Posterior to anterior spinal stiffness measured in a sample of 127 secondary care low back pain patients

Understanding social determinants of health and physical therapy outcomes in patients with low back pain: A scoping review

BACKGROUND

Low back pain (LBP) is the number one cause of disability worldwide; however, it is not clear how social determinants of health (SDOH) impact care management and outcomes related to physical therapy (PT) services for patients with LBP.

OBJECTIVE

The purposes of this scoping review are to examine and assimilate the literature on how SDOH and PT care relate to non-specific LBP outcomes and identify gaps in the literature to target for future research.

METHODS

Data were extracted from eight electronic databases from January 2011 to February 2022. Reviewers independently screened all studies using the PRISMA extension for scoping review guidelines. Data related to study design, type of PT, type of non-specific LBP, patient demographics, PT intervention, SDOH, and PT outcomes were extracted from the articles.

RESULTS

A total of 30,523 studies were screened, with 1961 articles undergoing full text review. Ultimately, 76 articles were identified for inclusion. Sex and age were the most frequent SDOH examined (88% and 78% respectively) followed by education level (18%). Approximately half of the studies that examined age, sex, and education level identified no effect on outcomes. The number of studies examining other factors was small and the types of outcomes evaluated were variable, which limited the ability to pool results.

CONCLUSIONS

Sex and age were the most frequent SDOH examined followed by education level. Other factors were evaluated less frequently, making it difficult to draw conclusions. Study design and heterogeneity of determinants and outcomes were barriers to examining the potential impact on patients with LBP.

Low back pain and biomechanical characteristics of back muscles in firefighters

Firefighters often experience low back pain (LBP), but their back muscle characteristics are not well studied. This study aimed to 1) compare the biomechanical characteristics of back muscles and self-reported back disabilities in frontline firefighters with and without LBP history, and 2) examine the relationships between back disability and biomechanical measurements. We recruited 42 male firefighters and assessed their perceived pain and disabilities, maximum isometric back extension strength, passive stiffness, and fatigability of the longissimus. 54.8% of the participants experienced LBP within the past year. Those indicating higher pain intensity also had greater disability as indicated by the Oswestry Disability Index. There were no significant differences in strength, stiffness or fatigability of the back muscles between firefighters with and without LBP history. Multiple linear regression analysis revealed no significant relationship between the back disability and any biomechanical or demographic measures, likely due to the high functional abilities of the participants.

Defining and measuring objective and subjective spinal stiffness: a scoping review

PURPOSE

Examine and identify the breadth of definitions and measures of objective and subjective spinal stiffness in the literature, with a focus on clinical implications.

METHODS

A scoping review was conducted to determine what is known about definitions and measures of the specific term of spinal stiffness. Following the framework by Arksey and O'Malley, eligible peer-reviewed studies identified using PubMed, Ebsco health, and Scopus were included if they reported definitions or measures of spinal stiffness. Using a data abstraction form, the studies were classified into four themes: biomechanical, surgical, pathophysiological, and segmental spinal assessment. To identify similarities and differences between studies, sixteen categories were generated.

RESULTS

In total, 2426 records were identified, and 410 met the eligibility criteria. There were 350 measures (132 subjective; 218 objective measures) and 93 indicators of spinal stiffness. The majority of studies (n = 69%) did not define stiffness.

CONCLUSION

This review highlights the breadth of objective and subjective measures that are both clinically and methodologically diverse. There is no consensus regarding a standardised definition of stiffness in the reviewed literature.

A cross-sectional analysis of persistent low back pain, using correlations between lumbar stiffness, pressure pain threshold, and heat pain threshold

Introduction

Little is known about the underlying biomechanical cause of low back pain (LBP). Recently, technological advances have made it possible to quantify biomechanical and neurophysiological measurements, potentially relevant factors in understanding LBP etiology. However, few studies have explored the relation between these factors. This study aims to quantify the correlation between biomechanical and neurophysiological outcomes in non-specific LBP and examine whether these correlations differ when considered regionally vs. segmentally.

Methods

This is a secondary cross-sectional analysis of 132 participants with persistent non-specific LBP. Biomechanical data included spinal stiffness (global stiffness) measured by a rolling indenter. Neurophysiological data included pain sensitivity (pressure pain threshold and heat pain threshold) measured by a pressure algometer and a thermode. Correlations were tested using Pearson’s product-moment correlation or Spearman’s rank correlation as appropriate. The association between these outcomes and the segmental level was tested using ANOVA with post-hoc Tukey corrected comparisons.

Results

A moderate positive correlation was found between spinal stiffness and pressure pain threshold, i.e., high degrees of stiffness were associated with high pressure pain thresholds. The correlation between spinal stiffness and heat pain threshold was poor and not statistically significant. Aside from a statistically significant minor association between the lower and the upper lumbar segments and stiffness, no other segmental relation was shown.

Conclusions

The moderate correlation between spinal stiffness and mechanical pain sensitivity was the opposite of expected, meaning higher degrees of stiffness was associated with higher pressure pain thresholds. No clinically relevant segmental association existed.