A low-cost solution for the restoration of femoral head centre during total hip arthroplasty

Proc Inst Mech Eng H. 2013 Jun;227(6):629-35. doi: 10.1177/0954411913482438. Epub 2013 Apr 4.


Restoration of joint centre during total hip arthroplasty is critical. While computer-aided navigation can improve accuracy during total hip arthroplasty, its expense makes it inaccessible to the majority of surgeons. This article evaluates the use, in the laboratory, of a calliper with a simple computer application to measure changes in femoral head centres during total hip arthroplasty. The computer application was designed using Microsoft Excel and used calliper measurements taken pre- and post-femoral head resection to predict the change in head centre in terms of offset and vertical height between the femoral head and newly inserted prosthesis. Its accuracy was assessed using a coordinate measuring machine to compare changes in preoperative and post-operative head centre when simulating stem insertion on 10 sawbone femurs. A femoral stem with a modular neck was used, which meant nine possible head centre configurations were available for each femur, giving 90 results. The results show that using this technique during a simulated total hip arthroplasty, it was possible to restore femoral head centre to within 6 mm for offset (mean 1.67 ± 1.16 mm) and vertical height (mean 2.14 ± 1.51 mm). It is intended that this low-cost technique be extended to inform the surgeon of a best-fit solution in terms of neck length and neck type for a specific prosthesis.

Keywords: Total hip arthroplasty; calliper; femoral head restoration.

MeSH terms

  • Anthropometry / instrumentation*
  • Anthropometry / methods
  • Arthroplasty, Replacement, Hip / instrumentation*
  • Arthroplasty, Replacement, Hip / methods*
  • Computer Simulation
  • Femur Head / anatomy & histology*
  • Femur Head / surgery*
  • Humans
  • Imaging, Three-Dimensional / methods*
  • Models, Anatomic*
  • Models, Biological*
  • Reproducibility of Results
  • Sensitivity and Specificity
  • Surgery, Computer-Assisted / methods*