Bone mineral density in the femoral neck increases after hip resurfacing: a cohort with five-year follow-up

Abstract

Hip resurfacing is an effective treatment modality for arthritis of the hip in carefully selected patients; however, its use remains controversial due to its higher revision rates compared with conventional total hip replacement surgery. The most frequent reason for revision is femoral neck fracture, and preoperative bone mineral density is an important factor when considering the option of hip resurfacing. Whilst reduction in bone mineral density following total hip replacement is well documented, little is known about the long-term changes in femoral neck bone mineral density after hip resurfacing. We followed 15 patients (ten male and five female) who underwent unilateral hip resurfacing for osteoarthritis with standardised dual energy X-ray absorbiometry scans at two weeks, three months, one year, two years and five years postoperatively to determine changes in the femoral neck bone mineral density. Both males and females initially had decreases in bone mineral density at three months postoperatively, but had gradual mean increases to 119% of their initial measurements by five years. This study demonstrates that femoral neck bone mineral density increases after hip resurfacing and that this increase continues for at least five years.

Prediction of Bone Mineral Density (BMD) Adaptation in Pelvis–Femur Model with Hip Arthroplasties

“…However, the increment in BMD in the continuing years, as reported in other studies, [ 29 , 30 , 31 ] was in contrast to this study. A minimal reduction was expected in the following years, similar to that projected in the hip OA and THA femurs.…”

“…As the resurfacing techniques involved the modification of the femoral head and neck, the proximal region of the femur was expected to experience more changes. Willis-Owen et al [ 29 ] reported that the BMD of the femoral neck only decreased in the first three months, and then kept increasing for at least five years. A comparison study between THA and RHA by Kishida et al [ 30 ] also found an increase in BMD in Gruen 1 and 7 following hip arthroplasty, while there was a BMD reduction following total replacement for two years.…”

What should I expect from my recalled Adept Hip Resurfacing?

“…Proponents of HR advocate several advantages over standard total hip replacement (THR) which include: preservation of femoral bone stock which makes revision of the femoral side easier at a later date [2]; better stability because of the large head diameter [3]; less abnormal loading of the upper femur and femoral stress shielding [4]; superior functional outcome which allows high impact sport resumption; and higher survival in selected patients [5].…”

Is the increase in bone mineral density after hip resurfacing uniform across the femoral neck?

“…We admired the work of Willis-Owen and his colleagues on bone remodelling after hip resurfacing presented in their article "Bone mineral density in the femoral neck increases after hip resurfacing: a cohort with five-year follow-up" [1]. Hip resurfacing has evolved as an alternative to total hip arthroplasty in young adults and has shown promising short-and mid-term results when prudent selection criteria were adopted.…”