Mechanical behavior of nerve roots and pain mechanisms: insights and opportunities for advancement

Radiculopathy is a painful condition characterized by nerve root (NR) compression. NRs possess unique anatomical and biomechanical features, including the absence of protective layers, making them particularly vulnerable to deformation. This review aims to synthesize current knowledge of NR biomechanics, elucidate the mechanisms linking compressive loading to radicular pain, and identify literature gaps. A search of PubMed and Scopus was conducted with search terms targeting NR biomechanics and pain. Two reviewers independently screened 2658 titles, abstracts, and texts, identifying 53 studies that met the inclusion criteria. Current evidence underscores the role of mechanical stress in radiculopathy, with studies identifying compression thresholds that disrupt NR function. Key anatomical culprits include intervertebral discs, ligaments, and vertebrae. Research highlights the viscoelastic nature of NRs, which may amplify dysfunction under chronic loading and lead to ectopic firing and persistent pain. Despite these insights, considerable gaps remain in linking precise biomechanical thresholds to symptoms. Advancing this field requires further knowledge on nervous tissue mechanical properties. With further knowledge of tissue behavior, integration of state-of-the-art technology could explore the interplay of loading and NR responses. A deeper understanding of mechanisms could revolutionize diagnostics and offer tailored interventions to alleviate pain and improve patient outcomes.