Pulsed Electromagnetic Field Therapy for Accelerating Peripheral Nerve Regeneration and Preserving Neuromuscular Junctions
Abstract
The most common injuries sustained by soldiers in Iraq and Afghanistan result from blast and shrapnel wounds caused by improvised explosive devices (IEDs). These injuries are associated with a high probability of nerve damage to the arms and legs. Although IED injuries typically are survivable, injured Soldiers face a lengthy rehabilitation course and the possibility of long-term functional impairments. Current extremity reconstruction strategies for major injuries address bone, muscle, vascular, and skin restoration. However, in order to achieve functionality, the nerves supplying the injured muscles also must be restored if they are cut. The degree of recovery experienced after a nerve injury depends on how well the nerve is sewn together, how far the nerve has to grow back to reach the muscle to which it was connected, and how long the muscle remains without an intact nerve supply. Surgical advances have improved how well the nerves can be repaired. How fast the nerve grows back from the site of the injury/repair to the muscle it innervates is important because the longer the muscle remains without having the nerve connected to it, the less likely it is that the muscle will work again when the nerve finally does grow back. Two approaches to improve the chances for optimal recovery can be followed: (1) efforts can be made to increase the speed with which the nerve grows back and (2) attempts can be made to preserve the ability of the muscle to function properly once the nerve grows back. To date, little success has been attained in pursuing either approach. Sometimes special surgeries can use other nerves near by the muscle to re-connect the muscle to the brain, but this means that some other muscle has to sacrifice its nervous connections. These surgeries are also difficult, and only a few surgeons can perform them. Other investigators have tried to use drug injections into the muscles that have lost nervous innervation, but these have not been very successful. This project will use a different approach to try and speed up re-growth of the injured nerve as well as preserve the ability of the denervated muscle to be re-animated once the injured nerve has grown back. This will employ a medical device that has been used to speed up bone healing called Pulsed Electromagnetic Field (PEMF) therapy. It was discovered that if two coils of wire were placed on opposite sides of a fracture in the distal forearm and an electrical current was passed through them with specific wave patterns, the fracture would heal faster and, in many cases, would heal even if it had not healed previously. Scientists have studied these kinds of devices in experiments with animals and found that they can increase the rate at which nerves grow after injury. They also discovered that they can improve recovery of the muscle after it has been denervated and then had the nerve reconnected. The proposed study will examine how well this PEMF system might work in a rat when a nerve in the leg has been injured and then repaired. The speed at which the nerve grows back will be studied, and how well the leg functions after the nerve heals will be studied and compared to rats with identical injuries but that have not received the PEMF treatment. In a separate study, the nerve connecting muscles to the spinal cord will be cut but not repaired. The rats will receive PEMF therapy and the muscles will be studied over time to see if the biological connections that have the potential to rejoin with an injured nerve remain intact. Usually, these connections disappear over time, but it is anticipated that the PEMF will keep the connections intact. If these experiments are successful, they may indicate a new method for improving treatment of injured Soldiers as well as civilians who sustain injuries to the nerves of the arms and legs. The treatment already is approved for treating fractures that do not heal in patients. Therefore, if effective
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Oct 29, 2018
- Source ID
- W81XWH1710513
Entities
People
- Thomas Smith
Organizations
- United States Army
- Wake Forest University