634 MEP138 – The developed elastomeric shoulder brace normalizes tackling posture in recurrent shoulder dislocation rugby players

AbstractBackground Shoulder dislocations due to tackles and so on are very common among collision sports athletes such as rugby. One of the causes of shoulder dislocations is bad tackling posture. Therefore, we developed an elastomeric brace, that controls anterior and horizontal extension, and external rotation to eliminate the fears of reinjury. We found out that the anterior movement was controlled with the brace just like the normal side by measuring the maximum external rotation at 140–150°abduction by MRI (Inoue, 2019). Our brace prevented 80% of re-dislocation, whereas another reported brace prevented 59% (Inoue, 2021).Objective To verify the effects of the developed elastomeric brace to prevent re-dislocation in collision athletes on tackle movements.Design Quasi-experimental studySetting/Patients Five male rugby players before surgery for recurrent shoulder dislocationsInterventions The brace with no metal, was made of Thermoplastic Styrene Elastomer, which is a material that is self-adhesive, highly elastic (elongation rate: 500–1500%), and flexible. Main Outcome Measurements The high-speed video was taken of the tackling posture on the dislocated side with and without bracing, and the normal side. Two-dimensional motion analysis was performed. We assessed anxiety of dislocation by the Visual Analog Scale.Results Comparison of the dislocated side (without/with bracing): kyphosis angles were 44.6±4 degrees/35.8±5 degrees, displacements of the center of gravity were 78.8±5 cm/72.9±3 cm, anteversion angles of legs were 6.2±20 degrees/26.1±17 degrees, contact distances were 15.9±2 cm/12.8±2 cm, trunk lateral flexion angles were -9.2±7 degrees/8.2±6 degrees, and VAS scores were 58±13 mm/14±9 mm. All except contact distances improved significantly (p < 0.05), and there was no difference in tackle posture with bracing compared with the normal side.Conclusion With bracing, the tackling posture on the dislocated side normalized. The stability of the developed brace showed a strong psychogenic effect by reducing anxiety of dislocation.