Most people will eventually deal with back pain from pressure on nerves in the spinal chord. Mechanical decompression is one treatment. Equipment that provides controlled decompression, such as, the DRX9000 from Axiom Worldwide, Tampa (axiomworldwide.com) has been successful with herniated and bulging discs, facet joint pain, and sciatica. Patients reported a mean rate of low-back-pain reduction of 90% and a satisfaction score of 8.55 on a scale of 0 to 10.

Conventional treatments for back pain stretche patients using traction to increase the distance between vertebra. But traction puts a person out of commission for days and in strange uncomfortable positions. Some doctors try to improve on traction using a moving mattress. But most of these tables use plastic slides or composite materials to reduce sliding friction, so they lack precise, controlled movement.

The more recent approach applies momentary tension to a patient's lower body. Axiom says it's more convenient, non-pharmaceutical, and more comfortable than conventional traction. The Axiom design uses steel bearings and shafts under a floating lower mattress. Patients lay flat on a padded, two-part table contoured to keep the knees slightly bent. A floating mattress (on bearings) supports the lower body and moves up to 3.5 in. away from the fixed upper mattress. Patients lay secured only with their arms around stationary padded posts. The lower body, attached to a strap, applies tension. As the body elongates, it reduces pressure on the spine's intervertebral discs.

For precise movement, the lower mattress moves on linear bearings and ground shafts. Each bearing-load plate is also ground. Load plates are thinner on ends more than centers, making the center a fulcrum for self-alignment. And wiper seals on the bearings float so they don't restrict self-alignment.