Table 2.

Motor nerve conduction abnormalities suggestive of demyelination

Parameters	Normal value	M±SD (n)	Most abnormal value (%)*	Number of tests	Number of abnormality (%)^	Number of Demyelination (%)^
Median N. DML	< 4 ms	3.9±0.9 (23)	5.5 (137.5%)#	23	9 (39%)	4 (17%)
Ulnar N. DML	< 3 ms	3.0±0.6 (22)	4.1 (136.7%)#	22	10 (45%)	9 (41%)
Peroneal N. DML	< 6 ms	4.3±0.8 (35)	6.1 (101.7%)	38	3 (8%)	0 (0%)
Tibial N. DML	< 7 ms	5.5±1.0 (34)	8.1 (115.7%)	36	4 (11%)	1 (3%)
Median N. CV	> 50 m/s	49.3±6.1 (22)	41(82%)	22	11 (50%)	6 (27%)
Ulnar N. CV	> 50 m/s	52.1±8.0 (23)	42 (84%)	23	4 (17%)	2 (9%)
Ulnar N. CV at elbow	> 50 m/s	48.7±12.6 (20)	30 (60%)#	20	8 (40%)	7 (35%)
Peroneal N. CV	> 40 m/s	40.7±4.6 (20)	25 (62.5%)#	38	14 (29%)	4 (11%)
Peroneal N. CV at knee	> 40 m/s	45.2±9.4 (17)	36 (90%)	20	7 (35%)	0 (0%)
Median F wave latency	< 32 m/s	31.7±3.6 (19)	35.7 (111.6%)	20	9 (45%)	1 (5%)
Ulnar F wave latency	< 32 m/s	30.5±2.0 (14)	33.7 (105.3%)	19	9 (47%)	0 (0%)
Peroneal F wave latency	< 55 m/s	54.6±8.1 (19)	80.5 (146.4%)#	35	22 (63%)	2 (6%)
Tibial F wave latency	< 55 m/s	57.4±10.1 (24)	68.9 (125.3%)	35	26 (74%)	2 (6%)
Median N. CB				23		2 (9%)
Ulnar N. CB				23		4 (17%)
Ulnar N. CB at elbow				20		5 (25%)
Peroneal N. CB				38		12 (32%)
Peroneal N. CB at knee				21		3 (14%)

Note: M±SD (n) showed mean and standard deviation of study values in the number (n) of patients whose responses were recordable.

^*The percentage changes from ULN or LLN were shown in parenthesis.

^#indicates the abnormal values consistent with chronic demyelination.

^{^}The percentage of abnormal test results was shown in the parenthesis.

ULN: upper limit of normal; LLN: lower limit of normal; N.: nerve; DML: distal motor latency; CV: conduction velocity; CB: conduction block.