Surgical Versus Non-Surgical Treatment of Humeral Shaft Fractures Compared By a Patient Reported Outcome: The Scandinavian Humeral Diaphyseal Fracture Trial (SHAFT) - A Study Protocol For a Pragmatic Randomized Clinical Trial

Background: The outcome of non-surgical treatment is generally good, but the treatment course can be long and painful with approximately a quarter of the patients acquiring a nonunion. Both surgical and non-surgical treatment can have disabling consequences such as nerve injury, infection and nonunion. The purpose of the study is to compare patient reported outcome after surgical and non-surgical treatment for humeral shaft fractures. Methods: A pragmatic randomized controlled trial is planned with two study groups (SHAFT-Y and SHAFT-E). A total of 287 eligible acute humeral shaft fractures are scheduled to be recruited and randomly allocated to surgical or non-surgical treatment with the option of early crossover due to delayed union. The surgical method within the allocation is decided by the surgeon. The primary outcome is the Disability of Arm, Shoulder and Hand (DASH) score at 52 weeks, and is assessor blinded. The secondary outcomes are DASH score, EQ-5D-5L, pain assessed by visual analogue score, Constant-Murley score including elbow range of motion and anchor-questions collected at all timepoints throughout the trial. All complications will be reported including; infection, nerve or vascular injury, surgical revisions (implant malpositioning, hardware failure, aseptic loosening and peri-implant fracture), major adverse cardiovascular events, and mortality. Patients declining randomization will be asked to enroll into an observational cohort with same outcomes and post-treatment regimes. Discussion: SHAFT will provide information on the effectiveness of two standard treatments for humeral shaft fractures, while taking the dilemmas within the population into account. Trial registration: Clinicaltrials.gov, NCT04574336. Registered on 5 October 2020.