Safety and biological effectiveness of transforaminal (TLIF) and oblique lumbar interbody fusion (OLIF): a retrospective cohort study including patients with significant comorbidity. - Horvath-Szekely, Laszlo; Koch, Kristof; Nagy, Ildiko; Szita, Julia; Biczo, Adam; Jeszenszky, Dezso; Lazary, Aron (European Spine Journal, 2026)