Bone resorption of the proximal femur is a frequent complication of total hip replacement. As hip resurfacing (HR) may load the bone more physiologically, we measured proximal femur bone mineral density (BMD) in 21 patients with HR. DEXA analysis was performed in the 7 Gruen zones and in the femoral neck pre-operatively and at 3, 9, and 24-months post-operatively. In Gruen zone-2 the BMD ratio ...

Sir—We read with interest the paper of Alm et al. (2009). The authors looked at post-total hip arhtroplasty periprosthetic (THA) bone changes in 39 subjects using DXA to analyse bone mineral density (BMD) in the Gruen zones surrounding the femoral prosthesis component. The purpose of the study was to look for factors such as bone mineral status that might influence femoral periprosthetic bone l...

INTRODUCTION The purpose of the current study was to investigate the reaction of the femur to the implantation of the MiniHipTM in terms of: (1) bone density change during one year; (2) correlations between stem length, CCD (caput-collum-diaphyseal), femoral offset, T-value, and bone density; (3) other co-variables that influence the change of bone density. PATIENTS AND METHODS MiniHipTM impl...

progressive loss of bone mineral density around the femora! component of total hip replacement continues to pose a threat to long term prosthetic survival. a linear study was undertaken to measure bone mineral density on a monthly basis following total hip arthroplasty in 11 male patients. the opposite femur was used as the control measurement. bone mineral density was unchanged at two months f...

BACKGROUND AND PURPOSE Customized femoral stems are designed to have a perfect fit and fill in the femur in order to achieve physiological load transfer and minimize stress shielding. Dual-energy X-ray absorptiometry (DXA) is regarded as an accurate method for detection of small alterations in bone mineral density (BMD) around hip prostheses. We present medium-term DXA results from a randomized...

Alterations in bone strain as a result of implantation may contribute towards periprosthetic bone density changes after total hip arthroplasty. Computational models provide full-field strain predictions in implant-bone constructs; however, these predictions should be verified using experimental models wherever it is possible. In this work, finite element predictions of surface strains in intact...

A prospective radiostereometric analysis (RSA) study of 18 patients with cemented revision hip surgery and impaction grafting with an Exeter stem was done with a follow-up of 2 years for all patients. All factors that could influence migration (ie, micromotion) of the stem were analyzed with a repeated measurements analysis of variance. Two groups could be identified: a stable group and a conti...

An analysis of the cement mantle obtained with the Exeter impaction allografting system at one centre showed that it was either deficient or absent in almost 47% of Gruen zones. We therefore examined the mantle obtained using this system at another hospital and compared the results with those from the CPT and Harris Precoat Systems at other centres. The surgical indications for the procedure an...

Peri-prosthetic bone loss caused by stress shielding may be associated with aseptic loosening of femoral components. In order to increase primary stability and to reduce stress shielding, a three-dimensional, cementless individual femoral (Evolution K) component was manufactured using pre-operative CT scans. Using dual energy x-ray absorptiometry, peri-prosthetic bone density was measured in 43...