A 65-year-old man is brought to the emergency department after being involved in a motor vehicle collision. He lost consciousness briefly on impacting the airbag. Since regaining consciousness, the patient has had numbness, tingling, and marked weakness in both upper extremities but has been able to move his lower extremities normally. Medical history includes osteoarthritis and cervical spondylosis. Blood pressure is 132/74 mm Hg, pulse is 94/min, and respirations are 14/min. Plain x-rays of the cervical spine show no abnormalities except those consistent with mild degenerative arthritis. Which of the following is the most likely diagnosis?

Question

A 65-year-old man is brought to the emergency department after being involved in a motor vehicle collision.  He lost consciousness briefly on impacting the airbag.  Since regaining consciousness, the patient has had numbness, tingling, and marked weakness in both upper extremities but has been able to move his lower extremities normally.  Medical history includes osteoarthritis and cervical spondylosis.  Blood pressure is 132/74 mm Hg, pulse is 94/min, and respirations are 14/min.  Plain x-rays of the cervical spine show no abnormalities except those consistent with mild degenerative arthritis.  Which of the following is the most likely diagnosis?

Quizplus · Accepted Answer

Explanation: 11ec25c8_d59b_6377_bc81_69433eedd5b8_MD0003_00 Hyperextension injury (eg, head impacting an expanded airbag) in elderly patients with preexisting cervical spine degenerative changes (ie, cervical spondylosis) can selectively traumatize the central portion of the spinal cord (SC). The resulting bleeding or concussion of the central cord may result in central cord syndrome (CCS), with clinical findings depending on the size of SC involvement: Small lesions near the central canal disrupt the decussating fibers of the lateral spinothalamic tracts, causing sensory disturbances (eg, numbness, tingling, loss of pain/temperature sensation) in affected dermatomes of the upper extremities. Larger lesions cause additional injury to the central portions of the lateral corticospinal tracts (CSTs). Because upper extremity CST motor fibers are located closer to the central part of the SC than lower extremity motor fibers, CCS is characterized by disproportionate upper extremity weakness. Lower extremity motor function is less affected and may be completely preserved, as in this patient. The sensory and motor disturbances seen in this patient are similar to those seen in cervical syringomyelia, another classic (although slowly progressive) cause of CCS. syringomyelia (Choice A) Anterior spinal artery injury that disrupts blood flow to the anterior two-thirds of the SC can cause anterior cord syndrome. Anterior cord syndrome causes a similar loss of pain/temperature sensation as CCS; however, it typically produces bilateral weakness that is proportionate in the upper and lower extremities because the entire (vs central) CST is affected. anterior cord syndrome (Choice B) Hemisection of the SC results in Brown-Séquard syndrome. It is more commonly caused by penetrating trauma than blunt trauma and would cause an asymmetric (ie, ipsilateral only) motor deficit to both the upper and lower extremities. Brown-Séquard syndrome (Choice D) Cerebral contusion can cause loss of consciousness and focal neurologic deficits. However, contusion severe enough to cause bilateral neurologic deficits (eg, bilateral upper extremity weakness) would likely be accompanied by persistent altered consciousness (due to cerebral edema) and, potentially, seizures. (Choice E) Posterior cord syndrome predominantly affects the dorsal columns, causing loss of vibration/proprioceptive sensation. If weakness is present, it typically also involves the lower extremities. Vitamin B₁₂ deficiency, multiple sclerosis, and tabes dorsalis are more common causes of posterior cord syndrome than trauma. ₁₂ Educational objective: Hyperextension injury, especially in elderly patients with cervical spine degenerative changes (ie, cervical spondylosis), can cause central cord syndrome. This classically causes loss of pain and temperature sensation in the upper extremities and disproportionate upper extremity weakness. References: Acute traumatic central cord syndrome: a comprehensive review. (http://www.ncbi.nlm.nih.gov/pubmed/24613283) Incomplete cord syndromes: clinical and imaging review. (http://www.ncbi.nlm.nih.gov/pubmed/29995620)

A 65-Year-Old Man Is Brought to the Emergency Department After