clTrac Traction Device

Physicians have used traction for spinal disorders since antiquity, including Glisson in the 17th century and Erasmus Darwin at the close of the 18th — by which point the approach had proven its worth. In 1789, Jean André Venel introduced an extension bed designed to treat scoliosis through traction and countertraction in the horizontal position.

In 1810, the German physician Schreger developed a spinal traction bed that, remarkably, was more sophisticated than many 20th-century models that followed it. By the early 20th century, spinal traction's main use had shifted toward correcting deformities after spinal injuries — horizontal or diagonal traction with carefully controlled weights replaced the older method of vertical suspension using the patient's own body weight.

In practice, traction is used most often for the cervical spine, while spinal traction as a form of manipulation is now also common for the lumbar and thoracic spine. Today's traction devices are used together with dedicated traction treatment tables, generally connected via a universal attachment plate — and, for safety, always paired with a patient interrupt button.

How it works

Traction lengthens the spine and flattens the lordotic curve, enlarging the space between vertebrae. That lengthening is believed to be central to the therapy's effect, and can remain present for up to two hours after a session ends. The reduced excitation of intrafusal muscle fibers has a relaxing effect and lowers muscle tension, with both continuous and intermittent protocols showing this response.

Enlarging the intervertebral space also produces a drop in intradiscal pressure. In a bulging disc, this creates a suction effect that draws the nucleus pulposus back toward the centre of the disc, while a disc or capsule entrapment can be lifted, letting the joint surfaces glide past one another again. The improved fluid balance within the disc can persist beyond the treatment itself.

What the clinical evidence shows

For non-specific neck pain and cervical radiculopathy, traction is typically used alongside other therapies rather than on its own, and meta-analyses of clinical studies point to meaningful effects on short- and mid-term pain. Reported adverse events are limited and broadly in line with other manual therapies, supporting cervical traction's safety profile.

For lumbar traction, current clinical thinking is that most people with low back pain or lumbar radiculopathy/sciatica respond well to a physical-therapy program that combines traction, exercise and manual therapy. If back pain hasn't eased after four to six weeks, it's generally recommended to intensify the physical-therapy program.

Peripheral traction — applied to the limbs — is well established for tensioning a displaced bone or joint, such as a dislocated shoulder, helping guide it back into position and hold it stable. Traction on an arm or leg is also a recognised technique for broken bones, often used as pre-operative preparation, and skeletal traction can help realign unstable fractures. In rehabilitation, limb traction is used to keep a muscle group stretched and reduce spasm.

Taken together, traction can offer pain reduction and functional improvement for patients with non-specific neck pain, cervical or lumbar radiculopathy, nerve root compression, spinal stenosis, degenerative cervical myelopathy, sciatica, herniated discs (lumbar, lumbosacral or cervical) and spondylosis.