Jitter evaluation in denervation and reinnervation in 32 cases of chronic radiculopathy

Autor(es)

Kouyoumdjian, Joao Aris ^[1] ; Ronchi, Luis Guilherme ^[2] ; de Faria, Felipe Oliveira ^[2]

Afiliação do(s) autor(es)

^[1] Fac Estadual Med Sao Jose do Rio Preto FAMERP, Lab Invest Neuromuscular LIN, Neurol, BR-15090000 Sao Jose Do Rio Preto, SP - Brazil

^[2] Fac Estadual Med Sao Jose do Rio Preto FAMERP, Neuromuscular Dis & Eletrectromyog, BR-15090000 Sao Jose Do Rio Preto, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: CLINICAL NEUROPHYSIOLOGY PRACTICE; v. 5, p. 165-172, 2020.
• Citações Web of Science: 0

Resumo

Objective: To measure the jitter parameters in muscles with denervation/reinnervation in 32 chronic radiculopathy cases. Methods: Measurements were done in chronic denervated muscles by voluntary and electrical activation using a concentric needle electrode. Results: Mean jitter was abnormal in 87.5% (mean 49.2 ms) and 81.25% (mean 36.8 ms), for voluntary and electrical activation. In muscles with fibrillation potentials (FPs), the mean jitter was abnormal in all cases, and impulse blocking was frequent (53.4-92.3%). In muscles without FPs, the mean jitter was abnormal in 78.9% for voluntary activation and 68.4% for electrical activation. No correlation was found between jitter and motor unit action potential amplitude. Conclusion: The muscles with FPs were associated with the immature spread of acetylcholine receptors (AChRs) throughout the muscle membrane. Conversely, the neuromuscular junctions (NMJs) assemble may be repressed by the already reinnervated muscles. For those, higher jitter may be due to the persistence of atrophic fibers expressing neonatal myosin heavy chain (MHC) and immaturity of NMJ composting instead of the overspread of immature AChRs. Significance: Jitter measurement must be avoided in chronic denervated muscles, regardless of FPs' presence. The activity of reinnervated muscle could maintain neonatal MHC and repress new NMJs development. (C) 2020 International Federation of Clinical Neurophysiology. Published by Elsevier B.V. (AU)

• Processo FAPESP: 17/13262-4 - Eletromiografia de fibra única: estudo da microfisiologia de junção neuromuscular durante reinervação
• Beneficiário: João Aris Kouyoumdjian
• Modalidade de apoio: Auxílio à Pesquisa - Regular