Concomitant sickle cell disease and skeletal fluorosis

Skeletal fluorosis typically manifests as a diffuse increase in bone density, whereas avascular necrosis of the epiphyses and diaphyseal marrow are the main skeletal manifestations of sickle cell disease. The diagnostic and therapeutic challenges raised when both disorders are present are illustrated by two cases in Senegalese patients from an area characterized by high fluoride contents in the water and soil. Both had SS sickle cell disease. Skeletal fluorosis was diagnosed during evaluation for avascular necrosis in one patient and in the wake of septic arthritis in the other. Femoral head necrosis is difficult to identify in a patient with skeletal fluorosis. The bone lesions due to sickle cell disease and those due to fluorosis can mimic other bone diseases, most notably metastases. The combination of sickle cell disease and fluorosis results in significant medullary canal narrowing due to cortical thickening and to accumulation of necrotic bone. When performing hip replacement surgery, careful reaming of the medullary canal may reduce the risk of iatrogenic femoral fracture and inappropriate stem placement.