Shoulder pain and the acromioclavicular joint/AC joint
If you are experiencing pain on the top of your shoulder you may well have a problem with your AC joint. I have found this to be particularly common in trades-people and those with a history of a lot of physical work.
What is the acromioclavicular joint?
The AC joint is located on the top of the shoulder and joins the collar bone (clavicle) to the shoulder blade (scapula). It’s quite a small joint and if you are feeling pain here you may even think the pain is in the bone! The AC joint plays an important role in shoulder function and is involved in a lot of different movements including bringing the arm over head. This is why it can be aggravated in people spending time working with their hands above their heads, for example, painting a ceiling.
How does it get damaged?
The AC joint has many ligaments that support it, and it also contains a cartilage disc (similar to the discs in your back) in between the joint surfaces. This disc acts to protect the joint surfaces and allow movement, it maintains a good distance between the bones that make up the joint and ensures that they don’t come into contact. However beyond the age of 40, this disc slowly degenerates. It can also be damaged through instability, trauma (this commonly happens during a rugby tackle!) or infection. These can cause fraying and tearing of the disc, which encourages it to wear away.
This wear and tear of the disc leads to the joint surfaces coming closer together and causing the ends of the bones to become a bit too close. In response the collar bone and shoulder blade develop little bony spurs which can catch the surrounding tissues and cause pain. This can also cause the surrounding tissues to develop methods of compensation in order to avoid damage or pain, in other words you may find that you are not using your shoulder properly and are avoiding certain movements. This can lead to further problems in the surrounding tissues as some muscles may be over used and others not at all.
What can be done to help?
Physical therapy such as osteopathy can be helpful for AC joint problems. Treatment to the area will encourage an increased blood supply which will help the joint to heal and repair. Gentle, passive movement of the joint surfaces can also help with fluid exchange through the joint, which will also encourage healing. Techniques can also be applied to the surrounding tissues to relieve secondary problems that have developed as a result of an impaired use of the shoulder. I would also recommend using heat and ice in order to help with pain relief.
If the joint is too damaged for remedy through physical therapy, other options are available. These include anti-inflammatory medication, corticosteroid injections that help to reduce inflammation in the joint, and surgery in order to increase the space between the joint surfaces and stop them coming in to contact.
- Gancarczyk, S, M., Ahmed, C, S.(2014) Acromioclavicular arthritis and osteolysis Operative Techniques in Sports Medicine. Volume 22, Issue 3, Pages 214-220
- Favorito, P, J., Herbst, K, A. (2015) Acromioclavicular joint injuries Shoulder and Elbow trauma and its complication http://dx.doi.org/10.1016/B978-1-78242-449-9.00010
- Keener, JD. (2014) Acromioclavicular joint anatomy and biomechanics Operative Techniques in Sports Medicine Volume 22, pages 210-213
For further information or to book an appointment call Rosie on 07540 453280 or visit www.swanseabodykinetics.co.uk