Pressure pain thresholds in office workers with chronic neck pain: A systematic review and meta-analysis

Abstract Objectives 1) Compare pressure pain threshold (PPT) values between office workers with chronic neck pain and asymptomatic controls; 2) establish reference PPT values in chronic neck pain; 3) evaluate associations between PPTs, pain intensity and disability. Methods Seven English/Portuguese databases were searched for relevant literature. Studies investigating adult office workers (age >18) with chronic neck pain were included if PPTs were an outcome. The risk of bias was assessed using the Downs and Black checklist. Meta-analysis was conducted if a cluster contained at least two studies reporting the same PPTs. Results Ten high quality, two low quality, and one poor quality studies were included. The meta-analysis revealed decreased PPT values in the upper trapezius, extensor carpi ulnaris, and tibialis anterior in chronic neck pain workers when compared with healthy workers, without a statistical difference (p>0.05). The PPT reference value in the upper trapezius was 263 kPa (95 236.35, 289.70), and 365 kPa (95 316.66, 415.12) for the tibialis anterior in office workers with chronic neck pain. No correlations were found between the upper trapezius PPT and pain intensity and disability. Conclusion This meta-analysis found that all the pressure pain threshold measurements were not significantly reduced in office workers with chronic neck pain compared with healthy workers. These assumptions were based on a small sample of existing studies, and therefore further studies are necessary to quantify the differences in pressure pain thresholds. Hypersensitivity PPT reference values are proposed for localized and extra-segmental sites in office workers with chronic neck pain.