What is the likely diagnosis for a patient with acute shoulder pain at the tip of the left shoulder and no mechanism of injury?

• A. Rotator cuff tear
• B. Fractured collarbone
• C. Ruptured spleen
• D. Shoulder impingement syndrome

Answer: (C)

The symptoms described—a patient experiencing acute shoulder pain at the tip of the left shoulder without a specific mechanism of injury—can point towards referred pain from an internal organ, such as the spleen, rather than a localized shoulder issue. In particular, pain at the tip of the shoulder, also known as Kehr's sign, can be indicative of irritation of the diaphragm or splenic issues, as the phrenic nerve, which innervates the diaphragm, also refers pain to the shoulder region.

Conditions like a ruptured spleen often present with acute pain and might not have a clearly identifiable mechanism of injury, particularly if the rupture occurs from factors like splenic enlargement or certain medical conditions rather than direct trauma. This underscores the importance of considering internal organ pathologies when patients present with shoulder pain that is not clearly linked to a musculoskeletal injury.

In contrast, other listed options are typically associated with identifiable mechanisms of injury or specific clinical presentations that would not present solely with acute shoulder pain in the absence of injury. For instance, rotator cuff tears usually involve a specific mechanism, such as overhead activities or chronic degeneration, and fractures are generally accompanied by trauma. Shoulder impingement syndrome typically presents with specific functional limitations and pain that can often be