Shoulder Dislocation / Instability

​Shoulder dislocations make up 50 percent of all major joint dislocations. The shoulder joint is the body's most mobile joint and can move in many directions. This flexibility is due to the design of the shoulder, which has no inherent stability. Unlike the hip joint, which has a very deep, very stable bony socket surrounding and supporting the ball of the hip, the shoulder has a shallow socket (glenoid) which does not provide support for the ball of the shoulder (humeral head). The shoulder must rely purely on soft tissue structures (surrounding ligaments and muscles) to maintain stability. These soft tissues allow the shoulder joint to have great flexibility but, unfortunately, they also make the shoulder an easy joint to dislocate.

Patients who have sustained a shoulder dislocation (or multiple dislocations) are said to have “shoulder instability.”

Normal Shoulder Anatomy

The shoulder joint can dislocate partially or completely and can dislocate in different directions.

Partial Shoulder Dislocation. In a partial shoulder dislocation (subluxation), the humeral head partially and painfully shifts out of the socket (glenoid) and then typically pops back in place.

Complete Shoulder Dislocation. In a complete shoulder dislocation, the humeral head dislocates all the way out of the socket and typically remains dislocated until it is manually manipulated back in place, which is typically performed by an ER doctor.

Direction of Dislocation.

• An anterior shoulder dislocation is the most common type of shoulder dislocation, occurring when the humeral head slips forward and down out of the socket. This commonly occurs when the shoulder is injured in a throwing position.

Anterior Shoulder Dislocation

• A posterior shoulder dislocation is less common than an anterior dislocation and occurs with trauma as well as with injuries sustained due to electric shock and during seizures.
• Inferior shoulder dislocations are very rare (only 0.5% of all shoulder dislocations) and typically occur as the result of a high-energy injury.

Typical symptoms of a dislocated shoulder include:

• Extreme Pain
• Unusual appearance of the shoulder compared to the uninjured side
• Swelling
• Weakness
• Bruising
• Numbness

In complicated cases, a shoulder dislocation may tear ligaments or tendons in the shoulder or damage nerves.

Shoulder dislocations can occur due to:

• Trauma from a car accident or a fall
• A strong blow to the shoulder
• Extreme rotation (this can pop the shoulder out of place)
• Contact sport injuries

Normal Shoulder X-Ray (Left) and X-Ray Showing Dislocated Shoulder (Right)

If the shoulder has completely dislocated, then an urgent visit to the emergency room is nearly always required to treat the dislocation. A dislocated shoulder is a medical emergency and if the shoulder remains dislocated after the injury, then a trip to the ER should be made urgently. The ER doctor will manipulate the ball of the upper arm bone (proximal humerus) back into the joint socket. This process is called a closed reduction and is performed under sedation. Severe pain stops almost immediately once the shoulder joint is relocated back in place.

Sometimes a first-time shoulder dislocation can be successfully treated with nonoperative management but surgery may be indicated depending upon your age and activity level.

Dr. Jurek will examine you in her office within the first few weeks following a shoulder dislocation and will determine whether additional advanced imaging (usually an MRI with dye injected into the shoulder) is needed and if nonoperative management is the best treatment route going forward.
​
(See “Surgery” below for more information on surgical treatment of shoulder dislocations.

If nonoperative treatment is chosen, Dr. Jurek may immobilize your shoulder in a sling for a couple of weeks. Rest and cold therapy will help to reduce the pain and swelling.

Physical therapy will be initiated once the pain and swelling improve. This will help restore your shoulder's range of motion and strengthen your muscles. Rehabilitation may also help prevent dislocation of the shoulder again.

If your shoulder continues to dislocate or subluxate despite physical therapy or if the MRI shows injury to certain shoulder structures, surgery may be necessary to repair or tighten the torn or stretched ligaments that help stabilize the shoulder.

An MRI with dye injected within the shoulder joint helps to localize the injured structure(s) and allows Dr. Jurek to plan the appropriate surgery.

The repair usually involves inserting a special implant called a “suture anchor” into the bone of the socket (glenoid). Dr. Jurek then threads the attached suture around the injured area of fibrocartilage (called the “labrum,” which is a structure that deepens the socket of the shoulder and allows the shoulder to be stable). She then ties the sutures to cinch the torn labrum back to its anatomic location against the glenoid of the shoulder.

Postoperatively, the shoulder will be immobilized in a sling for four to six weeks to allow healing of the repair. Physical therapy is started after the initial period of immobilization and usually continues for about three to five months. A return to sports depends on the particular sport but usually is allowed at about six to eight months after shoulder stabilization surgery.

This is an intraoperative photo of arthroscopic shoulder stabilization surgery. The green threads are sutures attached to anchors in the bone and are wrapped around the injured labrum, tightened, and tied, securing it back where it belongs against the bone to make the shoulder stable.

If you would like to schedule a consultation with Dr. Jurek for evaluation and treatment of your shoulder instability, please call (206) 386-2600. You may also request an appointment online.