Patellofemoral Pain Syndrome is a condition where the back of the patella (posterior part of the knee cap) repeatedly comes in contact with the femur or thigh bone causing stress and friction. The stress and friction then causes pain and discomfort, emanating from the area where the kneecap and the femur meet. Patellofemoral pain syndrome is one of the most common problems encountered in sports medicine. And most athletes are diagnosed of this condition.
The Anatomy of the Knee Showing the Proximity of the Knee Cap to the Femur
Prevalence of Patellofemoral Pain Syndrome (PFPS)
In This Article
- 0.1 Prevalence of Patellofemoral Pain Syndrome (PFPS)
- 0.2 How Does Patellofemoral Syndrome (PFPS) Happen
- 1 Patellofemoral Pain Syndrome Symptoms
- 2 Patellofemoral Pain Syndrome Causes
- 3 Patellofemoral Syndrome Diagnosis
- 4 Treatment
- 5 Prognosis
- 6 Prevention
PFPS usually happens to athletes or sports enthusiasts. Dedicated athletes and beginners are most affected. Women are twice predisposed to this condition than men. Aside from athletes, older people with osteoarthritis are also at risk for developing PFPS.
How Does Patellofemoral Syndrome (PFPS) Happen
The problem of PFPS begins at the patellofemoral joint; this is the area where the patella or knee cap comes in contact with the femur or thigh bone. When we move, the patella normally glides over the patellar groove, and its movement is stabilized and controlled by muscles, ligaments and tendons surrounding it. Intense, vigorous, prolonged and repetitive movements can cause enormous stress on these connective structures surrounding it. Ligaments and tendons may tear dislocating the knee cap and friction from the movement of the kneecap against the femur can spark and inflammation. These disturbances then cause patellofemoral pain syndrome.
Patellofemoral Pain Syndrome (PFPS)
Patellofemoral Pain Syndrome Symptoms
- Tenderness on the inside borders of the patella or kneecap
- Swelling of the knee
- Pain that worsens upon walking up and/or down
- Presence of an aching pain particularly on the knee joint (around, under and in front of the patella)
- A click or crack sound upon bending the knee
- Feeling of discomfort when sitting for a long time
- Q angle is greater than 18-20°
- Possible atrophy of the quadriceps especially for prolonged cases
- Muscle tightness (iliotibial band, quadriceps, hamstrings and vastus lateralis)
Patellofemoral Pain Syndrome Causes
- Weak Quadriceps Muscles
The quadriceps is a set of muscles destined to absorb shock for the knee joint. Strong quadriceps muscle help disperse the stress that is placed on the knee due to vigorous activities. When the quadriceps muscles are weak, it could put a significant strain on the knees. People with patellofemoral pain syndrome are found to have weak quadriceps muscles; this may be the reason why women are twice at risk than men because women have weak quads compared to men.
Overuse of the quadriceps muscles can also cause patellarpain syndrome, this is what happens to most athletes or sports enthusiast. Remember that the quadriceps absorb shock and help support the knee joint, when these muscles are overused, the knee joint can be injured. Overuse usually occurs among runners, tennis players, weight lifters and jumpers. Runners who cover several miles per week or those who train on a downhill track are at most risk. This is because a significant weight is pressed onto the knee due to the repetitive and vigorous activity.
- Patellar tendinitis
Patellar tendinits or the inflammation of the patellar tendon can also cause Patellofemoral pain syndrome. This tendon connects the knee cap to the tibia. When this tendon inflames, it can cause pain on the knee joint. Patellar tendinitis can result from the following:
- Playing sports that involves jumping such as basketball
- playing on a hard or rough surface
- sudden, vigorous work out
- Presence of scar tissue and adhesions after surgery
- Malposition of the Knee Cap or Maltracking
When the knee cap is somewhat tilted or pulled to the other side of the groove, friction from the knee cap and thigh bone begins to happen. This friction then causes inflammation of the quadriceps tendon, patellar tendon and the structures surrounding it leading to patellofemoral pain syndrome.
Patellofemoral Syndrome Diagnosis
A clinician diagnoses PFPS by doing the following measures:
The physician will ask your activity and the symptoms you have felt. This information helps the physician rule out other possible disease conditions.
In a physical examination the physician would check for the following:
- Assess and test for muscle strength
- Flexibility of muscles in the legs
- How far you can bend your knees
- Assess for tenderness of the tendons
- Check for pain
- Assess for mobility
X-rays help in the visualization of the following:
- Structural abnormalities
- Misalignment of the knee
- Presence of bone spurs
- Presence of loose fragments
Treatment of PFPS revolves around an exercise therapy that is painless. Athletes and sports enthusiasts are advised to undergo supervised exercise and combine it with ample rest. People with osteoarthritis are advised to do exercises that strengthen the quadriceps muscles. Leg raise is an activity that can strengthen the quadriceps muscle.
Avoidance of activities that cause pain
Modification of one’s activities is very essential in the treatment of PFPS; individuals affected are advised to avoid activities causing pain. Runners are advised to avoid running down hills and just cover short distances.
NSAIDs or Non-Steroidal Anti-inflammatories and Application of an ice pack
NSAIDs such as Motrin and Naproxen are prescribed to relive pain and inflammation. After an activity, an ice pack can be applied on the knee to reduce inflammation and also to relieve the pain.
Surgical intervention remains to be the last ditch effort to treat PFPS. Almost 90% of the cases improve without surgery, and this might only be warranted if structural or anatomical problems are present.
Application of Braces and Taping
A brace to prevent the patella from misalignment or moving out of position is also a recommended treatment. This prevents the patella from sliding off of the patellar groove causing friction and inflammation. Taping the knee cap can also aid to this problem.
PFPS patients have a good prognosis, especially following proper treatment. Most cases improve even without surgery.
PFPS can be prevented by following an appropriate exercise regimen, strengthening the quadriceps muscles and avoiding activities that greatly stress the knee and surrounding structures.