Chronic low back pain (CLBP) is a very common symptom experienced by people of all ages and is considered the leading cause of disability in the world. Its global prevalence is 7.3%, that is, 540 million people are affected by the condition, with an increase of 54% since 1990. In some studies, the prevalence of CLBP was higher in women (60.9%) than in in men (39.1%). Most recommended treatments for CLBP (with moderate and high evidence) have small effects, including pharmacological solutions such as the use of opioids. Among the available treatments, manipulative therapy is one of the possibilities, as they have hypoalgesia effects similar to those observed for other therapies recommended by guidelines. In the present study, we evaluated whether there is a difference in pain intensity between men and women before and after manipulative therapy using the Numerical Pain Rating Scale.

To identify if the is a difference in pain intensity between men and women with CLBP after a manipulative therapy session.

this is a cross-sectional and secondary study based on data from a randomized clinical trial that offers manipulative therapy as a treatment for patients with CLBP. At the first meeting, the patients were evaluated regarding: sociodemographic aspects such as sex, age, weight, height, income, and education; pain intensity.

So far, 128 patients with non-specific CLBP have participated in this study, totaling 64 females and 64 males. The average age of the male (M) sample was 44 years (SD=9.49) and female (F) 45.5 years (SD=8.78), with an average weight of M=87 kg (SD=15.68) and F=76.5 kg (14.49), average height of M=178.5 cm (SD=23.15) F=162 cm (SD=5.97). All data were tested for normality using the Shapiro-Wilk test. An analysis of variance (ANOVA) of repetitive measures was applied. The intra- and between-subject factors were time (period before and after 1 session of manipulative therapy) and Group (men and women), respectively. The post-hoc test using the Bonferroni correction was used when a significant interaction was found.

There was no interaction between gender and pain intensity after a manipulative therapy session. Both sexes showed significant improvement after a manual therapy session (P<0.05). Among men, 32 subjects showed clinically significant improvement in reducing pain intensity. Among women, this number was 39 people.

These results bring information about the characteristics of the sample.