It is important to understand potential complications of tibial tuberosity osteotomies (TTOs) and how to avoid them. TTO is associated with a 1% to 3% rate of tibial fracture and 1% rate of nonunion. Early weight-bearing and complete detachment of the distal tuberosity may increase these risks. Painful screws requiring removal occur in 3% to 77% of cases. Use of small (3.5- mm diameter), countersunk screws reduces this risk. Recurrent instability occurs in ∼5% of cases at 5 years. The risk of deep-vein thrombosis (4%) after TTO is higher than that associated with other sports surgeries (1% to 2%). The risk of wound complications is ∼1% and can be reduced with meticulous handling of soft tissues and avoidance of large medial incisions. The risk of deep infection is <1%. Severe complications such as compartment syndrome and pulmonary embolism are rare.