Background: Articular depression, especially in central tibial plateau segments, is surgically challenging. According to the 10-segment classification, the anterolateral approach visualizes only 36.6% of the tibial plateau. The aim of this study was to compare biomechanical performance between fluoroscopy-guided fixation techniques with and without needle arthroscopy. Methods: This cadaveric study used 16 knee specimens with standardized lateral tibial plateau fractures. Specimens were randomized to fluoroscopy-guided (FG) or fluoroscopy plus needle arthroscopy-guided (FNG) reduction performed via an anterolateral approach. Kirschner wires and proximal tibial plates were used for fixation. The primary outcome was load to failure. Secondary outcomes included stress, strain, stiffness, reduction quality, radiation exposure, and operative time. Results: Sixteen cadaveric specimens (9 right knees; 12 males) were studied. The FG group had greater mean articular depression (1.77 versus 1.69 mm) and step-off (2.44 versus 2.26 mm) than the FNG group. The FNG group had a higher mean load to failure (1,784 versus 1,063 N), whereas the FG group had greater mean stiffness (170.34 versus 130.82 N/mm) and a longer mean operative time (1,662 versus 1,524 seconds). The FG group also demonstrated higher mean fluoroscopic doses and larger differences in condylar width and the medial tibial plateau angle than the FNG group. Conclusions: FNG reduction improved articular congruity and load to failure in lateral tibial plateau fractures without increasing operative time, supporting needle arthroscopy as a valuable adjunct for managing complex articular fractures with less invasive exposure. Clinical Relevance: This study is clinically relevant because it shows that incorporating needle arthroscopy during fixation of lateral tibial plateau fractures can improve reduction quality and stability without prolonging operative time.