Direct anterior versus posteriorlateral approachs for clinical outcomes after total hip arthroplasty in the treatment of severe DDH

The total hip arthroplasty (THA) has gained popularity in in the treatment of severe developmental dysplasia of the hip (DDH). the posterior lateral approach (PLA) has good clinical efficacy and has been confirmed by the majority clinicians. Nevertheless, controversy exists regarding longer-term benefits of the direct anterior approach (DAA). The objective of this study was to investigate the clinical efficacy and placement of S-ROM prosthesis in the treatment of severe DDH by The total hip arthroplasty (THA) with different surgical approaches.A retrospective analysis was performed on 42 patients with severe DDH admitted to our hospital from August 2015 to February 2022, who were treated with S-ROM prosthesis for total hip arthroplasty and subtrochanteric osteotomy of the femur. They were divided into DAA group and PLA group according to different surgical approaches. Perioperative indicators and imaging data were collected.The surgery time, intraoperative blood loss, and creatine kinase difference in DAA group and PLA group was without a statistically significant difference (P > 0.05). The postoperative length of hospitalization was shorter in the DAA group than in the PLA group (6.50 ± 3.15 vs 9.18 ± 4.93, P = 0.045). The acetabular abduction angles、the acetabular anteversion angles, the safe area ratio, The difference of femoral eccentricity, and the vertical difference of rotation center in DAA group and PLA group, there was no statistical significance (P > 0.05). Statistically significant differences were detected the horizontal difference of rotation center (P = 0.044).Total hip arthroplasty with S-ROM prosthesis is a feasible procedure for severe dysplastic DDH. The clinical efficacy and prosthesis placement parameters of DAA approach are advantage to those of PLA approach.