AAOS2018: 20-year results of serum cobalt, radiographic, and clinical outcome between MoM & CoP THA

Study Type: Randomized Trial
OE Level of Evidence:
Journal Level of Evidence: N/A
Serum Cobalt Levels after Metal-on-Metal and Ceramic-on-Polyethylene Total Hip Arthroplasty: A Randomized-Controlled Study with a Minimum Follow Up of 20 Years
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100 patients scheduled for total hip arthroplasty were randomized to metal-on-metal or ceramic-on-polyethylene articulation.A total of 20 patients were available for follow-up after 20 years.Patients were assessed for serum cobalt levels, radiographic outcomes, and clinical outcome on the Harris Hip Score.Median cobalt level among patients treated with MoM articulation was 1.04ug/L, and a total of two patients required reoperation due to metallosis. HHS after 20... Please login to view the rest of this report. Please login to view the rest of this report.

Why was this study needed now?

Few randomized controlled trials comparing outcomes of different bearing surfaces in total hip arthroplasty have described follow-up into the long-term, particularly 20 years after surgery. This study sought to compare serum metal ion concentrations, clinical outcomes, and radiographic outcomes between metal-on-metal total hip arthroplasty and ceramic-on-polyethylene total hip arthroplasty.

What was the principal research question?

In total hip arthroplasty, how do serum cobalt concentrations, clinical scores, and radiographic measures compare after 20 years between metal-on-metal and ceramic-on-polyethylene bearing surfaces?
Population: 100 patients scheduled for cementless total hip arthroplasty with a 28mm femoral head. (n=20 available after 20 years; Mean age: 69 [42-97])
Intervention: MoM group: Total hip arthroplasty was completed with metal-on-metal articulation (n=50; 11 available after 20 years)
Comparison: CoP group: Total hip arthroplasty was completed with ceramic-on-polyethylene articulation (n=50; 9 available after 20 years)
Outcomes: Outcome measures included serum cobalt concentrations, the clinical outcome on the Harris Hip Score, and radiographic outcomes, including the incidence of osteolysis development.
Methods: RCT
Time: Follow-up was reported to be a minimum of 20 years postoperatively.

What were the important findings?

What should I remember most?

How will this affect the care of my patients?

The authors responsible for this critical appraisal and ACE Report indicate no potential conflicts of interest relating to the content in the original publication.