Common causes of anterior knee pain
Patellofemoral pain syndrome is also sometimes known as runners knee is itself a generic term to describe pain resulting from friction between the patella and the femur bone as it glides over it. The actual source of pain could come from a number of sources. We explain the how patellofemoral pain is caused along with treatment and rehab programs with specific exercises.
Patellar tendinitis or patella tendinopathy would be a more accurate term to describe pain on the patella tendon (or patella ligament is it is sometimes known). Symptoms include pain at the bottom front of the patella with tenderness when pressing in. There is likely to be pain when contracting the quadriceps muscles with aching and stiffness after exercise. Jumping off the leg or sprinting may be painful depending on how bad the injury is. it is important this knee injury is treated early as this can be a stubborn condition to treat if if becomes chronic.
Osgood Schlatters disease is a condition that affects children between the age of 8 and 15. Symptoms include pain on the tibial tuberosity which is the prominent bony bit just below the knee at the top of the shin bone or tibia. The athlete needs to manage this condition as best they can but most children will grow out of it as long as they rest and look after the injury early on. Continuing to play and train in pain will prevent Osgood Schlatters from healing and may cause long term problems.
Less common causes of anterior knee pain
Synovial plica is a fold in the synovial membrane which surrounds the knee joint and contains the lubricating synovial fluid. The fold is found along the inside of the knee cap causing symptoms of pain and discomfort. It is often misdiagnosed as patellofemoral pain syndrome. The athlete may feel a sharp pain when squatting. A synovial plica may sometimes feel like a thickened band under the inside of the kneecap.
Housemaid's knee or pre patella burisits is inflammation of the bursa at the front of the kneecap. It is caused by direct pressure on the kneecap which irritates the bursa or sack of fluid which sits at the front of the patella. Symptoms include pain and swelling over the kneecap and just below it. The patella may feel warm to the touch and kneeling down will be painful.
Quadriceps tendinitis or quadriceps tendinopathy is an over use injury causing pain in inflammation to the quadriceps tendon as it inserts into the top of the patella or kneecap which over time leads to degeneration of the tendon as opposed to pure inflammation. Symptoms include pain during and after exercise along the top of the patella. There may be pain when contracting the quadriceps muscles and stiffness the next day. Crouching down onto the heels is likely to be painful, particularly when attempting to squat back up again.
Infrapatellar bursitis is similar to Housemaids knee in that it is swelling and inflammation of a bursa or fluid filled sack. However the infrapatella bursas are affected resulting in symptoms similar to those of jumpers knee with pain at the front and bottom of the kneecap.
Patellofemoral instability means the patient can feel like they have a sensation of the kneecap feeling loose when bending the knee. Symptoms also include pain and swelling at the front of the knee. Patellofemoral instability can be categorized into primary and secondary instability. If the condition is severe then full patella dislocations can occur.
Fat pad impingement or Haffa syndrome is pain and swelling from the soft tissue or fat pad under the kneecap of patella with symptoms of tenderness and pain around the bottom of and underneath the kneecap. Patients may have a history of being unable to completely straighten the knee. In extreme cases the bottom of the patella may protrude outwards from the swelling underneath. A therapist or trainer will perform Hoffas test to help diagnose the injury.
Sinding-Larsen-Johansson lesion affects children between the ages of 8 and 15 years. Symptoms will usually effect adolescents and include pain at the front of the knee which gets worse during and after exercise. The bottom or lower pole of the kneecap may be tender to touch. It would be simliar to jumpers knee where the patella tendon becomes inflamed or degenerates over time however this condition is more like Osgood Schlatters disease where there is a crumbling of the bone where the tendon attaches. The injury needs to be managed but it is something the child should grow out of.
Stress fracture of the patella is a hairline crack or fracture in the patella usually caused by overuse.
Tenoperiostitis of the upper tibia is inflammation of the sheath that surrounds the bone where the tendon attaches to it. Similar to shin splints which usually affects the lower third of the shin rather than closer to the knee.