Understanding F-Waves and Spinal Cord Injury in IVDE
When a dog experiences a severe intervertebral disc extrusion (IVDE), one of the most important questions owners and veterinarians face is prognosis — specifically, the likelihood that a dog will regain the ability to walk. Veterinary neurologists use a variety of tools to help assess spinal cord injury, one of which is a specialized electrical test known as an F-wave study.
This page provides a plain-language overview of what F-waves are, why they matter in IVDE, and how ongoing research may help refine prognosis and rehabilitation planning in the future. The information below is based on research shared by veterinary neurologist Dr. Go Togawa.
This page provides a plain-language overview of what F-waves are, why they matter in IVDE, and how ongoing research may help refine prognosis and rehabilitation planning in the future. The information below is based on research shared by veterinary neurologist Dr. Go Togawa.
Dr. Go Togawa on F-Wave Research
“F-waves are small electrical signals that can be recorded from a dog’s foot muscles and are influenced by the spinal cord. By evaluating F-waves, we can indirectly assess how severely the spinal cord is affected after an intervertebral disc extrusion (IVDE).
Although IVDE generally has a good prognosis, in severe cases where dogs are paralyzed and have lost sensation below the site of injury, the chance of regaining the ability to walk after surgery is only about 50–60%.
In our previous work, we found that F-wave patterns after surgery differ between dogs that go on to regain walking ability and those that do not. We are now studying whether these differences can also be detected before surgery, which may eventually help guide prognosis and rehabilitation in individual dogs at the time they first present to the hospital for IVDE.”
“F-waves are small electrical signals that can be recorded from a dog’s foot muscles and are influenced by the spinal cord. By evaluating F-waves, we can indirectly assess how severely the spinal cord is affected after an intervertebral disc extrusion (IVDE).
Although IVDE generally has a good prognosis, in severe cases where dogs are paralyzed and have lost sensation below the site of injury, the chance of regaining the ability to walk after surgery is only about 50–60%.
In our previous work, we found that F-wave patterns after surgery differ between dogs that go on to regain walking ability and those that do not. We are now studying whether these differences can also be detected before surgery, which may eventually help guide prognosis and rehabilitation in individual dogs at the time they first present to the hospital for IVDE.”
F-Wave Examples and Related Research
Dr. Togawa has shared example figures illustrating how F-wave recordings can differ between dogs that regain the ability to walk after IVDE and those that do not. In the figures provided, recording (A) represents a dog that recovered ambulation, while recording (B) represents a dog that remained paralyzed.
He has also shared a peer-reviewed publication from his prior research that closely relates to this work. While the earlier study focused on post-operative data, current research is examining whether similar F-wave patterns can be identified before surgery, which may help guide prognosis and rehabilitation planning at the time a dog first presents for care.
Dr. Togawa has shared example figures illustrating how F-wave recordings can differ between dogs that regain the ability to walk after IVDE and those that do not. In the figures provided, recording (A) represents a dog that recovered ambulation, while recording (B) represents a dog that remained paralyzed.
He has also shared a peer-reviewed publication from his prior research that closely relates to this work. While the earlier study focused on post-operative data, current research is examining whether similar F-wave patterns can be identified before surgery, which may help guide prognosis and rehabilitation planning at the time a dog first presents for care.
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Example F-wave recordings provided by Dr. Go Togawa. Figure (A) shows a recording from a dog that regained walking ability after intervertebral disc extrusion (IVDE), while figure (B) shows a recording from a dog that remained paralyzed.
These examples illustrate how differences in F-wave patterns may reflect the severity of spinal cord injury and help inform prognosis and rehabilitation planning. |
About the Researcher
Dr. Go Togawa, DVM, MS, PhD, DACVIM (Neurology), is an Assistant Professor of Neurology and Neurosurgery at the Virginia–Maryland College of Veterinary Medicine (Virginia Tech). His research focuses on spinal cord injury and electrophysiologic techniques, including the use of F-wave analysis to better understand prognosis and recovery following intervertebral disc extrusion.
Dr. Go Togawa, DVM, MS, PhD, DACVIM (Neurology), is an Assistant Professor of Neurology and Neurosurgery at the Virginia–Maryland College of Veterinary Medicine (Virginia Tech). His research focuses on spinal cord injury and electrophysiologic techniques, including the use of F-wave analysis to better understand prognosis and recovery following intervertebral disc extrusion.
