A prospective randomized study comparing the direct anterior approach in the lateral decubitus position versus the standard posterolateral approach for total hip arthroplasty

Abstract

There have been a large number of studies comparing the direct anterior approach (DAA) in the supine position with the standard posterolateral approach (PLA) for total hip arthroplasty (THA). However, there have been few studies on DAA in the lateral decubitus position (LDAA). Therefore, this prospective randomized study was conducted to compare the early clinical, laboratory and radiological outcomes between patients who underwent the LDAA or the PLA for THA.

Seventy-two patients were randomly divided into two groups. The patients in one group accepted THA via the LDAA, and the patients in the other group accepted THA via the PLA. All operations were performed by an experienced  orthopedic surgeon, who is skilled in both approaches. All preoperative and postoperative data were collected by other well-trained researchers. The data collected included length of incision, operation time, intraoperative blood loss, post-operation drainage, length of stay, orientation of acetabular component, position of femoral prosthesis, complication rates, perioperative transfusion rates, serum creatine kinase (CK), serum C-reactive protein (CRP), serum  myoglobin (MYO), postoperative hemoglobin (HGB), visual analogue scores (VAS), and Harris hip scores (HHS).

Compared with the PLA, the LDAA offered the benefits of shorter incision (P < 0.001), less intraoperative blood loss (P < 0.001), less postoperative drainage (P < 0.001), and shorter length of stay (P < 0.001). In addition, the LDAA caused lower levels of CK, CRP, and MYO and higher levels of postoperative HGB. The LDAA group received a lower score (P < 0.001) in the VAS and a higher score (P < 0.001) in the HHS. However, the LDAA required a longer operation time than the PLA (P < 0.001). No significant differences were found in complication rates, perioperative transfusion rates, orientation of the acetabular component, or the position of femoral prosthesis between the two groups.

Compared with the PLA, our results showed that for THA, the LDAA is more minimally invasive, and the patients in the LDAA group achieved a faster functional recovery with less muscle damage and better pain relief.