Patellofemoral Instability results from one or more dislocations or partial dislocations, also called subluxations. This misalignment can damage the underlying soft structures such as muscles and ligaments that hold the knee in place. Once damaged, these soft structures are unable to keep the patella (knee cap) in position.
Signs and symptoms of Patellofemoral Instability can include the following:
Patellofemoral Instability can be caused by a number of factors that affect the way the patella moves along the groove of the femur (trochlear groove) when the leg is bent or straightened. The patella normally moves up and down with a slight tilt without touching the other knee bones. In Patellofemoral Instability the patella does not maintain its normal path of movement and can slip out of the trochlear groove either partially (subluxation) or completely (dislocation).
Evaluating the source of Patellofemoral Instability is critical in determining your treatment options for relief of the instability. Your physician will perform the following:
The goal of conservative treatment for Patellofemoral Instability is to restore full range of motion by restoring the normal tracking pathway of the patella during flexion and extension of the knee. Treatment options may include closed reduction, pain medications, rest, ice, physical therapy, orthotics, and bracing. Surgical treatment of Patellofemoral Instability is sometimes necessary to help return the patella to a normal tracking path when conservative treatment options are unsuccessful
Patella (knee cap) is a protective bone attached to the quadriceps muscles of the thigh by quadriceps tendon. Patella attaches with the femur bone and forms a patellofemoral joint. Patella is protected by a ligament which secures the kneecap from gliding out and is called as medial patellofemoral ligament (MPFL).
Dislocation of the patella occurs when the patella moves out of the patellofemoral groove, (called as trochlea) onto a bony head of the femur. If the knee cap partially comes out of the groove, it is called as subluxation and if the kneecap completely comes out, it is called as dislocation (luxation). Patella dislocation is commonly observed in young athletes between 15 and 20 years and commonly affects women because of the wider pelvis creates lateral pull on the patella.
Some of the causes for patellar dislocation include direct blow or trauma, twisting of the knee while changing the direction, muscle contraction, and congenital defects. It also occurs when the MPFL is torn. The common symptoms include pain, tenderness, swelling around the knee joint, restricted movement of the knee, numbness below the knee, and discolouration of the area where the injury has occurred.
Your doctor will examine your knee and suggests diagnostic tests such as X-ray, CT scan, and MRI scan to confirm condition and provide treatment. There are non-surgical and surgical ways of treating patellofemoral dislocation.
Non-surgical or conservative treatment includes:
Surgical treatment is recommended for those individuals who have recurrent patella dislocation. Some of the surgical options include:
After the surgery, your doctor will suggest you to use crutches for few weeks, prescribe medications to control pain and swelling, and recommend physical therapy which will help you to return to your sports activities at the earliest.