Yes. A shoulder MRI visualizes the acromioclavicular (AC) joint, including cartilage, joint space, ligaments, surrounding soft tissues and bone marrow. MRI detects AC joint osteoarthritis, sprain/separation, inflammation, effusion, cysts and associated rotator cuff or labral pathology. Plain radiographs remain useful for bony alignment and osteophytes, but MRI offers superior soft-tissue detail.

The left acromioclavicular (AC) joint is where the collarbone (clavicle) meets the acromion of the shoulder blade (scapula) on the left side. It stabilizes the shoulder girdle, allows arm elevation and rotation, and transmits forces from the arm to the chest. Ligaments (acromioclavicular and coracoclavicular) support it. It can be injured or develop arthritis, causing pain and limited movement.

On MRI, a normal acromioclavicular (AC) joint space is typically about 1–3 mm. Small side-to-side differences are common. Measurements over roughly 3–4 mm suggest AC joint widening (trauma or instability), while marked narrowing or irregular joint surfaces indicate degenerative osteoarthritis. Imaging findings should be correlated with clinical signs and other studies for accurate diagnosis.

Acromioclavicular (AC) joint damage often does not require surgery. Most mild to moderate injuries and arthritis respond to rest, immobilization, anti-inflammatories and physiotherapy. Surgery is considered for severe displacements (high-grade AC separations), persistent pain or instability after conservative care, or in high-demand athletes; procedures include ligament reconstruction or distal clavicle excision. Decision depends on injury severity and functional needs.

Repair begins with accurate diagnosis (exam and imaging). Mild AC injuries are treated conservatively: rest, ice, sling, NSAIDs and progressive physiotherapy to restore range of motion and strengthen rotator cuff and scapular stabilizers. Severe or unstable separations may need surgery—ligament reconstruction, clavicle fixation or distal clavicle excision—followed by immobilization then staged rehabilitation to regain motion and strength.

MRI is not routinely required for shoulder pain. Begin with clinical assessment and basic imaging (X‑ray or ultrasound) and try conservative care (rest, physiotherapy, pain relief). MRI is considered if symptoms or functional loss persist despite treatment (typically 4–12 weeks), or sooner when there’s suspected full‑thickness rotator‑cuff tear, major trauma, instability, progressive weakness, or for surgical planning.