Vertebral axial decompression (also referred to as mechanized spinal distraction therapy) is used as traction therapy to treat chronic low back pain. Specific devices available are described in the Regulatory Status section.

In general, during treatment, the patient wears a pelvic harness and lies prone on a specially equipped table. The table is slowly extended, and a distraction force is applied via the pelvic harness until the desired tension is reached, followed by a gradual decrease of the tension. The cyclic nature of the treatment allows the patient to withstand stronger distraction forces compared with static lumbar traction techniques. An individual session typically includes 15 cycles of tension, and 10 to 15 daily treatments may be administered.

Regulatory Status

Several devices used for vertebral axial decompression have been cleared for marketing by the U.S. Food and Drug Administration (FDA) through the 510(k) process. Examples of these devices include the VAX-D®, Decompression Reduction Stabilization (DRS®) System, Accu-SPINA® System, DRX-3000®, DRX9000®, SpineMED Decompression Table®, Antalgic-Trak®, Lordex® Traction Unit, and Triton® DTS. According to labeled indications from the Food and Drug Administration, vertebral axial decompression may be used as a treatment modality for patients with incapacitating low back pain and for decompression of the intervertebral discs and facet joints.

FDA product code: ITH.

Related Policies

• None

Evidence reviews assess the clinical evidence to determine whether the use of technology improves the net health outcome. Broadly defined, health outcomes are length of life, quality of life, and ability to function, including benefits and harms. Every clinical condition has specific outcomes that are important to patients and managing the course of that condition. Validated outcome measures are necessary to ascertain whether a condition improves or worsens; and whether the magnitude of that change is clinically significant. The net health outcome is a balance of benefits and harms.

To assess whether the evidence is sufficient to draw conclusions about the net health outcome of technology, two domains are examined: the relevance, and quality and credibility. To be relevant, studies must represent one or more intended clinical use of the technology in the intended population and compare an effective and appropriate alternative at a comparable intensity. For some conditions, the alternative will be supportive care or surveillance. The quality and credibility of the evidence depend on study design and conduct, minimizing bias and confounding that can generate incorrect findings. The randomized controlled trial (RCT) is preferred to assess efficacy; however, in some circumstances, nonrandomized studies may be adequate. RCTs are rarely large enough or long enough to capture less common adverse events and long-term effects. Other types of studies can be used for these purposes and to assess generalizability to broader clinical populations and settings of clinical practice.

Vertebral Axial Decompression for Chronic Lumbar Pain
Clinical Context and Therapy Purpose

The purpose of vertebral axial decompression is to provide a treatment option that is an alternative to or an improvement on existing therapies, such as standard conservative therapy, in patients with chronic lumbar pain due to disc-related causes.

The question addressed in this policy is: Does vertebral axial decompression improve the net health outcome in individuals with chronic lumbar pain due to disc-related causes?

The following PICO was used to select literature to inform this policy.

Patients

The relevant population of interest is individuals with chronic lumbar pain due to disc-related causes.

Interventions

The therapy being considered is vertebral axial decompression.

Vertebral axial decompression applies traction to the vertebral column to reduce intradiscal pressure, and in doing so, potentially relieves low back pain associated with herniated lumbar discs or degenerative lumbar disc disease.

Vertebral axial decompression is administered by chiropractors, osteopaths, physicians, and physical therapists.

Comparators

Comparators of interest include standard conservative therapy.

Conservative management includes nonsteroidal anti-inflammatory medications, back braces, and physical therapy; other nonsurgical treatments could include muscle relaxants, narcotic pain medications, or epidural steroid injections.^1,

Patients with chronic lumbar pain are managed by physicians, orthopedists, osteopaths, chiropractors, and physical therapists,

Outcomes

The general outcomes of interest are symptoms, functional outcomes, quality of life, and treatment-related morbidity.

Follow-up for patients receiving vertebral axial decompression would ideally be 6 months or longer.

Study Selection Criteria

Methodologically credible studies were selected using the following principles:

1. To assess efficacy outcomes, comparative controlled prospective trials were sought, with a preference for RCTs.
2. In the absence of such trials, comparative observational studies were sought, with a preference for prospective studies.
3. To assess long-term outcomes and adverse events, single-arm studies that capture longer periods of follow-up and/or larger populations were sought.

Review of Evidence
Randomized Controlled Trials

Schimmel et al (2009) published results from a randomized sham-controlled trial of intervertebral axial decompression.^2, Sixty subjects with chronic symptomatic lumbar disc degeneration or bulging disc with no radicular pain and no prior surgical treatment (dynamic stabilization, fusion, or disc replacement) were randomized to a graded activity program with an Accu-SPINA device (20 traction sessions during 6 weeks, reaching >50% of body weight) or to a graded activity program with a nontherapeutic level of traction (<10% body weight). In addition to traction, the device provided massage, heat, relaxing blue light, and music during the treatment sessions. Neither patients nor evaluators were informed about the intervention received until after the 14-week follow-up assessment and the intention-to-treat analysis was performed (93% of subjects completed follow-up). Both groups showed improvements in validated outcome measures (visual analog scale scores for back and leg pain, Oswestry Disability Index, 36-Item Short-Form Health Survey) but no significant differences between treatment groups. For example, visual analog scale scores for low back pain decreased from 61 to 32 in the active group and from 53 to 36 in the sham group. Evidence from this RCT did not support improvements in health outcomes with vertebral axial decompression.

Isner-Horobeti et al (2016) reported on a preliminary double-blind RCT comparing high-force traction (50% body weight; n=8) with low-force traction (10% body weight; n=9) for individuals with acute low back pain and radiculopathy due to lumbar disc herniation.^3, Patients were enrolled from a French emergency department. Inclusion criteria were lumbar sciatica of fewer than 6 weeks in duration, secondary to disc herniation based on clinical exam, confirmed by lumbar tomodensitometry. Patients with clinical neurologic deficits, sciatica due to something other than disc herniation, or abnormalities on tomodensitometry were excluded. For the trial’s primary outcome (reduction in radicular pain measured by a 100-mm visual analog scale), both groups demonstrated significant improvements from baseline to day 28 (see Table 1). However, there was no significant interaction effect (group-by-time) interaction regarding pain reduction. Similar findings were seen for lumbo-pelvic-hip mobility (measured by the finger-toe test), and nerve root compression (measured by the straight leg raise test).

Table 1. Summary RCT Results for Change From Baseline to Day 28

Outcome Measures	High-Force Traction Group (n=8)		Low-Force Traction Group (n=9)
	Value (95% CI)	p	Value (95% CI)	p
Radicular pain (VAS, mm)	-28.8 (-41.8 to -3.7)	<0.001	-34.8 (-52.6 to 017)	<0.001
Lumbar spine mobility (FTT, mm)	-14.4 (-25.6 to -3.1)	<0.10	-17.6 (-28.3 to -7.0)	<0.001
Straight leg raise test (elevation angle)	33.1° (13.3° to 53.0°)	<0.01	36.0° (17.3° to 54.7°)	<0.001

Adapted from Isner-Horobeti et al (2016).^3,
CI: confidence interval; FTT: finger-toe test; RCT: randomized controlled trial; VAS: visual analog scale.

Overall, this trial suggested some rapid short-term within-subject improvements with high-dose lumbar traction. Although lumbar traction was not compared with a placebo, the comparison with low-level traction may approximate a placebo, similar to the Schimmel et al (2009) RCT, which used traction at 10% body weight traction as a placebo. The lack of significant interaction term suggests the active intervention is not associated with improved outcomes. However, the trial’s small size might mean that it was underpowered.

Sherry et al (2001) conducted an RCT comparing vertebral axial decompression (using the VAX-D device) with transcutaneous electrical nerve stimulation.^4, While a 68% success rate was associated with VAX-D compared with a 0% success rate with transcutaneous electrical nerve stimulation, without a true placebo control, the results are difficult to interpret scientifically. In 2007, 2 small randomized trials (N=27, N=64) found little to no difference between patients treated with or without mechanical traction.^5,6,

Summary of Evidence

For individuals who have chronic lumbar pain who receive vertebral axial decompression, the evidence includes randomized controlled trials. Relevant outcomes are symptoms, functional outcomes, quality of life, and treatment-related morbidity. Evidence for the efficacy of vertebral axial decompression on health outcomes is limited. Because a placebo effect may be expected with any treatment that has pain relief as the principal outcome, randomized controlled trials with sham controls and validated outcome measures are required. The only sham-controlled randomized trial published to date did not show a benefit of vertebral axial decompression compared with the control group. The evidence is insufficient to determine the effects of the technology on health outcomes.

SUPPLEMENTAL INFORMATION
Practice Guidelines and Position Statements

No guidelines or statements were identified.

U.S. Preventive Services Task Force Recommendations

Not applicable.

Ongoing and Unpublished Clinical Trials

A search of ClinicalTrials.gov in February 2020 did not identify any ongoing or unpublished trials that would likely influence this review.]
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Horizon BCBSNJ Medical Policy Development Process:

This Horizon BCBSNJ Medical Policy (the “Medical Policy”) has been developed by Horizon BCBSNJ’s Medical Policy Committee (the “Committee”) consistent with generally accepted standards of medical practice, and reflects Horizon BCBSNJ’s view of the subject health care services, supplies or procedures, and in what circumstances they are deemed to be medically necessary or experimental/ investigational in nature. This Medical Policy also considers whether and to what degree the subject health care services, supplies or procedures are clinically appropriate, in terms of type, frequency, extent, site and duration and if they are considered effective for the illnesses, injuries or diseases discussed. Where relevant, this Medical Policy considers whether the subject health care services, supplies or procedures are being requested primarily for the convenience of the covered person or the health care provider. It may also consider whether the services, supplies or procedures are more costly than an alternative service or sequence of services, supplies or procedures that are at least as likely to produce equivalent therapeutic or diagnostic results as to the diagnosis or treatment of the relevant illness, injury or disease. In reaching its conclusion regarding what it considers to be the generally accepted standards of medical practice, the Committee reviews and considers the following: all credible scientific evidence published in peer-reviewed medical literature generally recognized by the relevant medical community, physician and health care provider specialty society recommendations, the views of physicians and health care providers practicing in relevant clinical areas (including, but not limited to, the prevailing opinion within the appropriate specialty) and any other relevant factor as determined by applicable State and Federal laws and regulations.

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Index:
Vertebral Axial Decompression
AMT Therapeutic Table
DRS System
DRX 2000
DRX 3000
DRX9000
IDD (Intervertebral Decompression Device)
Intervertebral Decompression Device (IDD)
Spina System
VAX-D Therapeutic Table

References:
1. Peloza J. Non-Surgical Treatments for Lower Back Pain. Spine-health. https://www.spine-health.com/conditions/lower-back-pain/non-surgical-treatments-lower-back-pain. Updated April 20, 2017. Accessed February 13, 2020.

2. Schimmel JJ, de Kleuver M, Horsting PP, et al. No effect of traction in patients with low back pain: a single centre, single blind, randomized controlled trial of Intervertebral Differential Dynamics Therapy. Eur Spine J. Dec 2009;18(12):1843-1850. PMID 19484433

3. Isner-Horobeti ME, Dufour SP, Schaeffer M, et al. High-force versus low-force lumbar traction in acute lumbar sciatica due to disc herniation: a preliminary randomized trial. J Manipulative Physiol Ther. Nov - Dec 2016;39(9):645-654. PMID 27838140

4. Sherry E, Kitchener P, Smart R. A prospective randomized controlled study of VAX-D and TENS for the treatment of chronic low back pain. Neurol Res. Oct 2001;23(7):780-784. PMID 11680522

5. Fritz JM, Lindsay W, Matheson JW, et al. Is there a subgroup of patients with low back pain likely to benefit from mechanical traction? Results of a randomized clinical trial and subgrouping analysis. Spine (Phila Pa 1976). Dec 15 2007;32(26):E793-800. PMID 18091473

6. Harte AA, Baxter GD, Gracey JH. The effectiveness of motorised lumbar traction in the management of LBP with lumbo sacral nerve root involvement: a feasibility study. BMC Musculoskelet Disord. Nov 29 2007;8:118. PMID 18047650

7. Centers for Medicare & Medicaid Services. National Coverage Decision (NCD) for Vertebral Axial Decompression (VAX-D) (160.16). 1997; https://www.cms.gov/medicare-coverage-database/details/ncd- details.aspx?NCDId=124&ncdver=1&DocID=160.16&ncd_id=160.16&ncd_version=1&basket=ncd*3a%24160.16 *3a%241*3a%24Vertebral+Axial+Decompression+(VAX-D)&bc=gAAAAAgAAAAAAA%3d%3d&. Accessed February 20, 2020.

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