Paul S Sung1, Eric O'Sullivan2, Moon Soo Park3. 1. Department of Physical Therapy, Indiana Wesleyan University, Marion, Indiana, USA. paul.sung@indwes.edu. 2. Department of Computer Science, Central Michigan University, Mount Pleasant, Michigan, USA. 3. Department of Orthopaedic Surgery, Hallym University Dongtan Sacred Heart Hospital, Medical College of Hallym University, Hwaseong-si, Gyeonggi-do, Republic of Korea.
Abstract
PURPOSE: This study was conducted to investigate the reaction times and symmetry index (SI) of the bilateral trunk and limb muscles between control subjects and subjects with low back pain (LBP) that persisted for two months or longer. METHODS: Fifty-seven right limb dominant subjects (31 healthy control subjects and 26 subjects with LBP) participated in this study. The subjects were exposed to a slip perturbation (0.24 m/sec velocity for 1.20 cm), which caused them to move forward for 0.10 s in standing while holding a tray. The electromyography (EMG) electrodes were placed on the bilateral erector spinae (ES), rectus abdominis (RA), rectus femoris, hamstring, tibialis anterior, gastrocnemius, biceps brachii (BB), and triceps brachii muscles. The reaction times were analyzed, and the SI was used to compare the bilateral trunk and limb muscles for the degree of asymmetry between groups. RESULTS: The ES reaction time was significantly delayed in the control group (0.33 ± 0.22 vs. 0.22 ± 0.17; t = 2.25, p = 0.03). The SI of reaction times was significantly different on the RA (t = -2.28, p = 0.03), ES (t = -2.36, p = 0.04), and BB (t = -2.15, p = 0.04) muscles between groups. CONCLUSION: The delayed non-dominant ES reaction time might indicate a freedom of pain recurrence in the control group. Although the asymmetry increased on the RA and BB muscles in the LBP group, it decreased on the ES muscle. The asymmetries on the trunk and BB muscles were evident in the LBP group. The asymmetrical reactions in the arm-trunk muscles need to be considered for rehabilitation strategies.
PURPOSE: This study was conducted to investigate the reaction times and symmetry index (SI) of the bilateral trunk and limb muscles between control subjects and subjects with low back pain (LBP) that persisted for two months or longer. METHODS: Fifty-seven right limb dominant subjects (31 healthy control subjects and 26 subjects with LBP) participated in this study. The subjects were exposed to a slip perturbation (0.24 m/sec velocity for 1.20 cm), which caused them to move forward for 0.10 s in standing while holding a tray. The electromyography (EMG) electrodes were placed on the bilateral erector spinae (ES), rectus abdominis (RA), rectus femoris, hamstring, tibialis anterior, gastrocnemius, biceps brachii (BB), and triceps brachii muscles. The reaction times were analyzed, and the SI was used to compare the bilateral trunk and limb muscles for the degree of asymmetry between groups. RESULTS: The ES reaction time was significantly delayed in the control group (0.33 ± 0.22 vs. 0.22 ± 0.17; t = 2.25, p = 0.03). The SI of reaction times was significantly different on the RA (t = -2.28, p = 0.03), ES (t = -2.36, p = 0.04), and BB (t = -2.15, p = 0.04) muscles between groups. CONCLUSION: The delayed non-dominant ES reaction time might indicate a freedom of pain recurrence in the control group. Although the asymmetry increased on the RA and BB muscles in the LBP group, it decreased on the ES muscle. The asymmetries on the trunk and BB muscles were evident in the LBP group. The asymmetrical reactions in the arm-trunk muscles need to be considered for rehabilitation strategies.
Entities:
Keywords:
EMG; Limb dominance; Low back pain; Reaction times; Symmetry index
Authors: Trevor S Barss; Emily N Ainsley; Francisca C Claveria-Gonzalez; M John Luu; Dylan J Miller; Matheus J Wiest; David F Collins Journal: Arch Phys Med Rehabil Date: 2017-09-19 Impact factor: 3.966
Authors: Jacques Abboud; Arnaud Lardon; Frédéric Boivin; Claude Dugas; Martin Descarreaux Journal: Front Hum Neurosci Date: 2017-01-04 Impact factor: 3.169