What is the common demographic affected by Sinding-Larsen-Johansson syndrome?

Sinding-Larsen-Johansson syndrome primarily affects boys aged 8 to 12 years, making this demographic particularly susceptible due to their increased physical activity and participation in sports during these formative years. This condition is characterized by pain and inflammation at the inferior pole of the patella, often caused by repetitive stress on the knee during activities such as jumping and running.

The choice of this age group is significant because it coincides with the peak growth phase in children, where they are more prone to overuse injuries due to rapid growth and increased physical demands. This condition is an example of an overuse injury that usually resolves with rest and appropriate management. The affliction is less common in older adolescents or adults, as by that age, the growth plates have typically closed and the risk factors associated with this syndrome diminish. The other demographics listed do not align with the typical presentations for Sinding-Larsen-Johansson syndrome, thus reinforcing the specificity of the affected age group.