Pain at the anterior portion (front) of the knee can be frustrating as it can become persistent. There are multiple possible diagnoses and factors which contribute.
Common diagnoses include:
- Irritation and/or damage to the cartilage surface of underneath the patella (knee cap) or the femur’s cartilage surface where the patella grove exists (thigh bone). This is known as patella femoral joint pain. Alleviating the pressure through the patella femoral joint and improving the patella’s tracking in the groove is the main focus of treatment.
- Pathology to the patella tendon or quadriceps tendon (tendon directly above or below the patella). This is known as a tendinopathy. Pain is usually very focal to a single point on the tendon and aggravated by high shock loading of the tendon, e.g. jumping and explosive changes of direction. Improving the tendons ability to accept load is the main focus of treatment.
- Bursa surround every joint, they are small fluid filled sacks that are designed to enable a tendon so slide over bone or others structures without friction. When there become swollen it is known as a bursitis. Treatment involves unloading the bursa and treating inflammation.
- Hoffa’s fat pad can be irritated by the patella and direct trauma. It is located beneath the patella to provide padding when kneeling. Unloading the fat pat and treating inflammation is the main focus of treatment.
- Retinacula overload and injury. There is a retinaculum (supportive tendon band) either side of the patella to support it from either side enabling it to track in the middle. In a patella dislocation the medial retinaculum can be torn. In persistent patella maltracking the lateral retinaculum is often too tight for the medial causing overload and pain. Physiotherapy and a guided strength program can help restore this balance.
- In adolescents/children, issues with the growth plates of the tibia and patella can occur these are Osgood-Schlatters and Sinding-Larsen-Johansson. Load management through the growth plate is a main focus of treatment.
The knee is essentially a weight bearing hinge influenced greatly by the joints above and below (hip/core and ankle/foot). So treating the knee involves exercises for all of these areas. An example of common factors that can cause patella femoral joint pain are outlined below:
- Tight lateral structures on the outside of the thigh. Common treatment for this can include massage/self-massage (foam roller spikey ball), dry needling and stretching. Taping / patella bracing once the lateral side is loosened off can help get the patella tracking well again if the medial retinaculum is overs stretched or the vastus medialis obliquus is under developed (inner quadrapceps muscle).
- Tight calves and stiff ankle in to dorsi flexion. This causes an early heel lift and increased the load through the patella femoral joint. Previous ankle injury can lead to stiffness in the ankle.
- Pronation of the feet. When your feet over pronate the tibia gets internally rotated this can lead to maltracking of the patella in the groove. The rolling of the foot if significant can also move the knee inward when accepting load.
- Weakness of the outer glute/hip muscles. When the knee moves inward the hip musculature has to control it. If the glutes and core lack control, strength or endurance patella femoral pain can be worsened.
- Poor load transfer through the mechanical chain. Landing stiff and or lacking control of the entire chain can over load the patella. Practice should be extended to these quicker movements in a rehab program if required.
- Poor equipment / equipment set up. For example, footwear or a bike fit with a low forward seat and cleat position can worsen patella femoral joint pain.
If you have anterior knee pain, please come and get it checked out at Greensborough Physiotherapy Clinic. Identification of each factor in order of importance can simplify and speed up your recovery.
Greensborough Physiotherapy Clinic