Original research
Relationship Between Radiographic Lumbosacral Spine Mensuration and Chronic Low Back Pain Intensity: A Cross-sectional Study

https://doi.org/10.1016/j.jcm.2017.10.005Get rights and content

Abstract

Objective

The purpose of this study was to investigate correlative factors affecting chronic low back pain (CLBP), with special emphasis on the radiographic postural findings in the sagittal lumbosacral spine.

Methods

A cross-sectional study alongside a randomized trial was conducted. Standing lateral lumbar spine radiographs from 352 patients with CLBP enrolled in a randomized trial were analyzed and radiographic mensuration of lumbar lordosis, lumbosacral disc angle, and sacral inclination performed. These angles were correlated with baseline variables, including CLBP intensity, age, and sex. Multiple polynomial regressions were performed in which CLBP intensity was regressed on linear and quadratic terms of lumbar lordosis to investigate the possibility of greater pain with hypo- and/or hyperlordosis.

Results

There was no significant correlation of the angles with pain and age (r ≤ 0.09, P > .05). Weak but statistically significant correlation was identified between all 3 measurements and sex (r = –0.12 to 0.21, P < .05). Greater pain was not noted for hypo- and hyperlordosis; regression coefficients for the linear and quadratic effects were approximately 0 (P > .05).

Conclusion

This study determined that there was no correlation between lumbar lordosis and pain levels for people with CLBP; thus, use of lumbar spine radiographic mensuration in the management of pain for people with CLBP is not recommended.

Introduction

Low back pain (LBP) is considered the single leading cause of professional and social disability worldwide.1 At least 70% of the population experiences low back pain at least once during their lifetime.2 Despite its socioeconomic impact and high prevalence,3 the etiology and understanding of the disease remain relatively enigmatic. Changes in the lumbar lordosis have been debated as a correlating factor in the production of LBP, with previous studies finding varying results.4, 5, 6, 7 Despite the differing conclusions regarding sagittal alignment of the lumbar spine and its association with LBP, clinicians continue to assess the lordosis and consider their findings when creating a treatment plan.

Historically, clinicians have noted a relationship between aberrations of lumbar spine posture and the development of low back pain.8 Abnormal posture causes straining of the highly innervated soft tissues, with tightening of the static postural muscles and weakening of dynamic musculature, thus indirectly altering the lumbar lordosis.9 Additionally, these habitual postural abnormalities lead to excessive shearing of the joints and eventually degeneration of the articular surfaces.8 Based on these findings, it has been speculated that deviation away from the “normal” lumbar lordosis plays a role in the production of low back pain.4 Consequently, the significance of radiographic mensuration of the lumbosacral spine used in practice requires further evaluation to see if it warrants a place in clinical practice.

In addition to aberrant posture, many factors have been suggested to play a role in the sagittal alignment of the lumbar spine. It has been proposed by previous authors that differences of the lordotic curve, as well as other sagittal lumbosacral measurements, including sacral inclination and the lumbosacral disc angle, may correlate with sex and age.5, 10, 11, 12 It is important to examine the effects of these particular factors as they partake in the patient-specific treatment.

Currently there is no general consensus on whether or not there is a relationship between low back pain and the sagittal lordosis of the lumbar spine.4, 5, 6, 7 The inconsistency of the findings could be due to error introduced by radiographic technique and mensuration as well as the sample participants. In addition, studies use a variety of methods to measure lordosis (eg, radiographs and flexible rulers), which may contribute to inconsistency. If radiographs are used, different techniques are used to measure lordosis. Furthermore, participants vary from study to study in sample size, sex, and age, all of which leave room for differences of findings. Studies with small sample sizes have been conducted with varied results.4, 6, 7, 12, 13 Hence, there has been a need to reevaluate the relationship between pain and posture using a larger sample size. The failure to agree suggests the need for further studies to investigate the relationship between low back pain and lordosis. Because clinicians continue to evaluate lumbar lordosis and other associated angles when forming a treatment plan for their patients, it is essential that their clinical significance, if any, be examined. The presence or absence of a correlation with pain will give preliminary evidence on the viability of the use of radiographic mensuration for the care of chronic LBP (CLBP).

The purpose of this study was to evaluate correlation between radiographic postural findings in the sagittal lumbosacral spine, including lumbar lordosis, lumbosacral disc angle, and sacral inclination posture and pain intensity for people with CLBP. The primary hypothesis was that the 3 angles are correlated with CLBP intensity, age, and sex, with emphasis on the relationship between lumbar lordosis and CLBP. A secondary hypothesis was a quadratic association between LBP and lumbar lordosis, such that greater pain would be noted at the higher and lower ends of the lordosis range.

Section snippets

Design

This was a secondary analysis utilizing baseline data and lumbar spine radiographs from a National Institutes of Health–funded randomized controlled trial by Haas et al14 using a cross-sectional design. The correlation of sagittal plane lumbosacral angles with participant characteristics was explored.

Participants

The study included 352 of the 400 original participants. They were required to have a current history of at least 3 consecutive months of nonspecific CLBP of mechanical origin. Participants were

Participant Characteristics

In a sample of 352 participants with at least 3 months of CLBP, there were 166 women (47%) and 186 men (53%). Their ages ranged from 18 to 81 with a mean age of 41.5 years (Table 1). The mean LBP intensity was 4.7 out of 10 (standard deviation = 1.7).

Lumbar Lordosis Angle

The range of lordosis was between 5° and 78° with a mean of 43.3 ± 11.0° (Table 1). The lordosis correlated poorly with average CLBP (r = 0.09) and was determined to not be statistically significant (P = .175) (Table 2). No notable linear or

Discussion

With respect to lumbar lordosis and CLBP, prior studies have varied greatly in their results.4, 5, 6, 7 In the present study, no statistically significant correlation was identified between the degree of lumbar lordosis and pain in a CLBP population. Our results agree with Hansson et al,6 who reported no relationship between lumbar lordosis and acute or CLBP. Additionally, in a 2001 study by Nourbakhsh et al,5 no difference was identified between normal participants and symptomatic patients in

Conclusions

This study determined that there was no correlation between lumbar lordosis and pain levels for people with CLBP. All of the sagittal lumbosacral radiographic measurements correlated poorly with pain and age. However, a weak, but statistically significant trend was identified between all 3 radiographic measurements and sex. Therefore, use of lumbar spine radiographic mensuration in the management of pain for people with CLBP is not recommended.

Funding Sources and Conflicts of Interest

Data were collected as part of a study funded by the National Center for Complementary and Integrative Health, National Institutes of Health (U01 AT001908). The contents of this publication are the sole responsibility of the authors and do not necessarily reflect the official views of the National Center for Complementary and Integrative Health. No conflicts of interests were reported for this study.

Contributorship Information

Concept development (provided idea for the research): S.K.S.

Design (planned the methods to generate the results): S.K.S., M.H.

Supervision (provided oversight, responsible for organization and implementation, writing of the manuscript): M.H.

Data collection/processing (responsible for experiments, patient management, organization, or reporting data): S.K.S.

Analysis/interpretation (responsible for statistical analysis, evaluation, and presentation of the results): M.H.

Literature search (performed

References (23)

  • MR Nourbakhsh et al.

    Effects of lifestyle and work-related physical activity on the degree of lumbar lordosis and chronic low back pain in a Middle East population

    J Spinal Disord

    (2001)
  • View full text