PFPS - PATELLOFEMORAL PAIN SYNDROME

source: Steadman-Hawkins

• As the knee bends and straightens, the patella slides within a slot on the femur called the trochlear groove.
• The patella moves in many directions within this groove to provide efficient, frictionless movement up and down, side-to-side, rotational, and tilting.
• The bone surfaces are covered with articular cartilage to make joint movement smooth.

 What is Patellofemoral Pain Syndrome?

A common knee disorder which often affects the senior athlete along with runners and jumpers. Also called runners knee. Causes are:

• Overuse

• A change in activity

• An altered metabolic status

• Structural alignment and muscular weakness or imbalance which may cause the patella (kneecap) to track improperly on the femur (thigh bone) during movement.

Different disorders that cause pain around the kneecap include:

• infrapatellar tendonitis (jumper's knee) - which affects the tendon just below the kneecap

• chondromalacia patella - which involves damage to the cartilage surface of the patella

• quadriceps tendonitis - which affects the tendon attachment above the patella

• plica syndrome - in which joint tissue becomes inflamed and/or stiff, causing pain and tightness in the joint

What is patellofemoral pain syndrome and what can cause it?

• Overuse: repetitive bending and straightening of the knee that occurs in running may lead to the disorder because of the increased pressure points between the patella and femur when the knee is bent. A constant bending motion, especially on the weighted leg, can irritate the patella and cause a bone bruise to form.
• Alignment: The quadriceps alignment between the hip and the knee (the Q angle) is thought to affect patellar tracking. A larger than normal Q angle (greater than 20 degrees) may be more susceptible to patellofemoral pain. Pain may be felt more on the outside of the patella and femur because of increased pressure on these contact areas.
• Muscular weakness: A weakness or strength imbalance of the quadriceps muscles may alter the tracking of the patella.
• Muscular & Tendon tightness: The muscular structures that cause movement in the knee and hip must be flexible. If any one muscle or muscle group is tighter than the rest, patellar instability can occur.
• Flat feet (excessive foot pronation): little or no arch in the foot. As the foot rolls inward, the tibia compensates by rotating inward, disturbing the normal mechanics of the patellofemoral joint.
• A decrease in patellar mobility: the kneecap tightens, losing its normal ability to move in many directions.

 Symptoms

 Diagnosis

• reproduce the symptoms by pressing on the kneecap, particularly when the knee is bent and then straightened.
• check for tenderness and patellar motion
• assess alignment and flexibility
• evaluate the muscular strength and coordination of the leg

• arthritic conditions
• loose bodies (bone fragments in the joint)
• patellar mal-alignment
• varus or valgus mal-alignment (bow-legs or knock-knees)
• infection or a bone tumor

• a bone bruise or stress fracture
• cartilage loss or deterioration
• infection or a tumor

• the condition of the ligaments, cartilage, and menisci
• a swollen plica (a normal fold of tissue which can be painful when it becomes inflamed and enlarged).
• Tendonitis or partial tearing with nodule formation in the patellar tendon

 Non-Operative Treatment

PFPS can usually be effectively treated with a non-operative treatment program.

• Activity modification: physical activities should by decreased by 30% and should be limited to those with no impact, such as swimming or bicycling. Uphill walking or treadmill at a 7% grade is also a good choice. Exercises that cause pain should be avoided.

• Anti-inflammatory medication such as ibuprofen is recommended

• Icing - see P.R.I.C.E.

• Specific exercises to strengthen and rebalance the muscles about the knee.

• A knee sleeve, splint, or taping that will support the joint during healing. (Special sleeves can keep the patella tracking properly during motion.)

• Special footwear or orthotics can support the arch and absorb impact.

• Non-operative recovery usually takes 6 weeks or more.
• Sport activities that heavily load the knee should only be resumed very gradually and cautiously.
• To reach pre-injury activity level, the patient must build greater strength and flexibility in the muscles around the knee than existed before the injury.
• By maintaining a high level of fitness, the patient will reduce the likelihood of re-injury.

 Operative Treatment

• A diagnostic arthroscopy allows the doctor to examine and treat the inside of the joint. In this procedure, instruments are inserted through small incisions in the knee. Rough or frayed spots in the cartilage that covers the bone can be smoothed, plica can be trimmed, and the patella can be realigned if necessary.

• Crutch use, usually necessary for one to three weeks after surgery
• Two to three months of healing and rehabilitation
• A gradual return to desired activities that usually take between three and six months.

• A knee with PFPS hurts during exercise because of the increased fluid in the joint or swelling in the tissues.
• This interferes with the motion of the knee and can cause increased friction in the joint as the knee moves.

• A typical non-operative program can take six weeks or more.
• It is a good idea to give the knee at least as much time for the symptoms to begin to improve as it has experienced discomfort.

• A very high percentage (about 95%) of patients with PFPS will respond successfully to a conservative, non-operative treatment program such as the one outlined here.