ObjectiveTo investigate the effectiveness of three-dimensional (3D) navigation template in the adult cubitus varus osteotomy.MethodsBetween April 2013 and September 2015, 17 patients with cubitus varus were admitted. There were 6 males and 11 females, aged from 19 to 38 years, with an average age of 26.9 years. There were 10 cases of left elbow joints and 7 cases of right elbow joints. The disease duration was 9-30 years (mean, 18 years). Based on the preoperative X-ray film, the humerus-elbow-wrist (HEW) angle was (−13.2 ±3.3)°, the anteversion angle was (−10.5±2.3)°. The preoperative range of motion (ROM) of flexion was (127.3±7.3)° and ROM of extension was (−10.0±2.5)°. Based on the CT 3D reconstruction, the osteotomy navigation template was designed and printed by 3D printing technique. The cubitus varus osteotomy was assisted by 3D navigation template. The postoperative HEW angle, anteversion angle, and ROMs of the elbow joints of both sides were measured. The elbow function was evaluated based on the Oppenheim elbow function score at 1 year after operation.ResultsAll cubitus varus osteotomies succeeded with the assist of 3D navigation template. All incisions healed by first intention. All patients were followed up 12-15 months (mean, 13 months). X-ray films showed that all osteotomies healed after 9-12 weeks (mean, 11 weeks). At 1 year after operation, the HEW angle was (9.7±1.9)°, the anteversion angle was (20.7±4.3)°, the ROM was (2.6±3.5)° in extension and (139.2±4.8)° in flexion of affected side. The HEW angle, anteversion angle, and ROMs significantly increased compared with preoperative values (P<0.05). And there was no significant difference between affected and normal elbow joints (P>0.05). The elbow functions were excellent in 13 cases and good in 4 cases based on the Oppenheim elbow function score at 1 year after operation. There was no complication such as the nerve injury or osteomyositis of elbow joint during follow-up. ConclusionThe 3D navigation template can provide a personalized and precise osteotomy treatment for adult cubitus varus deformity and obtain a satisfactory effectiveness.