Comparison of postural sway and duration of the stance phase of gait between male low back pain developers and non-pain developers aged 18 to 30 years

Being prone to Low Back Pain (LBP) development is a concept in the field of back pain prevention. Those prone to develop LBP show differences in motor control patterns compared to those who are not. Therefore, the present study aimed to compare postural sway and duration of the stance phase of gait between 18-30 years old men prone to LBP and non-prone to LBP.

The current study was observational and comparative. The statistical population comprised all the students living in the University of Tehran dormitory. Of whom, 33 individuals were selected purposefully based on inclusion and exclusion criteria. The inclusion criteria were as follows: being 18-30 years old men; having body mass index of 18-30 kg/m2; not working in a job in the last 12 months that required prolonged standing, lacking apparent musculoskeletal disorders in the trunk, upper and lower limbs; lacking any visual, vestibular, nervous, muscular, or pain problems affecting the balance; lacking LBP that causes any of the following outcomes: receiving medical interventions, absence of work for more than 3 days, and surgery in the waist, pelvis, and lower limbs. The exclusion criteria were as follows: report of low back pain at the beginning of long standing protocol, not able to complete the study questionnaire, score more than 13 in the Baecke physical activity questionnaire, score more than 13 in Borg scale (almost heavy work), and reluctant to finish the test. The study participants were divided into two groups: prone to develop low back pain (16 patients) and non-prone to develop LBP (17 patients) by performing active hip abduction test and reporting their pain based on the visual analog scale during the prolonged standing protocol. Postural sway and duration of the stance phase of gait were measured using the Biodex balance system and Foot Medisense device. Data analysis was done using the independent t test and Mann-Whitney U test in SPSS version 28 software, at a significance level of α=0.05.

The results showed no significant difference between the prone to LBP group and the non-prone group regarding the anterior-posterior stability index, the medial-lateral stability index, and the overall stability index( in both static and dynamic positions for all indexes) and duration of the stance phase of gait between low back pain developers and non-pain developers.

It seems that people prone to develop LBP do not experience any changes in postural sway and duration of stance phase of gait before the onset of low back pain, and these variables may not be able to help identify those who are prone to develop low back pain.