Patellar Tendonitis: Symptoms & Stages

Instructor: Dan Washmuth

Dan has taught college Nutrition, Anatomy, Physiology, and Sports Nutrition courses and has a master's degree in Dietetics & Nutrition.

Patellar tendonitis is a common injury to the knee that involves pain and inflammation of the patellar tendon. In this lesson, learn about the symptoms and various stages of patellar tendonitis.

Patellar Tendonitis

Brent is a 43-year-old teacher who frequently plays pick-up basketball games at this local community gym. Lately, Brent has been having a lot of pain in his left knee and this pain gets much worse while he plays basketball, especially when he is jumping and running.

Worried about this pain, Brent decides to go to his doctor to get his knee examined. At the doctor's office, Brent goes through several different tests to determine the cause of the recent knee pain. After evaluating the test results, the doctor informs Brent that he has patellar tendonitis.

Patellar tendonitis is a common injury of the knee that involves pain and inflammation of the patellar tendon. The knee joint is formed by the joining of the lower part of the femur (thighbone) and the upper part of the tibia (shinbone). The patella (kneecap) is a circular bone that moves along the front of the knee joint and is connected to the tibia by the patellar tendon.

The patellar tendon connects the patella to the tibia to help form the knee joint.
knee joint

Patellar tendonitis is an overuse injury, meaning it is the result of repetitive movements of the knee such as running and jumping. Long distance runners and basketball players frequently get patellar tendonitis due to the constant movement of their knee joints from all the running and jumping required in their respective sports. This constant running and jumping can cause the patellar tendon to become irritated and inflamed, resulting in patellar tendonitis.

Patellar tendonitis is often caused by frequent running or jumping such as when a person plays basketball.

Patellar Tendonitis: Symptoms

The most common symptom of patellar tendonitis is pain. This pain usually increases when a person moves the knee joint such as during walking, running, and jumping. Other symptoms of patellar tendonitis include:

  • Swelling
  • Stiffness
  • Tenderness
  • Weakness

The most common symptom of patellar tendonitis is knee pain.
knee pain

Patellar Tendonitis: Stages

There are four main stages of patellar tendonitis:

  • Stage I: Pain associated with the patellar tendonitis occurs only after exercising or activity.
  • Stage II: Pain occurs both during and after exercising or activity, but the pain does not impact or limit performance or activities.
  • Stage III: Pain in the knee is constant and the pain starts to limit or negatively impact performance and activities.
  • Stage IV: The patellar tendon actually tears or ruptures.

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