A 65-year-old man comes to the office due to right upper extremity pain after falling on his right outstretched hand 2 days ago. The patient has mild abrasions over his wrist and elbow with full range of motion and no tenderness over these joints. He has severe pain when he tries to lift his arm above shoulder level or when he pulls or pushes with his right arm. He has been unable to sleep the last 2 nights due to pain and is unable to lie on the affected side. The patient has a 40-pack-year smoking history. His father died of multiple myeloma. Vital signs are normal. Examination shows limited active abduction and external rotation of the humerus; however, passive motion is comparable to the contralateral side. Palpation of the right shoulder, collarbone, and neck reveal no step-off deformities or point tenderness. Radial pulse, extremity sensation, muscle tone, and bulk are normal. Which of the following would most likely confirm the diagnosis in this patient?

Question

A 65-year-old man comes to the office due to right upper extremity pain after falling on his right outstretched hand 2 days ago.  The patient has mild abrasions over his wrist and elbow with full range of motion and no tenderness over these joints.  He has severe pain when he tries to lift his arm above shoulder level or when he pulls or pushes with his right arm.  He has been unable to sleep the last 2 nights due to pain and is unable to lie on the affected side.  The patient has a 40-pack-year smoking history.  His father died of multiple myeloma.  Vital signs are normal.  Examination shows limited active abduction and external rotation of the humerus; however, passive motion is comparable to the contralateral side.  Palpation of the right shoulder, collarbone, and neck reveal no step-off deformities or point tenderness.  Radial pulse, extremity sensation, muscle tone, and bulk are normal.  Which of the following would most likely confirm the diagnosis in this patient?

Quizplus · Accepted Answer

11ec25c8_d2ed_a821_bc81_b55937252e9b_MD0003_00 This patient has post-traumatic shoulder pain with limited active abduction, most likely due to a rotator cuff tear. Rotator cuff tears are most common in patients age >40, often after a fall on an outstretched arm. Patients typically have pain at the lateral shoulder that is worsened with raising the arm overhead or with external rotation and abduction. Examination shows the drop arm sign (inability to smoothly control shoulder adduction) and weakness with external rotation (passive range of motion is normal). Rotator cuff tendinopathy (tendinitis) may also present with pain on abduction, but tendinopathy without tear does not cause weakness. X-ray of the shoulder in a rotator cuff tear is often performed as an initial study to rule out fracture; in large, chronic tears it may demonstrate migration of the humeral head, but it has low sensitivity for confirming the diagnosis of an acute tear (Choice F). MRI can visualize the soft tissues around the humeral head and can accurately diagnose a rotator cuff tear. Treatment of an acute tear usually involves surgery, with best results if performed within 6 weeks of the injury. rotator cuff tear (Choice A) Bone scans are most often used to diagnose infectious (eg, osteomyelitis) or metastatic disease. However, these conditions would not usually present with acute post-traumatic pain and decreased range of motion. (Choice B) With this patient's extensive smoking history, lung cancer involving the brachial plexus (Pancoast syndrome) could cause shoulder pain. However, this would typically present with radicular pain radiating to the wrist, atrophy of the muscles, and additional compressive symptoms (eg, edema). (Choice C) CT of the shoulder is effective in diagnosing fractures and other disorders involving cortical bone but is less sensitive than MRI for visualization of tendons and other soft tissue structures. (Choice D) MRI of the spine would identify the cause of cervical radiculopathy. This condition usually results from disc herniation (or osteophytes) and presents with arm weakness, paresthesias, and neck pain. Educational objective: Rotator cuff tears occur most commonly in patients age >40, often after a fall on an outstretched arm. These injuries are characterized by pain and weakness with abduction and external rotation of the humerus. MRI can confirm the diagnosis. References: The diagnostic accuracy of MRI for the detection of partial- and full-thickness rotator cuff tears in adults. (http://www.ncbi.nlm.nih.gov/pubmed/22260933)

A 65-Year-Old Man Comes to the Office Due to Right