Hi Erika! I hope I can help with this! The motor level is defined as “the lowest key muscle function that has a grade of at least 3, providing the key muscle functions represented by segments above that level are judged to be intact (graded as a 5).” In this example, the patient’s elbow flexors (C5) were graded as 2/5, so this cannot be the motor level. There is no formal motor test for C4 on the ISNCSCI; therefore, we assume the motor level is the same as the next highest level with intact sensation. Sensation is normal at C4, which is why the motor level on the left is presumed to be C4. Let me know if I can provide any more clarification!
Chrissy
