Advances in sensibility evaluation.

What is needed is a quick, practical, cost-effective measurement instrument that can be depended upon to provide clear and reliable information regarding normal versus abnormal function. In the future, objective measurements will enable review of patient peripheral nerve injuries and neuropathies in treatment populations and will allow direct correlation of peripheral nerve status with treatment. Important points can be summarized as follows: (1) With newer technology, improved testing instruments are possible that can both expand understanding of clinical conditions and in the end simplify testing through stimulus control with errors eliminated. (2) With understanding of the requirements for controlled stimuli, clinicians can assess the objectivity of any current and future test instrument and/or can use an instrument in as repeatable a method as possible within its identified limitations. (3) Many current test instruments have been helpful in providing useful clinical information, but better instrument control is needed to improve the quality of information and to develop minimum recommendations for testing. (4) Newer instruments that have undergone instrument reliability testing should be compared with existing instruments that have met the requirements for reliability in a valid protocol before they can be said to have greater or less value in detecting clinical status. (5) Data regarding reliability studies should be available and should not be taken at face value alone; just because a manufacturer states reliability studies have been done, or a paper concludes an instrument is reliable, does not mean the instrument or testing protocol meets the requirements for scientific design. (6) A test instrument needs to be as sensitive as the system it is trying to measure; most currently available instruments apply stimuli too gross to sensitively detect abnormal function, or to sensitively detect early changes (improvement or worsening) in clinical status. (7) For the first time there exists the possibility of computer-controlled instruments for evaluating long-standing physiologic concepts, and there will soon be an explosion of newer information under which all instruments should be considered. (8) The Semmes-Weinstein monofilaments are one of the most objective instruments (if not the most) and are available for clinical testing either for detailed mapping or for screening extent and degree of nerve pathology; combination with electroneuromyography is recommended in determining level of involvement.