Short term outcome of patients with open tibia Diaphyseal fracture treated with external fixator at Muhimbili Orthoepedic Institute

Abstract

Title: Short term outcome of patients with open tibia diaphyseal fracture treated with external fixator at Muhimbili Orthoepedic Institute. Objective: To determine the short term treatment outcome of tibia diaphysial fractures treated with external fixator at MOI. Methodology: A prospective descriptive study done on adult patients 18 years and above with open tibial shaft fractures treated by AO tubular EF. This study was conducted at MOI for a period of twelve months from beginning April 2016 to the end of March 2017. Eighty patients met the inclusion criteria and were recruited after signing the informed consent. Data was collected using guided structured questionnaire including wound status, callus formation, malalignment and weight bearing stutus. Other tools like tape measure and goniometer were used to collect necessary information during follow up clinic at 2nd, 6th, 10th, and 12th week post-surgery. The obtained data for short term outcome were analyzed by SPSS version 20. Results During this study a total of 80 patients with open tibial shaft fractures were enrolled and followed up. The proportion of open tibia diaphyseal fractures among all open fractures was found to be 7.2 %. Of these 80 patients males were 69(86.2%) and females 11(13.8%), with approximated male to female ratio of 6:1.The majority of patients were in the age group of 18-30 years (47.5%) with a mean age of (33.61 +/- 10.71) years. In this study motorcycles were the leading mechanism of injury, contributing 53 (66.2%) patients, followed by motor vehicles 23(28.8%), then falls from the height 4(5%) patients. In all these motor traffic crashes (76 patients), 38(50%) were passengers, 26(34.2%) drivers and 12 (15.8%) were pedestrians. Grade II fractures were most common 47 (58.8%) patients, followed by grade IIIA, 26(32.5%) patients, grade IIIB 6(7.5%) patients and least was grade I, 1(1.3%) patient. In these fracture the average time of initial callus formation visible on x ray was 10 weeks, it ranged from 6 weeks to 12 weeks ,with the mean RUST score of 7 at the end of the follow up. In this study, 7(8.8%) patients had superficial wound infection and 3(3.7%) had deep wound. Patients with grade III injury develop infection more (70%) compared to grade II injury (30%) and there were no wound infection in grade I. It was statistically significance that grade III fractures had high rate of infection compared to other grade with p-value of 0.031. Following the use of external fixator, 53(66.3%) develop pin tract infection. Duration of stay for the shantz pin in a patient affect the chance for pin tract infection, the longer it stay the higher the chance of infection. This was statistically significance under chi square test with P-value of less than 0.001 within 95% confidence interval. Out of 80 patients of study population 38 (47.5%) had malunion which include shortening (7.5%) and angular deformity (40%). Reoperation was planned for 22(27.5%) patients; malalignment(23.7%) and deep infection (3.8%) were the main cause. Conclusion Motor traffic crashes were the main cause of open tibia diaphyseal fractures. Younger population constitutes a larger number of the injured. Treatment of these fractures with AO tubular EF resulted in high complication rate. Recommendation Due to high complication rate AO tubular EF should be used only temporarily in case there is high level of contamination, severe soft tissue or bone damage with or without compartment syndrome and high fracture grades such as grade III fractures. This is for wound care as well as fracture stabilization since internal fixation cannot be used primarily in that condition