Acromioclavicular Sprain Sidelines Bradford
MRI Will Determine Severity of Shoulder Sprain
Sep 6, 2009
Last season’s Heisman Trophy winner, Sam Bradford, was injured late in the first half after being tackled by linebacker Coleby Clawson. The Sooners’ quarterback was tended to on the field by the athletic training staff and then removed from the game (Associated Press, Los Angeles Times, September 6, 2009).
The early diagnosis from the medical team is that Bradford suffered a sprain to his right acromioclavicular joint (AC joint) after being tackled and landing full force on his right shoulder.
An MRI will determine the severity of the sprain. The term “sprain” denotes injury to a ligament. Ligaments provide bone-to-bone stability. Damage to a ligament can compromise the integrity of a joint leading to joint instability. The severity of the injury depends on the number of ligaments injured within a joint and the amount of the ligament damage.
Although this specific joint within the shoulder does not have the ability to move in a wide degree of directions like the glenohumeral joint, its ability to glide up and down and front and back are critical to the movement of the shoulder. Without it, the motion of the glenohumeral joint would be limited.
Anatomy of the AC Joint
The acromioclavicular joint is an articulation between the distal end of the clavicle and the acromion process of the scapula. The AC joint is located at the tip of the shoulder and can easily be palpated by following the end of the clavicle until it meets with the acromion process. The two bones should be flush in a healthy shoulder.
The AC joint has three strong ligaments that form a triangle to stabilize the clavicle to the acromion process. Each ligament contains the name of either the process of the bone or the bone it attaches to. They include:
- acromioclavicular ligament (attaches from acromion process to the clavicle)
- coracoclavicular ligament (coracoid process of the scapula to the clavicle)
- coracoacromial ligament (coracoid process of the scapula to the acromion process of the scapula)
Types of AC Sprains
Ligaments can be slightly stretched (first degree sprain), partially torn (second degree sprain) or completely ruptured (3rd degree).
A first degree AC sprain would result in mild, localized swelling and pain directly over the AC joint specifically if the arm is raised past 90 degrees. Because a first degree sprain results in no loss of stability, the limitation to the athlete is his/her own pain tolerance.
A second degree AC sprain is more severe with partial damage to one or more of the three ligaments, but with the coracoclavicular ligament still intact. The coracoclavicular ligament maintains vertical stability of the clavicle. A small step may be felt between the acromion process and the clavicle in a second degree sprain with the clavicle being slightly raised.
The second degree sprain is more limiting to the athlete. The signs and symptoms might include moderate swelling, increased pain with and without movement of the shoulder, and a small step deformity of the clavicle. This type of injury would sideline an athlete for several weeks.
A third degree sprain is the most severe and includes a complete rupture of both the acromioclavicular and coracoclavicular ligaments. A significant deformity would be seen with the distal end of the clavicle dislocated significantly above the acromion process. Other damage may include intra-articular disc damage and possible fracture to either the clavicle and/or acomion process. Because the amount of tissue damage is extensive in a third degree, the athlete would be out of competition for weeks.
Treatment of AC Sprains
First and second degree sprains are treated conservatively with ice, rest, immobilization (one to three weeks depending on severity), and nonsteroidal anti-inflammatory drugs (NSAIDS). As the pain diminishes, gentle range-of-motion exercises can be performed as tolerated to gradually increase the movement of the shoulder.
A third degree may require surgery to reduce the dislocated clavicle and surgically stabilize the joint. Immobilization may be as long as six weeks followed by extensive therapy to gradually regain mobility and strengthen the shoulder. Once the strength is back, functional exercises can be started to get the athlete ready to return to activity.
 |
