Neurophysiological classification and sensitivity in 500 carpal tunnel syndrome hands.
OBJECTIVE
To evaluate the following points about carpal tunnel syndrome (CTS): 1) characterization of a wide population; 2) sensitivity of electrodiagnostic tests, and particularly the contribution of disto-proximal ratio test; 3) validity of a neurophysiological classification developed by us.


METHODS
Prospective study in 500 hands with CTS symptoms. Neurophysiological "standard" tests were always performed: sensory nerve conduction velocity (SNCV) first- and third digit-wrist and distal motor latency (DML). In "standard negative" hands disto-proximal ratio technique (R) was performed. Neurophysiological classification: Extreme CTS (absence of median motor, sensory responses), Severe (absence of sensory response, abnormal DML), Moderate (abnormal SNCV, abnormal DML), Mild (abnormal SNCV, normal DML), Minimal (abnormal R or other segmental/comparative test, normal standard tests).


RESULTS
Sensibility of standard tests: 77%. R increased the diagnostic yield by 20%. CTS classification appeared reliable with significant differences between groups.


CONCLUSIONS
R is a useful test, the classification may be useful in clinical/therapeutical decisions.
Padua
L
L
Department of Neurology, Università Cattolica del Sacro Cuore, Rome, Italy.
LoMonaco
M
M
Gregori
B
B
Valente
E M
EM
Padua
R
R
Tonali
P
P
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002349:Carpal Tunnel Syndrome / Q000145:classification / Q000175:diagnosis / Q000503:physiopathology*; D004568:Electrodiagnosis; D005260:Female; D006225:Hand / Q000294:innervation*; D006801:Humans; D008297:Male; D008475:Median Nerve / Q000503:physiopathology; D008875:Middle Aged; D009046:Motor Neurons / Q000502:physiology; D009431:Neural Conduction / Q000502:physiology; D011930:Reaction Time / Q000502:physiology; D011984:Sensory Receptor Cells / Q000502:physiology; D009435:Synaptic Transmission / Q000502:physiology*