1. Andary, M.T., So, Y. T., Wilkins, D.E., Williams, F.H., “Literature review of the usefulness of nerve conduction studies and electromyography for the evaluation of patients with carpal tunnel syndrome.” Muscle & Nerve, 1993; 16:1392-1414.
Verbose summary of studies utilizing NCS for diagnosis. Fit for electrodiagnosticians only.
2. Ashworth, N.L., Marshall, S.C., Satkunam, L.E., “The effect of temperature on nerve conduction parameters in carpal tunnel syndrome.” Muscle & Nerve, 1998; 21: 1089-1091.
Shows effects of cold temperature on decreasing nerve conduction velocity and means of correcting the error. Small error is of debatable significance. This is a controversial topic (see Fine reference below).
3. Baba, M., Ozaki, I., Watahiki, Y., Kudo, M., Takebe, K., and Matsunaga, M. “Focal conduction delay at the carpal tunnel and the cubital fossa in diabetic polyneuropathy.” Neurophysiol, 1987; 27:119-123.
Confirms that even with diabetic neuropathy localized entrapment can be superimposed. Ties in with the work of A.L. Dellon.
4. Buchthal, F., Rosenfalck, A., Trojaborg, W., “Electrophysiological findings in entrapment of the median nerve at wrist and elbow.” J of Neurology, Neurosurgery, and Psychiatry, 1974; 37; 340-360.
5. Corwin, H.M., Kasden, M.L., “Electrodiagnostic reports of median neuropathy at the wrist.” J of Hand Surgery, 1998; 23A: 55-57.
This study of limited value study which is pointing out the high frequency of incompletely or suboptimally performed nerve conduction study and the limitation that this is anticipated to have on the diagnosis and treatment of people with upper extremity complaint. Based on a review of 100 consecutive reports, the patients presenting to their practice in comparison to the guidelines of the American Academy of Neurology or the American Association of Electrodiagnostic Medicine and the American Academy of Physical Medicine and Rehabilitation.
6. Donofrio, P.D. and Albers, J.W. “AAEM minimonograph #34: Polyneuropathy: Classification by nerve conduction studies and electromyography.” Dept of Neurology Wake Forest Univer. Winston-Salem North Carolina, 1990; 34.
7. Fine, E.J., Wongjirad, C. “The fallacy of temperature correction in carpal tunnel syndrome.” Muscle & Nerve, 1985; 628.
Controversial topic. No value to non-electrodiagnosticians.
8. Goodwill, C.J., “Carpal tunnel syndrome: Long term follow up showing relationship of latency measurements to response to treatment.” Annuals Phys Med Rehab 1998: 1: 12-21.
He reviewed nerve conduction studies of 98 patients, pre and post op carpal tunnel release. Of note, results of non-operative treatment in this series were similar to others report in that local steroid injection only resulted in permanent relief in 11% of the patients. Night splints gave similar long-term results to local steroids, with only 58% achieving any temporary benefit, compared with 74% achieving temporary benefit with corticosteroid injection. He confirmed that results of surgery gave relief of symptoms permanently regardless of the degree of conduction delay and that all patients operated on successfully showed an improved or normal nerve conduction study latency and persistent relief of symptoms. No decrease in latency was felt to be an indication for re-exploration of the carpal tunnel, as exemplified by 6 patients in this series. Likewise they concluded with their results that night splints had no advantage over injections of corticosteroid, thus they were recommending corticosteroid as a conservative means if necessary, contending that local corticosteroids should only be used while awaiting operation in case of muscle weakness, persistent sensory loss, or pain radiating to the shoulder. He used a motor latency of 8 msec or more as a cutoff for certain indication that non-operative treatment would fail. (This old study had patients with very marked prolongation of latencies, while most patients presenting nowadays have shorter latencies because they present at an earlier stage of the disease.
* This poor reasoning will result in unnecessary re operation. Some latencies increase mildly after decompression due to excessive re myelination. Thus latency alone is not grounds for surgery.
9. Grant, K.A., Congieton, J.J., Koppa, R.J., Lessard, C.S., Huchingson, R.D., “Use of motor nerve conduction testing and vibration sensitivity testing as screening tools for carpal tunnel syndrome in industry.” JHS, 1992: 17: A: 71-76
10. Hallet, M., “Electrodiagnostic approaches to the diagnosis of entrapment neuropathies.” Neurol Clin, 1985; 3:3:531-541.
Supplements the report by Shamir of Pease, Phys Med and Rehab Clinics of North Am, and that of Robinson, JAAOS 2000
11. Jackson, D.A., Clifford, J.C., “Electrodiagnosis of mild carpal tunnel syndrome.” Arch Phys Med & Rehabil, 1989; 70:199-204.
12. Johnson, E.W., Kukla, R.D., Wongsam, P.E., Piedmont, A., “Sensory latencies to the ring finger: normal values and relation to carpal tunnel syndrome.” Arch Phys Med & Rehabil, 1981; 62:206-208.
Must read for hand specialist and neurologists.
13. Kimura, J. “The carpal tunnel syndrome: Localization of conduction abnormalities within the distal segment of the median nerve.” Brain, 1979; 102: 619-635.
Classic. Must read for doctors.
14. Kirschberg, G.J., Fillingim, R., Davis, V., Hogg, F., “Carpal tunnel syndrome: Classical clinical symptoms and electrodiagnostic studies in poultry workers with hand, wrist, and forearm pain.” Southern Medical Journal, 1994; 328-331.
A report on 112 consecutive charts of patients referred to their neurology clinic to be evaluated for carpal tunnel syndrome. He noted that only 17% of the 112 had classic symptoms and a positive electrodiagnostic study compatible with CTS. They therefore concluded that the incidence of CTS in patients doing repetitive motion might have been over-estimated. They recommended very strict clinic and electrodiagnostic criteria be used in order to make the correct diagnosis. There are definite limitations on the way the authors perform the study. They used an atypical, incomplete technique for the nerve conduction studies. Though they used exceptionally good quality nerve conduction equipment, the criteria they were using for calling the study positive was antiquated and too rigid, therefore incompatible with that in general use throughout the Western world. There was sampling biased in the form of a neurology clinic, to which only a certain percentage of the plant would be going anyway. They point out that CTS claims had surpassed back injuries for the first time in 1990.
15. MacLean, I.C., Cho, D.S., “Carpal tunnel syndrome: A comparison of distal sensory latencies of median and radial nerves.” Muscle & Nerve, 1981; 444.
Discusses median-superficial radial sensory latency difference to the thumb. They feel this is the most sensitive. In my experience (Dr. Ichtertz) this is a useful adjunct, but no more sensitive than median-ulnar nerve sensory latency difference.
16. Redmond, M.D. and Rivner, M.H. “False positive Electrodiagnostic tests in carpal tunnel syndrome.” Muscle & Nerve, 1988; 11: 511-517.
Worthless. Overly pessimistic view in possible false positive rather than being concerned with false negative results.
17. Robinson, L.R., “Role of neurophysiologic evaluation in diagnosis.” Journal AAOS, 2000; 8:190-1999.
Very nice synopsis of use and interpretation of nerve conduction studies.
18. Robinson, L.R., Micklesen, P.J., Wang, L., “Strategies for analyzing nerve conduction data: Superiority of a summary index over single tests.” Muscle & Nerve, 1998; 21:1166-1171.
Very complicated. Not for the novice, but the experienced electrodiagnostician.
19. Salerno, D.F., Franzblau, A., Werner, R.A., Bromberg, M.B., Armstrong, T.J., Albers, J.W., “Median and ulnar nerve conduction studies among workers: normative values.” Muscle & Nerve, 1998; 999-1000.
One among many marginal and largely unimportant studies from this group. Not worth reading.
20. Seror, P. “Nerve conduction studies after treatment for carpal tunnel syndrome” JHS 1992; 17B: 641-645.
Shows the predictable improvement in NCS (decreased latency and increased conduction velocity after CTR).
21. Silver, M.A., Gelberman, R.H., Gellman, H., Rhoades, C.E. “Carpal tunnel syndrome: Associated abnormalities in ulnar nerve function and the effect of carpal tunnel release on these abnormalities.” JHS, 1985; 10A.
With MRI showing the change in ulnar tunnel shape occurring with CTR this explains the elimination of ulnar dysesthesias with a single operation despite entrapment of two nerves.
22. Smith, J., “Radial nerve conduction in patients with carpal tunnel sydrome.” Appl Neurophysiol, 1981; 44:363-367.
23. Steinberg, D.R., Gelberman, R.H., Rydevik, B., and Lundborg, G. “The utility of portable nerve conduction testing for patients with carpal tunnel syndrome: A prospective clinical study.” JHS, 1992; 17A: 77-81.
Points out the usefulness of comparison of median and superficial radial nerve conduction to the thumb in detection of CTS. Poor study with poor patient selection used to justify a very insensitive portable NCS device. Not recommended.