[Long-term results of the forage-biopsy in grade I and II osteonecrosis of the femoral head. Apropos of 133 cases re-examined after an average time of 9 years 6 months].

The results of 133 operations of cervical forage are reported with an average follow-up of 9 years. There were 94 p. 100 of good results in grade I cases and 82 p. 100 in grade II cases. The basis of the procedure is to produce a decrease of pressure in the venous circulation of the bone. The importance of early operation is stressed.