Differential Diagnosis for Right Shoulder Pain
The patient presents with right shoulder pain that began 2 days ago without any direct trauma, characterized by a constant ache with sharpness upon movement. Here's a categorized differential diagnosis:
- Single Most Likely Diagnosis
- Rotator Cuff Tendinitis: This condition is a common cause of shoulder pain, especially in the absence of direct trauma. The sharp pain upon movement is consistent with inflammation of the tendons surrounding the shoulder joint.
- Other Likely Diagnoses
- Adhesive Capsulitis (Frozen Shoulder): Although it typically develops over time, the sudden onset of pain and stiffness could be an early sign. The constant ache and sharpness with movement are consistent with this diagnosis.
- Bursitis: Inflammation of the bursae around the shoulder joint can cause pain, especially with movement, making it a plausible diagnosis given the patient's symptoms.
- Shoulder Impingement Syndrome: This condition, where the shoulder blade puts pressure on the underlying tissues, can cause pain when moving the shoulder, fitting the patient's description of sharp pain upon movement.
- Do Not Miss Diagnoses
- Pulmonary Embolism: Although less common, referred pain from a pulmonary embolism can manifest as shoulder pain. Given the potential severity, it's crucial not to miss this diagnosis, especially if other symptoms like shortness of breath are present.
- Myocardial Infarction: Referred pain from a heart attack can sometimes be felt in the shoulder. This is a critical diagnosis not to miss due to its high mortality rate if untreated.
- Pancoast Tumor: A tumor at the apex of the lung can cause shoulder pain due to invasion of the brachial plexus or ribs. While rare, missing this diagnosis could have severe consequences.
- Rare Diagnoses
- Septic Arthritis: An infection within the shoulder joint, which could cause severe pain, especially with movement. It's less common but should be considered, especially if there are signs of infection or systemic illness.
- Osteonecrosis: Death of bone tissue due to lack of blood supply can cause shoulder pain. It's a rare condition but could be considered, especially if the patient has risk factors like long-term steroid use or excessive alcohol consumption.
- Polymyalgia Rheumatica: An inflammatory condition that can cause widespread muscle pain, including the shoulder area. It's less common and typically affects older adults, but it should be considered in the differential diagnosis due to its potential for significant morbidity if untreated.