Acromioclavicular Joint Injury - Causes, Diagnosis and Treatment.

Introduction

The acromioclavicular joint or the AC joint, is a shoulder joint that articulates the clavicle to the scapula. The part of the scapula that meets the clavicle is known as the acromion hence the name acromioclavicular joint. Like several other joints in the body, cartilage is present between the bones, allowing them to move on without much friction.

What Are the Possible Ailments of the AC joint?

• Among several conditions, the most common conditions seen in the acromioclavicular joint are arthritis of the joint, fractures in the component bones, and separation of the joint components by dislocation.

• Arthritis is a condition characterized by cartilage loss in the AC joint. Wear and tear of the smooth cartilage occur with excessive overuse and degenerative diseases as signs of aging. As with other joints in the body, pain, and swelling, especially with activity, are commonly seen.

• In addition, the worn-out joint can expand over time, with spurs forming around it. These spurs are a sign of arthritis and do not cause symptoms such as pain. Instead, the pain aggravates trying to reach the other arm by stretching. This condition is common in weight lifters, especially those who bench press and, to a lesser extent, military press, resulting in a condition known as osteolysis.

What Is the Treatment for AC Joint Arthritis?

• If the articular cartilage is lost, it can in no way be replaced. Thus, one way to treat arthritis is to modify everyday activities to prevent the condition from aggravating. Giving up on such actions is not recommended but refraining from intense or repetitive strain to the joint.

• The use of ice and medication is also recommended in some instances. Ice application decreases pain and inflammation by applying directly to the joint for 20 to 30 minutes. Using an ice bag or massaging the joint with ice cubes or a cold gel pack can be effective. The joint, being relatively small, shows excellent pain relief with ice application.

• Anti-inflammatory medication such as Aspirin or other nonsteroidal anti-inflammatory drugs (NSAIDs) can be used, such as Ibuprofen, Naprosyn, Feldene, Clinoril, Daypro, Indocin, etc.

What Can Be Done if Ice and Medication Treatments Fail?

If rest, ice, medication, and modifying or reducing activities do not alleviate pain, the next step is a Cortisone shot or steroid injections to the joint to reduce inflammation. However, the effect of such therapy is unpredictable, sometimes questionable, and may not last for extended periods. Therefore, a surgical option may be considered when more than one or two cortisone shots fail. Mentioned below is the surgical option in detail.

• Surgery involves the removal of the spurs at the end of the collarbone since the pain occurs when the ends of the bones make contact with one another. The surgery can be performed using an arthroscope with a small incision about one inch long or several small incisions.

• The recovery phase and success results are about the same, regardless of the technique used. The patient can usually be discharged on the same day as the surgery by wearing an arm sling to immobilize the healing joint and prevent strain.

• The sutures removal is done on a follow-up visit about a week after surgery, and motion of the shoulder begins immediately after.

• The complete recovery takes about four to six weeks to regain the entire range of motion and another few weeks more to regain the original strength before the symptoms appear.

• Recovery depends upon several factors, but the patients mostly return to their completed activities in three months or less.

How Successful Is AC Joint Surgery?

Most patients get excellent pain relief postoperatively, with 95 % returning to the pre-injury activity level and sports within a few months. Although there are a few complications, as with most surgical procedures, most patients are satisfied with the results. The possibility of infection, although present, is infrequent. However, occasional fatigue or pain with extreme lifting or exercises may be seen.

What Is Joint Separation?

It is called joint separation or dislocation when the ligaments are torn, and the collarbone is no longer aligned with the acromion. The ligaments are tough, sinewy tissues acting as ropes to bind the bones together. A stretched or torn ligament can thus be excruciatingly painful.

Ligament injuries in an AC separation can cause mild to severe symptoms.

The injuries' grading depends upon the type and extent of the ligaments affected.

• Grade 1 Injury: This is where the damage is least done, and only the joint is injured.

• Grade 2 Injury: This signifies damage to both ligaments at the AC joint and other ligaments necessary for joint stability. This second set of ligaments is called the coracoclavicular ligaments, which attach the joint to the coracoid process. A grade 2 injury signifies stretching these coracoclavicular ligaments and not a complete tear. The collarbone and the acromion are misaligned if these ligaments are pulled from a lump at the joint.

• Grade 3 Injury: In this type of injury, the coracoclavicular ligaments are completely torn, and the collarbone is no longer bound to the shoulder blade. The misalignment of the collarbone with the acromion causes deformation of the joint site.

How Is AC Joint Separation Treated?

• Separation injuries can be harrowing, and the initial treatment is pain management. This is accomplished by immobilizing the arm and then applying an ice pack to the shoulder for 20 to 30 minutes every couple of hours and using pain medication directed by the consulting physician.

• Once pain management shows some success and starts to subside, it is essential to begin fingers, wrist, and elbow movements to prevent stiffness as directed by a physical or occupational therapist.

• Following this, shoulder motions should be initiated to avoid stiffness, commonly known as a "frozen" shoulder.

• The period necessary to regain entire movement and function depends upon the severity or grades of the injury, as discussed before.

• A grade one injury takes around ten to 14 days, whereas grade three takes six to eight weeks. A grade two takes somewhere in between.

What Are the Indications for Surgery in Case of Joint Separation?

A minimal number of grades one, two, and three injuries require no surgical interventions. Grade three injuries, being the most severe, usually allow a return to total activity with few restrictions on the excessive and repetitive strain. Rare variations of this injury in which the collarbone is at a higher level than usual and almost sticks out through the skin may require surgery. However, the risks and benefits must be taken into consideration.

• The advantage of such surgeries is that the deformity at the AC joint may be corrected but results in a scar formation.

• Disadvantages of this surgery are the risks of infection, a more prolonged recovery phase, and continued pain in some instances.

• Nevertheless, the success rate for surgery, where indicated, is incredible.

Conclusion

The acromioclavicular, commonly abbreviated as the AC joint, is present in the shoulder where the clavicle and the scapula articulate. Among several conditions, the most common conditions seen in the acromioclavicular joint are arthritis of the joint, fractures in the component bones, and separation of the joint components by dislocation. Most patients get excellent pain relief postoperatively, with 95 % returning to the pre-injury activity level and sports within a few months. Although there are a few complications, as with most surgical procedures, most patients are satisfied with the results.