Which lower extremity muscle groups are tested on the MRC-SS?

Which lower extremity muscle groups are tested on the MRC-SS?

• A. Hip abduction; knee flexion; ankle plantarflexion
• B. Hip extension; knee flexion; ankle inversion
• C. Hip flexion; knee extension; ankle DF
• D. Hip internal rotation; knee extension; ankle dorsiflexion

Answer: (C)

The lower-extremity portion of the MRC-SS tests three key movements that reflect the main muscle groups of the leg and are reliably assessable in ICU patients: hip flexion (iliopsoas), knee extension (quadriceps), and ankle dorsiflexion (tibialis anterior). These movements are chosen because they cover proximal to distal strength and provide a representative, practical snapshot of leg function for the MRC sum score. The other movements listed in the distractors aren’t part of the standard lower-extremity testing set for the MRC-SS, so they wouldn’t contribute to this score.

The lower-extremity portion of the MRC-SS tests three key movements that reflect the main muscle groups of the leg and are reliably assessable in ICU patients: hip flexion (iliopsoas), knee extension (quadriceps), and ankle dorsiflexion (tibialis anterior). These movements are chosen because they cover proximal to distal strength and provide a representative, practical snapshot of leg function for the MRC sum score.

The other movements listed in the distractors aren’t part of the standard lower-extremity testing set for the MRC-SS, so they wouldn’t contribute to this score.