The interest of the Spanish network of investigators in back pain for rehabilitation physician by Arrebola, A, Kovacs, F, Gestoso, M, Vecchierini, N, Del Real Calvo, M, Pino, M, Castell, M, Ortega, J, Berstein, S, Burls, A, Villar, A, Kleinbaum, D, Sánchez, J, Herranz, A, Rodríguez, S, Gil, P, Santos, V, García, A, Zamora, J, Sánchez, D, Hernández, J, Pérez, J, Castillo, J, Torres, A, Mancebo, A