Record over the dorsal web space between digits IV and V and stimulate just proximal and inferior to the ulnar styloid.
01 · Placement
With the hand pronated, place G1 on the dorsoulnar hand in the web space between the fourth and fifth metacarpals, where the two bones converge in a V.
Dorsal ulnar cutaneous study · p.11 ↗Place G2 3–4 cm distal to G1 over the dorsal little finger, continuing along the same line toward digit V.
Distance · 3–4 cm distal to G1
Dorsal ulnar cutaneous study · p.11 ↗Stimulate 8 cm proximal to G1, just proximal and slightly inferior to the ulnar styloid; keep the hand pronated and orient the cathode distally.
Distance · 8 cm from G1
Dorsal ulnar cutaneous study · p.11 ↗Place the ground on the dorsoulnar wrist between the stimulation site and the D4–D5 web-space recording electrodes.
Table 2 · p.373 ↗02 · Reference values
| Measure | Reference limit | Basis |
|---|---|---|
| SNAP amplitude | ≥8 µV | AANEM educational reference |
| Conduction velocity | ≥50 m/s | 8 cm antidromic technique |
| Distal peak latency | ≤2.5 ms | 8 cm antidromic technique |
03 · Technique
Primary evidence
Dorsal ulnar cutaneous sensory values for an 8 cm antidromic D4–D5 web-space technique.