Knee > Jumper's Knee

What is the Patellar Tendon?

The patellar tendon, which is actually a ligament and not a tendon, connects the kneecap to the shinbone (tibia). Patellar tendinitis, commonly known as "jumper's knee," is inflammation of the patellar tendon, where it connects the kneecap to the shinbone. It can also be a degenerative process in which microscopic partial tearing of the tendon occurs.

The patellar tendon, which is actually a ligament and not a tendon, connects the kneecap to the shinbone (tibia). Patellar tendinitis, commonly known as "jumper's knee," is inflammation of the patellar tendon, where it connects the kneecap to the shinbone. It can also be a degenerative process in which microscopic partial tearing of the tendon occurs.

Patellar tendinitis is usually caused by overuse in jumping and lunging activities because contraction of the thigh muscles (quadriceps) puts stress on the patellar tendon. Activities such as basketball, tennis, volleyball, high-jumping, and kicking are common causes of patellar tendinitis. The repeated stress of jumping and straightening the knee can cause the thigh muscles to be overused, making the patellar tendon absorb more of the shock of movement. This can cause the ligament to become stretched and to suffer microscopic tears, which in turn leads to irritation and inflammation, which in most cases causes pain. Eccentric loading is believed to be the root of the cause of patellar tendinitis. Eccentric loading occurs when a muscle is stretching and contracting at the same time, which happens when a person jumps - the muscles around the knee stretch yet also tighten to absorb the shock of landing. Misalignment of the kneecap, sudden increases in jumping and lunging activity, and inflexible thigh muscles and hamstrings can also contribute to patellar tendinitis. Inflexible thigh muscles force the patellar tendon to be subjected to more friction during movement.

If left untreated, symptoms can increase from one stage to the next as activities provoke and worsen the condition. However, it is extremely rare for patellar tendinitis to lead to a patellar tendon rupture. Without treatment, simple things such as standing or sitting for prolonged periods of time can lead to pain and stiffness. Activities can become increasingly difficult as pain infringes upon your performance.

There are usually three parts to an orthopedic evaluation: medical history, physical examination, and tests your physician may order.

Your physician likely will ask about your activities, some of which may be causing the pain in your knee. He will probably ask when the soreness and/or pain began, and if you've had any prior knee injuries.

Your physician will feel around the area of the patellar tendon to see if you have tenderness there. He may have you run, jump and squat to see if this causes pain. The flexibility of the quadriceps and hamstrings may be tested, with the doctor lifting your leg and bending your knee while you lay on your back.

TESTS

X-rays of your knee may be taken so that the physician can see the alignment of your kneecap, which could be causing or aggravating the problem. He may also request that you have a CT (computed tomography) scan, commonly referred to as a CAT scan, or MRI (magnetic resonance imaging), both of which will reveal bone, cartilage or muscle problems that may be the cause of the condition. Arthroscopy, in which the doctor inserts a tiny camera into your knee, might also be used so that the physician can actually look at the kneecap and the tendon. This is done on an outpatient basis, does not usually cause pain, and may be done under general or local anesthesia.

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