Sublaxed shoulder new grad

I have a patient who is IDD and has a sublaxed shoulder. He is about a year out from sx after his car accident. What should I be evaluating with him? What are some interventions you recommend? He has a splint that allows him to swing his arm for walking but I don’t think it supports his shoulder very well. Are there any attachments or different recommendations you recommend that could allow him to still use his arm while walking? I have measured PROM for shoulder flexion and abduction. I have also measured grip strength. Any advice is greatly appreciated.