Abstract Objective:Proximal Junctional Failure (PJF) is a known complication of instrumented spine surgery. When a construct ends in the lower thoracic spine, PJF occurring at the suprajacent level can be difficult to adequately correct. Transforaminal Thoracic Interbody Fusion (TTIF) is a posterior-only pedicle-sparring approach that may offer effective correction of thoracic PJF.Methods:This report details a single-center retrospective review of patients who underwent TTIF for PJF correction from 2014-2020. Demographic data, operative details, and Oswestry Disability Index (ODI) was included for all patients with at least 1 year follow-up. Preoperative and postoperative full-spine radiographs were assessed for correction of proximal junctional kyphosis (PJK). Surgical complications were recorded.Results:A total of 22 patients underwent TTIF for PJF correction. Average kyphosis correction was 15° ± 10° (range 0° - 40°). All patients achieved correction to their physiologic sagittal alignment goals, except for one patient that experienced neuromonitoring changes during correction. All cases demonstrated arthrodesis. Mean ODI improvement at 1 year was 12.2% ± 20.0% (range -18.0% - 54.7%; p=0.048).Conclusions:TTIF is a viable and technically reproducible posterior-only approach for the surgical correction of thoracic PJF.