AC Joint Injury / Collar Bone Injury
What is an AC Joint Injury?
The AC (acromioclavicular) joint is a joint in the shoulder where the collarbone (clavicle) meets the shoulder blade (scapula).
AC joint injury causes
Your AC joint can be injured from direct trauma, such as when playing contact sports, or falling onto it. The resulting injury can be anything from a simple sprain of the joint, to a complete dislocation and separation of the two ends of the joint.
There are 6 grades of AC injury to describe the extent of damage:
- Type 1: Sprain of the AC ligament but the CC (coracoclavicular) ligament is intact
- Type 2: Complete tear of the AC ligament with a sprain of the CC ligament
- Type 3: Complete tear of the AC and the CC ligaments with upward displacement of the clavicle of 25% - 100%
- Types 4 – 6: These grades describe the different directions the clavicle is sitting after being dislocated
AC joint injury symptoms
Typically when your collar bone is injured, pain is felt immediately over the joint, which is on top of the shoulder. There is usually a background ache, and sharp pain on movement of the shoulder (particularly when shrugging the shoulder), and reaching across in front of the body or above the head.
In cases where a more severe injury has been sustained, (type 2 – 6) there will be an obvious bump or deformity on top of the shoulder. The more severe the injury, the bigger the bump.
AC joint injury treatment
Types 1 – 2
- RICE (Rest the affected area, apply Ice to the painful area, Compress the affected region, however Elevation isn’t requires in this case)
- Sling
- Taping to support the joint
- Nonsteroidal anti-in ammatories may be appropriate
- Manual Therapy to restore normal movement to the joint
- Strengthening and exibility exercises
Type 3
- Unless your are an athlete, particularly one who competes in throwing sports, management is identical to Type 1 and 2 injuries
- If you are an athlete as described above, or if symptoms do not settle or function is limited, surgery may be required. This is not always clear cut, and there is some controversy surrounding the success rate of this surgery
Types 4 – 6
- Require early surgical management