Jumpers knee is primarily an over use injury affecting athletes involved in running and jumping sports, hence the term 'Jumpers Knee'. Repetitive strain causes inflammation or degeneration of the tendon.
There are a number of factors which may increase the likelihood of incurring a patella tendon injury.
The patella tendon, also known as the patella ligament joins the kneecap or patella to the shin bone or tibia. The patella tendon is extremely strong and allows the quadriceps muscle group to straighten the knee. Huge forces are transferred through the tendon, particularly in jumping to propel the individual off the ground as well as functioning in stabilizing their landing.
As such this tendon comes under a large amount of stress especially in individuals who actively put extra strain on the knee joint such as those who regularly perform sports that involve direction changing and jumping movements. With repeated strain, micro-tears as well as collagen degeneration may occur as a result in the tendon.
This is known as patellar tendinopathy or Jumpers Knee. It should be distinguished from patella tendonitis (tendinitis) as this condition indicates an acute inflammation of the tendon whereas tendinopathy is more about degeneration of the tendon. In practice the majority of chronic cases are more likely to be degeneration of the tendon rather than acute inflammation which should settle down after a few days rest.
It is likely that an athlete with patella tendonitis will have poor Vastus medialis obliquus (VMO) function. This is the muscle on the inside of the quadriceps near the knee. They may also have significant weakness in the calf muscles.
Premiership Physiotherapist Neal Reynolds talks about how to prevent jumpers knee or patella tendonitis.
Jumper's knee injury prevention
Our top tips for preventing Jumpers knee or patella tendonitis. These tips can be used if you have already suffered patella tendonitis once and are trying to prevent it coming back, or if you are an athlete involved in lots of jumping and want to prevent it developing in the first place!
Do not over-train! Performing too many high impact training activities will be too much for the tendon.
Look out for the early signs of pain and inflammation after training and act. Do not wait until this injury becomes bad - there is a long rehabilitation period once the injury becomes worse.
Identify any biomechanical problems that may increase the risk for example overpronation of the foot, a loose kneecap or a tight iliotibial band. If you are not sure, see professional help and advice.
Use eccentric strengthening exercises to make the knee joint strong enough to cope with the demands of the sport. Continue these exercises long after the injury has healed. They should become part of your usual training routine.