Changes in isokinetic trunk muscle strength and endurance after two different restoration programs in people with chronic low back pain: A longitudinal retrospective study

• Published in: Heliyon Vol. 10; no. 15; p. e34914
• Main Authors: Coleman, Marvin, Linières, Jonathan, Thery, Camille, Gautier, Adrien, Daste, Camille, Rannou, François, Nguyen, Christelle, Lefèvre-Colau, Marie-Martine, Rören, Alexandra
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 15.08.2024; Elsevier
• Subjects: Back muscles; Functional restoration program; Isokinetic; Life Sciences; Low back pain; Muscle strength; Isokinetic; Muscle strength; Back muscles; Low back pain; Functional restoration program
• ISSN: 2405-8440; 2405-8440
• DOI: 10.1016/j.heliyon.2024.e34914

Multidisciplinary functional restoration programs (FRPs) aim to improve pain and function in people with chronic low back pain (CLBP). The intensity and content of FRPs varies; the benefits of one program over another are unclear. To assess changes in trunk muscle strength and endurance after an intensive (IFRP) (for people on sick leave for >6 months with high levels of fear-avoidance beliefs about physical activity and work) or semi-intensive (SIFRP) (for people working) FRP in people with CLBP. Longitudinal retrospective study from March 2016 to December 2019. Setting: rehabilitation department of a tertiary care center. Trunk flexor and extensor muscle strength (60°.s−1) and endurance (120°.s−1) were measured with the Humac NORM isokinetic dynamometer at pre and post FRP. Change in isokinetic variables (peak torque, total work and flexor/extensor ratio) after each program was assessed with a paired t-test (p < 0.05). Pearson's rho and multiple linear regression assessed associations between changes in isokinetic and clinical variables and demographic characteristics. 125 individuals, 63.2 % female, age 43.5 (10.3) years, were included. Mean low back pain intensity was 49.8 (24.9) and 37.2 (25.8)/100 and mean activity limitation (QBPDS) was 38.8 (16.4) and 32.0 (14.6)/100 in the IFRP and SFRP groups, respectively. Trunk extensor peak torque, flexor total work, extensor total work and flexor/extensor peak ratio improved significantly in both FRPs, p < 0.001. The flexor/extensor total work ratio improved in the IFRP group only, p = 0.003. Trunk extensor endurance increased more in the IFRP than the SIFRP group, the absolute pre-post differences for extensor total work [95%CI] N.m were 611.7 [495.2; 728.3] in the IFRP group and 380.0 [300.8; 459.3] in the SIFRP group. No variables were correlated and none predicted improvement in extensor total work in either group. This study highlights the short-term independence of clinical and trunk muscle strength and endurance changes. •Trunk isokinetic strength and endurance significantly improved after both programs.•The intensive program showed greater improvement in trunk muscle endurance.•Changes in clinical and isokinetic variables were not significantly correlated.•No demographic or clinical data predicted extensor endurance improvement.