Tenon Medical Inc. has announced the publication of the second interim analysis from its ongoing MAINSAIL™ study. This study is a prospective, single-arm, multi-center, post-market clinical trial focused on evaluating the clinical and radiographic outcomes of the Catamaran® SI Joint Fusion System in treating sacroiliac $(SI)$ joint disruptions or degenerative sacroiliitis. The analysis reports on 24 consecutive patients from six U.S. clinical sites, assessing both primary and secondary clinical endpoints at the 12-month mark. Results showed statistically significant improvements in pain and disability, with mean VAS pain intensity scores decreasing from 78.8mm pre-operatively to 23.0mm, and ODI scores improving from 51.6% to 20.8%. Additionally, 83% of patients undergoing a 12-month radiographic CT follow-up demonstrated unequivocal evidence of fusion with bridging bone across the SI joint, as evaluated by an independent radiologist. These findings underscore the potential of the Catamaran SI Joint Fusion System in delivering consistent and reliable outcomes.