The initial stress distribution in the femur after total hip arthroplasty (THA) influences the remodeling of the bone and the clinical results. We conducted thermoelastic stress analysis to evaluate the surface stress distribution in femurs after THA in vitro and elucidated the changes in the stress distribution that were due to the stem design. Using this method, we can analyze the change in the sum of the principal stresses on the basis of the changes in temperature at the bone surface and visualize the change three-dimensionally. We compared the thermoelastic stress analysis results with the clinical results of specially shaped stems that have two flanges, one anterior and one posterior.Introduction
Objectives
The goal of joint-preserving surgery for the treatment of osteonecrosis of the femoral head (ONFH) is to delay or prevent osteoarthritic development. Bone marrow is a source of osteogenic progenitors that are key elements in the process of bone formation and fracture healing. We established an easy-to-use method using a conventional manual blood bag centrifugation technique traditionally used for extracting buffy coats, for concentration of nucleated cells and platelets from clinical bone marrow aspirates to obtain osteogenic progenitors and growth factors. However, it is unclear whether the surgical goals are really achieved and if so in which patients. The purpose of this study was to identify demographic, clinical, and radiographic factors predicting total hip arthroplasty (THA) conversion after CABMAT for the treatment of idiopathic ONFH. We retrospectively reviewed 123 patients (213 hips) who had CABMAT between 2003 and 2010. Sixty-five subjects (115 hips) were male and 58 (98 hips) were female with an average age at the time of CABMAT of 40.1 years. Of the 213 hips, 143 hips in 78 patients had corticosteroid-induced ONFH, 46 hips in 27 patients had alcohol-associated, and 24 hips in 18 patients had no etiological factors could be detected. The mean follow-up period was 60.5 months. The endpoint of evaluation was set as the time point which the patient required additional surgery (THA) depending on the spontaneous hip pain, x-ray change, and social back ground. The following factors were investigated: age, sex, body mass index (BMI), unilateral or bilateral, etiological factors, preoperative classification and staging, visual analogue scale (VAS), JOA clinical score. The 213 hips were divided into two groups: a THA conversion (THA) group and a non-THA conversion (non-THA) group. A multivariate analysis was performed using a logistic regression model.Introduction
Methods
We used three-dimensional software to assess different anatomic variables in the femur. The canal of Femur twisted slightly below the lesser trochanter in cases with a larger angle of anteversion. Accurate positioning of the joint prosthesis is essential for successful total hip arthroplasty (THA). To aid in tailoring of the prosthesis, we used three-dimensional software to assess different anatomic variables in the femur.Summary Statement
Introduction
