ABSTRACT
UNLABELLED: To evaluate the physicochemical characteristics of lyophilized bovine grafts manufactured on a semi-industrial scale (Orthogen; Baumer S/A*) in accordance with a protocol previously developed by the authors. METHODS: The lyophilized bovine bone grafts were characterized by means of scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), X-ray diffractometry (XRD), thermogravimetric (TG) analysis, differential exploratory scanning calorimetry (DSC) and Fourier-transform infrared (FT-IR) spectroscopy. RESULTS: Ca was the main component (60%) found in the samples, followed by P (28%) and O (5%). The mean (sd) pore size was 316 µm (146.7), ranging from 91.2 to 497.8 µm, and 333.5 µm (304.8), ranging from 87.2 to 963.9 µm, at 50x and 150x magnification, respectively. The hydroxyapatite peaks were at 26°C and 32°C, and mass losses were observed between 250°C and 640°C, corresponding to organic material and water. Two temperature transitions (45.67°C and 91.89°C) showed denaturation of type 1 collagen and dehydration of hydroxyapatite. CONCLUSION: The physicochemical assessment of lyophilized bovine bone grafts in accordance with the protocol developed at semi-industrial scale confirmed that this product presents excellent biocompatibility, with characteristics similar to natural bone.
ABSTRACT
OBJECTIVE: To analyze the clinical and radiological outcomes from total hip arthroplasty using the Biomec prosthesis over a 20-year period (1988 to 2009). METHODS: The patients were evaluated clinically in accordance with the Merle d'Aubigné and Postel functional classification, and underwent anteroposterior (AP) radiography of the pelvis and the operated joint in lateral view. The variables evaluated were acetabular and femoral osteolysis, polyethylene wear, nail migration, follow-up and clinical outcomes. RESULTS: The mean follow-up was 10.6 years (range 4 to 21 years). The sample consisted of 84 patients (32 men and 52 women) and the mean preoperative age was 47 years. We found that 88% of the results from the clinical evaluation were good or excellent. In relation to the radiological findings, 92.5% of the results were good. The mean wear on the polyethylene was 1.4 mm. CONCLUSION: The use of the Biomec prosthesis in this cohort showed good clinical and radiographic results.
