A - C Sprain
The A-C or Acromioclavicular Joint is a synovial joint that provides the only bony attachment of the arm to the axial skeleton. It is comprised of the clavicle (collar bone) and the acromion process of the scapula (shoulder blade). When this joint is injured, normal arm movement and function is severely limited. The joint functions as a strut, providing a pivot point for the scapula and thoracic vertebrae. As the arm is raised, the scapula rotates away from the spine, the A -C joint provides the pivot point for this to occur. Three ligaments support this joint: the acromioclavicular ligament and two coracoclavicular ligaments.
The most common mechanism of injury is falling on a out-stretched arm, using the arm to catch one’s self. The force of falling “jams” the head of the humerus into the A - C joint above. The resulting force sprains or tears the three ligaments (seen to the right) holding the joint together. Another mechanism of injury is to fall on or have a direct blow to the joint. This causes the clavicle to be pushed down spraining the joint.
As with any injury, the severity dictates the treatment. A basic grading system is Mild, Moderate, and Severe (Grade I, II, or III). The table below illustrates the severity differences.
A grade I sprain is first treated by removing the athlete from the sport in question if he/she is unable to continue to play. If the athlete is able to continue play, a protective pad should be placed over the joint to minimize the chance of further injury.
If the athlete is unable to continue, the RICES (Rest, Ice, Compression, Elevation, Support) principle should be employed. Ice the injury and place the athlete in a sling. Since the A- C joint is a strut, the weight of the arm needs to be removed from the joint. A sling will make the athlete more comfortable. If a sling is not available use an elastic wrap to secure and support the arm. If nothing is available, have the athlete place his/her hand in the waist band for their pants or shorts. Over the counter medications such as Advil® or Aleve® should be given to decrease pain and control inflammation.
Range of motion exercises should be instituted the day after injury. Strengthening exercises are begun as pain allows. The athlete will often be able to resume full activities after 7 to 10 days. If the athlete is unable to perform rehabilitation exercises after 2 to 3 days, an orthopaedic surgeon should be consulted. The joint should be padded prior to return to contact activities.
If a player sustains a 2nd degree sprain, he/she should be evaluated by an orthopaedic surgeon to determine the severity of the injury. Many times with a grade II sprain a small fracture may be present. As pain allows, the athlete should begin rehabilitation exercises to increased range of motion and restore normal strength. These individuals should not be allowed back to full activities until cleared by the orthopaedic surgeon. Often times this grade of injury will result in 4 to 6 weeks of time loss.
These athletes, as with grade II suffers, should be removed from the sport activity. They must seen an orthopaedic surgeon to determine if surgery is needed to repair the injury. If surgery is required, the athlete will be done for 10 -12 weeks.
Surgery involves reattaching the torn ligaments with suture. In some instances, a screw may be used to hold the clavicle in place while the repaired ligaments heal. The graphic below shows one possible type of repair.
Rehabilitation exercises should consist of gentle passive motion followed by active motion. Motion in the planes of flexion, abduction, extension, and internal and external rotation are utilized. Also strength training for the biceps, triceps, trapezius, deltoids, and forearm muscles should be added as the physician allows. Remember the goal of rehabilitation is to restore the athlete to full strength and full function.
©2000 - 2009 David Edell
Information on this site is not a substitute for physician directed care.
Please consult your personal physician for more detailed information
concerning specific injuries or illnesses.
Last Update for AthleticAdvisor.com: 10/24/2009 12:09:35 AM