Shoulder Instability and Chronic Dislocation

The shoulder is a special joint as it is really a combination of several joints—combined in such a way by an intricate arrangement of muscles and tendons—that provides the arm a wide range of motion, flexibility and stability. The rotator cuff is a group of four shoulder muscles that surround the top of the upper arm bone, (the humerus), and holds it in the shoulder joint. These muscles are responsible for moving the arm in various directions, and unlike the massive deltoid muscle of the upper arm, are smaller and generally more vulnerable to injury. The four muscles and tendons of the rotator cuff are the supraspinatus, infraspinatus, teres minor, and subscapularis. It is the supraspinatus that is most commonly inflamed or torn.

The supraspinatus, and the rest of the shoulder, because it is built and expected to allow a remarkable array of motion, frequently is subjected to the injuries listed below, causing problems of instability or impingement of soft tissue and pain. The pain may be constant, or may occur only when the shoulder is moved. In any case, severe shoulder pain that persists more than a few days should be diagnosed and treated as necessary.

Chronic Shoulder Instability Syndrome

Chronic shoulder instability syndrome results from a loosening of the connective tissue caused by trauma such as dislocations, subluxations (partial dislocations of the shoulder), and from less detectable micro-traumas caused by repetitive strain, or from congenitally loose shoulder joints. Recurrent pain or tenderness in the shoulder joint and weakness in the arm are two of the more common symptoms, but severe examples include patients whose shoulders pop in and out of joint. Frequent shoulder dislocations stretch the brachial plexus, the nerves that run from the neck down the arm. This process can cause permanent nerve damage, pain, and loss of use of the arm.

For those individuals who suffer from chronic shoulder instability, dislocations may occur frequently. This occurs because first dislocations usually require a significant amount of force as in anterior dislocations, in which the anterior static shoulder stabilizers are stretched or torn away from the bone. Approximately 95% of shoulder dislocations are this type and typically occur when a person falls on their outstretched hand, or sustains a downward motion blow to the shoulder.

Until recently it was common in cases of dislocation to immobilize the shoulder for long periods of time. But studies showed that while immobilization helped alleviate the pain of such injuries, it also contributed to a general weakening of the ligaments and predominance of adhesive capsulitis.

The shoulder is held together by soft tissue stabilizers, the ligaments that connect bone to bone. Over the course of time, especially in sports that involve heavy shoulder-to-shoulder contact (such as hockey, lacrosse, football, wrestling, and basketball), the ligaments may stretch out and become “lax.” When the ligaments become lax, the risk of dislocation and separation becomes greater.

Within the shoulder are its three main joints. Most dislocations or subluxations occur in the glenohumeral joint, the ball and socket joint. Lesser or more rare dislocations occur at the acromioclavicular or AC joint and sternoclavicular joint, the SC joint.

In a study published in the British Journal of Sports Medicine, (1) researchers took a look at rugby players with measurable shoulder laxity to gauge the risk of shoulder dislocation. What they found was that 50% of the athletes tested were at significant risk.

It is estimated that 95% of shoulder dislocations occur when athletes suffer a blow to the shoulder that forces the shoulder joint “back” or downward, or occur when they fall to the ground with their arms stretched over their heads.


Chronic Shoulder Dislocation Treatment

Traumatic shoulder dislocation is a frequent injury in the sports population. An acute shoulder dislocation often means a one-time traumatic episode, whereas chronic shoulder instability indicates multiple recurrent dislocations.

Following an initial shoulder dislocation, doctors debate whether or not to perform surgery to prevent recurrence. If there is an accompanying labral or tendon tear, that can be addressed along with tightening of the capsule around the joint. This can lead to a loss of range of motion. I have used Stem Cell Therapy with platelets (both are in the bone marrow) or just PRP from the blood, both with good results, to tighten the shoulder after a failed surgery for chronic dislocations.

If the patient is under 30 years of age, shoulder surgery is typically recommended by surgeons because younger athletes are much more prone to repeated dislocations than older athletes. Until recently, it was common in cases of dislocation to immobilize the shoulder for long periods of time. But studies showed that while immobilization helped alleviate the pain of such injuries, it also contributed to a general weakening of the ligaments and predominance of “adhesive capsulitis,” where the arm is frozen (frozen shoulder) and can no longer be lifted.

Surgery for shoulder dislocation can be effective for some but, as always, surgery should be considered a last option because of issues of complications, downtime (immobilization), and—for both the “weekend warrior” and the professional athlete—a weakening of the shoulder through the removal of or damage to other connective tissue in the surgical process.

Some athletes may opt for immediate surgery because of the typical six-month healing time (if healing occurs at all) required in the case of a Bankart lesion (an injury of the anterior [inferior] glenoid labrum) without Stem Cell Therapy or PRP. Researchers have pointed out that “[r]epairs of degenerate and torn tissue are often prone to failure due to many intrinsic and extrinsic factors” and that Platelet-Rich Plasma Therapy has been shown to reduce pain and improve recovery in shoulder tears.(2)

The key to avoiding shoulder surgery or shoulder separation requiring surgery is to strengthen the shoulder girdle. This can be accomplished by working the strong shoulder muscle group and by treating the weakened shoulder ligaments with injections of regenerative medicine.

To understand the importance of having strong ligaments to hold the shoulder together, the patient needs to understand that the severity of the shoulder dislocation is measured by the degree of injury to the ligaments and the amount of instability of the joint.

Shoulder Separation

The acromioclavicular (AC) and the coracoclavicular (CC) ligaments hold the shoulder together at the point where the collarbone (clavicle) and the top (acromion) of the shoulder meet. This joint can also be traumatically separated. I see this most commonly in bicycling accidents in which the patient has flown over the handlebars and landed on the shoulder.

This is a very small joint that heals well with regenerative medicine.

  • In type I level separation, the AC is partially torn; the CC is not.
  • In type II separation, the AC is completely torn; the CC is partially or not torn.
  • In type III separation, both ligaments are completely torn.

With this injury one can often see the collarbone sticking up above the top of the shoulder. Obviously, the more significant the tearing, the longer the athlete is out of their sport. Untreated shoulder instability can lead to an alteration of an athlete’s game to protect the sore shoulder, or, worse, chronic shoulder separation that can keep athletes away from their sport for significant amounts of time.

Bone Marrow aspirated stem cells injected into the shoulder

The concept behind both stem cell therapy and platelet rich plasma therapy in treating chronic shoulder dislocation or subluxation is that the treatments will repair and strengthen the soft tissue within the should capsule to restore and maintain shoulder stability.

This is pointed out in our research which appears in the peer-reviewed journal Cogent Medicine. The study can be found here in its entirety: Treatment of shoulder osteoarthritis and rotator cuff tears with bone marrow concentrate and whole bone marrow injections with a June 20, 2019 publication date.


1 Cheng SC, Sivardeen ZK, Wallace WA, Buchanan D, Hulse D, Fairbairn KJ, Kemp SP, Brooks JH. Shoulder instability in professional rugby players—the significance of shoulder laxity. Clinical Journal of Sport Medicine. 2012 Sep 1;22(5):397-402.
2 Mei-Dan O, Carmont MR. The role of platelet-rich plasma in rotator cuff repair. Sports Med Arthrosc. 2011 Sep;19(3):244-50.


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