The patella (kneecap) is held in place by the quadriceps and patellar tendons. Ligaments on either side also help stabilize the patella. Patellar tracking disorder is a painful knee condition caused by a problem with the bones, muscles or ligaments around the patella.
Structural problems in the legs can cause patellar problems to develop. Misalignment of the femur and tibia can cause the kneecap to shift outward. A shallow femoral groove can also cause the patella to slip out of place.
The four muscles of the quadriceps help guide the patella's movement. Weakness in any of the quadriceps muscles can pull the kneecap to one side. Timing problems between two of the muscles the vastus medialis oblique (VMO) and vastus lateralis (VL) can also cause the patella to shift sideways.
If the patella is injured, the lateral retinaculum (a ligament on the outside of the patella) may shrink and tighten. This can pull the kneecap out of its normal track.
As the patella shifts off its normal track, there is an increased possibility of dislocation (or near dislocation) of the kneecap. The uneven pressure on one side of the kneecap may damage the cartilage under the kneecap, causing pain. This condition is called ELPS (Excessive Lateral Pressure Syndrome).
Treatment is usually non-surgical and includes physical therapy to strengthen the quadriceps, stretching exercises for the quadriceps and hamstrings, rest from any aggravating activity, ice, anti-inflammatory medication, and bracing or taping the patella for stabilization. In some cases, minimally invasive knee surgery may be performed to adjust the patella position.