Rotator Cuff Injuries

Rotator Cuff Tears

Primnal Cuff Front ViewThe rotator cuff is a group of four muscles (supraspinatus, infraspinatus, teres minor, and subscapularis) that work together to rotate the shoulder and to hold the humerus in the center of the glenoid socket. These muscles are small, and lie underneath the larger muscles of the shoulder such as the deltoid, trapezius, and pectoral muscles. They connect to the humerus via tendons. It is the tendon part of the rotator cuff that is usually inflamed or torn.

Rotator Cuff Tendonitis

Primnal Cuff SideViewAnytime a muscle / tendon is overworked, it will become inflamed. The rotator cuff is frequently inflamed in throwers, along with the bursa that sits on top of the cuff. This tendonitis and bursitis is usually not dangerous but can be painful. The diagnosis requires a physical examination by a qualified Sports Medicine physician, and occasionally an MRI. The MRI is actually to rule out more severe problems such as a rotator cuff tear. The treatment is usually relative rest (decreasing but not stopping activities), anti-inflammatory activities, and physical therapy. The idea is to allow the overworked cuff a chance to recover and heal, diminish the inflammation, and strengthen the cuff so it can better tolerate the activities in the future.

MRI of Rotator CuffIf the rotator cuff is overworked for a long time, it may start to fray or tear, just as a rope that is pulled too hard too many times may fray and tear. In the thrower it is rare for the cuff to suddenly tear through and through, but it can happen gradually. Usually, the pain gets too great to pitch long before the tear penetrates all the way through the cuff tendon. It is interesting that this fraying is not always painful. Sometimes it is the inflammation (rather than the fraying) that hurts. Most Major League pitchers will have some visible evidence of fraying of the rotator cuff on their MRIs, but this is not always painful! A thorough evaluation by an experienced shoulder physician is necessary to determine this. A MRI can tell us if the rotator cuff is frayed or partially torn, but it can’t tell us if that actually hurts! The history and physical examination are just as important in diagnosing a shoulder problem in a thrower.

Internal Impingement

Internal impingement is one of the problems seen in throwers’ shoulders. If the shoulder goes too far in ER/extension during the cocking phase (i.e. elbow behind the chest with the shoulder externally rotated), the rotator cuff will get pinched inside the shoulder (impinged internally) between the glenoid and humerus. This can result in some partial tearing of the rotator cuff which can progress to a serious tear. The internal impingement is made worse by an unstable shoulder, “SICK” Scapula, and also by loss of internal rotation (GIRD, see below). Since most of these risk factors can be addressed by physical therapy and improving throwing mechanics, surgery can be avoided if it is detected early enough.

Rotator Cuff Surgery

Rotator Cuff Tear

Rotator Cuff Tear

If the rotator cuff tendon is partially torn, sometimes rehabilitation doesn’t work and surgery is necessary. If the rotator cuff is torn completely, surgery is almost always needed. The surgery is arthroscopic and done as an outpatient. The rotator cuff must be repaired and reattached to the bone from which it detached, and any underlying problems must be fixed too. Sometimes the rotator cuff tears because of instability in the shoulder (see below)—if this is the case the shoulder must be tightened or the cuff will re-tear.

Rotator Cuff Repair

Rotator Cuff Repair

I reattach the rotator cuff tendon to the bone using “suture anchors”. These are dissolvable screw tips that I embed into the bone. They fasten the suture to the bone, then the suture can be sewn into the rotator cuff tendon to tie it to the bone until it heals.

Rotator Cuff Corrected

Rotator Cuff Corrected

Once the tendon has healed to the bone, the sutures and the suture anchor are superfluous. Over time the anchor will dissolve (usually a few years). However, it takes about six weeks for the cuff to heal enough to start using the shoulder for daily activities or for any strengthening activities. So, a shoulder immobilizer must be work for six weeks after surgery. This is to protect the repair from pulling apart. Some patients think they will get better quicker if they push the envelope by going without the immobilizer. In fact, they are jeopardizing the repair by pulling on the sutures with every little movement of the shoulder. The sutures are strong, but little movements add up by wiggling the sutures loose, and once they are loose the repair separates and will not heal. So, discipline is important to get a good result.

Dr. David Lintner - Houston Orthopedic Surgeon