Anatomical cup implantation assisted with dynamic 3D planning improves functional outcomes in primary total hip arthroplasty: A retrospective study

Abstract

BACKGROUND: Anatomical cup implantation is a promising approach in primary total hip arthroplasty (THA) and improves functional outcomes. OBJECTIVE: We aimed to evaluate the cup position and functional outcomes in primary THA with preoperative dynamic 3D planning. METHODS: We retrospectively reviewed 54 hips in 48 patients who underwent primary THA with anatomical cup implantation (mean follow-up time: 52 months). Cup positions were evaluated based on patient-specific morphology, the acetabular fossa and the combined anteversion test. Functional outcomes were assessed after THA. The paired-sample t-test was performed for surgical and contralateral native hips among 42 patients who underwent unilateral THA. RESULTS: Two hips suffered intraoperative trochanteric fracture, but no hip dislocations occurred. No patients reported groin or thigh pain, and all patients were capable of deep squatting and one-leg standing. The mean Harris hip score, WOMAC score, and physical SF-36 score were 94.46 ± 6.16, 10.41 ± 3.62, and 95.19 ± 8.74, respectively. Except for acetabular offset, THA restored biomechanics to those of contralateral native hip, including cup anteversion, abduction, femoral offset and acetabular height (P> 0.05). CONCLUSION: This study provided evidence for the application of anatomical cup implantation assisted with dynamic 3D planning in primary THA, which restored morphology and improved functional outcomes.