Effects of situational and social factors on locomotor behavior in chronic non-specific low back pain patients walking through apertures.

Chronic non-specific low back pain (cNSLBP) is a leading cause of disability. However, its impact on daily activities (e.g., walking in public spaces) remains poorly understood. This study aimed to examine how cNSLBP individuals make navigation decisions when exposed to varying situational and social conditions. Eighteen cNSLBP (45.7 ± 9.2 years, 10 women) and eighteen asymptomatic adults (AA, 43.7 ± 9.5 years, 7 women) walked a 10-meter path to reach a goal and chose to pass between two apertures placed midway according to four conditions: (1) baseline: two large apertures, (2) situational: narrow and large apertures, (3) situational and social: human interferer facing the narrow or for (4) large aperture. Measures included switch point, walking speed, clearance distance, and pain perception. Results revealed that cNSLBP participants adopted more conservative decision-making strategies. Under situational and social conditions, they showed a marked preference for the larger aperture (switch points per conditions (1) 0.1; (2) 1.83; (3) 3.35, and (4) 3.34), with weaker modulation of their choices based on goal position (p < 0.01) than AA participants (switch points per conditions (1) 0.2; (2) 0.70; (3) 1.77, and (4) 2.15). While all individuals adapted their strategy in the presence of a human interferer, cNSLBP participants gave less consideration to social norms, with no difference between switch points for conditions 3 and 4. In terms of kinematics, cNSLBP participants walked significantly slower than AA, regardless of condition or goal position (p < 0.001). For both groups, clearance distance significantly increased for all trials involving a human interferer (p < 0.05). No significant differences were observed between groups or conditions in shoulder rotation or in trunk torsion (p > 0.05). This paradigm offers a promising approach to addressing cNSLBP-related functional impairments, though further research is needed to clarify the underlying mechanisms.