Sinding-Larsen-Johansson Syndrome

Sinding-Larsen-Johansson syndrome is a painful knee condition characterized by pain below the kneecap. It most commonly affects teens during periods of rapid growth (between 10 and 15 years of age).

Sinding-Larsen-Johansson syndrome is caused by placing repetitive or excessive stress on the kneecap that is still maturing resulting in an inflammatory response. Some of the factors that contribute to Sinding-Larsen-Johansson syndrome include increased participation in sports involving jumping and running, weak or tight quadriceps muscles, increased or improper training and activities that put more stress on the knees such as lifting heavy objects, walking up and down stairs, etc.

The symptoms of Sinding-Larsen-Johansson syndrome include pain in the front of the knee and near the bottom of the kneecap that increases with exercise or activities (running, climbing stairs, or jumping) and becomes more severe when kneeling or squatting. You might also experience swelling and tenderness around the kneecap.

Diagnosis of Sinding-Larsen-Johansson syndrome is done by reviewing your medical history and performing a thorough physical examination. Your doctor may also order other tests including an x-ray or magnetic resonance imaging (MRI) to rule out problems such as an infection or fracture.

Treatment includes rest, applying ice for 15-20 minutes every few hours, supporting your knee with a brace, band, or strap and keeping your knee higher than your heart to control swelling. Your doctor may prescribe medications to relieve pain and swelling. A stretching and strengthening program is recommended to improve strength and flexibility of the knees once your symptoms are under control.