What regions of the patella are predominantly in contact during 135 degrees of flexion?

During 135 degrees of knee flexion, the regions of the patella that come predominantly into contact are the lateral and medial facets. At this degree of flexion, the patella moves more deeply into the intercondylar notch of the femur, and both the lateral and medial facets make contact with the femoral condyles.

This contact is significant because it helps to stabilize the knee and ensure smooth movement during activities such as squatting or sitting. The alignment and contact area shift due to the angle of flexion, emphasizing the importance of these specific regions of the patella when the knee is significantly flexed. Understanding the anatomy and mechanics of patellar contact areas is crucial for comprehending knee function, diagnosing injuries, and devising rehabilitation strategies for those with knee issues.