NIHSS Motor Arm Drift Scoring (Items 5a and 5b)

Question 1

For NIHSS Motor Arm testing, the patient is sitting up. At what angle and for how many seconds must the arm be held to receive a score of 0?

Accepted Answer

90° for 10 seconds

Answer

When the patient is seated, the arm is positioned at 90°. A score of 0 (no drift) requires the patient to hold that position for 10 seconds without any downward movement. If the patient is supine, the angle changes to 45°, but the hold time remains 10 seconds.

Question 2

A patient holds their arm at 90° but it drifts downward before 10 seconds — however, it does not hit the bed or their lap. How is Motor Arm scored?

Accepted Answer

1 — the arm drifts before 10 seconds but does not fall

Answer

A score of 1 is assigned when the arm drifts from the starting position before 10 seconds but does not fall all the way to the bed or the patient's lap. The distinction between score 1 (drift) and score 2 (falls completely) is critical.

Question 3

For a patient who is supine, the Motor Arm test positions the arm at:

Accepted Answer

45° with palm down

Answer

When the patient is supine, the arm is held at 45° rather than 90°. The palm-down position is standard. The angle is adjusted because gravity acts differently on a reclining patient.

Question 4

A patient makes no attempt to raise their arm against gravity and it falls immediately when released. The Motor Arm score is:

Accepted Answer

3 — no effort against gravity

Answer

Score 3 is assigned when the patient makes no effort against gravity — the arm falls immediately with no active resistance. Score 4 (paralysis) is reserved for complete absence of any movement whatsoever, including no twitch or contraction. Score 3 still implies some residual but non-functional effort is absent against gravity.

Question 5

The NIHSS requires the examiner to score Motor Arm for both the left and right arm. If a patient has a pre-existing shoulder injury on the right that limits range of motion, how should the examiner proceed?

Accepted Answer

Score the injured arm as UN (untestable) and note the pre-existing condition

Answer

When a limb cannot be tested due to a pre-existing orthopedic or other non-stroke condition, the item is marked UN (untestable). The examiner must document the reason. This prevents a structural impairment from inflating the stroke severity score.

NIHSS - National Institutes of Health Stroke Scale Practice Test

NIHSS - National Institutes of Health Stroke Scale Practice Test

NIHSS Motor Arm Drift Scoring (Items 5a and 5b)