Hip resurfacing can be a good alternative to total hip replacement (THR) in young adults because it conserves bone and it has acceptable short- to medium-term results. However, there have been concerns about fractures of the femoral neck with this procedure, partly due to notching and varus alignment during implantation.
Therefore, in this study the author’s used imageless computer navigation as a method to aid in the placement of the femoral component in hip resurfacings. Pre-operative templating was used to determine the planned stem-shaft angle against the native neck-shaft angle. Post-operatively, this template was then assessed using digital anteroposterior unilateral radiographs of the hip.
There were no instances of notching of the femoral neck or varus alignment of the implant. The stem-shaft angle differed from that planned by 2.8° and while ‘a learning curve was observed in the time taken for navigation’ this was not true for accurate placement of the implant.’
The author’s conclude that ‘computer navigation for placement of the initial guidewire in hip resurfacing has been shown to be more accurate than the use of conventional mechanical jigs’ and that it ‘shows promise in optimising the preparation of the femoral head’ and in helping to reduce factors that can cause the femoral neck to fracture and the implant to fail.
Source: The Journal of Bone and Joint Surgery