Feasibility of Physical Exam and Performance-Based Tests in Individuals With Chronic Low Back Pain: A Descriptive Study

Background

Despite the wide utilization of physical tests and pain assessments to evaluate individuals with chronic low back pain (cLBP), there is limited information about their feasibility in terms of test duration, the ability of individuals with cLBP to perform these tests, and associated adverse events. The literature also lacks reports on comprehensive characterization of physical tests to serve as a reference for clinicians and researchers. The objectives of the present work are to assess the feasibility of a comprehensive battery of physical tests and pain assessments germane to individuals with cLBP and characterize the tests' values in the context of a large cohort.

Methods

This cross-sectional analysis uses enrollment data from a large observational study conducted by the University of Pittsburgh Mechanistic Research Center—“Low Back Pain: Biological, Biomechanical, Behavioral Phenotypes (LB³P).” LB³P is part of the National Institutes of Health's Helping to End Addiction Long-term Initiative. Individuals with cLBP were screened by trained clinicians who assessed their safety to partake in up to 37 physical tests based on pre-existing medical conditions. Testers could elect not to administer tests based on their clinical judgment and participants could refuse to partake in tests. The reasons for not performing tests were recorded. The feasibility of the tests was assessed by the time to complete each test, percentages and reasons for tests not done, and adverse events related to test performance. Descriptive statistics for the physical tests were computed for the sample overall, and for the subgroups (male/female and age < 60/≥ 60) to serve as reference values for individuals with cLBP.

Results

The testing protocol took on average 130 min. In total, 8.9% of tests were not done. About one third of tests not done were screened out due to medical conditions identified during the safety screening, and two-thirds due to the tester's clinical judgment or participant refusal. Only four adverse events occurred, and they resolved without sequelae. The tests most often omitted were those requiring maximal and submaximal physical effort or could elevate blood pressure in those with hypertension, such as muscle strength testing of the hip, abdomen, and thigh, or hand immersion in cold water. From the 1007 participants enrolled in the study, those who did not complete one or more tests tended to be older, obese, less educated, and experienced more disability and back pain for a longer time. The descriptive statistics of the 37 tests are reported stratified by sex and age.

Conclusions

The results support the safety and feasibility of a comprehensive battery of physical tests and pain assessments in individuals with cLBP. This study also provides novel information on the test's performance frequency, reasons for not being completed, duration, and descriptive results in individuals with cLBP. This comprehensive characterization provides reference values for comparison in future research planning and clinical practice.