Record over tibialis anterior and stimulate below the fibular head and at the lateral popliteal fossa.
01 · Placement
Place G1 over the tibialis anterior motor point in the proximal-to-middle anterolateral calf and adjust for an initially negative CMAP deflection.
Common fibular motor study to tibialis anterior · p.32 ↗Place G2 distally over the tibialis anterior tendon at the anterior ankle, completely off the muscle belly.
Distance · Distal to G1 and completely off the muscle belly
Common fibular motor study to tibialis anterior · p.32 ↗Stimulate the common fibular nerve on the lateral calf one to two fingerbreadths below the fibular head, using the laboratory's matched 5–10 cm distal segment.
Distance · 5–10 cm proximal to G1; use the laboratory's matched method
Common fibular motor study to tibialis anterior · p.32 ↗Stimulate in the lateral popliteal fossa adjacent to the lateral hamstring tendon, 10–12 cm proximal to the below-head site.
Distance · 10–12 cm proximal to S1
Common fibular motor study to tibialis anterior · p.32 ↗Place the ground on the anterolateral calf between the tibialis anterior recording electrodes and fibular-head stimulation sites.
Table 2 · p.373 ↗02 · Reference values
| Measure | Reference limit | Basis |
|---|---|---|
| Distal CMAP amplitude | ≥3.0 mV | AANEM educational reference |
| Conduction velocity | ≥44 m/s | Method-matched segment |
| Distal motor latency | ≤6.7 ms | 5–10 cm distal distance |
03 · Technique
Primary evidence
Common fibular motor reference values recorded from tibialis anterior.