Tehran University of Medical Sciences Journal of Orthopedic and Spine Trauma 2538-2330 8 3 2022 11 28 104 6 Reza Shahriar Kamrani Department of Orthopedic and Trauma Surgery, Shariati Hospital, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran Kian Zohrabi Department of Orthopedic Surgery, Shariati Hospital, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran 2022 02 23 2022 08 19 Background: Proximal humerus shortening and varus can occur secondary to neonatal shoulder septic arthritis and focal fibrocartilage dysplasia. Valgus osteotomy of the proximal humerus compensates for a little bite of shortening, and improves the shoulder joint's range of motion. Case Report: In this study, we present two patients with severe proximal humerus deformity following glenohumeral septic arthritis. Both of them underwent valgus osteotomy, and had a satisfactory result in terms of range of motions and cosmesis at five years follow-up. Conclusion: Treatment of varus deformity of proximal humerus is challenging issue. There are few reports of surgical treatment. Sever varus deformity of proximal humerus impacts the motion of shoulder. We reported a novel method of valgus osteotomy of proximal humerus in patients with severe varus deformity secondary to neonatal septic arthritis and long-term clinical follow-up. https://jost.tums.ac.ir/index.php/jost/article/view/368 https://jost.tums.ac.ir/index.php/jost/article/download/368/282