Hemi- and total hip arthroplasty for avascular osteonecrosis of the femoral head

In literature, the results of hip arthroplasty in patients with avascular o steonecrosis of the femoral head vary. The main reason may be the nonhomoge neous patient groups concerning etiology of the femoral head necrosis (FHN) . Analyzing the results of hip endoprosthesis in relation to the etiology o f FHN leads to the assumption that steroid-induced FHN and FHN with underly ing systemic bone diseases (renal osteodystrophy, sickle-cell hemoglobinopa thy) have the highest loosening rates. Diseases with immunosuppressive medi cation and sickle-cell hemoglobinopathy have the highest risk of joint infe ction. Therefore etiology plays an important role in the long-term results of hip endoprostheses in FHN. Modern cement techniques of the second genera tion and new noncemented total hip endoprostheses seem to have better resul ts than older prostheses and cement techniques. We followed-up 52 noncement ed thrust plate prostheses in 45 patients with FHN, prospectively, for at l east 2 years (3.7 +/- 1.6 years). The revision rate was 9.6% (two aseptic l oosenings in one patient with renal osteodystrophy and one patient with alc ohol abuse, as well as three late infections in one patient with alcohol ab use and two patients with renal osteodystrophy). Additionally, five prosthe ses showed radiologic lines of a minimum of 2 mm. Future studies with longe r follow-up are needed to find out whether these prosthetic designs with pr oximal fixation of the femoral component preserving the diaphysial bone hav e advantages in young FHN patients.