Shoulder Injuries

Shoulder injuries are common in vehicle related accidents. In vehicle accidents, they commonly occur from bracing against the steering wheel, dashboard, or back of the seat. They also commonly occur due to the seatbelt “jerking the shoulder backwards” or direct impact against the door/window. Fractures of any of the bones involving the shoulder area can occur, but are less common, and for the sake of this discussion I will defer these to my orthopedic surgery colleagues. The common injuries that we see are rotator cuff, labral, and acromio-clavicular (AC) injuries. Let’s discuss them one at a time. 

  1. The rotator cuff are a group of muscles and their tendons that surround the shoulder joint and provide the majority of the movement, as well as some of the stability of the shoulder. Each “fleshy muscle” thins down to form a tendon just prior to the tendon attaching to a bone. The commonest rotator cuff injury is of the supraspinatus muscle/tendon. The muscle lies over the upper part of the scapula and its tendon runs through a bony canal underneath the AC joint and attaches onto the outer side of the top of the humerus. In an injury it is very common for this tendon to become swollen, causing tendinitis. This leads to a pinching of the tendon in the bony canal underneath the AC joint. The patient usually describes this as a “catching” or a “grabbing pain”, particularly as they move their arm sideways towards the ear. Partial and complete tears of this tendon can also occur. If a complete tear occurs, surgery is the only form of management that will give a good recovery. Complete tears, however, are uncommon. Much more common are small partial tears or tendinitis. These respond well to conservative management including ice, anti-inflammatories, cortisone via a patch (iontophoresis) or by injection into the shoulder joint, and laser therapy. Manual physical therapy including range of motion exercises, nerve release techniques, and postural reeducation is also extremely helpful. The vast majority of patients respond to this conservative management. If the patient does not respond in three to six weeks, an MRI scan is performed to evaluate the possibility of a complete tendon tear or labral tear. If evidence of rotator cuff injury is noted, referral to an orthopedic surgeon will be made for probable cortisone shot and/or surgery.

  2. Now let’s discuss a labral tear. The shoulder is a ball-and-socket joint. Unlike the hip, which is very stable, the shoulder has a large ball and a small, flat socket. To assist with stability, a large cartilage cup called the labrum surrounds the ball of the humerus. A crack or tear of the labrum can cause deep-seated shoulder pain. It is commonly missed on routine MRI scans (some experts say up to 80% of the time). To definitively diagnose this injury requires an arthrogram followed by a MRI scan. An arthrogram is the injection of a liquid dye material into the shoulder joint. This lines the crack or tear, which is then easily seen on an MRI scan. The reason an arthrogram is not performed routinely, is that the dye can cause allergic reactions. A labral tear usually does not respond to conservative management and requires surgery for a successful result to be obtained.

  3. Lastly, let’s discuss AC injuries. This joint is formed by the outer clavicle joining the acromion. It is essentially the “tip” of the shoulder. It forms the roof of the “bony canal” that the supraspinatus tendon travels through. The ligament or elastic tissue joining the two bones can stretch in an injury, thus causing AC joint “separation”. In its milder forms this causes pain and clicking at the tip of the shoulder, often made worse with movement. In the severest form, the ligaments that hold the joint together will be so stretched that a “step-off” can be seen. The vast majority of these injuries heal well with conservative management including ice, anti-inflammatories, and manual therapy, which include special taping techniques, for one to two months. It is extremely rare that surgery needs to be considered for an acceptable result to be obtained.

Shoulder injuries are extremely common in vehicle related accidents. The vast majority can be treated successfully with a step-by-step conservative approach as noted above. A small percentage will, however, require surgical repair. This surgery is painful and usually requires a four to six-month recovery period. This usually includes the initial use of a sling for four to six weeks, aggressive physical therapy for an additional four to eight weeks, and then the need for compliance with a home program for an additional few months. Depending on your kind of work, this could significantly interfere with your ability to perform it. The decision to undergo shoulder surgery shoulder never be taken lightly. Fortunately, the results six months after surgery are considered good/excellent by the vast majority of patients.

A Better Way to Get Better,
Adrian Lewis
Adrian Lewis, MD