Establishing Normal Values for F-Wave Latencies in Diagnosing Peripheral Neuropathies for the Pediatric Population

We present a unique technique applying F-wave latencies to assist in the diagnosis of peripheral neuropathy within the pediatric age group.

We calculated an F-wave estimated deviance adjusted for limb length measurements, distal motor conduction velocity, and distal motor latencies. We compared the F-wave estimated deviance from the normal subjects with those with peripheral neuropathy (both axonal and demyelinating) to establish diagnostic accuracy in pediatric patients.

The normal range for the F-wave estimated deviance in the upper limb was -1 to +6 ms and in the lower limb was -8 to +5 ms. When compared with 82 subjects with peripheral neuropathy, there was a significant difference between the normal subjects and those with neuropathy (P values between 0.002 and 0.0005 for each of the individual nerves tested).

The F-wave estimated deviance is independent of age and can be accurately applied to the electrodiagnostic testing of pediatric patients with suspected neuropathy.