Sinding-Larsen-Johansson: Kneecap Pain in Young Athletes
Does your child have pain at the base of the kneecap? SLJ syndrome is an apophysitis typical of ages 10-14. Diagnosis and treatment in Milan.
Quick Answers
What is the difference between Sinding-Larsen and Osgood-Schlatter?
How long does it last?
Does it leave permanent effects?
Sinding-Larsen-Johansson syndrome is essentially the "cousin" of Osgood-Schlatter: same mechanism, same age group, same prognosis — but the pain is located a few centimeters higher, at the base of the kneecap rather than below it.
Here's what happens: in athletes aged 10 to 14 doing intensive sports (especially soccer, basketball, volleyball), the patellar tendon repeatedly pulls on the lower pole of the kneecap, where the growth plate is still open. The result is local inflammation — an apophysitis — that presents as pain at the base of the kneecap, especially with jumping, running, or climbing stairs.
Like Osgood-Schlatter, SLJ always resolves with skeletal maturity: when the ossification center at the inferior patellar pole closes, the pain disappears for good. The course is similar — from a few months to a year, with alternating phases — and the treatment is identical: load management, quadriceps and hamstring stretching, progressive eccentric strengthening.
An interesting note: unlike Osgood-Schlatter, which may leave a small residual bony bump (painless), SLJ typically resolves without any visible trace.
When to seek evaluation
- Pain at the base of the kneecap during jumping or running
- Pain worsening going up/down stairs
- Tenderness at the lower pole of the kneecap
- Pain after intense sports activity
- Localized swelling at the base of the kneecap
What is evaluated
- Palpation of the inferior patellar pole
- Pain with resisted quadriceps contraction
- Muscle flexibility assessment (quadriceps, hamstrings)
- Differential diagnosis with Osgood-Schlatter and patellar tendinopathy
- X-ray or ultrasound in selected cases
Treatment options
- Activity modification (reduction, not cessation)
- Quadriceps and hamstring stretching
- Progressive eccentric strengthening
- Ice after activity (15 min)
- Infrapatellar strap in symptomatic cases
- Gradual return to sports
Frequently Asked Questions
What is the difference between Sinding-Larsen and Osgood-Schlatter?▼
How long does it last?▼
Does it leave permanent effects?▼
Other Juvenile Osteochondroses
Osteochondroses are a family of growth-related conditions. Learn about the others:
Important Notice: The information on this page is for educational and informational purposes only and does not constitute medical advice. Each clinical case is unique: the appropriate treatment is determined during the specialist consultation, based on a thorough clinical examination and, where necessary, diagnostic imaging. For any doubts or concerns, please consult a specialist.
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Email: daniele.priano@ortopediaevolutiva.com
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