Patients walk into our office every week asking the same question in slightly different ways. Does the table really pull my spine apart? Is it just fancy traction? How can stretching fix a disc problem? Fair questions, and the answers are more interesting than most people expect. As a Draper chiropractor who uses decompression daily for disc herniations, sciatica, and chronic low back pain, I want to walk through what’s actually happening inside your spine when you’re on the table, because understanding the mechanism tends to make patients more confident in the process and better at following through with care.
What a spinal disc is doing under normal conditions
Picture a jelly donut sitting between two vertebrae. The outer ring, called the annulus fibrosus, is tough and fibrous. The inner core, the nucleus pulposus, is gel-like and mostly water. Every time you stand, sit, lift, or bend forward, that disc gets compressed. Pressure inside a healthy lumbar disc while standing runs around 100 psi. Sitting hunched forward can push it past 140 psi. Over years of repeated loading, the disc loses water, the annulus develops small tears, and the nucleus can push outward or rupture through, which is when nerve pain shows up.
The disc has no direct blood supply. It receives nutrients through a process called imbibition, essentially a sponge effect, drawing in fluid and nutrients when pressure drops and releasing waste when pressure rises. Damaged discs lose this pumping ability, which is part of why they heal slowly on their own.
The mechanical difference between traction and decompression
Old-school traction pulls in a straight line with constant force. The body responds the way it would to any sustained pull: muscles guard, the spine tightens, and intradiscal pressure barely changes. You feel stretched without much therapeutic effect happening at the disc itself.
Decompression tables are computer-controlled and work in cycles. The pull builds slowly, holds, releases partially, then pulls again, often for 15 to 20 minutes per session. The cyclic pattern fatigues the protective muscle guarding response, which is the key. Once those paraspinal muscles stop fighting the pull, the targeted vertebrae actually separate, and that’s when something measurable happens at the disc.
Negative pressure and what it accomplishes
Research using pressure transducers inside discs has shown that proper decompression can drop intradiscal pressure into negative numbers, sometimes as low as negative 150 to negative 200 mmHg. That negative pressure does three things worth caring about.
It creates a vacuum effect that can draw herniated or bulging disc material back toward the center, away from the nerve root it’s been irritating. It pulls water, oxygen, and nutrients into the disc through that imbibition process I mentioned earlier, supporting the slow repair of damaged tissue. And it relieves the mechanical pressure on the nerve, which is often what’s driving the sharp leg pain, numbness, or weakness patients show up with.
Why the angle and the patient matter
Decompression isn’t one-size-fits-all. A disc problem at L5-S1 responds best to a pull angle near 15 degrees, while an issue higher up at L3-L4 needs closer to 10 degrees. Cervical decompression for neck and arm pain uses different equipment and much lighter forces, usually starting around 10 to 12 pounds and building from there.
Patient weight, the location of the disc lesion, muscle tone, and how long the problem has been present all change the protocol. A 200-pound former athlete with a six-week-old herniation needs different settings than a 130-pound office worker with eight years of degenerative changes. This is part of why outcomes vary so much between clinics. The technology only works as well as the clinician using it.
What the research actually shows
Studies on decompression therapy have reported success rates between 70% and 86% for appropriate candidates, with appropriate being the operative word. Patients with contained disc herniations, radiculopathy, degenerative disc disease, and facet syndrome tend to respond well. Patients with severe osteoporosis, spinal fractures, certain surgical hardware, or pregnancy are not candidates.
MRI follow-ups in several studies have shown actual reductions in disc herniation size after a full course of decompression, which is meaningful because it suggests structural change, not just symptom masking.
What a session actually feels like
You lie on a padded table. A harness fits around your pelvis and another secures your upper body. The computer-controlled motor begins the cyclic pull, which feels like a slow, comfortable stretch through the lower back. Most patients describe it as relaxing. A typical course runs 15 to 25 sessions over six to eight weeks, with frequency tapering as the disc stabilizes.
Putting the science to work for your spine
Decompression therapy isn’t magic and it isn’t a stretch in the conventional sense. It’s a controlled mechanical process that changes pressure inside an injured disc long enough for the body to do its repair work. If you’ve been dealing with disc-related pain and want to know whether you’re a candidate, a Draper Chiropractor at Draper Spinal Care can review your imaging, examine your spine, and tell you honestly whether decompression makes sense for your case. Reach out when you’re ready to talk through the details.
