Thursday, April 22, 2010

CSM revisited: Head trauma types: Blunt Force, Acceleration/Deceleration, and Blast

The Federal section of the APTA works to provide support for those who deliver quality physical therapy in Federal Medical facilities. As one can imagine, these PTs spend much of their time working with war veterans, many who have had a traumatic brain injury along with other injuries. The course at CSM was listed as “Balance at a high level: Vestibular training for the Amputee.” While much of the vestibular training is commonly used, the reason why these men with amputations require vestibular training is unusual. Kim Gottshall, PT, PhD, ATC and retired Colonel, US Army Reserves presented this training on this topic to about 150 PTs and PTAs at CSM. The information focused mostly on mild traumatic brain injuries and common associated symptoms.
The fact is blast type head injuries are fairly new. With new technology in body armor, the thorax is protected saving the life of the soldier, and helmets provide some protection from blunt force trauma and/or coup-countercoup (acceleration/deceleration) type head injuries. However, the blast type head injury, created by the shock-wave of the blast is different, and very little study has been done on this topic. The study of the other two types has been building for two to three decades, and there may be little to correlate with blast injuries.
In addition to body armor technology, the other factors that lead to this “signature” injury of the current two wars (Iraq and Afghanistan) is that much of the warfare is urban, as well as that improvised explosive devices are the weapons of choice for the opposition. The shock wave effect creates a sheering injury in the vestibular end organs, as well as a significant release of excitatory neurotransmitters. The result is oxidative cellular stress and direct stimulation of apoptotic pathways. Part of the presentation, then, is multiple site involvement. This means that there may be peripheral and central damage and resulting symptoms. Also common are cognitive difficulty and hearing loss or tinnitus. “Dizziness” is often reported as well, but the type and quality of the dizziness associated with blast injuries is still not characterized.
With lack of clinical research in this area, the current suggestions are to recognize that the neurological exam may result in findings that do not fall into a known pattern and to be as thorough as possible. In addition, quantifiable testing is helpful, such as using computerized dynamic posturography and VOR equipment if available. There are four suggested groups: 1. Post traumatic positional vertigo. 2. Post traumatic exertional dizziness. 3. Post traumatic migraine associated dizziness. 4. Post traumatic spatial disorientation. Blast head injuries also tend to have more cognitive difficulty and more hearing loss along with these different combinations of diagnoses.
Rehabilitation should be focused on the results of the examination. Video was shown and those with amputations were able to complete even the highest demands of rehabilitation with the prosthesis. Dr. Gottshall reported a study that she recently completed. While the exact study methods and procedures were not outlined, several notes were made about the subjects. The main observation was that cognitive rehabilitation seemed to correlate positively with vestibular rehabilitation. In addition, patients perceived improvement before functional gains were made. Finally, there is a temporal component to vestibular rehabilitation.
I look forward to seeing the published studies to come on the nature and sequelae of blast head injuries. For more information about the Federal section of the APTA: A full text article on what is known about
blast head injuries can be found at:

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