Finite Element Analysis of Optimal Positioning of Femoral Osteotomy in Total Hip Arthroplasty With Subtrochanteric Shortening.

Background: Total hip arthroplasty with femoral shortening is frequently recommended for patients with high hip dislocation. However, the possibility of postoperative rotational deviation of the stem presents a challenge for surgeons. We aimed to determine the optimal position for osteotomy in total hip arthroplasty under full weight-bearing and turning torque by using finite element analysis.

Finite element analysis of double-plate fixation using reversed locking compression-distal femoral plates for Vancouver B1 periprosthetic femoral fractures.

Background: Internal fixation is recommended for treating Vancouver B1 periprosthetic femoral fractures. Although several fixation procedures have been developed with high fixation stability and union rates, long-term weight-bearing constructs are still lacking. Therefore, the aim of the present study was to evaluate the stability of a double-plate procedure using reversed contralateral locking compression-distal femoral plates for fixation of Vancouver B1 periprosthetic femoral fractures under full weight-bearing.

Design and optimization of the oriented groove on the hip implant surface to promote bone microstructure integrity.

We proposed a novel surface modification for an artificial hip joint stem from the viewpoint of maintenance and establishment of appropriate bone function and microstructure, represented by the preferred alignment of biological apatite (BAp) and collagen (Col). Oriented grooves were introduced into the proximal medial region of the femoral stem to control the principal stress applied to the bone inside the grooves, which is a dominant factor contributing to the promotion of Col/BAp alignment. The groove angle and the stem material were optimized based on the stress inside the grooves through a finite element analysis (FEA).