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7. Sinding-Larsen-Johansson Disease

Sinding-Larsen-Johansson Disease (Patellar Tendonitis)

What is Sinding-Larsen-Johansson Disease?

Sinding-Larsen-Johansson Disease is an irritation of the growth plate at the bottom of the knee cap. The thigh muscles and tendon can become very tight and cause stress on the knee cap. This can occur in growth spurts or overuse from running, jumping or squatting.

What are the symptoms?

•  Knee pain, tenderness, and decrease in flexion, and/or swelling at the front of the knee near the bottom of the kneecap
• Pain with activity (especially running, jumping or squatting)
• Pain with bending the knee
• Soreness in the knee with long periods of sitting
• A bump on the bottom of the knee cap (see image above)
• Increase pain when kneeling

How is a diagnosis made?

•  X-ray
• Clinical exam

What is the treatment?

•  Activity modification
• Quadriceps and hamstring stretching
• Ice after activity
• Over the counter pain reliever
• Knee brace for comfort

How long do the symptoms typically last?

Six to twelve months. 

What is the timeline for follow-up?

•  Initial visit
• Four weeks
• As needed

Will this affect the knee in the future?

At this time there is not any correlation to having future knee problems.