Recommendations for terminology and the identification of neuropathic pain in people with spine-related leg pain. Outcomes from the NeuPSIG working group by Schmid, AB, Tampin, B, Baron, R, Finnerup, NB, Hansson, P, Hietaharju, A, Konstantinou, K, Lin, C-WC, Markman, J, Price, C, Smith, BH, Slater, H