Patellar tendon tear

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The patellar tendon is responsible for connecting the patella to the shin bone. Generally, the patellar tendon is a vital part of the extensor mechanism of the lower extremity. The extensor mechanism is comprised of the quadriceps tendon, quadriceps muscle as well as the patellar tendon and kneecap. Take note that these structures enable the knee to straighten out and can do so with substantial strength.

Tendon tear

Athletic individuals are prone to end up with a torn patellar tendon. Since many middle-aged individuals stay physically active, this injury is becoming quite common in the older population.

In most cases, the injury involves an awkward landing from a jumping position in which the quadriceps muscle is contracting, but the knee is straightened out forcefully. This is called an eccentric contraction and puts tremendous stress on the tendon.

Causes of a torn patellar tendon

Athletic individuals are prone to end up with a torn patellar tendon.

Almost all individuals who sustain a patellar tendon rupture involve an unusual tendon tissue that is quite similar with chronic tendinosis. It is important to bear in mind that the patellar tendon is typically damaged in the area where blood flow to the tissue is inadequate and the tendon is at its weakest.

The tendon tears can also occur in non-athletic settings. Usually, the patellar tendon is weakened due to a systemic disease or a recent surgery on the knee.

Diagnosing a patellar tendon tear

A diagnosis of a torn patellar tendon is quite evident on clinical examination. Individuals who have a torn tendon might be unable to extend their knee against gravity and could not perform a straight leg raise test. In addition, there is a gap in the tendon, right below the kneecap.

An X-ray is requested since a patellar fracture can cause comparable symptoms and must be ruled out as a possible diagnosis. On the X-ray result, the patella is usually higher when compared to the opposite knee while the quadriceps pulls up on the kneecap and there is nothing holding it down. Even though not required, an MRI can be used to confirm a diagnosis and assess the knee for other damage that might have occurred.

Management of a torn patellar tendon

A patellar tendon tear does not heal properly on its own and if not treated, it can lead to weakening of the quadriceps muscles and the individual will have difficulty in performing daily activities including walking. Surgery to restore the damaged tendon is quite straightforward but can be hard to carry out.

The damaged ends of the tendon are sewn together. It is also essential to restore proper tension to the tendon, by ensuring that it is not too tight or too slack.


The recovery from a damaged patellar tendon is a tedious process and takes a certain time frame. A vital factor for the recovery is the time of surgery. If the surgery is delayed for a few weeks, it can reduce the recovery ability. Take note that early mobility after surgery, prevention of excess strain on the repair and safe strengthening can hasten the recovery.

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