Sinding-Larsen Johansson Disease

Sinding-Larsen Johansson disease is one of the osteochondroses. It can be a cause of anterior knee pain. It is usually seen in a boy in his pre-teens. Pain is usually related to activity and is typically over the inferior pole of the patella. There is a separate article giving an overview of the Osteochondroses.

Osteochondroses all involve a defect in ossification. The mechanism in Sinding-Larsen Johansson disease is thought to be persistent traction at the cartilaginous junction of the patella and the patellar ligament/tendon (tendon and ligament are interchangeable terms here), usually at inferior patellar pole.¹ It is essentially a chronic stress injury with overuse of the patella-patellar tendon junction.² Similar symptoms can sometimes occur proximally, at the junction of the quadriceps tendon and the patella.³

• Activity related anterior knee pain
• On examination there is inferior patella tenderness

• Patella avulsion fractures
• Patella stress fracture
• Bipartite patella (type I)
• Osgood Schlatter's disease
• Jumper's knee is considered in older adolescents; Sinding-Larsen Johansson disease is the adolescent equivalent of Jumper's knee²

• Knee X-ray: can show calcification or ossification at the junction between the patella and the patella ligament
• MRI can be used^4,5

• Physiotherapy is the mainstay of treatment, including quadriceps strengthening exercises.
• Surgery is not usually needed.

• As the skeleton matures, symptoms usually improve and in this way it is regarded as a self-limiting process. However, symptoms may be present for at least a year.
• A case report has presented a case of a pathological patellar fracture through the site of an old Sinding-Larsen Johansson lesion.⁶