The short version
If you only read one section, make it this one.
Cochrane's 2013 review, the biggest body of evidence, found traction made little or no difference. The DRX9000 study clinics quote most, by Apfel's team in 2010, found large improvements, but it had no comparison group and was sponsored on behalf of the company holding the table's FDA clearance. And herniated discs often shrink without surgery, which flatters any study that doesn't compare against people who skipped the treatment.
Our position, then. Decompression is a reasonable thing to try for pain that behaves like a disc problem, inside a plan that stops when it isn't helping. It's not something we'd tell anyone to prepay because a website printed a percentage.
The study clinics quote most (Apfel, 2010)
Christian Apfel's team published it in BMC Musculoskeletal Disorders in 2010 (volume 11, article 155). It's a retrospective cohort, meaning the researchers looked back at people who'd already been treated: 30 patients, 21 women and 9 men, average age 65, each with 22 DRX9000 sessions over 6 weeks and a CT scan before and after.
The numbers are striking. Average low back pain fell from 6.2 to 1.6 on a 0–10 scale, and disc height rose from 7.5 mm to 8.8 mm. The two changes moved together, with a correlation of r = 0.36.
Now the part the authors wrote themselves. There was no control group, and they pointed out that herniated discs often recover without treatment. The study was also sponsored through NEMA Research on behalf of Axiom Worldwide, the company that held the DRX9000's original FDA clearance.
That correlation deserves a second look, too. An r of 0.36 is modest: it says pain relief and disc height tended to move in the same direction, not that the added height caused the relief.
The review that found no advantage (Cochrane, 2013)
One cohort can't settle a question like this. Pooled randomized trials come much closer.
Wegner and colleagues searched the research through August 2012 and included 32 randomized trials with 2,762 participants. Traction on its own, or added to other treatment, had little or no impact on pain intensity, function, global improvement or return to work. The finding held with or without sciatica, and it covered manual traction as well as the mechanical kind.
They graded the evidence as low to moderate quality. Better trials could still move the picture. But as of September 2026, the review we'd weigh most doesn't point toward decompression, and pretending otherwise would just be marketing.
Harms showed up as well: 7 of the 32 studies reported side effects, namely increased pain, aggravated neurological signs and subsequent surgery. We can't turn that into a per-patient risk for you. It's why real pain on the table at Mecham Chiropractic means stopping to reassess, never pushing through.
An older review got there first
Writing in Pain Practice in 2006, Macario and Pergolizzi reviewed prospective trials published from 1975 to October 2005. Among the randomized trials they examined, 6 of the 7 found no difference with motorized decompression, and they judged its efficacy for chronic discogenic low back pain unproven.
Why both can be true
So which result is right? Possibly both, and the reason is worth a couple of minutes.
Start with who was studied. Apfel's group was 30 people averaging 65 years old, every one of whom had received 22 DRX9000 sessions, looked at after the fact. The Cochrane trials assigned far more people to treatments at random, across different kinds of traction and different kinds of back pain. A treatment can look good in a small group reviewed in hindsight and still show no advantage once chance decides who gets it.
Then there's the bigger issue: herniated discs often shrink with no surgery at all. Wang, Dai, Jiang and Liao pooled 38 studies covering 2,219 patients treated without surgery and published the result in 2020. The pooled regression rate was 63% (95% CI 49–77%).
How much depends on the type of herniation. In earlier research the authors cite, sequestrations regressed 96% of the time, extrusions 70%, protrusions 41% and bulges just 13%.
Put those numbers next to a study without a control group and the trouble is plain. If many herniations shrink regardless, a group measured before and after 6 weeks of almost any care can show less pain and changed discs, and whatever treatment they happened to get takes the credit.
That doesn't mean decompression did nothing for Apfel's patients. It means the study can't tell us, and only randomized comparisons can; the ones we have are the ones Cochrane pooled.
"But decompression isn't traction," the argument goes. That deserves its own answer, and it gets one in traction vs. spinal decompression: a sham-controlled trial of a decompression device found no difference from a fake pull.
(A short detour, because it's related: a scan isn't a verdict either. Brinjikji and colleagues pooled imaging from 3,110 people with no back pain in 2015 and found disc bulges in 30% of 20-year-olds and 84% of 80-year-olds. Back to the studies.)
About success-rate claims on clinic websites
If a decompression website shows you a success percentage, ask one thing first: where did that number come from?
We don't publish one, and it isn't because we're sitting on a flattering figure. We don't know of a single reliable success rate for spinal decompression. The randomized evidence points to little or no difference, and the favorable study described above had no comparison group.
When a clinic does give you a number, these follow-ups sort it out quickly:
- Was it a published study, or the clinic's own patients?
- Did anyone in the study not get decompression?
- What counted as success: less pain, better function, or simply finishing the plan?
- Who paid for the research?
That last one isn't cynical. Apfel's team disclosed its sponsor, which is what honest research does. If a figure is being used to sell a package, slow down. Richard Deyo, professor emeritus at Oregon Health & Science University, told FairWarning in 2020 that the best evidence suggests little advantage from these devices, and the same report put a full DRX9000 course at about $3,500.
Before you sign anything, read what spinal decompression costs in Salt Lake City and whether Utah insurance covers decompression.
Is it a permanent fix?
We can't promise that, and we'd be wary of anyone who does.
There's no reliable evidence we know of on how long relief lasts after a decompression plan ends, so we won't put a timeline on it. What imaging research does tell us is that disc wear is ordinary. In that same Brinjikji review, disc degeneration showed up in 37% of pain-free 20-year-olds and 96% of pain-free 80-year-olds, and the authors concluded many such findings are likely normal aging, unassociated with pain.
So the goal isn't a disc that looks young on an MRI. It's getting back what the pain took, whether that's the drive down to St. George without pulling off at every exit, a ski day in Little Cottonwood Canyon, or shoveling the driveway in January, with position and movement habits to keep working on afterward.
How Mecham Chiropractic decides whether it's working
This is where all that research turns into a rule.
A plan at Mecham Chiropractic starts with an exam that screens out people who shouldn't be on the table, followed by a course of 20 to 30 sessions spread across 8 to 12 weeks. The checkpoint comes at treatments 8 to 12. Without meaningful improvement by then, the plan gets reconsidered instead of run to the end.
Remember Wang's 63%? It's a reason for humility in both directions. The checkpoint keeps you from paying for sessions that aren't helping, and the natural-healing numbers keep us, and you, from handing the table all the credit when a disc settles down.
What the sessions feel like, soreness included, is on what to expect from spinal decompression. Dealing with a herniated disc? Start with the condition itself, then book an exam.