A Prospective Cohort Study On The Clinical Outcome Of Direct Anterior Approach In Total Hip Arthroplasty

Objective:To study the clinical data of patients after direct anterior approach(DAA)total hip arthroplasty(THA),and compare it with posterolateral approach(PLA)THA.To evaluate the efficacy and safety of direct anterior approach total hip arthroplasty(DAA-THA)in clinical application,and to provide the best surgical solution for patients with total hip arthroplasty.Methods:A prospective cohort study was conducted.202 patients who received THA in Mianyang Central Hospital from January 2018 to October 2019 were divided into exposure group(DAA group)and non-exposure group(PLA group)according to whether they received DAA-THA or not.The outcomes of the two groups were observed,and t test,Mann-Whitney U test,x~2 test or Fisher exact probability method were used to analyze the observation indexes between the two groups(operation index:operation time,intraoperative blood loss,postoperative drainage;laboratory index:hemoglobin,albumin;imaging index:acetabular anteversion angle and abduction angle,femoral stalk-medullary axis angle,femoral offset,leg length discrepancy;complications:dislocation,anterolateral thigh numbness or pain,femoral fracture,infection,deep venous thrombosis,mortality;other index:hospitalization time,functional score),the outcome differences between the two groups were compared.Result:(1)There was no significant difference in age,sex,BMI,operation and disease type between the two groups(P>0.05).(2)Comparison of operative indexes:operation time:DAA group(126.74±35.62)min was higher than PLA group(58.56±12.05)min;Intraoperative blood loss:DAA group(204.31±140.53)ml was less than PLA group(263.86±83.72)ml;Postoperative drainage volume:DAA group(225.94±97.89)ml was lower than PLA group(303.47±78.30)ml,the differences were statistically significant(P<0.05).(3)Comparison of laboratory indexes:the difference of hemoglobin before and after operation:DAA group(24.55±9.26),PLA group(26.49±10.98);the difference of albumin before and after operation:DAA group(10.04±3.09),PLA group(10.15±4.10),with no significant difference(P>0.05).(4)Comparison of imaging indexes:the acetabular anteversion angle:DAA group(13.52±5.41)°,PLA group(13.76±6.20)°;Acetabular abduction Angle:DAA group(41.41±6.76)°,PLA group(42.63±4.56)°;86.14%of the acetabulum in the DAA group was in the Lewinnek safety zone,while 84.16%of the acetabulum in the PLA group was in the Lewinnek safety zone,with no statistically significant difference(P>0.05).The included Angle between femoral stalk and medullary cavity axis:DAA group(2.10±1.15)°was larger than PLA group(1.63±1.20)°,the difference was statistically significant(P<0.05).The femoral prosthesis in the DAA group was 88.12%with central fixation,while the femoral prosthesis in the PLA group was 92.08%with central fixation,showing no statistically significant difference(P>0.05).Femoral offset difference:DAA group(5.32±4.19)mm,PLA group(6.31±5.17)mm;The femoral prosthesis in the DAA group was 88.12%with central fixation,while the femoral prosthesis in the PLA group was 92.08%with central fixation,the difference was not statistically significant(P>0.05).The difference in the leg length discrepancy(LLD):DAA group(5.12±3.87)mm,PLA group(5.75±4.50)mm;the rate of LLD(>10mm):the rate of LLD of DAA group was 7.92%,and that of PLA group was 14.85%,with no significant difference(P>0.05).(5)Comparison of complications:dislocation:0 cases in DAA group,5 cases in PLA group;femoral fracture:3 cases in DAA group and 1 case in PLA group;LLD(>10mm):8 cases in DAA group and 15 cases in PLA group;postoperative periprosthetic fractures:1 case in the DAA group and 0 cases in the PLA group,with no statistically significant difference(P>0.05),lateral thigh complications:27 cases in DAA group and0 cases in PLA group,the difference was statistically significant(P<0.05);there were no incisional or periprosthetic infection,no cases of deep venous thrombosis and no death caused by operation-related causes.(6)Comparison of other indexes:hospitalization time:DAA group(7.48±2.01)d was lower than PLA group(9.29±2.26)d,and the difference was statistically significant(P<0.05).Harris hip function score increased gradually before and after operation and 1,3 and 6 months after operation,and there was significant difference between the two groups(P<0.05).Preoperative score of DAA group(40.22±14.08)was lower than that of PLA group(42.93±10.63),with no statistically significant difference(P>0.05);1month after surgery,the score of DAA group(79.74±5.84)was better than that of PLA group(72.10±4.30);3 months after surgery,the score of DAA group(87.48±2.33)was better than that of PLA group(85.72±4.45);6 months after surgery,the DAA group(94.06±3.23)score was superior to the PLA group(92.50±1.95)score,with statistically significant differences(P<0.05).Conclusion:DAA-THA has the advantages of less surgical injury,more accurate placement of prosthesis,low dislocation rate,short hospitalization time,quick postoperative recovery and good early recovery.DAA-THA can be used as the best surgical solution for patients with total hip arthroplasty and can provide better surgical results for both doctors and patients.