IntraMedullary nailing Versus EXternal ring fixation for the treatment of tibial shaft fractures (IMVEX): a multicentre randomized controlled clinical trial

Abstract

Aim One of the most common patient-reported complaints following intramedullary nailing (IMN) of tibial shaft fractures is anterior knee pain reported by 10% to 80% of patients. The present study aimed to compare the 12-month Knee injury and Osteoarthritis Outcome Score (KOOS) sport and recreation activities subscale (sport/rec) scores after IMN with external ring fixation (RF) to adult patients with tibial shaft fractures. Methods This study was a pragmatic multicentre randomized, non-blinded trial, with two-group parallel design. Included were adult patients (aged ≥ 18 years) presenting with an acute tibial shaft fracture deemed operable with an intramedullary nail. The primary outcome was the KOOS sport/rec, ranging from 0 (worst score) to 100 (best score) at 12-month follow-up. Secondary outcomes included the Foot and Ankle Outcome Score (FAOS), health-related quality of life assessed by EuroQol five-dimension five-level health questionnaire, and pain scores. Results A total of 67 patients were included in the study. In all, 33 patients were randomized to standard IMN and 34 patients to RF. The mean age of the patients was 47.7 years (SD 19.2; 18 to 84) and 34% were female (n = 23). The primary analysis revealed no statistically significant difference in KOOS sport/rec between the IMN and RF groups at the 12-month follow-up (adjusted mean difference -18.1 (95 % CI -43.4 to 7.2); favouring RF). Conclusion No statistically significant differences in the KOOS sport/rec were observed between RF and IMN at 12-month follow-up. However, these results should be interpreted with caution, due to high risk of a type II error.