose heparin s.c. for 35 days after surgery.
Results: In a prospective randomized clinical study, 50 patients with a quadsparing (QS) approach were observed up to 3 months after surgery. In three patients, the use of large femoral components required an extended approach. During the hospital stay knee flexion was significantly greater in patients with the QS approach than in patients with the standard procedure (midvastus approach). There were no differences in implant positioning, Knee Society Score and complication rate between both groups. Use of the QS approach prolonged the duration of surgery by 25 min.