Osteologic standardization of human coxarthrosis using histomorphometry and its relevance for HIP alloarthroplasty.

Using bone histomorphometry, in this study the osteologic status of 107 patients with coxarthrosis and femoral neck fracture [FNF] was assessed and compared with bone parameters from patients revised for aseptic loosening. Bone biopsies of the acetabulum and the proximal femur from patients with primary coxarthrosis [pCoxA] (69), dysplastic coxarthrosis [CDH] (19), rheumatoid arthritis [RA] (9), femoral head necrosis [FHN] (8), femoral neck fracture [FNF] (4) and aseptic loosening (12) were taken during hip alloarthroplastic surgery, prepared undecalcified and analysed using histomorphometry (according to MERZ). In pCoxA the following average figures of bone parameters of the acetabular biopsy were determined: trabecular bone volume (TBV) 39.6%, osteoid volume (OV) 3.9%, active osteoblastic surface (AOS) 6.5%, osteoclastic resorption surface (ORS) 2.4%, osteoid surface (OS) 17.4% and resorption surface (RS) 7.0%. As average figures of the femoral biopsy in pCoxA were assessed: TBV = 17.2%, OV = 1.3%, AOS = 0.9%, ORS = 0.4%, OS = 6.5% and RS = 2.5%. These data were compared with bone parameters of secondary coxarthrosis, osteoporosis (FNF) and aseptic loosening. Based on the study of Oettmeier et al. on femoral heads (Skel Radiol 18: 165-174, 1989), the investigated groups were subdivided into three osteologic types of the hip. The osteopenic type was found in 10% of pCoxA, 43% of RA and 28% of CDH. The hyperostotic type, predominantly occurring in males, was mostly demarcated in FHN (38%) and pCoxA (12%). The results demonstrate the individual osteologic status of patients before hip alloarthroplasty. This could influence planning of the operation and the bone-implant interface as well as long-term prognosis of artificial joints.