Date Presented Accepted for AOTA INSPIRE 2021 but unable to be presented due to online event limitations.
OTs and other health care professionals frequently experience low back pain. This has been associated with multifidus cross-sectional area in various populations, but not previously in health care workers. This project observed multifidus cross-sectional area in OTs and other health care personnel. A pain group was compared with a nonpain group to assess differences between them. At the S1 level (with a trend at L5), those with more pain had smaller multifidus.
Primary Author and Speaker: Robert E. Larson
Contributing Authors: Ulrike H. Mitchell, A. Wayne Johnson
PURPOSE: Healthcare workers are among the most injured workers in the United States. Low back pain is a frequent complaint of occupational therapists and other healthcare workers. Multifidus muscle cross-sectional area in the low back has been found to be correlated with pain but this has not been observed in healthcare workers. Thus, there is a need to assess if multifidus cross-sectional area in this population correlates with low back pain to better understand the pain and strategize interventions to alleviate it in healthcare workers. This study investigates the issue of pain and its relationship to multifidus cross-sectional area in healthcare workers, including occupational therapists.
DESIGN: This study used a cross-sectional design observing the correlation between multifidus cross-sectional area and low back pain. Participants were 35 healthcare workers including occupational therapists, occupational therapy assistants, physical therapists, physical therapy assistants, nurses, and certified nursing assistants. Participants were recruited via word of mouth and promotional fliers. They were required to be within normal working years and ranged in age from 18-63. They were also required to work in inpatient, skilled nursing, or acute care settings. Those with pain (n = 18) and those without pain (n = 17) were included. Those who were pregnant were excluded from the study.
METHOD: The subject filled out a visual analog pain scale (VAS) to determine current low back pain level. One researcher collected and measured all of the ultrasound images for consistency. Images were taken using a GE LogiQ E ultrasound machine (GE Healthcare, Wisconsin, USA) equipped with a 4 MHz convex array transducer with the machine in musculoskeletal mode. The soundhead was positioned and the subject was instructed to raise the contralateral leg which engaged the multifidus muscle under observation. The subject then returned to a resting position and a retrospective cine-loop was recorded. This was completed twice for each muscle. These cine-loops were used to accurately determine the borders of the multifidus. This was repeated for all levels under scrutiny. The borders of the muscles were traced by a researcher (n = 1) using internal software on the same ultrasound machine and the cross-sectional area was procured. The two measurements of each muscle were averaged for a composite measurement for analysis.
RESULTS: There was a significant difference in multifidus cross-sectional area between those with pain and those without pain at the S1 level, a trend toward significance at L5, and no difference at L4. The mean cross-sectional area at S1 in the non-pain group was 10.2 cm2 which was larger than the pain group, which had an average of 8.49 cm2 (p = .0016). At L5 the values were 10.9 cm2 and 9.84 cm2 (p = .0180) and at L4 they were 10.6 cm2 and 9.88 cm2 (p = .0507) respectively. A Bonferroni correction was used to adjust alpha to 0.0167.
CONCLUSION: Healthcare workers with low back pain had significantly smaller multifidus cross-sectional areas at the S1 level. Similarly, at L5 and L4 those with pain had smaller multifidus, but not to a statistically significant degree. This shows that multifidus cross-sectional area is a possible factor in low back pain among occupational therapists and other healthcare workers. A follow up study involving rehabilitating these muscles and observing multifidus cross-sectional area and pain over time is warranted.
IMPACT STATEMENT: Occupational therapists and other healthcare workers can use this information to attempt to prevent and remediate low back pain with multifidus specific exercises. This will improve quality of life and potentially extend their healthy working life in their various professions.
References
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