Minimally invasive small incision direct anterior total hip arthroplasty in the lateral decubitus position: complications and early outcome

Abstract

Objective: To analyze the feasibility, perioperative complications and early outcomes of minimally invasive small incision in direct anterior approach total hip arthroplasty in lateral decubitus position. Methods: From January 2015 to January 2017, 212 patients (228 hips) received minimally invasive small incision (approximately 8 cm in length) direct anterior approach total hip arthroplasty in modified lateral decubitus position and approach. Sixteen cases underwent bilateral hip arthroplasty separately. All procedures were performed by the same surgeon in the Department of Orthopedics, the First Affiliated Hospital of University of Science and Technology of China, Anhui Provincial Hospital. Twenty-eight patients (28 hips) were set as the complicated case group. The rest 184 patients (200 hips) had no previous hip surgeries, severe deformity and limited motion of the hip, were set as the standard group, and were divided into the first 100 cases group and the second 100 cases group in sequence. The difference between the standard group and complicated case group were analyzed. Also we compared the difference between the first 100 cases and the second 100 cases. Perioperative complications, postoperative function and radiological evaluation were recorded and statistically analyzed. The t test was applied to compare the data between groups. Results: All the patients were followed-up for 13 to 25 months[(18±5) months]. Intraoperative complications and postoperative complications happened in 9 and 34 patients respectively. The anterior dislocation occurred in 2 cases. The standard group showed significant superior outcomes when compared with complicated case group in the surgical time[(42±19) vs (67±16) min, t=-2.628, P=0.027], blood loss[(222±94) vs (579±120) ml, t=-8.371, P=0.000], postoperative Harris hip score[90±5 vs 83±7, t=2.390, P=0.024]and the rate of surgical complication (15.0% vs 46.4%, χ(2)=15.854, P=0.000). The complication rate tended to decrease in the second 100 cases when compared with that in the first 100 cases (11.0% vs 19.0%, χ(2)=3.922, P=0.037). Meanwhile, the second 100 cases showed significant excellent outcomes when compared with the first 100 cases in the mean surgical time[(34±15) vs (48±10) min, t=4.217, P=0.002]and blood loss[(182±52) vs (254±40) ml, t=2.889, P=0.018]. Conclusions: It suggests that there is a learning curve with the minimally invasive small incision direct anterior approach total hip arthroplasty in lateral decubitus position. The risk of intraoperative femoral fractures is slightly high, especially for cases with osteoporosis, stiffness and limited range of movement. Surgeons in early learning curve period should grasp the surgical indications and master the technical points.