Back In Place

By Paul Hoffmann, MD, and John Kelly, MPT

Lately, decompression therapy has been receiving a fair share of attention. And for good reason, as the incidences of back and neck pains are still occurring with alarming frequency.

Simply put, spinal decompression is traction applied in constant or intermittent phases to isolate mechanical impairment in the neck or back. Barring spinal instability, traction is a gentle approach to treat common spinal dysfunctions, to address nonfused, post-surgical discomfort or manage failed back syndrome.

At our center, traction plays an important role to treat spinal conditions, and successful intervention depends on accurate communication between a physician and physical therapist. In addition, a proper diagnosis, the administration of medications and injections, if warranted, and a physical therapy program are key components to maximize patient outcomes. This article will address the approach physicians and therapists should take with respect to spinal derangement, while incorporating traction or decompression therapy into a treatment regime.

Promoting Recovery

Traction promotes recovery, while bed rest avoids compression. Spinal discs are essentially devoid of circulation, except for the outermost layers of the annulus, and depend on diffusion for nutrition. Nuclear substrate acts as an irritant and its reduction can lead to fibroblastic activity, collagen deposition and annular healing.

Traditional diagnoses of disc pathology, such as prolapse, herniation and stenosis, respond to spinal traction. Traction for a small nuclear displacement is the treatment of choice. In more severe conditions, traction combined with manual treatment and pharmacology is more likely to lead to resolution.

During traction there’s a separation of the vertebrae and an unweighting of soft tissue. By decreasing intervertebral pressure a vacuum is created, which reduces the protrusion. Backward bending is thought to lessen posterior annular strain and reduce extruded nuclear material. However, forces acting posterior don’t correspond to a reduction in nuclear material.

Although narrowed in the lower lumbar area, tensioning the posterior longitudinal ligament through traction offers support to posterior structures and facilitates anterior migration of the protrusion. Traction forces also offer relief from tissues under stress from impingement in the presence of an osteophyte, pain without range limitations and gradual onset of lower back or radicular pain.

Range restrictions from myofascial tension or facet arthropathy interrupt healthy lymphatic diffusion and hydration can cause a degenerative process. Mobilization should be part of a treatment approach to thoroughly address degenerative disc disease. Facet syndromes respond to distraction created by spinal traction. Unweighting the joint and soft tissue with relief from stress and strain can reduce pain, lessen inflammation and stimulate healing.

Improving the Method

Manual therapists have commonly used belts and strapping to apply traction to the cervical and lumbar spine. Original mechanical traction devices applied force to a fixed patient and modifications were made to a standard treatment plinth.

Lumbar treatment tension was considered 30 kg to 80 kg, given a high friction coefficient so patients couldn’t easily slide over the upholstery. The advent of pneumatic tension heads and friction-free tables have improved this situation significantly, reducing tensions to 20 kg for women and 50 kg for men.

Historically, an accepted value of 50 percent body weight up to patient tolerance was considered appropriate. However, the accuracy of electronic tension heads and anecdotal treatment feedback suggest even less tension is necessary for a proper therapeutic dose.

Traction equipment is advantageous to the practitioner in energy conservation and body mechanics. Modern electronic traction is more efficient in tension production and patient positioning–a marked improvement over previous devices. Former traction devices included constant or intermittent settings without regard to relaxation of contractile tissue.

Clinicians commonly use blood pressure cuffs or electromygraphic feedback for erector spinae relaxation. Now, individual timer settings allow progressive steps to full traction, while accommodating muscle guarding and soft tissue restriction. As a result, this allows traction forces to fall on joints and discs. Step-down timer settings gradually return the patient to a resting state and discourage reflexive muscle spasms.

This also permits gentle, end-range oscillation, setting pulls with brief hold times and grossly reproducing manual therapy techniques. New devices offer the flexibility to select pull speeds that depend on a condition’s reactivity. Previously, equipment only pulled at a set speed.

Mechanical traction accomplishes the goal of centralizing and reducing the frequency and intensity of pain. Mobilizations should precede traction interventions. But should traction be applied when all other interventions have failed? Innovations in traction equipment provide a more comfortable environment for joint and myofascial mobilization, and these techniques facilitate skilled intervention to allow patients to make quicker transitions into the gym for stabilization exercises.

However, as is the case with many treatment interventions, it’s still a work in progress and additional research must continue to establish guidelines to optimize outcomes.


Browder, D.A., Erhard, R.E., & Piva, S.R. (2004). Intermittent cervical traction and thoracic manipulation for management of mild cervical compressive myelopathy attributed to cervical herniated disc: A case series.Journal of Orthopedic Sports Physical Therapy, 34(11), 701-712.

Cyriax, P.J. (1993). Orthopedic Medicine (2nd ed.) (pp.221-223). Butterworth-Heinemann: Philadelphia.

Falkenberg, J., Podein, R.J., Pardo, X., & Iaizzo, P.A. (2001). Surface EMG activity of the back musculature during axial spinal unloading using an LTX 3000 lumbar rehabilitation system. Electromyography and Clinical Neurophysiology, 41(7), 419-427.

Maitland, G.D. (1986). Vertebral manipulation (5th ed.) (pp. 303-308). Butterworth-Heinemann.

Paul Hoffman, MD, is the medical director at Siskin Hospital for Physical Rehabilitation in Chattanooga, Tenn.He’s also affiliated with Chattanooga Rehabilitation Associates and the Siskin Spine and Rehabilitation Clinic. John Kelly, MPT, is an outpatient therapist at Siskin Hospital for Physical Rehabilitation in Chattanooga.