Table.
Serial Nerve Conduction Studies.
| Nerve conduction (Right) |
The first examination | After 2 years | After 5 years | After 14 years | After 18 years | After 19 years | Controls* mean (SD) |
|---|---|---|---|---|---|---|---|
| Median nerve | |||||||
| MCV (m/s) | 25.0 | 36.0 | 23.0 | 27.0 | 31.0 | 32.0 | 57.6 (3.8) |
| DL (ms) | 9.1 | 9.8 | 7.4 | 8.6 | 6.9 | 7.1 | 3.4 (0.4) |
| Distal CMAP duration (ms)** | 6.7 | 5.6 | 5.1 | 5.5 | 5.7 | 6.3 | 4.7 (0.9) |
| CMAP (mV) | 12.8 | 5.7 | 0.9 | 4.3 | 6.3 | 8.3 | 8.2 (2.9) |
| FO (%) | 38.0 | ND | ND | ND | 43.8 | 43.8 | 67.6 (20.3) |
| F latency | 45.7 | ND | ND | ND | 50.0 | 43.6 | 22.3 (1.9) |
| SCV (m/s) | 16.0 | 19.8 | 56.3 (5.3) | ||||
| SNAP (μV) | 1.8 | NE | NE | NE | NE | 1.5 | 28.0 (11.5) |
| Ulnar nerve | |||||||
| MCV (m/s) | 26.0 | 30.0 | 29.0 | 32.0 | 35.0 | 35.0 | 58.0 (4.6) |
| DL (ms) | 7.6 | 6.6 | 6.4 | 6.1 | 5.6 | 5.3 | 2.6 (0.3) |
| Distal CMAP duration (ms)** | 7.0 | 5.9 | 5.2 | 5.7 | 6.1 | 6.7 | 5.1 (0.7) |
| CMAP (mV) | 7.5 | 4.1 | 2.4 | 3.6 | 4.8 | 4.0 | 7.4 (1.8) |
| SCV (m/s) | 21.0 | 22.8 | 54.5 (5.5) | ||||
| SNAP (μV) | NE | NE | NE | NE | 1.0 | 2.0 | 23.8 (10.3) |
| Tibial nerve | |||||||
| MCV (m/s) | 20.0 | 29.0 | 13.0 | 26.0 | 26.0 | 26.0 | 46.0 (3.8) |
| DL (ms) | 17.2 | 13.8 | 7.6 | 15.3 | 11.5 | 7.8 | 4.0 (0.6) |
| CMAP (mV) | 1.0 | 0.6 | 1.1 | 1.7 | 1.1 | 1.0 | 11.8 (3.5) |
| Sural nerve | |||||||
| SCV (m/s) | 19 | 49.2 (4.8) | |||||
| SNAP (μV) | NE | NE | 0.8 | NE | NE | NE | 16.8 (7.8) |
CMAP: compound muscle action potentials, DL: distal latency, MCV: motor nerve conduction velocity, ND: not determined, NE: not elicited, SCV: sensory nerve conduction velocity, SNAP: sensory nerve action potentials
*Control values were based on previously published reports (15, 16).
**Duration from onset to the first crossing of the baseline in CMAP was measured (15).