Patellar tendinitis is also known as jumpers knee, and it affects a lot of active people. It is an overuse injury that affects the quadriceps tendon where is inserts into the patella and the patellar tendon. It is also knows as, quadriceps tendinitis, patellar apicitis, volleyball or basketballers knee. It is found in athletes that put a lot of pressure onto the knee extension system, basically those who need to jump a lot, or run a lot for long periods. This is one of the most common athletic knee injuries.
The main activity that leads to jumpers knee or patellar tendinitis, is jumping… any kind of jumps. The landing phase, where the quadriceps extensors are forced to decelerate (work eccentrically) is the most stressful to the tendon. This deceleration in an unprepared or under conditioned knee is the most common factor in developing patellar tendinitis. A study was done with volleyball players, and it was found that from those who trained at least four times a week, 40% of subject develop clinical symptoms due to overstraining the patellar tendon. Those who train on very hard surfaces such as concrete are also much for likely to develop problems. If the floor is less able to absorb the force it places more strain on the muscle and tendon. The make up of the athlete is another minor factor in developing patellar tendinitis. The angle in which the knee and the hip line up can be important. The main factor is obviously mechanical stress and chronic overload, but valgus in the knee can also cause the problem.
Muscles imbalances can also be a common contributor, although not the most important. Those muscles that stabilise the pelvis and the lower body are important in regards to this condition. If you hamstrings and posterior chain are tight, you can cause extra stress and strain on the knee extensors (quadriceps). Weak hip flexors, glutes and lower ab muscles can also be a factor causing increased strain on the knee. An inadequate force distribution is produced during a jump and more pressure is placed on the knee. Therefore it might be an idea to make sure your hips and lower body are strong, stable and balanced.
So basically, it is now obvious to researchers and those in the medical field that excessive strain is the main cause of jumpers knee, and training on hard surfaces will exacerbate that.
Clinical Symptoms of Jumpers Knee
The main symptom of jumpers knee is an intense pain one touch along the patellar tendon. This pain can also be produced when you extend the leg, passively or with resistance. It has different stages of pain… one suggestion of the classification is below.
- Stage 1: Pain only after sports activity.
- Stage 2: Pain at the beginning of sports activity, disappearing after warm up and reappearing after activity.
- Stage 3: Pain at the beginning, during and after sports activity.
- Stage 4: Constant pain at rest during activity. Unable to participate in sports.
- Stage 5: Complete rupture of the patellar tendon.
There are several ways to diagnose it, the most common being via ultrasound. You will be able to see the state of the tendon, whether it is just minor swelling, large abnormalities such as thickening of the patellar or ruptures.
Now you have the basics of what Patellar tendinits actually is…we can start talking more about treatment of jumpers knee.