Chiropractic Corner
We get numerous questions regarding the use of inversion tables. Inversion tables are a good tool to stretch the lumbar spine and help reduce the axial load on the discs and nerves of the lumbar spine. It is important to note that these types of tables are designed for the low back and do not affect or benefit the midback (thoracic spine) or neck (cervical spine). The idea and technology for this type of table dates back to Greek antiquity with Hippocrates and Galen. Currently, there are many manufactures and models with a large range of options and prices.
How does it work?
The discs in the lumbar spine are under constant pressure. This pressure is measured in mmHG, just like a weather barometer. While standing, the pressure within the lumbar disc is significant – the gravitational load from your upper body plus the muscular tension within your spine measures 100mmHg. Even when you are lying down, the muscular tension keeping your spine together measures 75mmHg. Inversion tables use gravity and the weight of your upper body to help reduce this pressure and stretch the tight ligaments and muscles of the lumbar spine. Inversion tables have been shown to reduce this pressure in the lumbar disc by about half (40mmHg) when compared to lying down. Computerized decompression tables are able to pull at greater forces and with repeated programmed rest periods to actually achieve negative pressures within the disc (-160mmHg). Many brands of decompression tables can target the cervical spine as well. We often recommend inversion tables for home use after a patient has undergone a series of decompression treatments in our office. Decompression tables will be discussed in the next Chiropractic Corner.
How often, what angle, what duration?
The number one recommendation for all home based treatment and therapy is: DO NOT TRY AND PUSH THOUGH THE PAIN. If it hurts, stop. More is not always better. Ideally, inversion treatment would be done on a daily basis while the symptoms persist. Each session should consist of 5-7 two minute intervals with at least a minute rest between intervals to avoid muscular guarding and spasm. Let’s do some math, geometry and physics. Depending on your body shape, about 60% – 70% of your total weight is in your upper body above your lumbar spine. That means if you weigh 150 lbs, about 100 pounds of your weight is in your upper body. If you are using an inversion table at a 45 degree angle, half of the weight of your upper body (50 lbs) is now being axially distracted from your lumbar spine, hips, and knees. At 60 degrees, this increases to about three quarters of your upper body weight (75 lbs), which is now half of your total body weight. This is typically enough unloading of the lumbar spine to have some therapeutic effects. 50% of body weight is where we typically start our computerized lumbar decompression therapy. It is important to note that decompression tables only distract the thoracolumbar spine, while with inversion tables, distraction is spread throughout to the lumbar spine, hips, and knees.
What to watch out for?
Inversion tables create distraction on the knees and hips, which can be aggravating and possibly damaging for patients with knee and hip pathology. Those with conditions such as labrum tears, meniscus tears, and joint replacement should get clearance from their physician before starting inversion therapy. Inversion tables also increase pressure within the cranium and eyes and cause the heart to work harder to move blood. Patients with head, eye, or heart pathology should seek medical clearance. I encourage you to have someone within shouting distance, or a phone in your pocket, just in case you have difficulty getting off of the table or get stuck in an inverted position. Ease into each session gradually and take short breaks every few minutes. Remember that you are stretching muscles in a direction that have they haven’t been stretched before. One of the most common side effects of inversion therapy is muscle spasm. There are large variations between different manufacture models in quality and price. The best have a large amount of foam padding, especially for the lower leg and shin area. Remember, you are putting a significant amount of pressure on your shin and ankles. These areas of your body have minimal padding and will get sore with prolonged pressure. -Dr. Chance Moore, D.C. Back to Arizona Pain Monthly
