Early in Iowa's fall camp, freshman running back Marcus Coker sustained a clavicle fracture, which kept him on the sidelines for several weeks. This weekend he will likely make his season debut for the Hawkeyes at running back. In our weekly series for fans to understanding sports injuries and the rehabilitation process, Dr. Michael Tunning goes in-depth on clavicle fracture and returning to the playing field from these type of injuries.

Clavicle Fractures

Clavicle (also known as collarbone) fractures are common injuries that occur in contact sports and in motor vehicle accidents. The clavicle extends from the sternum to the shoulder in an "S" shape, acting as a strut to keep the shoulder and arm away from the sternum and thoracic cage, helping to stabilize the shoulder girdle, and allowing the arm a full range of movement. In addition to the multiple muscle attachments on the clavicle, it also provides protection to vital neurovascular structures. When the clavicle is fractured, it is necessary to make sure the broken ends of the bone are not compromising the neurovascular structures it protects. There are three areas where a break occurs: the medial portion (closer to the sternum), the distal portion (closer to the shoulder), and the middle portion (in between the medial and distal zones).

Injury often occurs when there is a direct force applied to the shoulder or from falling on an outstretched arm. With contact sports like football, it is most commonly found when the athlete is tackled and lands on their side, primarily on the shoulder. (Interesting side note: clavicle fractures were the most common fractures that occurred on RAGBRAI from data collected 2004-2008. Most likely due to falling off the bike onto the shoulder.) The force of the tackle is transmitted through the collarbone, the "S" shape makes the forces overload the middle section of the bone. This is likely why 70-80% of clavicle fractures occur in the middle portion. Once the bone is fractured, it is easily visualized with a lump and swelling over the involved area. The clavicle is a superficial structure, so any bump or alteration to the bone is very identifiable. When the athlete explains to the sports medicine staff what happened you commonly see them palpate along the clavicle to feel for any disruption in the normal contour of the bone. In football players this means the athletic trainer will go under the shoulder pads to feel along the bone. After the fracture occurs, other signs and symptoms present include pain, often severe sagging of the shoulder in a down and forward position, and an inability to lift the arm due to pain. After the initial injury, the arm of the affected clavicle is placed in a sling and immobilized. Healing times depend on age; in adults, healing could take up to eight weeks, in younger individuals it may take six.

The major objectives of rehabilitating a clavicle fracture are to:

- increase flexibility in the shoulder

- establish pain-free range of motion in shoulder

- strengthen the muscles of the shoulders, upper back, chest, and upper arms.

Maximum Protection Phase

Initially the shoulder will be immobilized with the arm in a sling. Ice is used to help reduce pain and inflammation. When the arm is out of the sling without pain, the athlete can progress into more activity. Exercises in this phase focus on keeping movement. Pendulum-type exercises called Codman's exercises are utilized. This very simply is the athlete bent at the waist, allowing the arm to hang freely while small movements back and forth and in clockwise/counterclockwise movements are performed.

Moderate Protection

As healing progresses and no pain is present with movement, more involved exercises can occur. Arm movements that help to strengthen the muscles of the chest and back (like bicep curls, arm raises, tricep extensions, and shrugs) are initiated without the use of weights. These movements are gradually increased in demand; incorporating underwater resistance, thera-bands, and ultimately weights.

Return to Play

Return to full participation should be avoided until the fracture is healed - as evident on x-ray - and movements of the shoulder are equally strong compared to the other side. When performing the skills specific to the sport, no pain should be present. If an athlete returns before strength is back or the fracture is healed, there is a higher incidence of re-injury. This is especially true when the sport involves heavy contact, such as with a running back that could be tackled on a previously injured shoulder.

Generally, the athlete who wishes to return to a contact sport should expect to be out of action for 6 to 12 weeks. The time to return to full activity depends on the severity of the injury, dedication of the athlete to remain in a rehabilitation program, position the athlete plays, and strength of the athlete. It is important to evaluate each athlete on an individual basis.

Michael Tunning D.C., ATC

Dr. Tunning is a faculty member at Palmer College of Chiropractic in the Diagnosis and Radiology Department. He also is an Associate at Chiropractic Healthcare Associates in Cedar Rapids, IA focusing in all musculoskeletal injuries as well as athletic injuries. Dr. Tunning is a member of the Iowa Athletic Trainer's Society, the Iowa Chiropractic Society and is a member of the American Chiropractic Association's Sports Council working as the liaison to the National Athletic Trainer's Association.

For more information please visit www.chiroassoc.com