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 $\pm$ 6.16, 10.41 $\pm$ 3.62, and 95.19 $\pm$ 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.