What position places stress on the patellofemoral joint?

The correct answer focuses on how certain knee positions increase stress on the patellofemoral joint. In both terminal 30 degrees of knee extension during weight bearing and greater than 90 degrees of knee flexion during weight bearing, the alignment of the patella and its interaction with the femur create increased forces and potentially cause discomfort or dysfunction.

When the knee is in terminal 30 degrees of extension during weight-bearing, the patella is still engaged but not fully seated in its groove on the femur. This position can cause the patella to experience increased lateral forces due to muscle contractions, particularly from the quadriceps, which can lead to patellofemoral pain.

Similarly, when the knee is flexed greater than 90 degrees during weight bearing, the angle between the patella and femur alters, resulting in a significant increase in patellofemoral contact pressures and stresses. This position often mirrors activities like deep squatting, which can exacerbate patellofemoral joint pain or symptoms, particularly in individuals with existing conditions such as patellar tendinopathy or chondromalacia patella.

Together, these positions highlight the mechanics of the knee joint and how certain angles can lead to undesired stresses on the pat