Survivorship and radiological analysis of a monoblock, hydroxyapatite-coated titanium stem in revision hip arthroplasty

Abstract

Background: We evaluated the survivorship, incidence of complications, radiological subsidence, proximal stress shielding, and patient-reported outcomes of a conservative, monoblock, hydroxyapatite-coated femoral stem.

Methods: This retrospective cohort study reports on 254 revision hip arthroplasties between January 2006 and June 2016. The mean age of patients was 71 years. The mean length of follow-up was 62 months (range 12-152).

Results: There were 13 stem re-revisions: infection (4), periprosthetic fracture (4), aseptic stem loosening (3), stem fracture (1), and extended trochanteric osteotomy nonunion (1). Kaplan-Meier aseptic stem survivorship was 97.33% (confidence interval 94-100) at 6 years. There were 29 intraoperative fractures. There were 6 cases of subsidence greater than 10 mm; however, none required revision. Ninety-six percent of cases showed no proximal stress shielding. Thigh pain was reported in 3% of cases.

Conclusion: This study confirms that this stem provides good survivorship at 6 years, acceptable complication rates, adequate proximal bone loading, low incidences of thigh pain, and reliable clinical performance in revision hip arthroplasty.

Key message: A monoblock, fully hydroxyapatite-coated titanium stem is reliable in revision arthroplasty with mild-moderate femur deficiencies.