TECHNOLOGY REVIEW

Traction Devices:

ecently, there has been an aggres-s ive market ing campaign for adevice (DRX9000) that purports

Mark Tyburski, MDPermanente Medical Group, IncDepartment of Physical Medicine andRehabilitation, Spine ClinicRoseville. CA

Venu Akuthota, MDThe Spine Center at the University ofColorado HospitalAurora. CO

This review investigates

the evidence supporting

utilization of this "new"device as well as other

technologically similar

devices described for the

treatment of low back pain.

It is provided to help spine

care providers come to

a decision on motorized

traction devices such as

DRX9000 andVAX-D.

Marketing a New Breed ofTractionThe DRX9000 is marketed as spinal decom-pression therapy, as opposed to spinal trac-tion therapy, because it provides alternatingcycles of distraction and relaxation insteadof a constant traction force. The theory be-hind this system is that, through the cyclicprocess of distraction and relaxation, thereis pressure relief of spinal structures thatmay be pain generators (eg, intervertebraldisc). Devices in this decompression ther-apy category include VAX-D, DRX2000,DRX3000, DRX5000, DRX9000, Tru Trac401, Lordex PowerTraction Equipment andSpineRx LDM. Our contention, like theone formulated by the FDA, is that thesedecompression devices are akin to distrac-tion or motorized traction devices.

Its marketers have touted the DRX9000as the only device cleared by the FDAto provide "True Non-Surgical SpinalDecompression."l However, this attemptto differentiate this device from others ispurely semantic as a review of their 510 (k)filing reveals that the only difference was theaddition of the tag line "True Non-SurgicalSpinal Decompression" to the name and ap-plication. The class II FDA approval of theDRX9000 and its derivatives appears to bebased on the predicate device, ie, VAX-D,as all these devices are based on the sameprinciples of operation. The majority of thepeer-reviewed literature evaluating spinaldecompression is based on the study of theVAX-D device. The results can generally beapplied to any of the devices in the decom-pression therapy category.

Motorized Lumbar

What's the Evidence?

using "space age technology" to provide" surgical decompression without surgery. "The DRX9000 is one of a number of spinal"distraction or decompression" devices cur-rently in use in the medical community.

The Food and Drug Administration(FDA) subjects these devices to their classII controls. As with other devices in this cat-egory such as power wheelchairs, infusionpumps and surgical drapes, class II controlsmay include special labeling or postmarketsurveillance requirements.

The DRX9000 is distributed by AxiomTechnologies \(orldwide. Advertisementsfrom Axiom and clinics that purchase andpromote this device make claims such as:"The DRX9000rM is clinically proven tohave an 867o success rate with patients suf-fering from lower back pain."l

' ihis market-

ing blitz has led to numerous inquiries frompatients to their spine physicians. The costof this intervention ranges into several thou-sands of dollars and is not covered by mostinsurance carriers. Spine physicians serve amajor role in advising often desperate lowback pain patients on the cost/benefit ratioof new interventions.

This review investigates the evidencesupporting utilization of this "new" deviceas well as other technologically similardevices described for the treatment of lowback pain. It is provided to help spine careproviders come to a decision on motorizedtraction devices such as DRX90O0 andVAX-D.

36 SPINELINE NoVEMBEWDECEMBER 2006

Proposed Mechanisms of Action. Thedescription of the DRX9000 from Axi-om S(orldwidet }[eb site makes curiousclaims regarding the mechanisms of painrelief. The product description states:

Tbe DRX9000rM is a nonsurgi-cal, noninoasioe procedure tbatwas dezteloped. for the treatrnentof lower back pain cawsed by d,iscberniations, degenerathte disc d.is-ease, sciatica and posterior facetsynd.ronxe. Tbe process has beenpronen to relieoe pain by enlargingintradiscal space, redwcing bernia-tion, str e n gtb enin g o wter ligame ntsto help rnove herninted areas backinto place, and reaersing higb intra-discal presswre s tbrougb applicationof negatioe pressure.l

What is the Evidence?The c la im that th is decompression ortraction process reduces intradiscal pres-sure is controversial. Ramos and Martin2performed a case series measuring theintradiscal pressure of L4-5 interver-tebral disc of five patients prior to andduring traction on the VAX-D table.They only published data on three ofthe five patients. They found an inverserelationship between traction force andintradiscal pressure. However, Anders-son et al3 found that intradiscal pressureremains near baseline measurements withpassive traction and actually increaseswith active traction. Some may arguethat these negative findings were likelya result of muscular contraction duringthe manually applied traction and thatthis effect may be mitigated by the cyclicdistraction/relaxation nature of decom-pression therapy tables.

In addition, the statement, "revers-ing high intradiscal pressures throughapplication of negative pressure," in-sinuates that high intradiscal pressure isobserved in patients with low back pain.However, the opposite has been noted.Sato et al4 and Paniabi5 have shown thatintradiscal pressure is actually lower indegenerative discs than in normal discs.Theoretically, decompression/distrac-tion may reduce intradiscal pressure

A 2006 Cochrane review of

24 randomized controlled

trials on Yarious forms of

lumbar traction concluded

that there was strong

evidence that traction as a

single treatment is no more

effective than placebo, sham,

no treatments or other

treatments for patients with

low back pain who may or

may not have sciatica.

in those with a so-called high pressuredisc, as measured on discography withmanometry, rather than in a degenerativedisc. A 2001 study appears to supportthe contention that VAX D treatmenttemporarily decompresses the nerveroots in that dermatomal somatosensoryevoked potentials appeared to improveafter intervention.6

A recent systematic review focusingon spinal decompression via motorizedtactionfor chronic discogenic low backpainwas published in the September2006issue of Pain Praaice.T The article wasfunded in part by Axiom \(orldwide, thedeveloper of the DRX900O. It is the firstto focus specifically on motorized trac-tion devices and analyzed the data fromseven randomized controlled trails oflow quality and three case series studiesof low quality. Six of the seven random-ized studies reported no difference withmotorized "spinal decompression," withthe other study reporting reduced painbut not reduced disability. The three caseseries studies (without control groups)reported 77%-86% reduction in pain.The article concluded that" data suggestthat the efficacy of spinal decompres-sion achieved with motorized tractionfor chronic discogenic low back painremains unproved."T

The \florkers' Compensation Board(\fCB) of Brit ish Columbia, Canada,evaluated the use of vertebral axial de-compression for low back pain in 2005.8The VCB Evidence Based Pract iceGroup conducted "a systematic reviewon the effectiveness of VAX-D in treat-ing low back pain associated with lumbardisc herniation, degenerative disc disease,posterior facet syndrome, sciatica orradiculopathy."8 They concluded thereis no evidence that the VAX-D systemis effective in treating chronic low backpain caused by the aforement ionedconditions.

A 2006 Cochrane review of 24 ran-domized controlled trials on variousforms of lumbar traction concluded thatthere was strong evidence that tractionas a single treatment is no more effec-tive than placebo, sham, no treatmentsor other treatments for patients withlow back pain who may or may nothave sciatica.9 However, lumbar trac-tion continues to be utilized by physicaltherapists, and chiropractic and medicalphysicians based on empiric, anecdotalevidence. As with most treatments forspinal disorders, there may be a subsetof individuals who benefit from lumbartraction. Fritz and Georgel0 describeda clinical prediction rule to determine iflumbar traction is appropriate for somecases of lumbar radiculopathy.

The efficacy of DRX9000 therapy hasnot been studied in randomized trials.Claims made by Axiom \florldwide andpractitioners marketing the DRX9000device are based on a single uncontrolledstudy of 219 patients published in Or-tbopedic Tecbnology Reoiew (O7R;.ttOZR is not a peer-reviewed journal,but a newsletter targeted at orthopedicpractitioners and health care administra-tors. self-touted as a "showcase for newproducts and a source of indusry newsto help improve the economics of theorthopedic practice."

In the OZR study, subjects completeda recommended protocol that included20 treatments of "spinal decompression"over six weeks. The treatment sessionsincluded 45 minutes on the equipment

N OVEMBE R/DECEMB E R 2006 SPINELINE 37

followed by 15 minutes of ice and inter-ferential current therapy "to consolidatethe lumbar paravertebral muscles."11 Inaddition, appendix A of the study de-scribed the treatment protocol as provid-ing a daily predecompression myofascialrelease session using vacuu m/ interfer-ential current treatment for 30 minuteswith heat application. During the initialtwo weeks of the study period, patientswere instructed to wear lumbar supportbelts, limit activities, were placed on lightduty at work and were prescribed ananti-inflammatory medication. After twoweeks. "medication was decreased" andmoderate activity was permitted.

The authors reoorted successful treat-ment in 86o/. of tie219 patients. Successwas defined as a reduction in pain to Oor 1 on the Oswestry Pain Scale (pre-sumably referring to the Pain Intensityquestion on the Oswestry Disabil ityIndex). They also reported completeresolution of pain, normalized lumbarrange of motion and recovery of any sen-sory or motor loss. However, there is nodocumentation or quantification of thereported pretreatment sensory or motorloss in the article. The report mentionsthat 3 1 patients reported significant painand disability despite some improvementin their overall pain and disability score.They did not qualify how they measureddisability and there was no mention ofthe complete Oswestry Disability Indexas being utilized in the study. From thisreport, the authors conclude that "withthe biotechnological advances of spinaldecompression, symptoms were restoredby subjective report in 86"/" of patientspreviously thought to be surgical candi-dates and mechanical function was re-stored in 92"/" using objective data. "1 1

At best, the Gionis study may beconsidered Level IV evidencel2 becauseof its methodology as an uncontrolledcase series study. They study has obviousshort-comings including lack of a controlgroupr incomplete presentation of dataand the confounding use of concomitanttherapies including activity restriction,lumbar support belts, anti-infl ammatorymedications, ice packs and interferential

These devices'efficacy in the

management of low back

or radicular pain remains

unsuPPorted in the peer

reviewed literature. . . This

lack of proven clinical efficacy

should be seriously considered

before referring or seconding a

recommendation that a patient

pay out-of-pocket for these

therapies.

therapy before and after each treatmentsession.

Incidentally, the use of interferentialtherapy with motorized decompressiontype traction is a common practice inGermany. To evaluate the effectiveness ofthese treatments in isolation, lwerners etall3 conducted a randomized controlledtrial comparing motorized decompres-sion type traction therapy plus massagewith interferential therapy. They foundno significant difference in outcomesbetween the two groups.

RisksMotorized controlled traction devicesare not completely risk free. The VAX-D Veb site (www.vaxd.net) states thatnot one single patient has sustained aninjury since the first VAX-D treatmentin1987. Howevet Deen et all4 reportedon sudden progression of a lumbar discprotrusion during VAX-D treatment.During a patient's fifth treatment, hisradicular pain abruptly increased to10/10 on the visual analog scale (VAS)and VAX-D therapy was discontinued.Repea t magne t i c resonance imag ingrevealed an extrusion with a caudally mi-grated fragment. The patient underwentmicrodiscectomy and the VAS scorereduced to 0/10 at six weeks.

Insurance Coverage and BillinglssuesPrivate health insurance companies suchas Aetna. Blue Cross of California andthe Regency Group consider the VAX-D and other "spinal decompression"interventions as experimental treatmentand do not provide reimbursement forthis service. The out-of-oocket cost runsapproximately $200 periession, with therecommended protocol being 20 sessionsfor a total cost of approximately $+OOO.

Axiom rVorldwide partners with acompany named Peer Review Networkto provide insurance billing guidance topractitioners who own the DRX9000device. In addition, Peer Review Net-work publishes a document entit led"PRN Newsletter" which attempts topromote the insurance coverage bf th"DRX9000 through CPT code *97799,"

an "Unlisted Physical Medicine/Reha-bilitation Procedure." for 26 RVUs at areimbursement of $284 per session. PeerReview Network's'\7eb sitels describestheir medical technology assessmentservice which they offer to medical de-vice manufacturers in an attempt to helpestablish successful reimbursement withinsurance companies.

Conclus ionMyriad decompression-type poweredtract ion devices are on the market ,including the DRX9O00 and VAX-D.These devices' efficacy in the manage-ment of low back or radicular Dainremains unsupported in the p. . i r . -viewed literature. There may be a rolefor traction in some cases of low backpain; however, there is no current datato support these devices as being moreeffective than manual traction. Thislack of proven clinical efficacy shouldbe seriously considered before referringor seconding a recommendation thata patient pay out-of-pocket for thesetherapies.

38 SPINELINE NOVEMBER/DECEMBER 2006

References1. Axiom Vorldwide homepage. Available

at: www.axiomworldwide.com. AccessedOctober 19, 2006; 1 1:03 pm.

2. Ramos G, Martin 1W. Effects of vertebralaxial decompression on intradiscal pres-sure. J N euroswrg. 1994;81:350-352.

3. Andersson GB, Schultz AB, NachemsonAL. Intervertebral disc pressures duringtraction. Scand J Rebabil Med (Suppl).1983;9 :88-91.

4. Sato K, Kikuchi S, Yonezawa T. Invivo intradiscal pressure measurementin healthy individuals and in patientswith ongoing back problems. Spine.1999 ;24 (23):24 68 -247 4.

5. Panjabi M, Brown M, Lindahl S, et al.Intrinsic disc oressure as a measure ofintegri ty of the lumbar sprne. Spine.1988;13(8):913-917 .

6. Naguszewski \[K, Naguszewski RK,Gose EE. Dermatomal somatosensoryevoked potential demonstracion of nerveroot decompression after VAX-D thera-py. N e uro L Re s. 2Q0l ;23 (7):7 06-7 1 4.

7. Macario A, Pergolizzi JV. Systematicliterature review of spinal decompres-sion via motorized traction for chronic

discogenic low back pain. Pain Pract.2006;6(3):17r-178.Mart in C\f, \ fCB Evidence BasedPractice Group. Vertebral axial decom-pression for low back pain. WorkersCompensation Board of BC, Canada.February 2005.Clarke J, van Tulder M, Blomberg S, et al.Traction for low back oain with or with-out sciatica: an updrt"i syste-atic reviewwithin the framework of the Cochranecollaboration . Sp in e. 2006;3 | (l 4):l 59 1 -

1599.10. Fri tzJ, George S. Theuseof aclassif ica-

tion approach to identify subgroups ofpatients with acute low back pain: inter-rater reliability and short-term treatmentoutcomes. Spine. 2000;25(1 ):1 06.

11. Gionis TA, Groteke E. Spinal decom-pression. Ortbopedic Technology Re-o iew. 2003 ;5 (Nov/Dec):36-39.

12. Levels of Evidence for Primary Research

Question. Adopted by: North AmericanSpine Society, American Academy ofOrthopaedic Surgeons, Pediatric Ortho-paedic Society of North America, Clini-cal Orthopaedics and Related Research,

Journal of Bone and Joint Surgery and

Spine. Av ailable at: http: / /www.spine.orglforms/LevelsofEvidenceFinal.pdf\(erners R, Pynsent PB, Bulstrode CJ.Randomized trial comparing interfer-ential therapy with motorized lumbartraction and massage in the managemencof low back pain in a primary care setting.Sp ine. 1999 ;24(15):157 9 -1 584.Deen HG lr, Rizzo TD, Fenton DS.Sudden progression of lumbar diskprotrusion during vertebral axial decom-pression traction therapy. May CIin Proc.2003 ;7 8 (1 2) :r 5 5 4 - 1 s 5 6.Peer Review Nework, Inc. Medical

Technology Assessmenr. Available at:ww-wpeerreviewnetwork.com.

FDA Device/Drug StatusDRX9000: approved. VAX-D: approved.

Author DisclosuresI M Tyburski: nothing to disclose.r V Akuthota: f-3, Physiatric Association

of Spine. Sports and Occupational Reha-bilitation (PASSOR).

9 .

t J .8 .

t4.

15 .

Disclosure KeyDirea or indirea remunerotion: a. royalties. b. stock ownership (options, warrants). c. consulting fees. d. loans from the sponsor. e. speaking arrangements.Posiaon held in o compony: f. board of directors. g. scientific advisory board. h. other offlce in a company. Support received from sponsors: i. endowments. i.researqh support for investigator salary. k. research support for staff and materials. l, discretionary funds. m. support of clinical stafr or training. n. trips/travel. o. other sponsorship, Degree of Support | . less than $250 per year. 2. $250 up to $ | 0,000 total support (from all sources combined) per year, orless than or equal to 5% company ownership if value of ownership is less than or equal to $ t 0,000. 3. more than $ | Q000 total support (from all sourcescombined) per.year, or more than 5% company ownership.

NOVEMBER,/DECEMBER 2006 SPINELINE 39