In the last issue of The American Chiropractor, I focused primarily on the issue of intergrating Whole Body Vibration (WBV) into your daily office procedures. When we, as Doctors of Chiropractic, are recommending a particular therapy to our patients, we want to be certain to understand the physiologic effects of the particular modality and the medical reasoning for using it. We need to be able to explain to our patients why we are recommending the routines we are prescribing and why it is important for them to follow our instructions and recommendations. In this article, I will focus on the neuro-physiology behind the WBV technology. This will explain very clearly why Whole Body Vibration is such a perfect adjunct to the chiropractic practice!
For the sake of the space available for this article, I will keep it simple and in layman’s terms.
As we have all learned in college, an active contraction of a muscle is initiated via efferent nerve fibers. For the sake of dealing with circumstances and situations where a rapid succession of contractions is necessary, nature has equipped us humans with a rather ingenious design. This design helps to prevent rapid fatigue in a muscle, When consciously contracting a muscle, only approximately 40 percent of the muscle fibers in any given skeletal muscle are being utilized at any given time. When these fibers fatigue, the brain shifts the contractions to another 40 percent of musle fibers within the same muscle. This pattern repeats itself throughout the muscle, as long as needed, thus delaying rapid fatigue.
Enter WBV: When a muscle is being isometrically loaded, approximately 40 percent of the fibers are being contracted. If, in addition to this contraction, the muscle is being subjected to a vibrational load within a specific Hertz range, the Tonic Vibration Reflex is being triggered. This reflex causes a sustained contraction of the whole muscle subjected to vibration. This Tonic Vibration Reflex is evoked by placing a vibrator—in the case of WBV, it is typically a platform set in motion by an electrical motor with an eccentric load on its shaft—in line with the isometrically loaded muscles and, therefore, activates the muscle’s tendon and muscle spindles. In order to activate receptors of the skin, tendons and, most importantly, muscle spindles, vibrations in the range of 20-100 Hz are needed. Muscle spindle excitation and subsequent discharges of afferent fibers are then sent to the spinal cord through the afferent nerve fiber’s tracts, where they activate monosynaptic and polysynaptic reflex arcs, causing the corresponding muscle to contract. Thus, the residual 60 percent of the muscle is being contracted, resulting in much more rapid fatigue of the subjected muscle! This may be due to either “central fatigue” of the neural drive or even “peripheral fatigue,” which is described as an insufficient energy supply within the muscle for the increased workload and demand. This explanation founds the very basis for the effectiveness of WBV for the purpose of exercise and rehabilitation.
Since WBV activates muscles in a static, isometric position without necessitating joint ROM, it allows the chiropractic doctor to initiate exercise protocols much earlier in the treatment cycle. An injured joint and the surrounding musculature can be exercised quite early in the treatment cycle. This enhances local circulation and lymphatic drainage and accelerates tissue repair. I have found that our patients progress significantly faster through the acute phase of injuries once the WBV protocols are implemented. In the acute phase, we have the patient start by stabilizing their position by holding on to the WBV unit. Once the patient has shown improvement, we slowly progress them to doing their exercises without holding on to the unit. This necessitates them to utilize all the collateral musculature of the originally injured joint and further engages proprioceptive response and integration.
Thus, WBV offers a fast, easy, simple, yet safe, way to shift the patient from passive to active care, gets them feeling better and motivates them to participate in their own recovery.
We usually have the patient start by using the equipment three times a week and see rapid improvement. Once the patient has demonstrated improvement in their re-evaluation, they are then progressed from pain relief care to rehabilitation care. This is accompanied by the patient doing joint ROM under load while on the WBV unit. Starting with small ROM, they are ultimately progressed to doing their full ROM rehabilitation protocols while being subjected to WBV on the units.
The final stage of rehabilitation can be called the neurologic integration phase. Here, our patients perform full ROM exercises, with the added challenge of performing these exercises while doing balance positions. Based on the findings of several Russian researchers, performing full ROM exercises while experiencing WBV enhances postural automatisms and muscle memory. Also, reviewing the research done by Prof. Dr. Vladamir Janda, it is of utmost importance not to conclude the rehabilitation phase for any injury right after subsiding of the acute pain phase, but to finish the rehabilitation with neural integration techniques. As seen above, WBV can be a phenomenal tool for this purpose.
As a value-added benefit, when using WBV for injury treatment, many of our patients also encounter improved hand/eye coordination in their sports. In my humble opinion, this can only be explained through the repeated challenge to the vestibular system by the WBV while firing the afferent and efferent nerves necessary to perform a particular motion.
The utilization of WBV during training by virtually all professional teams in football, baseball, basketball and hockey promises great hope for our patients. If it works for training those athletes and helps them get better faster, I believe it ought to be good enough for our patients! Every chiropractor involved with treating patients with musculo-skeletal issues should consider implementing this modality in their office!
Dr. Christian H. Reichardt is a 1983 graduate of National College of Chiropractic. He may be reached at 1-310-829-0453, [email protected] or visit www.Golf-Health.com.