Minimum 10-Year Outcomes of Double-Tapered Cemented Stems with Line-to-Line Cementing: A Comparative Study of Collared and Collarless Stems.

Background: This study aimed to evaluate the clinical and radiological outcomes of stems using the line-to-line technique with a minimum follow-up of 10 years.

Methods: A retrospective comparative study was conducted on 282 consecutive primary total hip arthroplasties (244 patients) using two cemented stem types at a single institution by a single surgeon from 1996 to 2011. Clinical and radiological assessments and stem survival analysis were performed.

Results: There were no significant differences in hip function outcomes or complication rates between the groups. The 10-year stem survival rate for any revision was 97.0% (95% CI [confidence interval]: 93.6 to 99.6) in stem group A and 99.0% (95% CI: 94.6 to 99.9) in stem group B, respectively (P = 0.279). Both groups had a 100% survival rate for aseptic loosening. Stem subsidence was more in stem group B (P < 0.001). Cortical hypertrophy occurred in 28.9 and 19.8% of the two groups, respectively, with good clinical outcomes in affected patients.

Conclusion: The 10-year clinical and radiological outcomes for stems using the line-to-line technique were excellent, with no revisions required for aseptic loosening.