[Supra trochlear femoral erosions. Their relations with gonarthrosis and chondrocalcinosis (author's transl)].

Studying one hundred cases of simple gonarthrosis we found only one supra trochlear femoral erosion (STFE). Such a lesion was discovered in 14 cases among 150 chondrocalcinosis with arthrosic lesions. The cases involving STFE trend to a commun marked chondro-osteolytic evolution. The caracteristic patella sizes show clearly that STFE is not in relation with en anomaly of patella (patella alta...). The upper osteophyte of the patella presents only a minor importance in the formation of STFE. This STFE formation begins probably with a progressive chondro-osteolysis of patella and trochlea. Then, appears a progressive nipping between the upper point of patella and the supra trochlear femoral bone.