Shoulder dislocations may be complicated by fractures of the bones that make up the shoulder joint. Up to 25% of patients will have an associated fracture. Not included in these numbers are the Hill-Sachs deformity that may occur in up to 75% of anterior shoulder dislocations.
Nerve damage is always a potential complication. Commonly the circumflex axillary nerve may be injured which shows as numbness in small patch distribution on the outside of the upper arm. From time to time I consult with clients suffering this symptom without even having dislocated the shoulder. In this case it is more than likely they have partially subluxed the joint. This nerve often recovers spontaneously in a few weeks.
Rotator cuff injuries are commonly seen in older patients who dislocate their shoulder. The diagnosis may be difficult to make initially and often is made in follow-up visits with the health-care provider.
But the big one is that one I mentioned at the start, its a rare complication of shoulder dislocation. Tearing of the axillary artery, the main artery that supplies blood to the arm and brachial plexus injury, in which the nerve bundle that attaches the arm nerves to the spinal cord is damaged. Both these structures are located in the axilla (your armpit) and are potentially damaged by the initial dislocation or by attempts to reduce the dislocation (never let anyone attempt this using force).
Why have I brought this injury up? This time its not me, a rider I used to ride bike trials with has suffered this horrible injury. Its never nice to see a fellow rider facing down the barrel of a long lay off. What would I do in the same circumstances? From my perspective, which is many years of helping rehab those that have suffered such injury. Diet is key to allowing full recovery. I would be supplementing with Great Lakes Gelatin to ensure the shoulder ligaments come back stronger than ever, testing my pH to allow full recovery via dietary adjustment to keep the pH in range, using vitamin E to keep the blood from becoming to viscose through immobility, and supplementing with vitamin B6 & B12 to help the nerve recovery. In short I would remove all the junk out of my diet and eat like a god.