Acromioclavicular and Sternoclavicular Joint Pain

Definition/diagnostic criteria Acromioclavicular (AC) joint pain refers to discomfort or pain stemming from the joint formed by the acromion of the scapula and the clavicle. Sternoclavicular (SC) joint pain originates from the joint between the sternum and clavicle. Diagnosis often involves clinical assessment and may include imaging.

Epidemiology AC joint pain is commonly associated with young athletes engaged in contact sports, while SC joint pain is less common and can affect individuals following trauma or due to inflammatory conditions. In the UK, the incidence of these conditions aligns with global patterns, where AC joint disorders are more prevalent than SC joint issues.

Diagnosis
Clinical features:

• AC joint: Localised tenderness and swelling over the joint, pain exacerbated by cross-body movements or lifting, and sometimes visible deformity in cases of dislocation.
• SC joint: Pain and swelling over the joint, exacerbated by arm movements or lying on the affected side. In severe cases, there may be a noticeable bump or depression.

Investigations:

• Imaging: Radiographs are the first-line imaging modality; ultrasound or MRI may be employed for further evaluation.
• Typical abnormalities: Radiographs may reveal joint space widening, arthritic changes or, in cases of trauma, dislocation/subluxation.

Treatment

• Conservative treatment: Includes rest, ice, physiotherapy and NSAIDs. For AC joint injuries, a sling may be used for immobilisation.
• Medical treatment: Initial management of both conditions includes pain relief (such as NSAIDs) and activity modification. In refractory cases, corticosteroid injections may be considered.
• Surgical treatment: Indicated in persistent cases or severe injuries. For AC joint, procedures may include resection of the distal clavicle or ligament reconstruction. SC joint surgeries are less common and more complex, often reserved for severe cases.

Prognosis The prognosis for AC and SC joint pain is generally good with conservative management. Most patients with AC joint issues recover with non-surgical treatment. However, persistent pain or instability may require surgery. In SC joint pathologies, conservative management is often sufficient, but recovery may be prolonged in severe cases.