Problem
Traumatic primary anterior shoulder dislocation is common among young active individuals, with recurrence rates of 30–40% within one year after a first dislocation. Recurrent instability leads to progressive capsulolabral injury, reduced shoulder function, diminished participation in work and sport, and increases the likelihood of requiring surgery. Although post-reduction immobilisation is recommended in guidelines, current practice varies considerably. Recent UK guidelines emphasised a major evidence gap: whether no immobilisation affects the risk of recurrent dislocation compared with standard immobilisation periods.
Aim
To determine whether no prescribed immobilisation is non-inferior to 3-week prescribed immobilisation in short term function and recurrent dislocation over 12 months.
Population
Adults aged above 18 years presenting with a first‑time traumatic anterior shoulder dislocation confirmed clinically and/or radiographically, managed non‑operatively in the emergency department.
Outcomes
Primary outcome is short term shoulder function measured via Western Ontario Shoulder Instability Index Short Form (WOSI-SF) at 6 weeks post injury. Secondary outcomes include the proportion of participants experiencing recurrent shoulder dislocation and surgical stabilisation within 12 months; short-term shoulder pain at 1-,2-, 3-days, 1- and 3- weeks; WOSI-SF at 3-,6- and 12-months; return to work and sport and complications measured at 6 weeks, 3- , 6- months and 12-months. We will also record broader healthcare utilisation, adherence to the allocated intervention, and associated costs over the 12-month follow-up period.
Methods
This is a pragmatic, point-of-care randomised non-inferiority trial with two parallel arms. Participants will be randomised 1:1 using a secure, concealed web-based system stratified by site and age. A waiver of consent for randomisation will be sought since both trial arms reflect accepted standards of care in Australia. Based on a 39% recurrence rate, a non-inferiority margin of 10 percentage points, 80% power, and a one-sided α of 0.05, 20% participant loss, we require 260 participants per arm (520 total) with complete 12-month data.