Clinical Application Of Modified Retractor System In Total Hip Arthroplasty (THA) Via Direct Anterior Approach(DAA)

Objectives:To evaluate the clinical utility of a modified retractor system in total hip arthroplasty(THA)via the direct anterior approach(DAA)in the supine position.Methods:Sixty patients who were admitted by the Second Affiliated Hospital of Nanchang University and underwent DAA THA during June 2018 and July 2019 were recruited in this study and divided into a control group(n =30)and an observation group(n=30)using a random number table.Hoffman retractors were used for DAA THA in the control group,while our hospital’s modified retractor system was applied in the observation group to observe the duration of operation(Do O),intraoperative blood loss(IBL),length of stay(Lo S),Harris Hip Scale(HHS)scores at the first,third,and sixth month after operation,visual analog scale(VAS)scores before operation and on day 1,3,5,and 10 after operation,and serological markers such as C-reactive protein(CRP),interleukin-6(IL-6),and creatine kinase(CK)on day 1,3,5 after operation,and The incidence of postoperative complications was compared.Results:(1)The observation group(121.59±6.98)min and the control group(120.32±6.95)min showed no significant difference in Do O(P >0.05).(2)The observation group was(7.12±1.05)days had an Lo S shorter than the control group(9.85±1.69)days,and the difference was statistically significant(P <0.05).(3)The IBL level in the observation group(53.29±7.94)ml was significantly lower than in the control group(84.12±8.81)ml(P <0.05).(4)Compared with the control group(40.72±3.83 points),the observation group(45.15±4.03 points)had a higher HHS score a month after operation,and the difference was statistically significant(P<0.05),whereas three and six months later,the differences in HHS score between the two groups no longer exhibited statistical significance(P >0.05).(5)On day 1,3,5,and 10 after operation,the VAS scores in both groups were markedly lower than the preoperative levels(P <0.05,respectively),and the observation group scored significantly lower compared with the control group after operation(P <0.05,respectively).(6)On day 1,3,and 5 after operation,the CRP,IL-6,and CK levels in the observation group were significantly lower than in the control group(P <0.05).(7)In the observation group,there was a case of postoperative complication,specifically lateral femoral cutaneous nerve injury,representing 3.33% of the total DAA THA cases;two cases of postoperative complications were reported by the control group,including a case of lateral femoral cutaneous nerve injury with palsy and the other as incisional wound infection,accounting for 6.67% of all patients.The differences in postoperative complications between the two groups showed no statistical significance(P >0.05).Conclusions(1)The modified retractor system can effectively reduce intraoperative blood loss,relieve pressure on the assistant,and assist with the exposure of the operative field for DAA THA in the supine position.(2)The modified retractor system also helps prevent muscle injury,ease postoperative pain,lower the levels of inflammatory factors and stress and support postoperative recovery.Therefore,the modified retractor system is worthy of wider clinical applications.