A Comparative Study Of The Short Term Clinical Efficacy Of Total Hip Arthroplasty Performed With A Direct Anterior Approach Versus The Traditional Posterolateral Approach

Objective: To compare the short term clinical efficacy of total hip arthroplasty performed with a direct anterior approach versus the traditional posterolateral approach.Methods: Based on operative approach,the 47 patients,who received the initial total hip arthroplasty(THA)in the Second Hospital Affiliated to Dalian Medical University between April 2014 and June 2015,were randomly divided into two groups: DAA Group and PLA Group.There were 21 patients and 22 hips in DAA Group,while 26 patients and 27 hips in PLA Group.For DAA Group,there were 5 male patients with 5 hips,and 16 female patients with 17 hips;the average age: 68.9 ± 1.6(66-73);avascular necrosis of femoral head(stage III and IV): 16 hips;femoral neck fracture(Garden III and IV): 6 hips;the average body mass index(BMI): 23.3±0.8Kg/m2(16.0~29.6 kg/m2);preoperative Harris scores: 36.3±2.3(18.0~56.0).For the PLA Group,there were 7 male patients with 7 hips,and 19 female patients with 20 hips;the average age: 67.5±1.7(62~78);avascular necrosis of femoral head(stage III and IV): 18 hips;femoral neck fracture(Garden III and IV): 9 hips;the average BMI: 22.7±0.8Kg/m2(17.0~29.8kg/m2);preoperative Harris scores: 37.6±2.4(21.0~54.0).Inclusion criterions for patients:(1)BMI ≤30kg/m2(2)Initial THA(3)No severe deformity in hip bony structure(4)avascular necrosis of femoral head(stage III and IV)(5)femoral neck fracture(Garden III and IV)(6)patient age ≥ 60 years old.Exclusion criterions:(1)BMI > 30kg/m2(2)severe osteoporosis(3)previous operation on hip joints(4)severe dysplasia in acetabulum(Crowe Ⅲ and Ⅳ).The experiment conducted prospective comparison of the two groups of THA patients who received the operation by the same physician through 2 different approaches for the first time.According to examination results of the two groups of patients,there was no significantly statistical difference between the DAA Group and the PLA Group in sex,age,diagnosis,BMI and preoperative hip Harris scores.Besides,comparative analysis was made of the length of surgical incision,operation duration,intraoperative blood loss,length of hospital stay,postoperative Harris scores and the incidence of complication between the two groups of patients.Results:6-month postoperative follow-up visit was conducted among the 47 patients.All the patients experienced primary wound healing,without joint infections or dearticulation.The DAA group averaged the surgical incision length of 9.2 ± 0.2cm(8.0 ~ 11.0),while the PLA group 14.7 ± 0.5cm(12.0 ~ 17.0).Compared with the PLA group,the DAA group experienced shorter surgical incision length,with statistically significant difference(p<0.01).The DAA group averaged the operation duration of 106.7 ± 1.7 minutes(89 ~ 121),while the PLA group 90.6 ± 1.3 minutes(78 ~ 102).The DAA group experienced longer operation duration than the PLA group and there was statistically significant difference(p<0.01).The DAA group saw the intraoperative blood loss of 309.1±12.6ml(262~408)on average,while the PLA group 465.1±14.1ml(368~523)on average.The DAA group saw less intraoperative blood loss than the PLA group,and there was statistically significant difference(p<0.01).There were 6 cases of intraoperative femoral fracture to the DAA group,but none to the PLA group.The DAA group experienced higher incidence of intraoperative femoral fracture than the PLA group,with statistically significant difference(p<0.05).There were 8 cases of injury to lateral femoral cutaneous nerve during the operation;however,no injury to lateral femoral cutaneous nerve occurred to the PLA group during the operation.The DAA group experienced higher incidence of intraoperative injury to lateral femoral cutaneous nerve than the PLA group,with statistically significant difference(p<0.01).The DAA group averaged the hospital stay of 10.5 ± 0.7 days(5-18),while the PLA group 12.9 ± 0.8 days(6-21).The PLA group stayed longer in hospital than the DAA group,and the difference was statistically significant(p<0.05).At 6 weeks following the operation,the DAA group saw the average Harris score of 76.0 ± 0.9(70.0 ~ 82.0),while the PLA group 69.2 ± 1.3(56.0 ~ 81.0).In terms of Harris score 6 weeks following the operation,the DAA group performed better than the PLA group.The difference was statistically significant(p<0.01).At 3 weeks following the operation,the DAA group saw the average Harris score of 87.0 ± 0.8(78.0 ~ 92.0),while the PLA group 83.9 ± 0.9(76.0 ~ 90.0).The DAA group performed better than the PLA group,and the difference was statistically significant(p<0.05).In terms of Harris score 6 weeks following the operation,the DAA group averaged 92.6 ± 0.7(86.0 ~ 97.0)and the PLA group 91.0 ± 0.7(82.0 ~ 95.0).There was no statistically significant difference in Harris score 6 weeks following the operation between the two groups of patients(p>0.05).Conclusions:1.As a kind of minimally invasive THA surgical approach,DAA causes small incision,less blood loss and less soft tissue invasiveness.Besides,there is no postoperative postural restriction,which is conducive to early function rehabilitation.2.Both DAA and PLA are favorable THA surgical approaches,and satisfactory recovery is achieved among patients half year following operation.However,DAA sees shorter hospital stay and faster functional recovery during the early postoperative stage(within 3 months).3.DAA features long learning curve and higher complication incidence during the early stage.