Low Back Pain & Sciatica, a brief epidemiological introduction and review of 2 articles with conflicting findings addressing the prognostic factors and outcome.
3. • Low back pain is one of the most common health problems and creates a
substantial personal, community, and financial burden globally.
• LBP is a major cause of disability - affecting performance at work and
general well-being.
• LBP affects people of all ages, from children to the elderly, and is a very
frequent reason for medical consultations.
• The 2010 Global Burden of Disease Study estimated that LBP is among the
top 10 diseases and injuries that account for the highest number of DALYs
worldwide.
4. Disability-Adjusted Life Year (DALY)??
• One DALY one lost year of "healthy" life measurement of
the gap between current health status and an ideal health situation.
DALYs for a disease or health condition are sum of the Years of Life Lost
(YLL) due to premature mortality and the Years Lost due to Disability
(YLD) for people living with the health condition in a population.
6. Prevalence:
• The lifetime prevalence of non-specific LBP is estimated at 60% to 70% in
industrialized countries (one-year prevalence 15% to 45%, adult incidence 5%
per year).
(Over 70% of people in resource-rich countries develop LBP at some time)
• The prevalence rate for children and adolescents is lower than that seen in
adults but is rising.
• Prevalence peaks between the ages of 35 and 55
7. • In the United Kingdom, low back pain was identified as the most
common cause of disability in young adults, with more than 100
million workdays lost per year
• In Sweden, a survey suggested that low back pain accounted for a
quadrupling of the number of work days lost from 7 million in 1980 to
28 million by 1987.
8. LBP in USA
• Episodes of LBP, that are frequent or persistent have been reported in
15% of the US population.
• Lifetime prevalence of 65% to 80%.
• 28% of the US industrial population will experience disabling LBP at some
time & 8% of the entire working population will be disabled in any given
year, contributing to 40% of all lost work days.
• Morbidity & mortality of occupational injury or illnesses in the US
showed that the total direct costs ($65 billion) plus indirect costs ($106
billion) were estimated to be $171 billion, with injuries costing $145
billion and illnesses $26 Billion.
9. Low back pain ranks No. 1 in musculoskeletal disorders.
Modified and adapted from Lawrence and colleagues
10. Risk Factors
• age
• Genetic
• Gender ???
• obesity, body height
• occupational posture
• frequent bending, twisting
• heavy physical work
• Whole body vibration
• depressive moods
11. II – Topic Articles Review:
Haugen, A. J., Brox, J. I., Grøvle, L., Keller, A., Natvig, B., Soldal, D., &
Grotle, M. (January 01, 2012). Prognostic factors for non-success in
patients with sciatica and disc herniation. Bmc Musculoskeletal Disorders,
13.
Peul, W. C., Brand, R., Thomeer, R. T., & Koes, B. W. (January 01, 2008).
Influence of gender and other prognostic factors on outcome of sciatica.
Pain, 138, 1, 180-91.
12. Haugen et al., Prognostic factors for non-success in
patients with sciatica and disc herniation – Study (1)
• Study Design: Prospective multicenter Cohort study.
• Main Variables measured:
1- socio-demographic characteristics
2- back pain history
3- kinesiophobia
4- emotional distress
5- pain
6- comorbidity
7- clinical examination findings.
13. • Cohort Selection and Recruitment:
1- Patients were recruited from specialty back clinics at 4 public
hospitals in Southeast Norway.
2- inclusion period was 2 years, throughout 2005 and 2006.
• Inclusion criteria:
i. age ≥18 years
ii. radiating pain and/or paresis below knee level
iii. disc herniation at the corresponding level and side that had been
verified by (MRI) or (CT).
14. • Exclusion criteria:
i. Prior surgery at the same disc level.
ii. Fracture
iii. Infection
iv. Malignancy
v. Pregnancy
vi. Lack of fluency in Norwegian.
15. • Procedure:
At the day of inclusion patients completed a comprehensive
questionnaire. Baseline data were collected at the first visit to the
department. Clinical examination was conducted by a physician or
physiotherapist. A follow-up questionnaire and a prepaid envelope
were sent to the patients after 3, 6,12 and 24 months. A reminder
was sent after 2 weeks if no reply was obtained.
In each questionnaire, the participants were asked whether they had
undergone surgery for disc herniation in the period since the last
follow-up period, and if so, the patient reported the date of surgery.
16. Outcome measure and definition of non-success
1- Maine–Seattle Back Questionnaire (MSBQ) was the main outcome
measure.
• The scale is composed of 12 items
• each with the answer yes (1) or no (0).
• The MSBQ assesses disability and functional limits due to sciatic and
back pain, and higher scores indicate worse limitations on activity.
• Non-success was defined as a MSBQ score ≥ 5
17. 2- Siatica Bothersomeness Index (SBI) is the secondary outcome
measure was the Sciatica.
• SBI is a composite of the scores for four symptoms: leg pain (sciatica);
numbness or tingling in the leg, foot or groin; weakness in the leg or
foot; and back or leg pain while sitting.
• Nonsuccess was defined as a SBI score of ≥ 7
18. Outcomes:
466 patients were included.
409 (88%) responded to the 1-year follow-up questionnaire.
380 (82%) responded to the 2-year follow-up questionnaire.
Among the responders at 1 year, 120 (29%) had received surgical
treatment.
At 2 years, 120 (32%) of the responders were recorded as surgically
treated.
For patients who were operated, surgery was performed within 3
months of follow-up for 81% of the patients.
Patients with non-success (MSBQ ≥ 5) numbered 178 patients (44%)
at 1 year and 145 (39%) at 2 years.
19. Outcomes (Cont’d):
the surgically treated patients, 42 (35%) had non-success at the 1-
year follow-up, and 47 (39%) had non-success at the 2-year follow-up.
the non-surgical group, 136 (47%) and 98 (39%) patients had non-success
at 1 and 2 years respectively.
20. Results:
1) 44%–47% of the patients with sciatica who were referred for
secondary care had a non-successful outcome at 1 year and 39%–
42% at 2 years.
2) Approximately 1/3 of the patients were treated surgically.
3) For the main outcome variable, non-success at 1 year was
significantly associated with being male (OR 1.70 [95% CI; [1.06 −
2.73]), smoker (2.06 [1.31 − 3.25]), more back pain (1.0 [1.01 −
1.02]), more comorbid subjective health complaints (1.09 [1.03 −
1.15]), reduced tendon reflex (1.62 [1.03 − 2.56]), and not treated
surgically (2.97 [1.75 − 5.04]).
21. 4) factors significantly associated with non-success at 2 years were
duration of back problems > 1 year (1.92 [1.11 − 3.32]), duration of
sciatica > 3 months (2.30 [1.40 − 3.80]), more comorbid subjective health
complaints (1.10 [1.03 − 1.17]) and kinesiophobia (1.04 [1.00 − 1.08]).
5) For the secondary outcome variable, more comorbid subjective health
complaints, more back pain, muscular weakness at clinical examination,
and not treated surgically, were independent prognostic factors for non-success
at both 1 and 2 years.
22. Peul et al., Influence of gender and other prognostic
factors on outcome of sciatica Study (2):
• Research Question:
• Female gender has been found to be associated with chronic pain in
other musculoskeletal disorders.
• The study aim is to quantify the relationship between gender and
(1) rate of recovery
(2) outcome at one year
23. Design:
• Randomized Multicenter Trial
• Patients were allocated randomly to either a prolonged conservative care,
possibly with late surgery, or early surgery preferably within two weeks.
Inclusion Criteria:
• 283 patients who suffered sever sciatica were enrolled
• age 18 – 65 years old
• had a radiologically confirmed disk herniation
• incapacitating lumbosacral radicular syndrome lasting between 6 and 12
weeks
24. Exclusion Criteria:
1. cauda equina syndrome
2. muscle paralysis or insufficient strength to move against gravity
3. Patients had had identical complaints in the past twelve months
4. history of spinal surgery
5. bony stenosis
6. Pregnancy
7. severe comorbidity
25. Outcomes:
• Follow-up of patients at 2, 4, 8, 12, 26, 38 weeks and at one year was
recorded.
• A 7-point Likert global perceived recovery scale, patient experienced
recovery compared to baseline, with answers ranging from
completely recovered to much worse.
• Roland Disability Questionnaire (RDQ) for Sciatica
• Horizontal Visual Analogue Scale (VAS-leg) recording the individually
experienced intensity of pain
26. Results:
• Allocation of an early surgical strategy resulted in 125 of 141 (89%)
patients who actually underwent lumbar discectomy after a median
period of 1.9 weeks.
• while of the 142 conservatively managed patients surgery could not
be avoided in 55 (39%) after a median time of 14.6 weeks.
• At different follow-up moments during the first year 269 of 283 (95%)
patients registered complete recovery.
• At exactly 12 months, however, 83% of patients reported complete
recovery
• (34%) of 283 patients were female.
27. Results (Cont’d):
• Results at 12 months showed a significantly different outcome
between genders with 28% of females exhibiting an unsatisfactory
perceived outcome versus 11% of males??
• Women had a slower rate of recovery: HR 0.76 (95% CI 0.59–0.99)
with an unsatisfactory outcome represented by an unadjusted odds
ratio of 3.3 (95% CI 1.7–6.3) compared to males. Besides a slower
recovery rate, female gender was a strong predictor of unsatisfactory
outcome at one year for patients with sciatica
28. Conflicting Findings
Haugen et al.,
• Non-Success 44%–47% at One
Year, 39%–42% at 2 years.
• Non-success at 1 year was
significantly associated with
being male (OR 1.70) .
Peul et al.,
• (95%) patients registered
complete recovery, at 12 months
(83%) of patients reported
complete recovery.
• Women had unsatisfactory
outcome represented by an
unadjusted (OR 3.3)compared
to males.
29. Discussion & possible explanation of
conflicting findings:
• The 2 studies had different Designs, Haugen et al Prospective Cohort,
Peul et al Randomized Trial, randomization procedure wasn’t stated
in the article.
• Haugen et al enrolled 466 participants, Peul et al enrolled 283
participants (Bigger sample size in Haugen et al more precision in
results?)
• Haugen et al Followed patients for 2 years, Peul et al followed
patients for 1 year (Longer time of follow up, better assessment of
association between predictor variables & outcome variables).
30. • Exclusion Criteria in Peul et al were duration of sciatica symptoms of more
than 12 weeks, similar complaints during the previous year, or severe
comorbidity, therefore Haugen et al was probably more representative of
the majority of patients with sciatica and disc herniation.
• Haugen et al used the most precise outcome measures, which in a previous
study showed the highest sensitivity and specificity to discriminate
between successful outcome or not for sciatica patients.
• Haugen et al had a broader range of prognostic variables including several
clinical findings, psychological variables and comorbid subjective health
complaints.
• The success rates and prognoses for sciatica vary between studies,
depending on the inclusion criteria and outcome measures used.
31. Refrences:
1. Haugen, A. J., Brox, J. I., Grøvle, L., Keller, A., Natvig, B., Soldal, D., & Grotle, M.
(January 01, 2012). Prognostic factors for non-success in patients with sciatica
and disc herniation. Bmc Musculoskeletal Disorders, 13.
2. Peul, W. C., Brand, R., Thomeer, R. T., & Koes, B. W. (January 01, 2008).
Influence of gender and other prognostic factors on outcome of sciatica. Pain,
138, 1, 180-91.
3. Hall, Hamilton, & McIntosh, Greg. (n.d.). Low back pain (chronic). BMJ
Publishing Group.
4. Manchikanti, Laxmaiah, et, al. “Epidemiology of Low Back Pain”. Pain Physician
Vol. 3, No. 2, 2000.
5. Duthey, Béatrice. “Background Paper 6.24 - Low back pain”. Priority Medicines
for Europe and the World "A Public Health Approach to Innovation“ Update on
2004 Background Paper (15 March 2013). WHO.