Clinical study on posterior approach incision length in minimally invasive total hip arthroplasty / 中华创伤杂志

ABSTRACT

Objective To explore the reasonability of posterior approach incision length in an unselected patient cohort with minimally invasive total hip arthroplasty (THA) and compare the clinical results of different incision lengths. Methods A consecutive unselected 256 patients who underwent primary unilateral THA between March 2001 and December 2007 were studied prospectively. Prior to the operation, the incision length was not deliberately selected for the patients. A posterior approach was used for all procedures with minimally invasive surgical techniques. The patients were divided into three groups according to the incision length at the end of surgery mini-incision group ( ＜ 10 cm, 99 patients) , moderate incision group (10-14 cm, 112 patients) and standard incision group ( ＞ 14 cm, 45 patients). The in-hospital data including age, sex, diagnosis,body mass index (BMI),operation duration, intraoperative blood loss, total blood loss, preservation of the external rotators, anatomic repair of the capsule as well as postoperative radiographs were collected for analysis of the intraoperative and postoperative complications. The pain was estimated by using the individual visual analog scale (VAS) and the functional outcome evaluated by Harris hip score preoperatively and postoperatively. Results All the patients were followed up for an average period of 6.1 years (2.5-9.2 years). The incision length was shortened and optimized ( ＜ 14 cm) in 211 patients. There showed decrease of BMI, less intraoperative blood loss, less pain, satisfactory outcome but higher proportion of abnormal abduction angle of the acetabular prosthesis in the early postoperative period in the mini-incision group, with statistical difference compared with the other two groups (P ＜ 0.05). The preservation of the piriformis tendon, anatomic repair of the joint capsule, operation duration and Harris score at 6th postoperative week in the moderate incision group were similar to those in the mini incision group but showed statistical difference in comparison with the standard incision group ( P ＜0. 05). Conclusions Minimally invasive THA with a smaller posterior incision can attain safe and effective curative effect for the unselected patient cohort. A smaller but not necessarily miniincision may allow minimal soft tissue trauma for the surgeon to perform the procedure well and ensure a long-term clinical results.