In reflex grading, what does a grade of 4+ indicate?

• A. Very brisk, hyperactive, often with clonus
• B. Normal
• C. Diminished
• D. Absent

Answer: (A)

Reflex grading uses a 0-4+ scale to describe how strongly a tendon reflex responds. A 4+ response is very brisk and hyperactive, usually with clonus. This pattern points to upper motor neuron involvement, where loss of inhibitory control over the reflex arc makes the muscle contraction exaggerated. Clonus—the rhythmic, repeated contractions after a stretch—often accompanies a 4+ reflex and reinforces the sign of UMN disturbance. By contrast, normal reflexes are 2+, diminished reflexes are 1+, and absent reflexes are 0. So 4+ best indicates markedly brisk reflexes with possible clonus.