Shoulder Instability Specialist

Sports Medicine Physician

Are you an athlete who participates in a sport that involves a repetitive overhead motion? If so, you may be at risk of developing shoulder instability. Shoulder instability may occur from a shoulder dislocation or repetitive strain placed on the ligaments. Shoulder instability specialist, Dr. Mark Getelman provides diagnosis and both surgical and nonsurgical treatment options for patients in Los Angeles who have developed shoulder instability. Contact Dr. Getelman’s team today!

What to Know About Shoulder Instability and Possible Glenoid Bone Loss

The shoulder is considered the most mobile joint in the human body. Composed of the humerus (upper arm bone), scapula (shoulder blade) and clavicle (collarbone), the shoulder joint allows patients the ability to lift and rotate the arm, as well as to reach overhead. With this great range of motion we are at risk to develop shoulder instability particularly with sports and repetitive overhead activity. Instability of the shoulder joint occurs when the humerus head is forced out of the glenoid (socket). Certain patients may experience chronic shoulder instability that leads to significant glenoid bone loss. Dr. Mark Getelman, orthopedic shoulder specialist in the Van Nuys, Westlake Village, Thousand Oaks and Los Angeles, California area, is an expert in diagnosing and treating shoulder instability particularly the most complex injuries associated with glenoid bone loss.

Shoulder instability may occur from a traumatic shoulder dislocation or repetitive strain placed on the ligaments that causes them to become loose in one direction or multiple directions. Multidirectional instability often occurs in patients with no history of traumatic shoulder injury. Patients affected by this form of instability may experience shoulder hypermobility in multiple directions. Some of these patients may be diagnosed as “double jointed.”

Ongoing shoulder instability is disabling and can become associated with bone loss in certain patients. Once bone loss is diagnosed by Dr. Getelman, many patients are required to undergo more comprehensive surgery to address the issue.

Shoulder Instability Symptoms

Common symptoms of shoulder instability include pain and recurring episodes of the shoulder joint “giving out” and a sensation of the joint feeling loose.

Shoulder Instability Diagnosis

Dr. Getelman will perform a thorough medical review and physical examination to assess degree of shoulder instability and general ligament looseness. X-rays and an MRI or CT scan will also be performed in the majority of cases. The x-rays will help Dr. Getelman determine the extent of glenoid bone loss, while the MRI will display any additional damage to the surrounding soft tissues.

Are you experiencing shoulder instability or glenoid bone loss?

Schedule an office consultation with Dr. Getelman today.

Shoulder Instability Treatment


Dr. Getelman commonly attempts to address multidirectional and some unidirectional shoulder instability without bone loss with conservative measures. Non-operative measures include anti-inflammatory medications (NSAIDs), activity modification and a physical therapy program to strengthen the muscles that surround the shoulder to provide dynamic stabilization of the joint.


If glenoid bone loss is determined, Dr. Getelman typically recommends surgical stabilization and may offer an arthroscopic glenoid augmentation. Dr. Getelman will utilize bone graft to rebuild bone loss and reconstruct the glenoid during this procedure. Graft options include a distal clavicle autograft, iliac crest autograft and distal tibia allograft. In autograft cases, a patient’s own tissue is harvested, either from the clavicle or the iliac crest (largest bone in the hip), and used to reconstruct the area of glenoid bone loss. In distal tibia allograft cases, a portion of a donor’s tibia is harvested and used to perform the reconstruction. Dr. Getelman will explain the appropriate graft option in great detail with each patient at the consultation.

Shoulder Dislocation FAQ

1. What is the difference between shoulder dislocation and shoulder separation?

The injuries are quite distinct. In the case of a dislocated shoulder, after a fall, a sports injury or hard blow to the shoulder, the top of the arm bone pops out of the shoulder socket. A separated shoulder, on the other hand, happens when a fall or a hard strike causes a tear to one of the ligaments connecting the collarbone to the shoulder blade. Because the collarbone is no longer securely in place, the collarbone might also move out of position and press against the skin near the top of the shoulder.

2. What is the difference between shoulder subluxation and shoulder dislocation?

A subluxation is a partial dislocation of the shoulder joint and is attributed to shoulder instability. It can occur in one or multiple directions. If it’s in one direction, it is most frequently to the front or anterior, often referred to as anterior instability, which is when the arm or humerus bone pops out the front of the joint, anterior to the glenoid socket. This condition has various causes: accident or traumatic injury or repetitive use.

3. How can I fix my shoulder if it keeps popping of the socket?

The first step is to see your doctor, who may have your shoulder X-rayed. It’s possible that you dislocated your shoulder the first time and it damaged the surrounding soft tissues (labrum,ligaments and capsule), which can lead to further dislocations. In cases of frequent shoulder dislocations, Dr. Mark Getelman, an orthopedic surgeon who practices in Van Nuys, Thousand Oaks and covers surrounding Los Angeles, California communities, may recommend dislocated shoulder surgery, which aims to repair  the labrum and ligaments and joint surface damage, and reduce the risk of re-dislocations and arthritis. Dr. Getelman has also developed an innovative shoulder technique called the “Hospital-Corner” repair.

4. What causes the shoulder to pop in and out?

The shoulder is the body’s most moveable joint, helping lift and rotate the arm and reach over the head. Once the shoulder has been dislocated, it’s susceptible to repeat episodes. Those repetitive episodes are known as recurrent or chronic shoulder instability.

5. Why does my shoulder dislocate easily?

If the labrum, ligaments and capsule around the shoulder are torn or become loose, dislocations can happen repeatedly. There are three ways that the shoulder can become unstable — a dislocation from a trauma or severe injury, repetitive strain (some individuals have looser ligaments in their shoulders, the result of repetitive motion) or multidirectional instability (these individuals simply have naturally loose ligaments and can develop symptoms of instability without specific trauma).

6. What is a partially dislocated shoulder?

In this situation, the rounded top of the long bone in the arm that runs from shoulder to elbow (the humerus) slides partially out of the shoulder socket, as opposed to completely out of the shoulder socket.

7. What shoulder dislocation is most common?

The most common injury results in an anterior or forward dislocation, usually the result of falling on the shoulder itself or an outstretched hand. The ball or humeral head slides out in front of the glenoid socket.

8. What causes shoulder dislocation?

An acute trauma or fall onto an outstretched arm or repetitive activity that pulls the shoulder backward or rotating it too far can cause the humerus (the ball of the upper arm bone) to pop out of the socket (otherwise known as the glenoid). If you’re an athlete who plays sports that involve a lot of overhead motion — such as volleyball, baseball, swimming and tennis — or your profession requires you to lift objects over your head (a professional house painter, for example), you are at risk, because over time, the repetitive motion over the head can weaken and stretch the shoulder capsule and ligaments. Another factor is genetics. If you naturally have loose ligaments in the shoulder area, you may not have the support to keep the ball of your shoulder in its socket. Therein lies the risk of shoulder instability.

9. What is shoulder dislocation reduction?

Several kinds of reduction techniques can be used to reduce anterior shoulder dislocation — in other words, to put the shoulder back into the socket. Since there are risks inherent to shoulder dislocation, the very safest route is to see an experienced medical provider who can perform the reduction procedure while the patient is under sedation. The goal is to manipulate the bones so that they will slide back into the correct position.

10. What does shoulder dislocation feel like?

The most common symptoms are pain in the upper arm and shoulder (which gets worse during attempts to move it), decreased motion, swelling, numbness and weakness, bruising and deformity of the shoulder (the result of a forward dislocation).

11. How do I tell of the shoulder is dislocated?

First and foremost, there is often immediate and intense pain. Also look for swelling or bruising, the lack of mobility in the joint and a shoulder that is visibly deformed or out of joint. You may experience muscle spasms, numbness and tingling.

12. What is anterior shoulder dislocation?

Accounting for upwards of 95 percent of shoulder locations, anterior dislocation occurs when the humeral head — which forms the ball of the ball-and socket shoulder joint — is displaced anteriorly (toward the front of the body).

13. What is recurrent shoulder dislocation?

Each time a shoulder dislocation occurs, more damage occurs (the ligaments are stretched and torn). Over time, if this happens repeatedly, it causes damage that can lead to bone loss of the ball and socket making the instability even more likely. Over time, instability can eventually lead to arthritis. If rest, immobilizing the arm in a sling and physical therapy (after the pain and swelling go down) do no correct the problem, and the shoulder instability continues, surgery is a viable option. In that case, the object is to repair or tighten torn ligaments, helping to keep the joints in place.

14. Where does a dislocated shoulder hurt?

The pain is sudden and severe, generates in the shoulder and upper arm, and it will hurt to move the arm or turn it outward. It’s possible to dislocate the shoulder in several directions, the most common being the anterior position. In that situation, the humeral head is moved to the front of the joint. A posterior dislocation happens when the humeral head moves backward toward the shoulder blade. Muscle spasms may also occur in the arm and shoulder, which make it more painful.

15. Where does a shoulder dislocation occur?

It can dislocate partially or completely, in a forward, backward or downward direction. A doctor will confirm the diagnosis based on the symptoms and the results of an X-ray. The three main types of shoulder dislocation are anterior (which is the most common), posterior and inferior. Most often, an anterior dislocation is caused by a blow to the arm or a fall on an outstretched arm. A visible sign is the way the person holds his or her arm — in an externally rotated and abducted direction (i.e., away from the body).

16. What are the types of shoulder dislocation?

There are three:

  • Forward (anterior) accounts for some 95 percent of shoulder dislocations. In such an injury, the humeral head separates from the glenoid socket, as a result of throwing a ball overhead, spiking a volleyball or falling on an outstretched arm.
  • Backward (or posterior) is a less common dislocation where the upper part of the humerus is displaced toward to the back of the body. They can happen, like anterior dislocations, from a fall or blow to the arm, and can also be the result of repetitive stress or a strength imbalance in the rotator cuff muscles.
  • Downward (inferior) dislocations are the most rare and result from a hyper abduction that forces the humerus head against the acromion (the highest point of the shoulder). In this scenario, complications such as a fracture or soft tissue injury is also present.

17. What is multidirectional instability (MDI) of the shoulder?

It’s a looseness of the joint either from joint weakness or increased mobility. The most common cause is shoulder overuse, particularly in individuals who engage in repeated overhead arm movements such as swimmers and baseball pitchers. The joint may slip out of the socket in a forward, backward or downward direction.

18. What are the symptoms of shoulder instability?

Chronic instability can lead to recurrent subluxations, which is when the shoulder slips but does not dislocate or come completely out of the socket. The shoulder might feel “loose.” This can happen simply by raising a hand above the head. The shoulder can become so loose that it subluxates frequently. With complete dislocations, there can be stretch injuries to the nerves as well. In situations where the nerves have been stretched, the patient may develop numbness on the outside of the arm, just below the top of the shoulder. Some of the shoulder muscles may be temporarily weak.

19. What is anterior instability of the shoulder?

This injury to the glenohumeral joint (GHJ) — where the humerus is displaced from its normal position and the joint surfaces no longer touch each other — can occur when the shoulder is in a vulnerable sports-related position, such as throwing a ball. It also happens when an individual falls on an outstretched hand, with the shoulder rotating away from the body.

20. What is glenohumeral instability of the shoulder?

The cause of shoulder pain and disability in active individuals, glenohumeral instability is the inability to keep the humeral head centered in the glenoid fossa (which is the cavity that forms the glenohumeral joint along with the humerus).