A Comparative Study Of Two Kinds Of Compound Internal Fixation For Treatment Of Nonunion Of Distal Femur

Objective:To compare the clinical outcomes of double plates(DP)versus retrograde intramedullary nail and plate(NP)combined with bone autografting in the treatment of nonunion after distal femoral fracture.Methods:A retrospective study was conducted on 29 patients who underwent surgical treatment for nonunion secondary to distal femur fractures in our hospital from January 2015 to September 2018.According to the consequences of preoperative doctor-patient communication,15 patients received DP while the remaining 14 patients were treated with NP.The two groups were compared regarding to the perioperative period,follow-up and imaging documents.Results:All the patients in both groups had the operations completed successfully with no serious complications,such as vascular and nerve damage during the operation.The NP group was significantly better than the DP group in terms of total hospital stay,postoperative drainage,total incision length,and intraoperative fluoroscopy(P<0.05),regardless of that no statistically significant differences were noted in operation time and intraoperative blood loss between the two groups(P>0.05).The NP group recovered walking [(30.21±3.85)days versus(33.47±3.94)days,P<0.05] and full weight-bearing activity [(24.00±4.24)weeks versus(30.20±6.95)weeks,P<0.05]significantly earlier than the DP group.Compared with those preoperatively,the knee extension-flexion ROM,the HSS scores,as well as the shortening and varus deformities of the lower extremities were significantly improved(P<0.05).However,there were no statistically significant differences between the two groups in terms of knee HSS score,corrections of lower extremity shortening deformity and varus deformity at the latest follow-up between them(P>0.05).Regarding imaging evaluation,there was no significant difference in the quality of fracture reduction between the two groups(P>0.05),but the NP group got fracture healing significantly earlier than the DP group(P<0.05).To the latest follow-up,no internal fixation loosening or breakage happened in anyone of them.Conclusion:Both surgical techniques do achieve satisfactory clinical outcomes for nonunion secondary distal femoral fractures.In contrast,the clinical outcomes of NP are better than DP.