AC Joint Injury are common. There are around 300 joints in the human body and many of them are susceptible to what we commonly think of as injury. Not all of them are; technically the plates that form the skull create joints, for example, but we don’t think of these in the same way as joints in the neck, shoulder, hip, knees and ankles that are prone to injury.

Most of the injury to these joints occurs as a result of repetitive stress or trauma. One common form of joint injury is the ankle sprain, which occurs when the ligaments that hold the ankle together, are torn or stretched. This causes pain, swelling and sometimes immobility of the joint. These injuries occur frequently during athletic activities.

The symptoms associated with an ankle sprain are commonly known, and include pain in the injured area, swelling and an inability to support weight on the ankle. There is also sometimes redness and swelling around the ankle. Diagnosis is done with the use of imaging technology like X-ray, MRI and CT scans. Treatment involves activity reduction, splinting and walking aids like crutches. Physical therapy is also sometimes called for. Surgery is required in only the most serious cases.

We are going to focus the remainder of this article on two other common forms of joint injury, the AC joint and SI joint injuries.

AC Joint Injuries

Shoulder separations are a common form joint injury, and happen frequently during sporting activities like rugby and football. They are also commonly caused by falling off a bicycle. Shoulder separations occur at the acromioclavicular (AC) joint, which is positioned at the top of the shoulder.

The shoulder is made up of three bones: the clavicle (collarbone), the scapula (shoulder blade) and the humerus (arm bone). The joint socket is formed by the scapula and clavicle; the humerus sits inside that socket. A shoulder separation occurs when the clavicle becomes separated from the joint. This is also called AC separation.

Shoulder dislocations are different than AC joint injuries, though the two are often confused with one another. Shoulder separations usually occur as the result of trauma that is sudden, sharp and forceful. Symptoms include severe pain, swelling and bruising of the area. Bumps above the affected area are present in more severe cases.

Shoulder separations are diagnosed with via X-ray to ensure that there are no associated fractures, but the injury can usually be diagnosed by listening to how it occurred and the description of the pain.

Severity of AC Joint Injuries

There are different levels of severity of shoulder separations:

Type I separation occurs when the bones are not out position but pain is present.

Type II separation includes a partial tear of the coracoclavicular ligament, and may result in a small bump over the injury.

A type III separation is the same as a type II only more severe. It is often marked by a large bump over the area.

Type IV separation occurs when the clavicle is pushed behind the AC joint.

Type V separation is very serious case of the type III injury, in which the muscle above the AC joint is damaged by the end of the clavicle. A significant bump is seen over the area.

Type VI separation is very rare, but occurs when the clavicle is pushed down and becomes stuck below the scapula.

Treatments of AC Injury

The joint should be iced for 15 minutes every four hours for the first several days after the injury, and the joint should be rested. With serious swelling, anti-inflammatory medications might be prescribed. Surgery is sometimes required and nearly always in the cases of Types IV, V and VI separations.

SI Joint Injury

SI joint injury are also fairly common; they involve the sacroiliac joint, which lies at the joint of the pelvis and spine. The joint plays an important role in bearing and managing the load between your upper and lower body.

SI joint injury symptoms include pain and tenderness in the area. Diagnosis can be difficult because the symptoms are much like common types of back problems and because tests to not generally isolate SI joint.

X-ray and other imaging tests are often run to isolate the problem and in some cases a numbing agent is introduced into the joint. If pain subsides, this is a clue that there is an issue with the joint.

Treatment of SI injury involves reduced activity, anti-inflammatory medication and physical therapy, which is used to strengthen the muscles around the joint, and increase flexibility in the area. Cortisone is sometimes used in cases where other treatments fail. Cortisone injections deliver a more powerful punch of anti-inflammatory agent directly to the site, and thus can help with particularly difficult cases. The key is to reduce the inflammation so that normal activity can be restored.

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