KNEE FUNCTIONAL OUTCOME AND ASSOCIATED FACTORS AMONG PATIENTS TREATED WITH RETROGRADE INTRAMEDULLARY NAIL FOR FEMORAL SHAFT FRACTURE AT ADDIS ABABA BURN EMERGENCY AND TRAUMA HOSPITAL, ADDIS ABABA, ETHIOPIA

Abstract

Abstract Background: Intramedullary nailing is currently preferred method of treating femoral shaft fracture as it provides stable fixation with excellent union rate. The need for better functional outcome with knee rehabilitative protocols in such patients continues to be discussed. However, the results are not thoroughly established in the current study setting, where intramedullary nailing is common management option and knee functionality remains to be quantified. Objective: The aim of this study was to assessing the knee functional outcome and associated factors following retrograde intramedullary nailing of traumatic femoral shaft fractures at Addis Ababa Burn Emergency and Trauma Hospital, Addis Ababa, Ethiopia. Methods: An institution-based, cross-sectional study was conducted among 148 consecutive patients from January 1st, 2015 through December 31st, 2021. Knee functional outcome was assessed using the Hospital for Special Surgery scoring system (HSS) at least one year after the operation. Data were entered and analyzed using SPSS version 26. Descriptive analysis was used to present the preoperative and postoperative characteristics while ordinal logistic regression was run to identify factors associated with functional outcome. A p-value <0.05 was considered significant. Texts, tables and figures were used to present the results. Results: A total of 148 patients were studied; of these, males predominated (n=122;82.4%). Patients' median age was 30 years (interquartile range, 24.25–40). Patients' Hospital for Special Surgery score mean ± standard deviation was 85.6 ± 11.0 (range, 41–94). Overall, functional outcomes were classified as excellent in 53.4%, good in 39.2%, fair in 3.4% and poor in 4.1%. Ordinal logistic regression analysis indicated that age < 30 years (OR=19.80, p value<0.001), age 30 to 45 years (OR=11.9, p value=0.002), absence of comorbidity (OR=4.50, p value=0.002), road traffic accident (OR=5.57, p value=0.019), history of wound site infection (OR=0.15, p value<0.001), and postoperative physical therapy (OR=0.40, p-value=0.039) were the factors significantly associated with poor functional outcome in these patients. Conclusion: Retrograde nailing is associated with favourable knee functional status in our patient population. It is associated with age, comorbidity, mechanism of injury, wound site infection, and postoperative physical therapy. Thus, use of retrograde techniques should be encouraged whenever appropriate. Keywords: Knee functional outcome, Retrograde intramedullary nail, Hospital for Special Surgery scoring system, Associated factors, Ordinal logistic regression