A Presumed Rotator Cuff Tear Found to Be a C5 Palsy: A Case Report

Case Diagnosis: 70-year-old with an acute left C5 palsy.

Case Description or Program Description: Patient presents to clinic with new onset left shoulder weakness. The weekend prior he was helping family lift heavy objects and started noticing pain in his left shoulder blade and lower back. A few days later when he attempted to do bicep curls during PT, he had difficulty completing the task with left arm due to weakness. Patient denies any neck pain, numbness in arm, or weakness in distal left upper extremity. On physical exam, he had difficulty abducting and forward flexing his left shoulder. On MMT, deltoid was 2/5 and bicep was 4+/5.

Setting: Academic Musculoskeletal and Sports Medicine Clinic

Assessment/Results: MRI of his left shoulder showed low grade articular sided tearing of the supraspinatus, infraspinatus and subscapularis at the footplate which would not explain the severity of his weakness. Therefore, an MRI cervical spine was ordered which demonstrated multilevel advanced degenerative changes of the cervical spine superimposed upon a developmentally narrow cervical spinal canal with severe spinal canal stenosis at C5-C6 and C6-C7 as well as severe neural foraminal stenoses at C4-C5. Patient was referred to neurosurgical services urgently for possible surgical intervention.

Discussion (relevance): In the setting of injury, isolated shoulder weakness is often attributed to full thickness/complete rotator cuff tears rather than an acute C5 palsy. C5 Palsy is a common complication of spinal decompression but rare to see secondary to cervical stenosis and neuroforaminal stenosis prior to surgery. Although the two have similar clinical findings, the work up and treatments vary significantly. With C5 Palsy due to neuroforaminal stenosis, appropriate neurosurgical intervention is needed.

Conclusions: It is important to keep a broad differential diagnosis for patients presenting with acute shoulder weakness in order for timely intervention to be pursued.