Table 3.
Muscle group | Nerve root | Strength | Description |
---|---|---|---|
Iliopsoasa | L1, L2, L3 | 0 | Absence of any muscle activation |
1 | Able to flex hip against gravity (allow knee to passively flex, chair for balance) | ||
2 | Able to flex hip against gravity, and maintain (allow knee to passively flex, chair for balance) | ||
3 | Difficult to assess; can consider full strength if flex hip against gravity and maintain without difficulty | ||
Quadricepsb | L2, L3, L4 | 0 | Absence of any muscle activation |
1 | Able to perform a single leg raise from chair with support | ||
2 | Able to perform a single leg raise from chair without support, moderate difficulty | ||
3 | Difficult to assess; can consider full strength if able to perform a single leg raise from a chair without support or perceived difficulty | ||
Tibialis anterior | L4 | 0 | Absence of any muscle activation |
1 | Able to raise onto heels, unable to maintain | ||
2 | Able to raise onto heels and maintain this position for 10 seconds | ||
3 | Difficult to assess; can consider full strength if able to raise onto heels and perform lateral walks for 10 paces | ||
Gastrocnemius-soleus complex | S1 | 0 | Absence of any muscle activation |
1 | Able to raise onto toes, unable to maintain | ||
2 | Able to raise onto toes (raise heels) and perform 10 heel raises, with some difficulty | ||
3 | Difficult to assess; can consider full strength if able to perform 10 repetitions of heel raises without perceived difficulty |
a May be performed in seated position if patient unable to balance.
b If unable to perform single leg raise, may perform knee extension and attempt to maintain against gravity