The N-brace trial: Does arm position during immobilisation of proximal humerus fractures influence outcome - A preliminary study

Traditional initial management of proximal humerus fractures (PHF) involves arm immobilisation in a simple sling (SS) in an internally rotated position. We believe this risks fracture displacement and imbalance of soft tissues, encouraging malunion and stiffness. A neutral-rotation brace (NRB) maintains an arm position which may prevent this, leading to quicker and superior recovery. We randomised patients with two- to four-part PHF into 4 weeks of immobilisation with either a SS or NRB, independent of surgery. Range of motion (ROM), subjective shoulder value (SSV), DASH, Constant–Murley (CMS) and Oxford Shoulder (OSS) scores were assessed at 6-weeks, 3-months and 1-year post-injury. The SS group included 11 patients vs 9 in the NRB group. At final follow-up, the SS and NRB groups had mean DASH scores of 42 vs 35, OSS 42 vs 46, CMS 71 vs 86, SSV 84% vs 92%, respectively. ROM was superior with the NRB (elevation 159°, ER 47° and IR score 8 vs 140°, 37° and 7 with SS). Despite being a small series, our results demonstrate a trend towards NRB providing better outcomes. This feasibility study supports the need for a larger multi-centre randomised controlled trial comparing these immobilisation methods for PHF.