Autologous impaction bone grafting of a cemented acetabular component in primary total hip arthroplasty in young patients: a randomized controlled trial.

AIMS: This randomized controlled trial (RCT) aimed to compare clinical and radiological outcomes of cemented acetabular component in primary total hip arthroplasty (THA) in patients aged under 60 years with and without autologous impaction bone grafting (IBG).

METHODS: A single-centre, triple-blinded RCT was conducted in patients aged 18 to 59 years undergoing primary THA without acetabular defects. Patients were randomized to receive either IBG or no IBG. Noninferiority of IBG was assessed for the primary endpoint, the Hip disability and Osteoarthritis Outcome Score (HOOS) sub-scale for activities of daily living (ADL) at one-year follow-up. Secondary outcomes included other patient-reported outcome measures (PROMs), perioperative outcomes, complications, and radiological outcomes. Radiographs assessed acetabular component and centre of rotation positioning, offset changes, and the presence of radiolucent lines in the bone-cement interface.

RESULTS: A total of 131 patients were randomized. No significant group differences were found for the HOOS-ADL sub-scale at one year (mean difference 1.9 points (95% CI -4.85 to 8.7); p = 0.578), meeting the criteria for noninferiority. Furthermore, there was no effect of group on the scores for other PROMs. Surgery duration (+ 7.5 minutes; p < 0.001) and blood loss (+ 100 ml; p = 0.001) were significantly higher in the IBG group. Complication and revision rates were comparable. Radiologically, the IBG group had significantly fewer radiolucent lines in the bone-cement interface than the control group at one-year follow-up (p < 0.001). Compared with preoperatively, the postoperative position of the centre of rotation was less superior and medial in the IBG group (p = 0.024).

CONCLUSION: The use of autologous IBG with a cemented acetabular component in primary THA in young patients is noninferior to standard cemented fixation regarding short-term clinical outcomes. IBG improves vertical position of the centre of rotation and early radiological fixation by reducing radiolucent lines around the cup, suggesting potential benefits for long-term acetabular component survival.