Avulsion fractures of the tibial tuberosity are commonly sustained in adolescent males during sport activities which involve jumping and tackling. Tibial tuberosity avulsions combined with lateral tibial plateau in an adolescent are rare injuries. We received an unusual case of left Ogden type IIIB avulsion fracture of the tibial tuberosity with an articular involvement of the lateral tibial plateau (Salter Harris type IV) in a 14-year-old boy. The injury was sustained after jumping from three stairs where the boy predominantly landed on his left lower limb. Unlike other cases reported, since they were athletes and injuries were sustained during sport activities, our case is an obese individual who jumped off few stairs. The results following surgical treatment are excellent since the fracture united, and the articular surface was restored without the need of arthrotomy with gaining full range of motion. Therefore, displaying this case in the literature will be helpful since it is rare and was successfully treated differently from the previously reported cases.