Differential Diagnosis for Left Shoulder Pain
The patient presents with left shoulder pain radiating to the arm, limited range of motion, and point tenderness, which suggests a musculoskeletal or orthopedic issue. However, her significant past medical history, including aortic valve replacement and anticoagulation therapy, necessitates consideration of other potential diagnoses.
Single Most Likely Diagnosis
- Subacromial Bursitis or Rotator Cuff Tendinitis: Given the patient's history of right shoulder tendonitis, recent arm exercises, and the nature of her pain, this diagnosis is highly plausible. The pain pattern, limited range of motion, and point tenderness over the anterior/lateral shoulder are consistent with inflammation of the rotator cuff tendons or the subacromial bursa.
Other Likely Diagnoses
- Adhesive Capsulitis (Frozen Shoulder): Although less likely given the acute onset, the patient's limited range of motion and history of shoulder issues could suggest early stages of adhesive capsulitis.
- Muscle Strain: The patient's recent increase in arm exercises could have led to a strain of the muscles around the shoulder, contributing to her pain.
- Referred Pain from the Cervical Spine: Cervical spine disorders can refer pain to the shoulder and arm, but the absence of neck pain or other cervical symptoms makes this less likely.
Do Not Miss Diagnoses
- Thoracic Aortic Dissection: Given the patient's history of aortic valve replacement due to aortic stenosis with a bicuspid valve, there is an increased risk of aortic dissection. Although the patient denies chest pain, aortic dissections can sometimes present atypically, especially in patients with altered pain perception or those on anticoagulation therapy.
- Pulmonary Embolism: While the patient is on Coumadin, which reduces the risk of pulmonary embolism, the possibility cannot be entirely ruled out, especially if there are any issues with anticoagulation control.
- Cardiac Ischemia: The patient's history of cardiac surgery and current anticoagulation therapy does not exclude the possibility of cardiac ischemia, which can sometimes present with atypical pain.
Rare Diagnoses
- Pancoast Tumor: A rare type of lung cancer that can cause shoulder pain due to invasion of the brachial plexus or shoulder structures. The absence of other symptoms like weight loss or cough makes this less likely.
- Osteonecrosis of the Humeral Head: Although rare, this condition could be considered, especially given the patient's history of steroid use (if any) or significant trauma, neither of which is mentioned in the scenario.