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Purpose The purpose of this study was to quantify diferences in mechanical stability of a wedge-shaped distalization tibial tubercle osteotomy (TTO) with a standard technique, versus a modiied technique with use of a proximal bone block and distally angled screw trajectory. Methods Ten fresh-frozen cadaver lower extremity specimens (ive matched pairs) were utilized. Within each specimen pair, one specimen was randomly assigned to undergo a standard distalization osteotomy ixed with two bicortical 4.5-mm screws oriented perpendicular to the long axis of the tibia, and the other to undergo a distalization osteotomy with modiied ixation utilizing a proximal bone block and distally angled screw trajectory. Each specimen's patella and tibia were mounted on a servo-hydraulic load frame using custom ixtures (MTS Instron). The patellar tendon was dynamically loaded to 400 N at a rate of 200 N/second for 500 cycles. Following the cyclic loading, loading to failure was done at 25 mm/min. ResultsThe modiied distalization TTO technique demonstrated signiicantly higher average load to failure compared to the standard distalization TTO technique (1339 N vs. 844.1 N, p < 0.001). Average maximum tibial tubercle displacement during cyclic loading was signiicantly smaller in the modiied TTO technique group compared to the standard TTO technique (1.1 mm vs. 4.7 mm, p < 0.001). Conclusion This study demonstrates that distalization TTO utilizing a modiied technique with a proximal bone block and distally aimed screws is biomechanically superior to standard distalization TTO without proximal bone block and screw trajectory perpendicular to the long axis of the tibia. This increased stability may aid in reducing the reported higher complication rates (including loss of ixation, delayed union and nonunion) following distalization TTO, although future clinical outcome studies are warranted.