Long-Term Survival Outcomes of Wagner™ Conical Stems in Crowe Non-IV Hip Dysplasia: A Retrospective Analysis

Fabio D'Angelo^1,2*Andrea Pautasso²Delia Antognazza²Luca Monestier²Mattia Gervasini³Marco Filipponi⁴Chiara Bernardi³Giacomo Riva²

• ¹University of Insubria, Department of Biotechnology and Life Sciences, Varese, Italy
• ²Aziende Socio Sanitarie Territoriale dei Sette Laghi, Varese, Italy
• ³Universita degli Studi dell'Insubria, Varese, Italy
• ⁴Ospedale Vito Fazzi, Lecce, Italy

Background: Total hip arthroplasty (THA) is one of the most frequently performed orthopedic procedures. Developmental dysplasia of the hip (DDH) presents specific anatomical challenges that require tailored implant designs. Wagner™ conical stems were developed to address the morphological alterations of dysplastic femur, offering potential advantages in stability and functional restoration. This study assesses the long-term survival and clinical outcomes of Wagner™ conical stems in patients with Crowe non-IV DDH. Materials and Methods: This retrospective study included primary THAs performed between 2003 and 2015 using Wagner™ conical stems exclusively in patients with DDH. Only cases with complete clinical and radiographic follow-up were analyzed, excluding those lost to follow-up or revised. The evaluated outcomes were prosthetic survival rate, clinical performance assessed with the Modified Harris Hip Score (mHHS), and radiographic findings at final follow-up. Results: Forty-five patients (57 hips) met the inclusion criteria. The mean age at surgery was 56.5 years (range, 33–76), with a mean follow-up of 15 years (range, 8–20). Kaplan–Meier analysis showed a survival rate of 95.7% at 10 years and approximately 80.5% at 20 years, with an overall survival rate of 89.5% at the final follow-up. The main cause of failure was aseptic loosening, followed by infection, recurrent dislocation, and metallosis. Among hips with retained implants, 86.3% (44/51) achieved an mHHS >70, indicating satisfactory functional recovery. The mean mHHS was 88.6 +- 14.3 (Range, 62–100), with a median of 92 and a mode of 100. Conclusion: Wagner™ conical stems provide durable fixation and favorable long-term functional outcomes in Crowe non-IV DDH, with high survival rates and low complication incidence over extended follow-up.