Patellar tendinitis is a relatively common cause of pain in the inferior patellar region in athletes. It is common with frequent jumping and studies have shown it may be associated with stiff ankle movement.

Presentation

Jumper's knee (patellar tendinopathy, patellar tendinosis, patellar tendinitis) commonly occurs in athletes who are involved in jumping sports such as basketball and volleyball. Patients report anterior knee pain, often with an aching quality. The symptom onset is insidious. Rarely is a discrete injury described. Usually, involvement is infrapatellar at or near the infrapatellar pole, but it may also be suprapatellar.

Depending on the duration of symptoms, jumper's knee can be classified into 1 of 4 stages, as follows:

Stage 1 – Pain only after activity, without functional impairment
Stage 2 – Pain during and after activity, although the patient is still able to perform satisfactorily in his or her sport
Stage 3 – Prolonged pain during and after activity, with increasing difficulty in performing at a satisfactory level
Stage 4 – Complete tendon tear requiring surgical repair

It begins as inflammation in the patellar tendon where it attaches to the patella and may progress by tearing or degenerating the tendon

Tendon

A tendon is a tough band of fibrous connective tissue that usually connects muscle to bone and is capable of withstanding tension. Tendons are similar to ligaments and fasciae as they are all made of collagen except that ligaments join one bone to another bone, and fasciae connect muscles to other...

. Patients present with an ache over the patella tendon. Most patients are between 10 and 16 years old. Magnetic resonance imaging can reveal edema

Edema

Edema or oedema ; both words from the Greek , oídēma "swelling"), formerly known as dropsy or hydropsy, is an abnormal accumulation of fluid beneath the skin or in one or more cavities of the body that produces swelling...

 (increased T2 signal intensity) in the proximal aspect of the patellar tendon.

Causes

It is an overuse injury from repetitive overloading of the extensor mechanism of the knee

Knee

The knee joint joins the thigh with the leg and consists of two articulations: one between the fibula and tibia, and one between the femur and patella. It is the largest joint in the human body and is very complicated. The knee is a mobile trocho-ginglymus , which permits flexion and extension as...

. The microtears exceed the body's healing mechanism unless the activity is stopped.

The injury occurs to athletes in many sports including baseball

Baseball

Baseball is a bat-and-ball sport played between two teams of nine players each. The aim is to score runs by hitting a thrown ball with a bat and touching a series of four bases arranged at the corners of a ninety-foot diamond...

 (catcher), bowling

Bowling

Bowling Bowling Bowling (1375–1425; late Middle English bowle, variant of boule Bowling (1375–1425; late Middle English bowle, variant of boule...

, golf

Golf

Golf is a precision club and ball sport, in which competing players use many types of clubs to hit balls into a series of holes on a golf course using the fewest number of strokes....

 (reading putts), association football, rugby

Rugby football

Rugby football is a style of football named after Rugby School in the United Kingdom. It is seen most prominently in two current sports, rugby league and rugby union.-History:...

, volleyball

Volleyball

Volleyball is a team sport in which two teams of six players are separated by a net. Each team tries to score points by grounding a ball on the other team's court under organized rules.The complete rules are extensive...

, track & field, freerunning, tennis

Tennis

Tennis is a sport usually played between two players or between two teams of two players each . Each player uses a racket that is strung to strike a hollow rubber ball covered with felt over a net into the opponent's court. Tennis is an Olympic sport and is played at all levels of society at all...

, American football

American football

American football is a sport played between two teams of eleven with the objective of scoring points by advancing the ball into the opposing team's end zone. Known in the United States simply as football, it may also be referred to informally as gridiron football. The ball can be advanced by...

, basketball

Basketball

Basketball is a team sport in which two teams of five players try to score points by throwing or "shooting" a ball through the top of a basketball hoop while following a set of rules...

, lacrosse

Lacrosse

Lacrosse is a team sport of Native American origin played using a small rubber ball and a long-handled stick called a crosse or lacrosse stick, mainly played in the United States and Canada. It is a contact sport which requires padding. The head of the lacrosse stick is strung with loose mesh...

, ultimate frisbee, badminton

Badminton

Badminton is a racquet sport played by either two opposing players or two opposing pairs , who take positions on opposite halves of a rectangular court that is divided by a net. Players score points by striking a shuttlecock with their racquet so that it passes over the net and lands in their...

, diving

Diving

Diving is the sport of jumping or falling into water from a platform or springboard, sometimes while performing acrobatics. Diving is an internationally-recognized sport that is part of the Olympic Games. In addition, unstructured and non-competitive diving is a recreational pastime.Diving is one...

, skateboarding

Skateboarding

Skateboarding is an action sport which involves riding and performing tricks using a skateboard.Skateboarding can be a recreational activity, an art form, a job, or a method of transportation. Skateboarding has been shaped and influenced by many skateboarders throughout the years. A 2002 report...

, snowboarding

Snowboarding

Snowboarding is a sport that involves descending a slope that is covered with snow on a snowboard attached to a rider's feet using a special boot set onto mounted binding. The development of snowboarding was inspired by skateboarding, sledding, surfing and skiing. It was developed in the U.S.A...

, gymnastics

Gymnastics

Gymnastics is a sport involving performance of exercises requiring physical strength, flexibility, agility, coordination, and balance. Internationally, all of the gymnastic sports are governed by the Fédération Internationale de Gymnastique with each country having its own national governing body...

, Olympic weightlifting, powerlifting

Powerlifting

Powerlifting is a strength sport. It resembles the sport of Olympic weightlifting, as both disciplines involve lifting weights in three attempts. Powerlifting evolved from a sport known as 'odd lifts' which followed the same three attempt format but used a wide variety of events akin to Strongman...

, rope skipping and kickboxing

Kickboxing

Kickboxing refers to a group of martial arts and stand-up combat sports based on kicking and punching, historically developed from karate, Muay Thai and western boxing....

 dance.

Treatment

Early stages may be treated conservatively using the R.I.C.E

RICE (medicine)

RICE is a treatment method for soft tissue injury which is an acronym for Rest, Ice, Compression and Elevation. When used appropriately, recovery duration is usually shortened and discomfort minimized....

 methods.

1. Rest
2. Ice
3. Compression
4. Elevation

A physical therapist may also recommend specific exercises and stretches to strengthen the muscles and tendons. Should this fail, autologous blood injection

Autologous blood injection

Autologous Blood Injection , also known as Autologous Conditioned Plasma Injection is a recent medical procedure whereby a patient's blood is injected into an area of the body for the purposes of healing. It is most commonly used to treat degeneration of tendons, which may occur in association...

, or injection of platelet rich plasma may be performed and is typically successful though not as successful as high volume saline injection (Crisp et al.). Uncommonly it may require surgery to remove myxoid degeneration in the tendon. This is reserved for patients with debilitating pain for 6–12 months despite conservative measures. Novel treatment modalities targeting the abnormal blood vessel growth which occurs in the condition are currently being investigated.

External links

• Jumpers Knee & Acrobatics
• Patellar Tendinitis, Musculoskeletal Consumer Review
• Ultrasound images demonstrating patella tendinosis and an autologous blood injection
• Jumpers Knee Symptoms
• http://www.patellatendonitis.co.uk Information board