Direct Anterior Approach For Total Hip Arthroplasty In The Lateral Decubitus Position:Early Clinical Results

Objective The direct anterior approach(DAA)for total hip arthroplasty(THA)is a true minimal invasive procedure through an intermuscular and interneural plane.However,this procedure in the lateral decubitus position is rarely reported in the literature.The purpose of this study is to evaluate the technical feasibility of DAA for THA in the lateral decubitus position,early clinical and radiographic outcomes and complications.Methods This study was a prospective,single arm,assessor blinded,observational trial.A total of 295 hips in 248 patients were recruited.According to inclusion criteria and exclusion criteria,126 hips underwent primary THAs through the DAA in the lateral decubitus position from July 1,2014 to June 31,2014.Complete data were obtained in 117 hips with 12?months follow?up and early clinical outcomes were assessed for primary THA using the DAA in the lateral decubitus position.Results The averaged duration of the operation was 72 minutes(range,50?160 minutes).The averaged intraoperative blood loss was 329 ml(range,185?655 ml).The Harris hip score was 53.2 points(range,44?65 points)preoperatively,82.1 points(range,74?90 points)at 1 month after surgery,86.0 points(range,79?95 points)at 3 months after surgery,and 88.6 points(range,80?96 points)at 12?month follow?up.Compared with the preoperative Harris hip scores,postoperative function scores significantly improved(p<0.001).Acetabular component was 16.5 ° ± 4.9 °anteversion and 43.3°±3.5°abduction.A total of 98 hips(83.8%)fell within the “safe zone”.The mean limb?length discrepancy was corrected from 11mm(0?22mm)preoperatively to 3mm(?5?15mm)postoperatively(Wilcoxon signed rank test,Z=?8.27,p<0.001).The lateral femoral cutaneous nerve injury was noted in 43 hips(36.8%).Intraoperative proximal femoral fracture occurred in one hip.The early dislocation occurred in two hips.Incomplete seating of the press?fit acetabular cup was found in three hips.No postoperative periprosthetic fracture and aseptic loosening occurred in our cases with 1?year follow?up.Conclusion The technical feasibility and safety of the DAA for THA in the lateral decubitus position was confirmed by clinical and radiographic outcomes in our early follow?up.Using the DAA with the patient in the lateral decubitus position instead of supine position may be a valuable alternative if a special operating room table or a traction table was absent,which is beneficial for the promotion of the DAA itself.