Generally surgery is not required in such cases, its good to use ice packs for initial 2-3 days and apply some pain killer gel with rest. but if he is able do overhead movements of his shoulder, chances of fracture and dislocations are not there or rare.
Next Steps
go to a physiotherapist and take the treatment. Ultrasonic therapy helps in healing of muscle stretched or inflamed,heat therapy increases blood circulation and TENS helps in relieving pain,Exercises will increase the muscle strength.Do it for at least 2-3 weeks.You will get the relief for sure.......In chronic cases ,if not responding(no relief at all) after taking physiotherapy,need to go to an orthopedecian.
Health Tips
No weight lifting, no cold exposure,dont overstretch and delay to go to a physio....take care.