MRC Sum Score (ICU-Acquired Weakness)

MRC sum score (Kleyweg 1991): manual-muscle-test grades 0-5 across six bilateral muscle groups (shoulder, elbow, wrist, hip, knee, ankle); the 0-60 sum < 48 defines ICU-acquired weakness.

Open the calculator → Runs in your browser. Data leaves only if you deliberately send a problem report from the interactive tool.

Example

Shoulder abduction, left
4
Shoulder abduction, right
4
Elbow flexion, left
4
Elbow flexion, right
4
Wrist extension, left
4
Wrist extension, right
4
Hip flexion, left
4
Hip flexion, right
4
Knee extension, left
4
Knee extension, right
4
The other 2 values
Ankle dorsiflexion, left
4
Ankle dorsiflexion, right
4

Result: MRC sum 48/60: at or above 48 -- ICU-acquired weakness is not met (< 48 threshold).

The tool opens with these values already filled in. Replace them with your own.

What the result means

Scale
six movements graded bilaterally (12 muscle groups), each 0-5 on the MRC scale, for a sum of 0-60.
Threshold
a sum below 48 defines ICU-acquired weakness; below 36 is severe.

What you enter

  • Shoulder abduction, left (0-5)
  • Shoulder abduction, right (0-5)
  • Elbow flexion, left (0-5)
  • Elbow flexion, right (0-5)
  • Wrist extension, left (0-5)
  • Wrist extension, right (0-5)
  • Hip flexion, left (0-5)
  • Hip flexion, right (0-5)
  • Knee extension, left (0-5)
  • Knee extension, right (0-5)
The other 2 fields
  • Ankle dorsiflexion, left (0-5)
  • Ankle dorsiflexion, right (0-5)
How this is calculated

De Jonghe B, Sharshar T, Lefaucheur JP, et al. Paresis acquired in the intensive care unit: a prospective multicenter study. JAMA. 2002;288(22):2859-2867. Read the source ↗

A reference and educational tool. Not medical, legal, or financial advice, and not a substitute for clinician judgment.

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Built by Clay Good. Source on GitHub.