Background & Objectives: Musculoskeletal disorders are the main cause of occupational or work–related diseases. Occupational illnesses and especially chronic non–specific low back pain account for the majority of musculoskeletal disorders and cause long–term physical conditions and related treatments for the affected person. These individuals may even leave their jobs due to pain and illness. So this condition is very important. These diseases, due to their physiology, cause numerous problems, like pain and imbalance in the affected patients, resulting in increased healthcare costs and declined quality of life. Therapeutic exercise interventions in people with chronic non–specific back pain can be effective to a great extent, and for this purpose, various exercise programs have been proposed. However, some contradictory results are also observed in previous research investigating the effect of core stability exercises on patients with chronic low back pain. Accordingly, the present study aimed to investigate the effect of a stable weekly exercise program on static and dynamic balance in patients with chronic non–specific low back pain.
Methods: The present quasi–experimental study was conducted on 40 medical staff with low back pain working at Shariati Hospital in Isfahan City, Iran. The study subjects were randomly divided into two groups of control and intervention (each group of 20 subjects). The control group performed the routine exercises and the intervention group performed the stability training for 8 weeks. Before and after the intervention, the static and dynamic balance of the patients was measured by the Balance Error Scoring System (BESS) and Star Balance Test. In the BESS, the static balance of each subject on two stable and unstable surfaces was assessed. Moreover, they were evaluated in three physical states, including a standing position on two legs, standing on one leg with 90–degree knee flexion, and the tandem stance with non–dominant foot behind dominant foot in heel–toe fashion, with closed eyes and hands on hips. Additionally, each situation was preserved for 20 seconds. The subject receive 1 negative score for each of these mistakes: opening the eyes, removing the hands from the hips, laying the foot at the time of standing on one leg on the ground, stepping leakage or any movement of the legs, lifting the toe or heel, a flexion or abduction of>30 degrees in the pelvis, and staying>5 seconds. Also, a standard RA was recorded in the off–state. The star test (dynamic balance) was performed 8 times for each subject in 8 directions, as follows: anterior, anterolateral, anteromedial, posterior, medial, posteromedial, posterolateral and lateral. In this test, 8 directions with a 45–degree angle were drawn as a star on the ground. Before initiating the test, the dominant leg of the study subject was determined; if the right leg were dominant, the test would have been performed in the clockwise direction, and if the left leg were dominant, the test would have been performed in a counterclockwise direction. The obtained data were analyzed by the t–test, Chi–squared test, Wilcoxon test, and Mann–Whitney U test at a significance level of 0.05 in SPSS version 23 software.
Results: The results showed that, in the examination of dynamic balance, in the core stability group, significant progress was made in the anterior (p=0.001), anteromedial (p=0.001), medial (p<0.001), posteromedial (p=0.001), posterior (p<0.001), posterolateral (p<0.001), lateral (p<0.001), anterolateral (p<0.001) and the combination of eight directions (p=0.011), after eight weeks of general exercises. However, in the control group, no significant improvement was observed in the anterior, anteromedial, medial, posteromedial, posterior, posterolateral, and lateral before and after eight weeks of general exercises (p>0.05). Nevertheless, there was a significant decrease in anterolateral direction (p=0.016). In the analysis of static balance, in the core stability group, a significant improvement was achieved in different situations of unstable level (p=0.001) and stable level (p=0.008). However, no significant progress was observed for the control group in different situations of unstable level and stable levels (p>0.05).
Conclusion: Based on the present study’s findings, the core stability training intervention affected the static and dynamic balance of medical personnel suffering from chronic non–specific back pain and improved the physical performance of these patients.