Related Experiment Video
Updated: Apr 29, 2026
Three-Dimensional Preoperative Virtual Planning in Derotational Proximal Femoral Osteotomy
Published on: February 17, 2023
A study of collared prostheses and proximal femoral dimensions
Insights
Traditional total hip replacement placement challenges, specifically stem valgus positioning, were investigated. Findings suggest nonvarus positioning may be more appropriate for optimal collar placement on the femoral neck.
Area of Science:
- Orthopedic surgery
- Biomedical engineering
Background:
- Challenges in traditional collared total hip arthroplasty stem placement, leading to valgus positioning and collar overhang on the femoral neck.
- Review of existing data (Oh and Harris) used for HD2 device design.
Discussion:
- Comparison of HD2 design data with cadaveric specimens (n=21) and radiographic data from total hip arthroplasty patients (n=104).
- Analysis of hip size variations between different patient populations (Kentucky vs. Boston).
Key Insights:
- Identified similarities in hip dimensions between Kentucky and Boston patient cohorts.
- Questioned the emphasis on valgus positioning in total hip arthroplasty.
Outlook:
- Proposed that nonvarus stem positioning is potentially more suitable for accurate collar placement.
- Suggests a re-evaluation of current surgical techniques and implant design considerations for total hip replacement.
Abstract:
Difficulty has been encounterd in placing traditional collared total hips so the stem is in a valgus position and the collar is covering the cut portion of the femoral neck. We reviewed the data of Oh and Harris, which was used in designing the HD2 device, and compared these with actual specimens of 21 cadavers and x-rays of 104 Kentucky patients who received total hips. We found that the sizes of hips in Kentucky patients were exactly the same as those on patients in Boston, Massachusetts. We feel that valgus is perhaps overemphasized, and a nonvarus is more appropriate with the collar on the cut portion of the femoral neck.
