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SPINE Volume 26, Number 4, pp 377–386
©2001, Lippincott Williams & Wilkins, Inc.
Lumbar Supports for Prevention and Treatment of Low
Back Pain
A Systematic Review Within the Framework of the Cochrane Back
Review Group
Petra Jellema, MSc,* Maurits W. van Tulder, PhD,* Mireille N. M. van Poppel, PhD,*
Alf L. Nachemson, PhD,† and Lex M. Bouter, PhD*
Study Design: A systematic review of randomized and
nonrandomized controlled trials.
Summary of Background Data: Lumbar supports are
used in the treatment of low back pain, but also to prevent
the onset (primary prevention) or recurrences of a low
back pain episode (secondary prevention).
Objectives: To assess the effects of lumbar sup-
ports for prevention and treatment of nonspecific low
back pain.
Methods: The Medline, Cinahl, and Current Contents
databases; the Cochrane Controlled Trials Register up to
September 1999; and the Embase database up to Septem-
ber 1998 were all searched. References of identified trials
and systematic reviews were reviewed and the Science
Citation Index used to identify additional trials. Method-
ologic quality assessment and data extraction were per-
formed by two reviewers independently. A quantitative
analysis was performed in which the strength of evidence
was classified as strong, moderate, limited or conflicting,
and no evidence.
Results: Five randomized and two nonrandomized
preventive trials and six randomized therapeutic trials
were included in the review. Only 4 of the 13 studies were
of high quality. There was moderate evidence that lumbar
supports are not effective for primary prevention. No ev-
idence was found on the effectiveness of lumbar supports
for secondary prevention. The systematic review of ther-
apeutic trials showed that there is limited evidence that
lumbar supports are more effective than no treatment,
whereas it is still unclear whether lumbar supports are
more effective than other interventions for treatment of
low back pain.
Conclusions: There continues to be a need for high
quality randomized trials on the effectiveness of lumbar
supports. One of the most essential issues to tackle in
these future trials seems to be the realization of adequate
compliance. [Key Words: Cochrane collaboration, effec-
tiveness, lumbar supports, systematic review] Spine
2001;26:377–386
Low back pain (LBP) is a very common health problem
in western industrialized countries. Lifetime prevalence
of LBP exceeds 70%, with peak point prevalences be-
tween ages 35 and 55.
4
Furthermore, recurrent episodes
of LBP occur very frequently, and a considerable number
of people have permanent discomfort from LBP.
4
Chronic LBP is present in 3% to 7% of the population in
western industrialized countries.
4
The impairment and
disability associated with LBP frequently lead to absence
from work and associated loss of productivity. The total
costs of LBP to industry in 1988 in the United States were
estimated to be between $26.8 and $56 billion (US).
26
In
The Netherlands, the total costs of absenteeism and dis-
ability due to back pain—the indirect costs—were esti-
mated at $3.1 billion and $1.5 billion (US), respectively,
in 1991, whereas the total direct medical costs were es-
timated at $368 million (US).
38
Lumbar supports are frequently used in the manage-
ment of low back pain and are also a common interven-
tion in industry to prevent back injuries.
9
Lumbar sup-
ports are provided as treatment to people who have LBP
with the purpose of making the impairment and disabil-
ity vanish or decrease. Lumbar supports are provided as
intervention for prevention with the purpose of prevent-
ing the onset of LBP (primary prevention) or of prevent-
ing recurrent LBP episodes (secondary prevention). Al-
though a large variety of preventive and therapeutic
interventions are available for LBP, the efficacy of most
of these interventions has not been demonstrated
yet.
36,39
Nachemson
27
reported the different desirable func-
tions of a lumbar support: 1) to correct deformity; 2) to
limit spinal motion; 3) to stabilize part of the spine; 4) to
reduce mechanical uploading; and 5) to provide the mis-
cellaneous effects of massage, heat, placebo. However, at
present, the putative mechanisms of action of a lumbar
support remain a matter for debate.
5,7,9,25
Potential adverse effects of wearing a lumbar support
that have been reported, are skin lesions, gastrointestinal
disorders and muscle wasting,
7
higher blood pressure
and higher heart rates.
23
The growing popularity of lumbar supports has led to
several studies investigating the preventive and therapeu-
tic effects. These studies have already been summarized
in several reviews, papers, and editorials on the effective-
ness of lumbar supports for prevention
5,9,19,25,36
and for
treatment.
20
The present systematic review distinguishes itself
from these reviews by evaluating the literature systemat-
ically using the up-to-date methodology recommended
by the Cochrane Collaboration Back Review Group
40
,
by including the most recent literature up to September
From the *Institute for Research in Extramural Medicine, Vrije Uni-
versiteit, Amsterdam, The Netherlands; and the †Department of Or-
thopedics, Sahlgrenska University Hospital, Göteborg, Sweden.
Potential conflict of interest: Mireille van Poppel is the first author of
one of the trials included in this review. Methodologic quality assess-
ment and data extraction of this trial were conducted by two other
reviewers (PJ, MWvT).
377
1999, and by reviewing lumbar supports in the context
of both treatment and prevention.
The objectives of this systematic review were to deter-
mine whether lumbar supports are effective for preven-
tion of nonspecific LBP and whether lumbar supports are
effective for treatment of nonspecific LBP. Comparisons
that were investigated were:
1a. Lumbar support as intervention for prevention of
LBP versus no intervention.
1b. Lumbar support as intervention for prevention of
LBP versus other types of prevention.
1c. Lumbar support as supplement to another type of
prevention of LBP versus the other type of preven-
tion alone.
2a. Lumbar support as intervention for treatment of
LBP versus no intervention.
2b. Lumbar support as intervention for treatment of
LBP versus other types of treatment.
2c. Various types of lumbar support.
Methods
Criteria for Considering Studies.
Types of Studies. Both randomized controlled trials (RCTs)
and nonrandomized controlled trials (CCTs) were included.
The CCTs were included because of the small number of avail-
able RCTs. There were no language restrictions.
Types of Participants. For preventive trials, the study pop-
ulation had to consist of workers aged 18 to 65 years. For
therapeutic trials, the study population had to consist of sub-
jects with nonspecific low back pain. The RCTs and CCTs that
included subjects with low back pain caused by specific patho-
logic entities such as infection, neoplasm, metastasis, osteopo-
rosis, rheumatoid arthritis, or fractures were excluded.
Types of Interventions. Any type of lumbar support, flexible
and rigid, for prevention or treatment of nonspecific LBP was
included. Special types of lumbar supports for severe scoliosis
and kyphosis were excluded, as were special lumbar supports
after back surgery.
Types of Outcome Measures. Only preventive studies in
which at least one of the following outcome measures was used
were included: incidence of low back pain, duration of low
back pain, absenteeism (percentage of the studied population,
number of days), and back-pain–specific functional status (Ro-
land Disability Questionnaire [RDQ], Oswestry scale). For
therapeutic studies only RCTs and CCTs that used at least one
of the following outcome measures were included: pain (visual
analog scale [VAS], numerical rating scale [NRS]), overall im-
provement (percentage improvement, NRS), return to work
(percentage of the population, number of days of absenteeism)
and back pain specific functional status (RDQ, Oswestry
scale).
Search Strategy for Identification of Studies. Searches of
Medline, Cinahl, and Current Contents databases; the Co-
chrane Controlled Trials Register up to September 1999; and
the Embase database up to September 1998 were conducted.
The search strategy recommended by the Editorial Board of the
Cochrane Back Review Group was used.
40
Also screened were
references in relevant reviews and identified trials, and the Sci-
ence Citation Index was used to identify additional trials.
Methods.
Study Selection. Two reviewers (PJ, MWvT) ran the com-
plete search strategy in Medline and Embase together. One
reviewer (PJ) ran the search in Cinahl and Current Contents.
Authors, title, subject headings, publication type, and abstract
of the studies identified by the search strategy were down-
loaded. Studies that met the inclusion criteria were included
in the review. A consensus method was used to resolve dis-
agreements about the inclusion of studies, and a third reviewer
(MNMvP) was consulted if disagreement persisted.
Methodologic Quality Assessment. The methodologic qual-
ity was independently assessed by two reviewers (PJ, MWvT).
The reviewers were not blinded as to author, institution, and
journal, because one of the quality assessors (MWvT) was very
familiar with the literature and would have recognized blinded
studies easily. The other quality assessor (PJ) was a layperson in
the field of intervention research on back pain and not familiar
with the literature. A consensus method was used to resolve
disagreements concerning the assessment of the methodologic
quality of the RCTs and CCTs included in the review. A third
reviewer (MNMvP) was consulted if disagreement persisted. If
the article did not contain sufficient information on one or
more of the criteria, the authors were contacted for additional
information. If the authors could not be contacted or if the
information was no longer available, the criteria were scored as
unclear.
The methodologic quality of the studies was assessed using the
criteria list recommended by the Cochrane Back Review Group
for Spinal Disorders.
40
Only the items reflecting the internal va-
lidity of the RCTs and CCTs were used to assess the methodologic
quality (see Table 1). The item regarding the blinding of care
providers was not included in the quality assessment, because
blinding of care providers for lumbar support use seems impossi-
ble. Each item was scored as either positive, negative, or unclear. A
validity item was scored as positive when the available informa-
tion regarding that item did not show any bias and negative when
no information at all was provided regarding that item or when
the available information showed any bias. A validity item was
scored as unclear when the available information regarding that
item was too scarce to make a conclusion regarding potential bias.
Table 1. Methodologic Quality Criteria
Internal Validity Items
1 Was a method of randomization performed?
2 Was the treatment allocation concealed?
3 Were the groups similar at baseline regarding the most important
prognostic indicators?
4 Was controlled for cointerventions which could explain the
results?
5 Was the compliance rate (in each group) unlikely to cause bias?
6 Was the patient blinded?
7 Was the outcome assessor blinded?
8 Was the withdrawal/dropout rate unlikely to cause bias?
9 Was the timing of the outcome assessment in both groups
comparable?
10 Was an intention-to-treat analysis used?
378 Spine · Volume 26 · Number 4 · 2001
Data Extraction. Using a standardized form, one reviewer
(PJ) extracted data considering characteristics of the study pop-
ulation (age, gender), type of work performed by the study
population (in prevention trials), type of LBP (with or without
radiation, in treatment trials), duration of LBP (acute or
chronic, in treatment trials), type of study (RCT or CCT), du-
ration of intervention period, timing of follow-up measure-
ments, characteristics of the studied intervention (type of lum-
bar support, the number of hours per day the subjects were
prescribed to wear the lumbar support, duration of interven-
tion period), characteristics of the control intervention (type,
intensity, duration of intervention period), adverse effects due
to the interventions, compliance, and the final results for each
outcome measure on the effectiveness of lumbar supports. The
reviewer compared these findings to data regarding the same
characteristics of the same studies published in other re-
views.
20,36
The reviewer was not blinded as to author, institu-
tion, and journal of the reviews.
Data Analysis. Many studies did not report the results in a
way that enabled statistical pooling (for example, means with
standard deviations for continuous data). Furthermore, studies
were heterogeneous in study populations, interventions, and
outcomes. Therefore, a meta-analysis was not performed, but
the results were summarized qualitatively. A rating system was
used, consisting of four levels of scientific evidence based on the
design (RCT or CCT), the quality, and the outcome of the
studies:
1. Strong evidence: provided by generally consistent find-
ings in multiple high-quality RCTs.
2. Moderate evidence: provided by generally consistent
findings in one high-quality RCT and one or more low-
quality RCTs or by generally consistent findings in multiple
low-quality RCTs.
3. Limited evidence: only one RCT (of either high or low
quality) or generally consistent findings in CCTs; or con-
flicting evidence: inconsistent findings in multiple RCTs and
CCTs.
4. No evidence: no CCTs or RCTs.
Multiple high-quality RCTs were defined as more than one
RCT that fulfilled 50% or more of the validity criteria. Sensi-
tivity analyses were also performed exploring the results when
high quality was defined as fulfilling 40% and 60% or more of
the validity criteria. Another sensitivity analysis was performed
in which all scores of “unclear” on the internal validity items
were assumed to be positive. Findings were considered to be
generally consistent when at least 75% of the studies showed
similar results.
Subgroup analyses for prevention were performed for pri-
mary versus secondary prevention and short-term follow-up
(⬍6 months after randomization) versus long-term follow-up
(6 months after randomization). Subgroup analyses for treat-
ment were performed for acute versus chronic LBP and short-
term follow-up (⬍6 months after randomization) versus long-
term follow-up (6 months after randomization).
Results
Study Selection
The search strategy in the four databases resulted in the
identification of 153 articles; 43 articles were identified
in Medline, 93 articles in Embase, 6 articles in Cinahl,
and 11 in Current Contents. Because 17 articles were
found in two databases, 4 articles in three databases, and
1 article in all four databases, the total number of poten-
tially relevant articles was 125. Based on titles, subject
headings, abstracts and journal types, the authors con-
cluded that seven articles met the eligibility crite-
ria.
10,17,21,24,35,37,41
The reviewers disagreed on or were
not sure about inclusion of six studies.
2,13,15,18,22,32
All
six articles were excluded after the full articles were read
(Table 2).
The studies by Hsieh et al
17
and Pope et al
29
appeared
to be reports of the same study. Both studies were used to
assess the quality of the study and to extract relevant
data.
Screening references of two reviews
20,36
resulted in
identification of five additional studies.
1,3,8,31,33
In 1991,
some additional data from the study of Walsh and
Schwartz
42
were published in a letter to the editor.
Screening the latest issue of the Cochrane library, re-
sulted in identification of four RCTs, which had already
been identified. Citation tracking in the Science Citation
Index of the selected RCTs and CCTs resulted in identi-
fication of 42 articles. However, none of these studies
met the inclusion criteria. Two additional studies came
from the authors’ personal files.
12,28
In summary, seven
studies on prevention
1,3,12,31,33,37,41
were included in the
present review and six studies on treatment.
8,10,17,24,28,35
Methodologic Quality
The two quality assessors disagreed about 55 of the 227
validity items (24%). After one consensus meeting, all
disagreements, mostly due to reading errors, were
resolved.
The authors of the studies have been informed about
the methodologic quality assessment. The addresses of
two authors were not found.
10,35
The authors were
asked whether they agreed with the scores and whether
they could provide more information on the items that
were scored as unclear. The authors of four studies re-
sponded to this request.
8,17,24,37
Seven scores were
changed by this information: Four unclear scores and
three negative scores were changed into positive.
Overall the methodologic quality of the studies in-
cluded in the present review was low (Table 3). Only four
Table 2. Characteristics of Excluded Studies
Study Reason for Exclusion
Amudsen, 1982 No control group.
Garg, 1992 The lumbar support was used as intervention for the
transfer of patients and not as intervention for
prevention or treatment of LBP.
Hamonet, 1993 No relevant outcome measures. The effect of a
lumbar support was evaluated by measuring the
activity level of the abdominal muscles.
Jonai, 1997 The effect of a lumbar support was evaluated by
measuring the range and velocity of torso motion.
Larsson, 1980 No contrast for lumbar supports.
Marty, 1998 No contrast for lumbar support.
Spratt, 1993 No contrast for lumbar support.
379Lumbar Supports in Low Back Pain · Jellema et al
of the 13 studies met the preset level for high quality of
more than 50% positive scores.
17,24,37,41
Prevalent
methodologic flaws were inadequate randomization pro-
cedure (items 1), no concealment of treatment allocation
(item 2), no assessment of cointerventions (item 4) and
compliance (item 5), and no blinding of patients (item 6)
and outcome assessors (item 7).
Study Characteristics
Study characteristics are summarized in Table 4.
Prevention
Of the seven preventive studies five were
RCTs,
1,12,31,37,41
and two were CCTs.
3,33
In three stud-
ies, it was reported that workers with a history of LBP
were included, and in two studies it was reported that
workers with current LBP were included. In the other
studies no information was given about inclusion or ex-
clusion of workers with a history of LBP or current LBP.
One study excluded patients who were currently treated
for back pain or back injury.
41
The number and type of control interventions used in
the preventive studies varied considerably. In all studies,
the subjects were prescribed to wear the lumbar support
at work. Only three studies presented data regarding
compliance.
3,31,37
The compliance rate varied from 43%
of the subjects who wore the belt at least half the time
37
to 80% of the subjects who wore the belt most of the
time.
3
In two studies results of subgroup analyses were
presented for subjects with a history of back pain. Van
Poppel et al
37
showed that, within a subgroup of subjects
with LBP at baseline, workers using a lumbar support
had lesser days with LBP per month compared with
workers without lumbar support. Barron
5
suggested, us-
ing data of Walsh and Schwartz
41
, that workers with a
history of LBP may be an appropriate population for
consideration of prophylactic bracing in the workplace
rather than the general workforce.
Treatment
All six studies on treatment were RCTs. None of the
treatment studies included solely patients with acute
LBP, and only one study included solely patients with
chronic LBP.
24
Four studies included a mix of patients
with acute, subacute, and chronic LBP.
8,10,17,35
One
study did not give any information about the duration of
the LBP symptoms of the patients.
28
The lumbar sup-
ports and control interventions used in the studies varied
considerably. One study reported that any type of lum-
bar support was used.
8
Two studies used a lumbar sup-
port with rigid stays in the back,
15,24
whereas one study
used a pneumatic lumbar support.
28
The other two stud-
ies did not provide much information about the type of
belt.
8,35
In the study by Million et al,
24
two types of
lumbar supports were compared. Only three studies re-
ported the number of hours a day the lumbar support
should be worn.
17,24,28
Compliance with wearing the
belt was reported in only one study; 56% of the patients
wore the belt more than 7 hours a day.
17
Effects of Lumbar Supports in Prevention of Low
Back Pain
Lumbar Supports
Versus
No Intervention. Four
RCTs
1,12,31,37
and one CCT
3
included a no intervention
group. One RCT was considered to be a high-quality
RCT,
37
whereas three studies were considered to be low-
quality RCTs.
1,12,31
None of these studies evaluated
lumbar supports for secondary prevention and, there-
fore, a subgroup analysis for primary versus secondary
prevention was not performed.
Four RCTs reported no differences in back pain injury
or incidence of LBP after 3 months,
1
6 months,
37
8
months,
31
and 12 months.
12
In three RCTs, including
the high-quality study, no differences were found in sick
leave.
12,31,37
There is moderate evidence (Level 2) that
lumbar supports do not prevent LBP.
Lumbar Support
Versus
Other Types of Prevention. Two
RCTs were identified, one of high quality
37
and one of
low quality.
31
In both, incidence of LBP and sick leave
due to LBP were used as outcome measures. In both
trials, these outcome measures did not show significant
differences between intervention and control groups.
There is moderate evidence (Level 2) that lumbar sup-
ports are not more effective than other types of preven-
tion for LBP.
Lumbar Support as Supplement to Another Type of Prevention
Versus
the Other Type of Prevention. In two studies lumbar
support plus back school was compared with the back
school program alone in the prevention of low back
pain.
33,41
In one of these trials, all subjects also were
instructed in warming-up exercises.
33
One trial was con-
sidered a high-quality RCT,
41
the other trial was a
CCT.
33
In both studies incidence of LBP (work injury)
was used as an outcome measure, and in one of these,
days absent from work because of back injury was also
used as an outcome measure.
33,41
In both trials there was
Table 3. Methodologic Quality of Trials on the
Effectiveness of Lumbar Supports
Studies 12345678910
Prevention of low back pain
Alexander ? ⫺⫹⫺ ?⫺⫺⫹⫹⫹
Anderson ⫺⫺⫺⫺⫹⫺⫺ ?⫹?
Gaber ? ? ⫹⫹⫺⫺⫺⫺⫹⫺
Reddell ? ⫺⫹⫺⫺⫺⫺ ?⫹⫺
Thompson ⫺⫺⫺⫺⫺⫺⫺⫺⫹ ?
Van Poppel ⫹⫹⫹⫺⫺⫺⫺⫹⫹⫹
Walsh ⫹⫺⫹ ?⫺⫺⫹⫹⫹ ?
Treatment of low back pain
Coxhead ⫹⫺ ?⫺⫺⫺⫺⫺⫹⫹
Doran & Newell ????⫺⫺⫹⫺⫹⫺
Million ⫹⫹⫺⫺⫺⫹⫺⫹⫹⫹
Penrose ? ⫹?⫺?⫺⫺⫹⫹⫹
Pope ⫹⫹⫹⫹⫹⫺⫹⫺⫹⫺
Valle-Jones ? ⫺?⫹⫺⫺⫺⫹⫹⫹
380 Spine · Volume 26 · Number 4 · 2001
Table 4. Characteristics of Included Studies
Study Participants Interventions Outcomes Notes
RCTs
Alexander, 1995 Subjects: 60 health care workers; 48 women
and 12 men. Mean age 37 years. Exclusion
criteria: subjects who have had back
surgery, current workers’ compensation
claims, cardiovascular problems, or were
pregnant. Authors did not report whether
workers with LBP or a past history of LBP
were included in the study.
Preventive intervention: 1) Back
belt group (n ⫽30). Belt use at
work for 3 months.
Control intervention: 2) No
intervention (n ⫽30)
Work-related back
injuries and
perception of physical
pain. No significant
differences.
The most common complaints: belt rode
up, changed position, and increased
perspiration. No data available
regarding compliance.
Coxhead, 1981 Subjects: 334 patients with pain of sciatic
distribution; 185 men and 149 women. Mean
age 41.9, mean duration of symptoms 14.3
weeks.
Exclusion-criteria: specific LBP, patients
undergone trunk, lower-limb, or spinal
surgery within the previous 3 months and
pregnant and postpartum women.
Treatment intervention:
1) Fabric made lumbar support, 4
weeks (n ⫽124). No data on
number of hours/day.
Control interventions: 2) No lumbar
support (n ⫽168).
Overall improvement,
pain, return to work/
normal activities. No
differences after 4
weeks, 4 months, and
16 months.
334 patients entered the study, 12 were
later found ineligible. Of these 322
patients, 292 were assessed at 4
weeks. At 4 months 250 patients were
assessed and at 16 months 258
patients were assessed. No data
available regarding compliance.
Doran, 1975 Subjects: 456 patients with nonspecific LBP; 211
women, 245 men. Age 20–50, duration of
symptoms: less than a week to more than 6
months.
Inclusion criteria: 1) age 20–50 years, 2) painful
limitation of movement in the lumbar spine
and 3) suitable for any treatment.
Treatment interventions: 1) Corset
(⫽109), any type, 3 weeks. No
data on number of hours/day.
Control interventions:
2) Manipulation (n ⫽116), 2
treatments/wk
3) Physiotherapy (n ⫽114), any
treatment except manipulation,
two treatments/wk
4) Analgesic tablets (n ⫽113) 2
paracetamols/4 hours.
Pain
Overall assessment by
the doctor. No
significant differences
after 3 and 6 weeks,
and 3 and 12 months.
456 patients entered the trial. At
baseline 452 patients were assessed.
After 3 weeks 395 patients were
assessed, after 6 weeks 340, after 3
months 335, and after 12 months 262
patients were assessed.
No data available regarding compliance.
Gaber, 1999 Subjects: 209 male workers whose jobs
included manual material handling at an
airport. The majority of the workers (77%)
had no or only mild LBP at the start of the
study.
Preventive intervention: 1)
Synthetic lumbar support
(n ⫽118), lumbar support use at
work for 12 months.
Control intervention: 2) No
intervention (n ⫽91)
Pain score, medicine
intake due to LBP,
sick leave due to LBP.
No differences in pain
and sick leave; less
medication intake in
lumbar support group.
Of the 267 workers included at the start
of the study only 209 have finished
the study. Only data of these subjects
is presented in the study. No data on
compliance.
Hsieh, 1992 Subjects: 164 patients, 62 women and 102 men
with nonspecific LBP and no sciatica.
Median age 32 and mean duration of
complaints between 3 weeks and 6 months.
Inclusion criteria: 1) age 18–55 years, 2) LBP
between 3 weeks and 6 months duration, 3)
good health.
Treatment intervention: 1) Corset
(n ⫽29), lumbosacral canvas
corset with metal stays in the
back. Corset use during waking
hours, 3 weeks.
Control interventions: 2) Spinal
manipulation (n ⫽70), 3 times/
week. 3) Soft tissue massage
(n ⫽37), 3 times/week. 4) TMS
(n ⫽28), unit should be worn
for 8 hours/day.
Pain, functional status.
Only better functional
status after 4 weeks
compared to
massage, not to
manipulation and
TMS. No differences
in pain.
88% of the original patients completed
the assessments at baseline and at 4
weeks. Data of RDQ and revised
Oswestry are reported by Hsieh (1992)
for a subgroup of 83 patients from the
study population of Pope. Compliance:
65% wore the belt more than 7 hours
a day during the intervention period.
Million, 1981 Subjects: 19 patients, 13 women and 6 men. No
data available on mean age. Inclusion
criteria: 1) over 18 years of age, 2) suffering
from chronic nonspecific LBP 6 months, 3)
not responding to any form of treatment.
Treatment intervention: 1) Corset
and lumbar support (n ⫽9).
Support is of rigid material.
Corset use during the day, 8
weeks.
Control intervention: 2) Corset
(n ⫽10), lumbosacral corset use
during the day, 8 weeks.
Subjective and objective
index. Rigid support
better subjective
index after 4 and 8
weeks.
The subjective index is an overall
measurement of the severity of
symptoms and of the interference of
these symptoms with normal
activities.
The objective index is an overall
measurement of the straight leg
raising and of spinal movements.
No data on compliance.
Penrose, 1991 Subjects: 30 patients, 8 women and 22 men.
Mean age 34 years (range 19–61 years).
Patients were diagnosed as having muscular
strain/sprain of the lower back by an
orthopedic-neurologic examination. No
information available on mean duration of
complaints.
Treatment intervention: 1)
Pneumatic lumbar support
(n ⫽15). Lumbar support use
during 6 hours/day, 5
days/week, 6 weeks.
Control intervention: 2) No
intervention.
Pain index; lumbar
supports better after 1
hour, 3 weeks, and 6
weeks.
No data on compliance.
381Lumbar Supports in Low Back Pain · Jellema et al
no significant difference between the two intervention
groups regarding incidence of LBP (work injury). In the
high-quality study, a significant effect was found of wear-
ing the belts in addition to a back school program on the
number of days absent from work because of back inju-
ry.
41
Regarding the incidence of LBP, there is limited
evidence (Level 3) that a lumbar support added to a back
school program is not more effective than a back school
program alone. However, there is limited evidence (Level
3) that a lumbar support added to a back school program
Table 4. Continued
Study Participants Interventions Outcomes Notes
Reddell, 1992 Subjects: 896 fleet service clerks; 70
women, 572 men. Age range: 19–67
years. 26% of 642 subjects had
suffered a previous back injury and
56% a previous back pain. No data
available regarding subjects with
current LBP.
Preventive intervention: 1)
Weightlifting belt (n ⫽145), belt
use at work, 8 months. 2) Belt
plus training class (n ⫽127),
belt use at work and 1 hour
training class on spine anatomy
and body mechanics.
Control intervention: 3) Training
class (n ⫽122), 1 hour training
class. 4) No intervention
(n ⫽248).
Lumbar injuries, lost
work days case
lumbar injury,
restricted work days,
case lumbar injury,
compensation cost.
No significant
differences after 8
months.
Of the 896 clerks selected to participate
in this study 642 were located and
interviewed at the end of 8 months.
Only data of these subjects is
presented in the article.
Compliance: 58% stopped using it before
the end of 8 months.
Complaints: heat production around the
waist, the belt rides up and pinches
ribs.
Valle-Jones, 1992 Subjects: 216 patients with nonspecific
LBP; 97 women, 113 men and 6
“unknown.” Mean age 43, median
duration of symptoms 11 days.
Inclusion criteria: 1) first episode of
nonspecific LBP, 2) chronic
nonspecific LBP, 3) acute
exacerbation of a longer-standing
problem.
Treatment intervention: 1) Back
support (n ⫽111), elasticated
with an attached silicone
rubber pad of special shape, 3
weeks.
Control intervention: 2) Standard
therapy: advice on rest and
lifestyle (n ⫽105).
Pain, limitation of
activity, ability to
work, use of
analgesics, overall
improvement; all
significantly better in
lumbar support group
after 3 weeks.
No data on compliance.
Van Poppel, 1998 Subjects: 312 workers whose jobs
included manual material handling.
Workers who had a permanent
partial work disability were excluded.
Mean age 35.1. 172 subjects with
previous LBP, 49 subjects with LBP
at baseline.
Preventive interventions: 1)
Lumbar support (n ⫽83), 6
months. 2) Lumbar support use
at work plus education (n ⫽70),
6 months.
Control intervention: 3) Education:
5 hrs. lifting instructions
(n ⫽82). 4) No intervention
(n ⫽77).
LBP incidence, sick
leave due to back
pain; no differences
after 6 months.
A total of 312 workers were randomized
of whom 282 were available for the
6-month follow-up. Compliance with
wearing the lumbar support at least
half of the time was 43%.
Walsh, 1990 Subjects: 90 male warehouse workers.
Individuals currently being treated for
back pain or back injury were
excluded, although those with a prior
history of back injury were not
excluded. Mean age 29 years.
Preventive intervention: 1) A
lumbosacral orthosis at work
plus back school: a 1-hr training
session on back pain prevention
and body mechanics, 6 months
(n ⫽30).
Control intervention: 2) Back
school (n ⫽30), 1-hr. training
session. 3) No intervention
(n ⫽30).
Work injury incidence,
productivity, use of
health care services,
days lost from work
by back injury. Days
lost from work
significantly better in
lumbar support group.
A total of 90 workers were randomly
assigned. Follow-up was obtained at 6
months from 82 workers. Only the
data of these 82 workers is presented
in the article. No data on compliance.
CCTs
Anderson, 1993 Subjects: 266 workers in a grocery
distribution warehouse. No data
available on age. Authors did not
report whether workers with LBP or
a past history of LBP were included
in the study.
Preventive intervention: 1) Back
belt group (n ⫽266)
A spandex belt with shoulder
straps. Belt use at work for 12
months.
Control intervention: 2) No
intervention (2 other work sites).
Lower incidence of
injury in back belt
group.
The supervisors reported that over 80%
of the workers wore the belts most of
the time.
Thompson, 1994 Subjects: 60 hospital workers; both men
and women. Authors did not report
whether workers with LBP or a past
history of LBP were included in the
study. Age range 21–65 years.
Preventive intervention: 1)
Weightlifting belt plus 8 hrs.
back school and instructions on
warm-up exercises (n ⫽41),
thick woven, deformable nylon,
daily use, 3 months.
Control intervention: 2) Back
school and 8 hrs. instructions
on warm-up exercises (n ⫽19).
Incidence of LBP
significantly lower in
lumbar support group.
The authors stated that belt use
resulted in less LBP. However, it is
unclear how the authors came to this
conclusion. At baseline a difference in
frequency of LBP already existed. No
data presented.
No data on compliance.
382 Spine · Volume 26 · Number 4 · 2001
is more effective than back school alone regarding the
number of days absent from work because of back
injury.
Effects of Lumbar Supports in Treatment of Low
Back Pain
Lumbar Support
Versus
No Intervention. In one low-quality
RCT the effect of a lumbar support was compared with
no intervention.
28
In this study, the pain index showed a
significant effect in favor of the lumbar support group.
There is limited evidence (Level 3) that lumbar supports
provide some pain relief in patients with low back pain.
Lumbar Support
Versus
Other Types of Treatment. In four
trials lumbar supports were compared with some type of
treatment for LBP.
8,10,17,35
Only one trial was consid-
ered a high-quality RCT.
17
All four studies used pain as
a main outcome measure. Only Valle-Jones et al
35
found
a significant difference in pain in favor of the lumbar
support group. In other three studies, including the high-
quality RCT, no differences were reported. There is mod-
erate evidence (Level 2) that a lumbar support is not
more effective in reducing pain than other types of
treatment.
Overall improvement was used as main outcome mea-
sure in three low-quality studies.
8,10,35
In only one
study
35
was a significantly greater overall improvement
found in the lumbar support group, whereas no differ-
ences were found in the other two studies. There is con-
flicting evidence (Level 3) that patients wearing a lumbar
support do or do not show significantly more overall
improvement than patients receiving another type of
treatment. Return to work (or ability to work) was used
as a main outcome measure in two low-quality stud-
ies.
8,35
In the findings of one study, there was no signif-
icant difference between the groups,
8
whereas in another,
a significant difference was found in favor of the lumbar
support group.
35
There is conflicting evidence (Level 3)
that patients who use a lumbar support as treatment
return to their work more quickly than patients who use
another type of treatment.
In the high-quality study, two different back pain–
specific functional status tests were used.
17
The RDQ
showed a significant difference between the lumbar sup-
port group and the soft tissue massage group. The re-
vised Oswestry Scale showed no significant difference
between the groups. Therefore, there is conflicting evi-
dence (Level 3) on whether lumbar supports improve
back pain–specific functional status compared with
other types of treatment.
Comparison of Different Types of Lumbar Supports. In one
high-quality RCT
24
two different types of lumbar sup-
ports were compared: one with and one without a rigid
insert in the back. Patients wearing the lumbar support
plus rigid insert showed significantly more global im-
provement (on a subjective index) than those without the
rigid insert. There is limited evidence (Level 3) that a
lumbar support with a rigid insert in the back provides
more overall improvement than a lumbar support with-
out a rigid insert in the back.
Sensitivity Analyses
A sensitivity analysis was conducted to evaluate the in-
fluence of different thresholds for high quality on the
overall conclusions. Another sensitivity analysis was
conducted in which all unclear scores on internal validity
items were considered positive.
Different Thresholds for High Quality. When a threshold of
40% was used for studies on prevention, one additional
RCT was considered of high quality,
1
resulting in a total
of three high-quality RCTs.
1,37,41
Consequently, the
conclusion on the comparison of lumbar supports versus
no intervention changed from moderate evidence to
strong evidence that lumbar supports are not more effec-
tive in preventing back injury or LBP than no
intervention.
When using a threshold of 40% for studies on treat-
ment, the studies by Penrose et al
28
and Valle-Jones et
al
35
were also considered of high quality. For the com-
parison of lumbar supports to other types of treatment,
only the conclusion on pain intensity changed from mod-
erate evidence (Level 2) that lumbar supports are not
more effective than other types of treatment to conflict-
ing evidence (Level 3). When compared with no interven-
tion, limited evidence (Level 3) that lumbar supports are
more effective than no intervention changed to moderate
evidence (Level 2).
When a threshold of 60% was used for studies on
prevention, the study by Walsh and Schwartz
41
changed
from a high-quality to a low-quality RCT, but the evi-
dence remained limited (Level 3). Using a threshold of
60% for studies on treatment, conclusions did not
change, because the studies of Hsieh et al
17
and Million
et al
24
were still high-quality studies.
All Unclear Scores Considered Positive. When all unclear
scores were assumed to be positive, four studies on pre-
vention
1,12,37,41
and five studies on treatment
10,17,24,28,35
were considered high-quality RCTs at the 50% cutoff. The
conclusion regarding the comparison of lumbar support
versus no intervention changed from moderate evidence
(Level 2) to strong evidence (Level 1) that a lumbar support
is not more effective in preventing LBP than no
intervention.
The conclusion regarding the comparison, lumbar
support versus another type of treatment, changed from
moderate evidence (Level 2) that a lumbar support is not
more effective in reducing pain to conflicting evidence
(Level 3). The conclusion regarding the comparison of
lumbar supports versus no intervention did not change—
that is, there is limited evidence (Level 3) that a lumbar
support is more effective than no intervention.
383Lumbar Supports in Low Back Pain · Jellema et al
Discussion
Selection Bias
Despite the extensive search strategy used to identify all rele-
vant studies on the effectiveness of lumbar supports, some
studies may have been missed. The key words may not have
been in accordance with the key words used in the search
strategy of the present review, or the journals may have been
indexed in other databases. To find out whether there are
more trials published in nonindexed journals, the results of the
hand searching that is currently being performed within the
Cochrane Back Review Group are awaited.
Methodologic Quality
The two reviewers who assessed the methodologic quality
were not blinded to authors, journal, and institution. Po-
tential bias caused by the nonblinded quality assessment
was expected to be low. First, there was no conflict of in-
terest among the two reviewers—that is, the reviewers did
not have any (financial or other) interest in positive or neg-
ative results. Second, one reviewer (MWvT) is an expert in
the field of LBP and very familiar with the literature. Blind-
ing this reviewer did not seem feasible. The other reviewer
(PJ) was a layperson in the field of LBP. Blinding of such a
reviewer did not seem necessary, because that reviewer was
new to the field. Furthermore, the methodologic criteria
list, the operationalization of criteria, and the final results of
the assessment are presented, so readers can determine
whether they agree with the conclusions.
The methodologic quality was defined by the internal
validity criteria, which refer to characteristics of the
study that may be related to bias. The methodologic
quality of the studies included in the review was rather
low. Only 4 of the 13 studies scored positive on 50% or
more of the internal validity items and were considered
high quality.
17,24,37,41
Methodologic flaws that were
identified included the randomization procedure, the as-
sessment of cointerventions and compliance, and blind-
ing of patients and outcome assessors.
Although the authors of 11 studies stated that the
studies were designed to be randomized controlled trials,
an appropriate method of randomization and conceal-
ment of treatment allocation was described in only three
of the studies. Most studies did not report data on coin-
terventions or compliance. Van Poppel et al
37
and Red-
dell et al
31
reported low compliance. Compliance with
wearing lumbar supports is very important, because it is
impossible to find evidence for the effectiveness of lum-
bar supports if the subjects in a trial are not compliant
with wearing them.
34
Blinding of subjects is difficult in
trials on the effectiveness of lumbar supports. Only one
study succeeded in blinding the patients.
24
Even more
important is the blinding of the outcome assessor. How-
ever, in only 3 of the 13 studies was the use of a blinded
outcome assessor reported.
The validity, reliability, and responsiveness of out-
come measures were often not reported. Therefore, it is
unclear whether the instruments actually measured what
they were supposed to measure, whether they measured
with consistency, and whether they measured change
over time. Future studies should use valid, reliable, and
responsive instruments to evaluate the effectiveness of
preventive and therapeutic interventions.
Levels of Evidence
In this review, the authors refrained from statistical pool-
ing because of the heterogeneity of study populations,
control interventions, and outcome measures. The con-
clusions on the effectiveness of lumbar supports were
based on a qualitative analysis of the strength of scientific
evidence. The classification of the comparisons to a level
of evidence was sometimes arbitrary. When results of
several studies regarding a comparison did not entirely
agree with each other, it was difficult to decide whether
these results should be considered generally consistent
findings or inconsistent findings. For example, if all trials
were positive, it is obvious that the findings are consis-
tent, but are findings also consistent if five of seven trials
are positive or if four of seven are positive? The authors
arbitrarily defined consistency when 75% or more of the
studies had similar results. Extensive tables are presented
so that readers can determine whether they agree with
the classification of evidence in this review.
Effectiveness of Lumbar Supports
Seven preventive studies and six therapeutic studies were
included in this systematic review. The results of the sys-
tematic review showed that there is no strong evidence in
favor of or against the effectiveness of lumbar supports as
intervention for prevention and treatment. Even in the
sensitivity analyses, when the thresholds for high quality
were changed from 50% to 40% and when all unclear
scores were assumed to be positive, no strong evidence
could be demonstrated in favor of lumbar supports.
The results regarding prevention showed that there
was moderate evidence that lumbar supports are not ef-
fective in preventing LBP and that lumbar supports are
not more effective than other types of prevention for
LBP. The results of this review are in agreement with the
point of view of the National Institute for Occupational
Safety and Health (NIOSH) as presented in several re-
views.
6,14,19
According to NIOSH, the current literature
contains insufficient scientific evidence to support the use
of lumbar supports as a primary preventive measure. In a
systematic review, van Poppel et al
36
also reported in-
conclusive evidence in favor of or against the effective-
ness of lumbar supports for primary prevention.
Information regarding the possible secondary preventive
effects of lumbar supports was provided by subgroup anal-
yses in two studies.
37,41
The results of these subgroup anal-
yses indicated that workers with a history of LBP may be at
reduced risk for recurrent episodes of LBP. However, to
investigate the effectiveness of lumbar supports for second-
ary prevention, a randomized controlled trial focussing on
this question should be conducted.
The results regarding treatment showed that there
was conflicting evidence on the effectiveness of lumbar
supports compared with other types of treatment. Koes
384 Spine · Volume 26 · Number 4 · 2001
et al
20
concluded in their systematic review that the ef-
fectiveness of lumbar supports in the treatment of LBP
remains controversial. According to the available inter-
national guidelines for the management of LBP in pri-
mary care, a lumbar support should not be prescribed for
patients with acute LBP.
11
Limited evidence was found in favor of a lumbar sup-
port with a rigid insert in the back compared with a
lumbar support without rigid insert, indicating that some
types of lumbar supports may be more effective in reduc-
ing LBP than others. Most studies included in the review
did not provide detailed information about the type of
lumbar support that was used. The scarce information
showed that different types of lumbar supports probably
were used. In some reviews, investigators commented
that the type of lumbar supports that has been used in
controlled studies, such as those by Walsh and
Schwartz
41
and Reddell et al,
31
are not typically used or
recommended in industry. Because there are now more
than 70 types of lumbar supports for prevention
16
and
more than 30 types for treatment of spinal disorders in
use worldwide,
30
it would be interesting to know the
specific effects of different types of lumbar supports.
Conclusions
Implications for Practice
The findings in this systematic review did not provide evi-
dence that lumbar supports are or are not useful in the
primary prevention of low back pain in industry. The re-
sults showed that there is conflicting evidence on the effec-
tiveness of lumbar supports in the treatment of low back
pain. Lumbar supports are not recommended for primary
prevention and treatment of low back pain.
Implications for Research
Because none of the studies evaluated the effectiveness of
lumbar supports in the secondary prevention of low back
pain, future studies (if any) should focus on this topic.
Future trials should be of high quality, and special atten-
tion should be paid to adequate compliance of the study
subjects.
Key Points
●A systematic review of randomized and nonran-
domized controlled trials was performed.
●The effectiveness of lumbar supports for preven-
tion and treatment of nonspecific low back pain
was evaluated.
●There was moderate evidence that lumbar sup-
ports are not effective for primary prevention, and
no evidence on the effectiveness of lumbar supports
for secondary prevention.
●There was limited evidence that lumbar supports
are more effective than no treatment, whereas it is
still unclear whether lumbar supports are more ef-
fective than other interventions for treatment of
low back pain.
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Address reprint requests to
Maurits van Tulder, PhD
Institute for Research in Extramural Medicine
Vrije Universiteit, van der Boechorststraat 7
1081 BT Amsterdam, Netherlands
E-mail: mw.van_tulder.emgo@med.vu.nl
386 Spine · Volume 26 · Number 4 · 2001
