Anterior femoral erosion and patello-femoral osteoarthritis.

: The relationship between classical signs of osteoarthritis, anterior femoral erosion, and patellar tendon lengths was determined in 130 patients derived from a sports medicine clinic and a general hospital. A method for detecting and measuring anterior lower femoral erosion is described. A significant relationship was found between anterior femoral erosions and osteoarthritis, but no significant relationship was found between patellar tendon length and osteoarthritis. The results bring into question previously described explanations for femoral erosions. It is suggested that this erosion is due to pressure transmitted from the supra-patellar bursa in active patients with joint effusions.