Secondary hyperalgesia in chronic nonspecific low back pain

Abstract

Objective: Secondary hyperalgesia may be present in chronic nonspecific low back pain. The study compared pressure pain threshold (PPT) in the lumbar and thoracic paravertebral muscles in individuals with non-specific chronic low back pain correlating them with disability, functional mobility, age and body mass index. Method: This is a cross-sectional study involving individuals of both sexes diagnosed with non-specific chronic low back pain, aged between 18 and 65 years, with pain of moderate to severe intensity and with pain time of ≥ 12 weeks. The volunteers were evaluated for pain intensity through the Visual Analogue Scale (VAS), disability by the Roland Morris questionnaire, functional mobility by the Timed Up and Go test, and pressure pain threshold (PPT) by algometry. We used the t-test and made Pearson's correlation for data analysis that was done in the Graph Pad Instat program. Results: Fifty individuals (53.75 ± 13.65 years) participated in the study, and when comparing PPT values between the thoracic and lumbar regions, no significant difference was observed (p = 0.19). Moderate correlation was observed only between lumbar and thoracic PPT (r = 0.65). Other correlations, though some significant, were all weak. Conclusion: The data from this study allow us to conclude that individuals with chronic low back pain may present with secondary hyperalgesia, since the individuals presented similar values between the lumbar and thoracic PPTs, in addition to having a significant correlation between these two measures.

Relação da força muscular e limiar de tolerância de dor à pressão em pacientes com lombalgia crônica

“…Assim como o estudo de Imamura et al 14 um fator limitante foi a não avaliação de músculos da região lombar. Entretanto, em estudo prévio, 16 também não se observou correlação muito mais forte entre a incapacidade e o limiar de tolerância de dor à pressão da região lombar (r=-0,38).…”

“…Esta avaliação já foi usada em estudos com indivíduos com lombalgia crônica. 13,14,16 Para esta avaliação, foi analisado o LTDP do glúteo médio porção média, por ser este o ponto que mais se correlaciona com a dor em indivíduos com lombalgia. 14 Os pacientes foram posicionados em decúbito lateral, conforme já descrito por estudo anterior.…”