Root stimulation studies in the evaluation of patients with motor neuron disease

Raynor, Elizabeth M.; Shefner, Jeremy M.; Ross, MA; Logigian, Eric L.; Hinchey, Judith A.

doi:10.1212/wnl.50.6.1907

Cited by 11 publications

(4 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Nevertheless, root stimulation does not disclose proximal conduction block in ALS patients. 46 The F wave is a late response that results from the antidromic activation of one or a small number of motoneurons following peripheral nerve stimulation. 18,28,39 F waves are probably preferentially generated by depolarization at the low-threshold initial segment of large neurons with subsequent invasion of the soma; most antidromic impulses are blocked in the axon hillock of the motoneurons.…”

Section: Discussionmentioning

confidence: 99%

Nerve conduction studies in amyotrophic lateral sclerosis

2000

View full text Add to dashboard Cite

Section: Discussionmentioning

confidence: 99%

Nerve conduction studies in amyotrophic lateral sclerosis

2000

View full text Add to dashboard Cite

“…Root stimulation is particularly difficult, and it requires well-defined normal values for comparison. 117 Although the conduction block may appear at any level, the median nerve in the forearm is a common site rarely susceptible to other disorders. The best evidence of multifocal motor conduction block is a localized region of CMAP amplitude drop or slowing over a few centimeters, demonstrated by "inching" or near-nerve needle stimulation.…”

Section: Motor Unit Number Estimates (Munes)mentioning

confidence: 99%

Electrodiagnostic studies in amyotrophic lateral sclerosis and other motor neuron disorders

Daube

2000

Muscle Nerve

130

View full text Add to dashboard Cite

The clinical electrodiagnostic medicine (EDX) consultant asked to assess patients with suspected amyotrophic lateral sclerosis (ALS) has a number of responsibilities. Among the most important is to provide a clinical assessment in conjunction with the EDX study. The seriousness of the diagnoses and their enormous personal and economic impact require a high‐quality EDX study based on a thorough knowledge of and experience with motor neuron diseases (MNDs) and related disorders. Clinical evaluation will help determine which of the EDX tools available to the EDX consultant should be applied in individual patients. Although electromyography (EMG) and nerve conduction study are the most valuable, each of the following may be helpful in the assessment of selected patients based on their clinical findings: repetitive nerve stimulation, motor unit number estimate, single‐fiber EMG, somatosensory evoked potential, autonomic function test, and polysomnography. The pertinent literature on these is reviewed in this monograph. The selection and application of these EDX tools depend on a thorough knowledge of the MNDs and related disorders. © 2000 American Association of Electrodiagnostic Medicine. Muscle Nerve 23: 1488–1502, 2000

show abstract

“…It has been suggested that cervical root stimulation, either transcutaneously or by using a needle, be used to quantify CB in proximal segments. 16 18 19 Patients with ALS may have a greater degree of CMAP reduction in the proximal segments than in normal subjects because of abnormal temporal dispersion in fibres undergoing active degeneration. 16 It is therefore important to determine the degree of CMAP reduction that can be found, not only in healthy controls but also in ALS.…”

mentioning

confidence: 99%

Transcutaneous cervical root stimulation in the diagnosis of multifocal motor neuropathy with conduction block

Arunachalam

2003

Journal of Neurology, Neurosurgery & Psychiatry

View full text Add to dashboard Cite

Objectives: To determine if transcutaneous electrical stimulation of the cervical roots can be used to diagnose proximal conduction block (CB) in multifocal motor neuropathy (MMN) and whether it can reliably distinguish MMN from amyotrophic lateral sclerosis (ALS). Methods: Compound muscle action potentials (CMAPs) over the abductor digiti minimi (ADM) were evoked by supramaximal stimulation of the ulnar nerve at the wrist, below elbow, above elbow, axilla, Erb's point, and C8/T1 cervical roots in three groups of patients: 31 patients with ALS, nine patients with MMN, and 31 controls. Supramaximal stimulation at Erb's point and the C8/T1 roots was carried out using a transcutaneous high voltage electrical stimulator. The negative peak amplitude, area, and duration of the CMAP were measured and normalised to that from the wrist. The percentage change in each segment in these parameters was calculated and compared between the different groups. Results: At stimulation sites proximal to the elbow, there were no significant differences in relative CMAP amplitude, area, or duration between controls, ALS patients, and MMN patients with clinically unaffected ulnar nerves. Similarly, the percentage segmental change between adjacent stimulation sites showed no significant differences. In six studies of MMN patients with weakness in ulnar hand muscles, the decrease in CMAP amplitude between the C8/T1 roots and Erb's point exceeded the mean + 2 SD of the control data. Conclusion: Cervical root stimulation can quantify CB in the most proximal segment of the ulnar nerve, a fall in CMAP amplitude if greater than 25%, indicating block, and should be used routinely in the evaluation of patients suspected of having MMN, especially when distal stimulation has proved unhelpful.

show abstract

Root stimulation studies in the evaluation of patients with motor neuron disease

Cited by 11 publications

References 0 publications

Nerve conduction studies in amyotrophic lateral sclerosis

Nerve conduction studies in amyotrophic lateral sclerosis

Electrodiagnostic studies in amyotrophic lateral sclerosis and other motor neuron disorders

Transcutaneous cervical root stimulation in the diagnosis of multifocal motor neuropathy with conduction block

Contact Info

Product

Resources

About