Central Sensitization of Pain in Patients Presenting with Low Back Pain and Foot/Ankle Disorders

Abstract

Central sensitization of pain (CSP) is defined as the “increased responsiveness of nociceptive neurons in the central nervous system (CNS) to normal or subthreshold afferent input” The primary objective of this study is to compare the prevalence of CSP between patients presenting with foot and ankle conditions and those presenting with low back pain. Materials and Methods: A cross-sectional study was conducted comparing a cohort of patients with a first consultation for foot and ankle disorders to another cohort with a first consultation for lumbar spine pain at the same institution. Demographic variables, pain duration, main diagnosis, and a series of questionnaires assessing pain and disability were collected. The Central Sensitization Inventory (CSI) was administered to determine the presence of CSP within the groups. Statistical analyses were performed using STATA. Results: A total of 195 patients presenting with foot/ankle conditions and 252 patients with low back pain were included. Among the foot/ankle cohort, 16.4% (95% CI, 10.92–21.9%) were classified as having CSP, compared to 22.2% (95% CI, 16.85–27.6%) in the lumbar pain cohort. The difference in CSP prevalence between groups was not statistically significant (difference 5.79%, Chi2 = 2.357, p = 0.125). However, the difference in mean scores on Part A of the CSI was statistically significant (31.82 ± 13.88 vs. 25.20 ± 14.31, z = 4.237, p < 0.001). Among foot/ankle pathologies, plantar fasciitis showed the highest prevalence of CSP (21.9%), followed by hallux valgus (18.8%). A significant association was observed between CSP and higher levels of pain and disability. Female patients demonstrated a higher prevalence of CSP. Conclusions: Patients with low back pain exhibited higher CSI scores and a greater prevalence of central sensitization compared with those with foot and ankle disorders. Recognizing these mechanisms may help clinicians tailor more effective, multidisciplinary treatment strategies.