If a patient experiences enlargement of the normally rudimentary central canal of the spinal cord in the MID cervical region, which, if any, muscular functions would become abnormal first?: (A) Finger flexion, (B) Elbow flexion, (C) Shoulder abduction, (D) Truncal extension
Answer is C. Ans. C. Shoulder abductionMotor neurons controlling axial muscles are positioned most medially in the ventral horn area. An enlarged central canal would impinge on that pool of motor neurons first.