[Sinding-Larsen-Johansson disease: analysis of the associated factors].

AIM To analyse the clinical symptoms, aetiology and biomechanical aspects related to Sinding-Larsen-Johansson (SLJ) disease. MATERIAL AND METHOD A case control study was conducted, analysing the following variables: age, gender, clinical follow up, side of body with the symptoms, sporting activity, radiological stage, presence of patella alta, presence of short hamstring tendons, and increased posterior tibial slope. RESULTS A total of 15 knees in 14 patients were studied; one case with bilateral disease. The large majority of cases were 85.7% were male, and the mean age was 10.86 (standard deviation 1.61). All of them practised sport and physical activity at a high level with a variable duration of symptoms (1-36 months). There was predominance in side. The majority were radiological grade II (53.3). The data analysis did not show any significant difference (P>.05) between the study groups regarding the Caton and modified Insall indexes. There was a significant difference in the popliteal angle measured in the affected knees (mean: 32.50, SD: 8.9) compared with the control group (mean: 17.67, SD: 8.21). The difference in the posterior slope angle in the affected knees was also statistically significant (mean: 10.47, SD: 2.82) compared with the control (mean: 8.33, SD: 1.4). CONCLUSIONS According to our data, patients have short hamstring tendons and increased posterior tibial slope compared to the control group, and this difference is statistically significant.