Combined Anteversion Adjusted to Native Anatomy Improves Functional Outcomes in Total Hip Arthroplasty: A...

The alignment of the femoral with the acetabular components significantly influences the mechanics of the hip joint, especially in total hip arthroplasty (THA). Combined anteversion (CA) is a combination of femoral neck anteversion and acetabular anteversion (AA). CA is emerging as a significant factor that influences optimal THA outcomes. Our study aims to assess the impact of CA on postoperative functional outcomes in an Indian cohort where unique lifestyle demands may influence the anteversion characteristics.

A retrospective study was conducted on 88 patients undergoing THA. Inclusion criteria included patients with unilateral THA due to femoral neck fractures or osteonecrosis of the femoral head. Computed tomography scans were used to identify and measure postoperative CA. We assessed the functional outcomes following THA at 7 days, 6 weeks, 3 months, 6 months, and 1 year, using the Harris hip score (HHS).

Our findings indicate that the CA values ranged from 25.5° to 93.9°, with a mean of 59.3°±15.7°. Patients with CA between 40° and 70° exhibited significantly improved functional outcomes, with an improvement in the mean HHS from 67.57 at day 7, to 94.26 at 3 months, to 97.50 at 1 year (P<0.001). In contrast, CA below 40° or above 70° was associated with poor outcomes, which includes a high risk of dislocation in the group with >70° CA.

Our study concludes that achieving a CA within the range of 40° to 70° is pivotal for optimal functional outcomes and for minimum complications in THA.