S43.15

Clinical Causes: Posterior dislocations of the acromioclavicular joint often result from trauma or impact injuries. Common causes include: - Direct blows to the front of the shoulder, such as during a fall onto the shoulder, a sports collision, or a motor vehicle accident. - Fall onto an outstretched arm with force transmitted through the shoulder. - Forceful impacts or trauma during contact sports like football, rugby, or hockey. - Falls that cause the shoulder to be compressed backward. In some cases, injuries may occur during high-impact accidents or falls where the shoulder is pushed from the front, forcing the clavicle backward relative to the acromion.

Key Symptoms: Individuals experiencing a posterior acromioclavicular joint dislocation may notice several symptoms, including: - Sudden onset of shoulder pain, especially after trauma. - Visible deformity or swelling around the shoulder joint. - Tenderness and sensitivity in the shoulder area. - Reduced range of motion, making it difficult to lift or move the arm. - A sense of instability or shoulder dislocation. - Possible numbness or tingling if nerves are affected due to displaced bones. - Difficulty performing daily activities that involve shoulder movement.

Diagnosis Path: Diagnosing a posterior acromioclavicular dislocation typically involves several steps: - Medical history review, focusing on recent trauma or injuries. - Physical examination to assess shoulder deformity, swelling, tenderness, and range of motion. - Special physical maneuvers, such as the cross-body adduction test. - Imaging studies, primarily X-rays, to confirm the dislocation and its direction. - Sometimes, additional imaging like MRI or CT scans may be used for detailed evaluation of the injury and to rule out associated injuries. Accurate diagnosis is critical for determining the appropriate treatment plan.

Treatment Protocols: Treatment options for posterior acromioclavicular joint dislocation depend on the severity of the injury: - Conservative management: Mild dislocations may be treated with rest, ice application, and immobilization using a sling or shoulder brace. Pain relief is achieved through medications such as NSAIDs. - Physical therapy: Once initial pain subsides, targeted exercises are recommended to restore shoulder strength and mobility. - Closed reduction: For significant displacements, a healthcare professional may perform a procedure to realign the clavicle into its proper position. - Surgical intervention: Severe or recurrent dislocations, or those with associated injuries, might require surgery. Procedures may involve repairing or reconstructing ligaments, fixing fractured bones, or stabilizing the joint. - Rehabilitation: Post-treatment, a structured rehabilitation program is essential to regain full shoulder function and prevent future dislocations. Early diagnosis and proper management are vital for optimal recovery and minimizing long-term complications.