Lumbar traction – alone, or in combination with physical therapy – has been employed for decades as a therapeutic measure in treating back pain. Numerous studies have shown that the procedure stretches muscles and ligaments, increases intervertebral space, and enlarges the foramina and apophyseal joints, but the effects of traction on herniated lumbar discs and the surrounding intervertebral areas have been difficult to study in “real time” with magnetic resonance imaging (MR) because traditional traction devices contain metal, which disrupts the magnets in MR machines.
A 2012 study 1 used a nonmagnetic traction device to study 48 patients—13 men and 35 women— with lumbar disc herniation. The purpose of the study was to determine if the effects of traction on herniated disc patients could be visualized as they were occurring.
Subjects in the study had all been previously diagnosed with lumbar disc herniations and were treated using 30 kg of sustained traction before MR and at 10 minute intervals for a half-hour during lumbar spine imaging. The axial and sagittal images were later reviewed to check for any significant changes that occurred during the procedure. Using the lumbar vertebral column elongation and disc reduction ration as measurements, researchers were able to identify quantitative changes caused by the traction procedure.
Applicants who were pregnant or had previously undergone back surgery, had hypertension, severe osteoporosis, cardiac pacemakers, intracranial clips, lumbar instability, disc inflammation or tumors, were excluded from this study.
Real-time effects of continuous traction are clearly visible when using MR imaging on patients. The study subjects demonstrated significant changes in disc shape, reductions within the openings of intervertebral discs and of herniated disc volumes, as well as widening of the facet joints and separation of the discs and their connected nerve roots, post-traction. The mean lumbar vertebral column length also increased in correspondence with the amount of time a patient underwent traction. The ability to visualize the effects of traction during real-time procedures could be a helpful treatment tool.