Pain over the front of the knee is a common problem that may originate from a few sources. Patellofemoral pain is the most common. The patella (knee cap) acts as a guide to centralize the pull of the thigh muscles.  It also allows smooth gliding of the tendon from the thigh muscles over the front of the thigh bone. Extremely high compression loads on the patella occur as you bend your knee while standing. The cause of pain over the front of the knee is often due to patellofemoral syndrome, which is where the kneecap is pulled across to one side rather than tracking smoothly over the centre of the knee, which over time can result in damage to the smooth cartilage covering the joint.

The symptoms associated with patella femoral syndrome are pain during bent knee activities, such as squatting or walking upstairs, during which the highest compression load is placed on the patella.

Other causes of anterior knee pain are

Chondromalacia Patellae: This involves damage to the cartilage behind the kneecap.

Patellar Tendonitis: Inflammation of the tendon connecting the kneecap to the shinbone.

The factors leading to patellofemoral pain are the shape and position of the patella, instability of the ligaments stabilizing the patella, weakness of the muscles on the inside of the thigh, or tightness of the iliotibial band, which is one of the muscles that insert into the outside of the knee cap. Abnormal pronation of the foot or weakness in the gluteal muscles will cause the leg to rotate inward, which causes the patella to track unevenly over the front of the knees, which is a significant factor in causing patellofemoral syndrome.

The treatment of patellofemoral pain includes the short-term use of patella stabilizing devices, such as knee braces or taping, to assist the patella in tracking normally.

It is important to have a graduated strengthening program for the quadriceps and gluteal muscles. In the initial stages of rehabilitation, the safest quadriceps strengthening exercise is straight leg raises, as this does not load the patellofemoral joint. Short arc leg extensions and then lunging-type weight-bearing exercises can follow.

Stretching the illio tibial band if it is tight because it has fibers inserted into the lateral patella, which can increase the lateral displacement of the patella.  Stretching of the quadriceps, hamstrings, and calf muscles is needed if they are tight, as they also affect knee function.

Orthoses and supportive footwear are needed to correct abnormal pronation which helps reduce inward rotation of the leg and allows the patella to track more centrally over the front of the knee. Orthoses do not replace the need for gluteal strengthening exercises but work in conjunction with exercises to manage the problem.

Most people respond well to this treatment and rarely need surgery to correct patellofemoral maltracking.