Affiliations: School of Physiotherapy, Royal College of Surgeons in Ireland, Dublin, Ireland | Maynooth Physiotherapy Clinic, Maynooth, Ireland | Curtin University, Western Australia
Abstract: Background: Nerve palpation is advocated as an examination technique for the identification of neural tissue involvement in lower limb pain disorders. Pressure algometry, used to determine pressure pain thresholds (PPTs), is a mechanical means of nerve palpation. This study investigated the PPTs of the sciatic, tibial and common peroneal nerves in asymptomatic subjects. Methods: A cross-sectional study design was used to investigate reliability and normative data of lower limb nerve palpation in asymptomatic subjects. An algometer was used to measure PPTs in 27 female and 12 male volunteer subjects. Measurements were taken twice by one examiner (intra-rater reliability) and once by a second examiner (inter-rater reliability). Results: Intraclass correlation coefficients for intra-rater reliability for the sciatic, tibial and common peroneal nerves were 0.83, 0.94 and 0.94 respectively, while those for inter-rater reliability were 0.86, 0.88 and 0.88 respectively. Mean PPTs and standard deviations for all three nerves on both sides in males and females are presented. There were no significant differences in mean PPTs between males and females for any of the tested sites (p>0.05). There was a significant difference in PPTs between sides at the sciatic (p=0.03) and tibial (p=0.03) sites, but not at the common peroneal site (p=0.15); these differences may have been due to an order effect. Conclusion: PPTs at the sciatic, tibial and common peroneal nerve sites tested demonstrated good to excellent intra-rater and inter-rater reliability. Normative values have also been documented.
Keywords: Pressure pain threshold, sciatic, tibial, common peroneal, nerve, reliability
