Knowledge of low back hygiene rules by teachers of physical education and sport in Cotonou

outcome was favorable and X-rays confirmed the fracture healing. Discussion.– This is the first description of a proximal tibia fracture after ankle arthroplasty. This fracture occurred near a total knee prosthesis in patient with hemophilia. Hemophilic patients may suffer from increased risk of a secondary fracture following an osteoporosis [2], but it is not the case here. The cause of this atypical fracture remains unknown (local bone fragility associated with hemophilia? Alteration of bone strength near the total knee arthroplasty?). This clinical case highlights the absolute need to exclude a fracture when recent mechanical pain, even in cases of atypical location. References [1] Glazebrook MA. 2009;30:945–9. [2] Wallny TA. 2007;13:79–84.