If a patient has greater motor involvement in the upper extremities than in the lower extremities, which condition do they MOST likely have?

The condition most likely associated with greater motor involvement in the upper extremities than in the lower extremities is central cord syndrome. This syndrome occurs due to damage primarily to the central part of the spinal cord, often caused by cervical spinal cord injuries or conditions that impact the central gray matter and surrounding white matter.

In central cord syndrome, the arm muscles are more affected because the fibers that innervate the upper extremities are located more centrally within the spinal cord. As a result, individuals may experience weakness and loss of function in their upper limbs while the lower limbs may remain relatively stronger and less affected. This characteristic distribution of motor impairment is a hallmark feature of this syndrome.

Other conditions listed have different patterns of sensory and motor impairments. Anterior cord syndrome typically results in greater weakness and loss of function in the lower extremities, cauda equina syndrome primarily affects the lower body and can lead to severe neurological deficits but mostly involves the peripheral nerves, and Brown-Séquard syndrome presents with weakness and sensory loss on one side of the body and is rarely characterized by a greater upper extremity deficit. Each of these conditions has unique clinical presentations distinct from the upper extremity involvement seen in central cord syndrome.