Which grade is associated with clonus during reflex testing?

Which grade is associated with clonus during reflex testing?

• A. Grade 0
• B. Grade 1
• C. Grade 2
• D. Grade 4

Answer: (D)

Clonus signals a very brisk reflex and is typically noted when the reflex grading reaches the highest level. In the common deep tendon reflex scale, responses range from 0 (no reflex) to 4+ (very brisk, with clonus). The presence of clonus—rhythmic, repetitive contractions after a tendon tap—indicates an exaggerated stretch reflex due to upper motor neuron involvement, and this is categorized as the highest grade. So, when clonus is observed during reflex testing, the grade documented is the top one, reflecting a brisk reflex with clonus.

Clonus signals a very brisk reflex and is typically noted when the reflex grading reaches the highest level. In the common deep tendon reflex scale, responses range from 0 (no reflex) to 4+ (very brisk, with clonus). The presence of clonus—rhythmic, repetitive contractions after a tendon tap—indicates an exaggerated stretch reflex due to upper motor neuron involvement, and this is categorized as the highest grade. So, when clonus is observed during reflex testing, the grade documented is the top one, reflecting a brisk reflex with clonus.