Treatment of Shoulder Instability & Dislocation
What is it?
A shoulder dislocation is one of the most traumatic injuries a shoulder can undergo. Many shoulders will continue to dislocate or be symptomatic if the damage is not repaired. Shoulder instability surgery is aimed to repair the damaged labrum, ligaments, and bone associated with a dislocation or other traumatic even so that function to the shoulder can be restored. Most instability surgeries can be performed arthroscopically where the torn labrum and ligaments are reattached to the edge of the socket with suture. Some patients may require an open incision, particularly those that have failed a prior attempted repair or have bone loss from their socket.
Open versus Arthroscopic Repair
The decision to have an open versus arthroscopic instability repair is dependent on several different variables. For the majority of patients with unstable shoulders, an arthroscopic repair is ideal since it allows for a more rapid early recover, better visualization of the entire joint, and ability to address anterior and posterior joint problems as the same time without additional incisions. The joint is visualized with a small camera and the surgery is performed through small incisions around the joint (each about 1 cm). It is an outpatient surgery and is minimally invasive.
In some patients however, their should instability may be better treated with an open incision. Below are some factors that may lead a surgeon to recommend an open repair instead of arthroscopic.
- Significant bone loss from the socket (glenoid)
- Significant bone loss from the ball (humeral head)
- Revision instability surgery
What are the risks?
The surgery it self is generally very safe whether is done arthroscopically or open. There is very little blood loss, very low risk of infection, and very low risk of neurovascular injury. There are the general risks of anesthesia which is very low in most healthy patients. Usually just a light anesthetic is used because most patients elect to have their arms numbed with a nerve block during the surgery. The risks specific to the surgery itself include the following:
Recurrent Instability: While the risk of recurrent instability is much less than if surgery was not performed, there is still a chance that a shoulder can dislocate again following surgery. This is particularly a risk in younger patients who perform impact sports.
Shoulder Stiffness: Some stiffness in the shoulder following instability is not necessarily a bad thing since the goal of the procedure is to keep the shoulder stable. Most stiffness can be improved with continued therapy
Post-traumatic arthritis: Some shoulders can develop arthritis after instability surgery. Usually this take decades to develop. It is not certain whether this is caused by initial trauma from the dislocation or from a side effect of tightening the shoulder with surgery, but both can certainly contribute to this long term complication.
What is fixed in instability surgery
The labrum: If you have dislocated your shoulder, there is a very high chance that you have torn your labrum. The labrum is a thick fibrous tissue that deepens the effective depth of your socket making your shoulder more stable. It also serves as the attachment site for the ligaments around your shoulder. Unfortunately, the labrum has a very limited ability to heal itself. Therefore, many patients who need optimal function out of their shoulder will require surgical repair.
The capsule/ligaments: Sometimes the capsule and ligaments can be stretched from a dislocation, and other times patients are born with looser capsules than others making them more prone to dislocations. If this is the case, the capsule/ligaments may need to be tightened by sewing together overlaping folds of the tissue, much like pleating fabric together.
The bone: Some patients with traumatic dislocations or recurrent dislocations may develop bone loss in the socket (glenoid). In acute dislocations, this bone can be fractured off and often times it can be sewn back into place. In patients who have dislocated many times, this bone loss can develop from the repeated shoulder trauma. In these instances, new bone has to be taken from another part of the body or from a cadaver to recreate a deeper socket.
Bone loss can also occur from the ball of the shoulder (humeral head). This is known as a Hill-Sachs lesion. These occur because when the shoulder dislocates, the back side of the ball can impact against the edge of the socket causing a dent in the ball. Some Hill-Sachs lesions may need to be filled with tissue or bone graft to prevent further dislocations since the edge of the socket can fall into the defect causing the shoulder to dislocate.
What are the expected results?
Most patients are able to return to full, pain free use of their shoulder after they are fully recovered from surgery and have rehabed their shoulder effectively. The majority of patients lose their feeling of "apprehension" or the sensation that the shoulder is going to pop out of place. Many patients are also able to return to high levels of athletic activity depending on their handedness and specific demands of their sport. Most patients will not dislocated their shoulder again, but the specific risk is different from patient to patient depending on the activities they like to perform.
What is the recovery like?
The surgery is generally performed as an outpatient meaning you will go home the same day as the surgery. Patients will remain in the sling for a minimum of 4-6 weeks with restrictions on the use of your arm. After this period of time, patients will work with a therapist to gradually improve the range of motion in their shoulder and improve their strength. Functional strengthening of the shoulder typically begins about 3 months after surgery with full recovery taking about 6 months or more.