Patellofemoral complications after TKA are mostly avoided with appropriate operative technique. Although most orthopedic surgeons performed using a medial parapatellar approach at TKA, but a large amount of the patellar blood flow is blocked by this procedure. A certain surgical exposure, including the midvastus and subvastus approach, has resulted in good clinical results. It is important to maintain the integrity of the extensor mechanism. But the southern or subvastus approach has inadequate exposure in some patients. And then we have had the primary total knee Arthroplasty using midvastus approach in 98 cases, 68 patients. Mean follow up is 30 months, between from 20 months to 43 months.

We estimated parameters of total blood loss, surgical time, difficulty of exposure, number of lateral releases. The clinical parameters of range of motion, ability to perform a straight leg raise, and the number of operative or postoperative complications were evaluated. The patients who had the midvastus approach had minor blood loss, resonable surgical time, no difficulty of exposure even in patients with severe varus or valgus deformities, required lateral retinacular releases only 5% of the cases. The range of motion was all above 120 degrees flexion, no extension loss, had a higher incidence of ability to straight leg raise and fewer complications as like superficial wound infection. The midvastus surgical approach have some more advantages with less pain and earlier control of the operative leg, and may be discharged from the hospital earlier. Because preserving the integrity of the vastus medialis insertion into the medial border of the quadriceps tendon and limited disruption of the extensor mechanism improves the rapid control of quadriceps muscle and improves the more stable patellofemoral articulation, and then evidenced a marked reduction in the need for lateral retinacular releases.

We recommend the mid-vastus surgical approach for total knee arthroplasty. The Midvastus approach is an efficacious alternative to the medial parapatellar approach for primary total knee arthroplasties in selected patients who are not obese and who have not had previous arthrotomy. And if needed more additional exposure, the muscle can be safely split by further dissection.