Shoulder Instability and labral tears
Overview
The Shoulder has the greatest range of motion of any joint in the human body. Because of this, it is commonly dislocated. The shoulder is a ball-and-socket joint made up of the humeral head (ball) and glenoid (socket). Since the glenoid is very shallow, the stability of the shoulder relies on various soft tissue restraints. The glenohumeral ligaments, which are thickenings of the shoulder capsule along with the labrum, which is a soft bumper that extends from the bony socket, give the shoulder stability. There is also dynamic stability imparted by the many muscles that cross the shoulder joint (including the rotator cuff), and when activated, compress the humeral head into the glenoid. Both the bone and soft tissues can be damaged from both overuse and trauma.
Causes
Shoulder instability usually arises after a dislocation of the humerus out of the glenoid socket. Dislocations can happen anteriorly (out the front) or less commonly posteriorly (out the back). Sometimes the shoulder does not fully dislocate, but subluxates, or shifts partially out of the socket. Once dislocated, the shoulder may need to be reduced (put back in the socket) by a medical professional. Falls, sporting accidents, motor vehicle accidents, and other accidents can cause a shoulder dislocation. For those patients who experience recurrent (more than one) shoulder instability, the shoulder can even come out of place in their sleep or when doing simple everyday activities such as putting on their shirt.
Symptoms
Aside from the acute dislocation event, patients who have shoulder instability will oftentimes experience apprehension with their shoulder placed in certain positions. They may also experience pain deep inside the shoulder along with clicking, popping, and weakness. It can also be difficult to return to certain sporting activities with an unstable shoulder.
- Apprehension when the shoulder is placed in abduction and external rotation signifies an anterior labral tear with instability
- Pain in the back of shoulder when doing pushing activities or pushups can be a posterior labral tear
- Painful clicking with overhead activities can signal a superior labral tear.
- Difficulty with throwing can be caused by a postero-superior labral tear.
Diagnosis
A thorough physical examination will assess your strength, range of motion, and certain provocative tests can help narrow down the source of your symptoms. X Rays will evaluate for any fractures, bone loss, or arthritis within the shoulder. An MRI is typically also necessary to evaluate for a tear of the labrum within the shoulder. Depending on if there is any suspected bone loss, a CT scan is sometimes also required for operative planning.
Treatment
The type of shoulder instability, number of dislocations, sporting and work activities of the patient, and damage within the shoulder will help determine the course of treatment.
Physical Therapy
Strengthening the dynamic stabilizers of the shoulder and improving the biomechanics of the shoulder girdle can be effective treatment for many types of shoulder instability. This is particularly useful for superior (SLAP) labral tears and in overhead athletes. Physical therapy cannot heal a labral tear, but is aimed at improving the mechanics of shoulder function and can help alleviate pain and improve exercise tolerance.
Injections
Injections, including cortisone and PRP (platelet rich plasma), can also be utilized to lessen the pain from a labral tear. Injections do not have the ability to heal a tear.
surgical management
For those patients with recurrent dislocations (more than one dislocation and/or subluxation), and patients who have completed and failed other conservative treatments, surgery may be indicated.
Arthroscopic Labral Repair. The most common surgery to treat shoulder instability is an arthroscopic labral repair. Through a few small incisions, I repair the labrum back to the glenoid with a number of small anchors. This restores the stability of the shoulder in those patients who have minimal bone loss in their shoulder. The re-dislocation rate is generally less than 10% in properly selected patients, with high patient satisfaction and return to play rates. A typical return to sporting activity takes between 3-5 months depending on the sport.
Arthroscopic Remplissage. For patients with some amount of bone loss, and for patients with a large Hills-Sachs defect (a bone compression on the humeral head), another procedure can be added to a standard arthroscopic labral repair. This is still performed arthroscopically and helps lower dislocation rates further in certain at risk individuals. Part of the infraspinatus tendon is anchored into the humeral head defect. The rehabilitation is the same as after an arthroscopic labral repair, with lower redislocation rates in these more at-risk patients.
Latarjet Coracoid Transfer. When there is bone loss on the glenoid (socket side) there is a higher failure rate with soft tissue repair and reconstructive procedures (such as a labral repair). In these situations it is advantageous to reconstruct the socket with extra bone. The most common procedure for this is the coracoid transfer. A piece of bone called the coracoid is transferred to the front of the shoulder and secured in place with screws, thereby adding extra bone to the socket and deepening it. This helps prevent further dislocations by increasing the bony stability off the shoulder. This is done through an open incision on the front of the shoulder. Return to full sporting and work activities typically takes 4-6 months.
Shoulder Stabilization Surgery in Oregon
Dr. Daniel Elkin is a leading Orthopedic Surgeon performing Shoulder Surgery in the Willamette Valley. He specializes in complex shoulder reconstruction and shoulder arthroscopy and is conveniently located in Salem, Oregon