Metal-on-metal hip resurfacing arthroplasty provides excellent long-term survivorship and function in patients with a good-sized femoral head

Abstract

Aims To establish the survivorship, function, and metal ion levels in an unselected series of metal-on-metal hip resurfacing arthroplasties (HRAs) performed by a non-designer surgeon. Methods We reviewed 105 consecutive HRAs in 83 patients, performed by a single surgeon, at a mean follow-up of 14.9 years (9.3 to 19.1). The cohort included 45 male and 38 female patients, with a mean age of 49.5 years (SD 12.5) Results At the time of review 13 patients with 15 hips had died from causes unrelated to the hip operation, and 14 hips had undergone revision surgery, giving an overall survival rate of rate of 86.7% (95% confidence interval (CI) 84.2 to 89.1). The survival rate in men was 97.7% (95% CI 96.3 to 98.9) and in women was 73.4% (95% CI 70.6 to 75.1). The median head size of the failed group was 42 mm (interquartile range (IQR) 42 to 44), and in the surviving group was 50 mm (IQR 46 to 50). In all, 13 of the 14 revised hips had a femoral component measuring ≤ 46 mm. The mean blood levels of cobalt and chromium ions were 26.6 nmol/l (SD 24.5) and 30.6 nmol/l (SD 15.3), respectively. No metal ion levels exceeded the safe limit. The mean Oxford Hip Score was 41.5 (SD 8.9) and Harris Hip Score was 89.9 (14.8). In the surviving group, four patients had radiolucent lines around the stem of the femoral component, and one had lysis around the acetabular component; eight hips demonstrated heterotopic ossification. Conclusion Our results confirm the existing understanding that HRA provides good long-term survival and function in patients with adequate-sized femoral heads. This is evidenced by a 97.7% survival rate among men (larger heads) in our series at a mean follow-up of 14.9 years. Failure is closely related to head sizes ≤ 46 cm. Cite this article: Bone Jt Open 2022;3(1):68–76.

Birmingham Hip Resurfacing at 20 years

“…The reasons for early failure in female patients have been discussed previously, 35 and are also described in long-term follow-up series with resurfacing designs, other than BHR. 36,37 Due to design issues that create a smaller arc of articulation in the small-sized components, and the greater range of motion achieved by female patients, the consequence is that female patients will more easily ‘find the edge’ of the articulation and more often create a high wear scenario. Among the revised hips in females, eight had femoral heads measuring 42 mm.…”

Hip resurfacing arthroplasty as an alternative to total hip arthroplasty in patients aged under 40 years

“…In 2021, Amstutz et al 36 conducted an investigation of 355 patients who underwent HRA, which demonstrated an 83.5% 20-year survivorship, indicating the long-term durability of the implant. In a separate study, Gani et al 37 investigated the long-term survivorship of 105 patients who underwent HRA, showing an 86.7% survivorship in a cohort with a mean follow-up of 14.9 years. In 2014, Daniel et al 22 reported a HRA revision rate of 3.8% with a mean follow-up of 13.7 years.…”

What’s New in Hip Replacement

“…In a recent single-surgeon cohort, Gani et al suggested that metal-on-metal hip resurfacing provides a durable intervention at a mean follow-up of 14.9 years (range, 9.3 to 19.1 years) for men receiving resurfacing implants with a head size of >46 mm 4 . The survivorship in this group was reported as 97.7%, with no metal ion level exceeding the accepted safe limits.…”