Case Studies supporting PEMF benefits for Nerve
Chronic Electrical Nerve Stimulation as a Therapeutic Intervention for Peripheral Nerve Repair
When a peripheral nerve is injured after either trauma or a neurodegenerative disease, motor function and sensory perception are impaired. Repair strategies aim both at reconstructing the damaged nerve and in promoting regeneration to enhance target reinnervation and functional recovery. Advanced surgical procedures can enable efficient repair, but restoration of function remains challenging. Among various factors influencing nerve regeneration, electrical stimulation is often cited as a potential therapeutic approach to nerve repair, engaging regenerative transcriptional programs. In this report, we review both reported effects on axonal growth and functional outcomes of electrical stimulation on peripheral nerve repair and the techniques for chronic nerve stimulation, highlighting the challenges and opportunities of such repair strategies.
Effects of Electromagnetic Field (PEMF) Exposure at Different Frequency and Duration on the Peripheral Nerve Regeneration: in Vitro and in Vivo Study
Purpose: The purpose was to clarify the influence of frequency and exposure time of PEMF on the peripheral nerve regeneration.
Materials and methods: Immortalized rat Schwann cells (iSCs) (1×102 /well) were exposed at 4 different conditions in 1mT (50Hz 1Hr/day, 50Hz 12Hr/day, 150Hz 1Hr/day and 150Hz 12Hr/day). Cell proliferation, mRNA expression of S100 and brainderived neurotrophic factor (BDNF) were analyzed. SpragueDawley rats (200–250g) were divided into 6 groups (n D 10 each): control, sham, 50Hz 1Hr/day, 50Hz 12Hr/day, 150Hz 1Hr/day and 150Hz 12Hr/day. Mental nerve was crush injured and exposed at 4 different conditions in 1mT (50Hz 1Hr/day, 50Hz 12Hr/day, 150Hz 1Hr/day and 150Hz 12Hr/day). Nerve regeneration was evaluated with functional test, histomorphometry and retrograde labeling of trigeminal ganglion.
Results: iSCs proliferation with 50Hz, 1Hr/day was increased from 4th to 7th day; mRNA expression of S100 and BDNF was significantly increased at the same condition from 1st week to 3rd week (p<.05, vs. control); Difference score was increased at the 2nd and 3rd week, and Gap score was increased at the 3rd under 50Hz 1Hr PEMF compared with control while other conditions showed no statistical meaning. Axon counts and retrograde labeled neurons were significantly increased under PEMF of 4 different conditions compared with control. Although there was no statistical difference, 50 Hz, 1Hr PEMF showed highest regeneration ability than other conditions.
Conclusion: PEMF enhanced peripheral nerve regeneration, and that it may be due to cell proliferation and increase in BDNF and S100 gene expression.
Electrical Stimulation: A Novel Tool for Tissue Engineering
New advances in tissue engineering are being made through the application of different types of electrical stimuli to influence cell proliferation and differentiation. Developments made in the last decade have allowed us to improve the structure and functionality of tissue-engineered products through the use of growth factors, hormones, drugs, physical stimuli, bioreactor use, and two-dimensional (2-D) and three-dimensional (3-D) artificial extracellular matrices (with various material properties and topography). Another potential type of stimulus is electricity, which is important in the physiology and development of the majority of all human tissues. Despite its great potential, its role in tissue regeneration and its ability to influence cell migration, orientation, proliferation, and differentiation has rarely been considered in tissue engineering. This review highlights the importance of endogenous electrical stimulation, gathering the current knowledge on its natural occurrence and role in vivo, discussing the novel methods of delivering this stimulus and examining its cellular and tissue level effects, while evaluating how the technique could benefit the tissue engineering discipline in the future.
Electrical Stimulation to Promote Peripheral Nerve Regeneration
Peripheral nerve injury afflicts individuals from all walks of life. Despite the peripheral nervous system’s intrinsic ability to regenerate, many patients experience incomplete functional recovery. Surgical repair aims to expedite this recovery process in the most thorough manner possible. However, full recovery is still rarely seen especially when nerve injury is compounded with polytrauma where surgical repair is delayed. Pharmaceutical strategies supplementary to nerve microsurgery have been investigated but surgery remains the only viable option. Brief low-frequency electrical stimulation of the proximal nerve stump after primary repair has been widely investigated. This article aims to review the currently known biological basis for the regenerative effects of acute brief low-frequency electrical stimulation on axonal regeneration and outline the recent clinical applications of the electrical stimulation protocol to demonstrate the significant translational potential of this modality for repairing peripheral nerve injuries. The review concludes with a discussion of emerging new advancements in this exciting area of research. The current literature indicates the imminent clinical applicability of acute brief low-frequency electrical stimulation after surgical repair to effectively promote axonal regeneration as the stimulation has yielded promising evidence to maximize functional recovery in diverse types of peripheral nerve injuries.
Electrically stimulating nerve and muscle to enhance regeneration and reinnervation following peripheral nerve injury
Recovery following peripheral nerve injuries is often incomplete. The gold standard treatment is surgical nerve repair performed immediately or shortly after injury. To date, there are no additional treatments that are used to enhance functional recovery. In this paper we outline two emerging applications of electrical stimulation to enhance nerve regeneration and functional recovery. The first is brief electrical nerve stimulation performed at the time of nerve repair that is used to accelerate nerve outgrowth across the injury site. The second is daily electrical muscle stimulation that reduces muscle atrophy and also accelerates muscle reinnervation.
Pulsed Electromagnetic Therapy Improves Functional Recovery in Children with Erb's Palsy
Purpose: The purpose of the study was to evaluate the influence of pulsed electromagnetic field therapy (PEMF) on functional recovery in Erb's palsy.
Design: Randomized controlled trial.
Subjects: Thirty patients were included (16 males and 14 females) with age ranged from six to twelve months (mean=7.3±1.1).
Methods: Children were divided randomly into two equal groups, control and experimental. Both groups received a physiotherapy training program; in addition, the study group received PEMF for 30 min. Treatment regimen was once a day, three times/week for three months. Measurements of the affected upper extremity (length, girth and width, muscle strength and range of motion) were carried out before and after treatment.
Results: There was significant improvement in most of the measured test parameters in the study group compared to those of the control group.
Conclusion: : Pulsed electromagnetic therapy, in conjunction with conventional therapy program, was effective in improving functional recovery in children with Erb's palsy.
Case Study Reference Source:
1. Chronic Electrical Nerve Stimulation as a Therapeutic Intervention for Peripheral Nerve Repair
(Authors: Miyuki Sakuma, Ivan R Minev, Sandra Gribi, Bhagat Singh, Clifford J Woolf and Stéphanie P Lacour)
2. Effects of Electromagnetic Field (PEMF) Exposure at Different Frequency and Duration on the Peripheral Nerve Regeneration: in Vitro and in Vivo Study
(Authors: WeiHong Hei, SooHwan Byun, JongSik Kim, Soochan Kim, YoungKwon Seo, JooCheol Park, SoungMin Kim, Jeong Won Jahng, JongHo Lee)
3. Electrical Stimulation: A Novel Tool for Tissue Engineering
(Authors: "Richard Balint, B.Sc., M.Sc.", "Nigel J. Cassidy, B.Sc. (Hons), Ph.D." and "Sarah H. Cartmell, B.Eng. (Hons), Ph.D.")
4. Electrical Stimulation to Promote Peripheral Nerve Regeneration
(Authors: "Michael P. Willand, PhD", "May-Anh Nguyen", "Gregory H. Borschel, MD" and "Tessa Gordon, PhD")
5. Electrically stimulating nerve and muscle to enhance regeneration and reinnervation following peripheral nerve injury
(Authors: Michael P. Willand, Gregory H Borschel, and Tessa Gordon)
6. Pulsed Electromagnetic Therapy Improves Functional Recovery in Children with Erb's Palsy
(Authors: Reda Sarhan, Enas Elsayed, Eman Samir Fayez)