ObjectiveTo explore the effectiveness of annular ligament reposition and repair via Henry’s approach for Monteggia fracture in children.MethodsA clinical data of 21 children with Monteggia fractures was retrospectively analysed, who underwent open reduction of the radial head and annular ligament reposition and repair via Henry’s approach between May 2015 and July 2019. There were 11 boys and 10 girls with an average age of 8 years and 1 month (range, 4 years and 5 months to 14 years and 4 months). The fracture was caused by falling in 17 cases and by falling from height in 4 cases. There were 16 fresh fractures and 5 old fractures. The Monteggia fractures were rated as Bado typeⅠin 14 cases and Bado type Ⅲ in 7 cases. Preoperative MRI examination and intraoperative observation confirmed that the annular ligament was intact. After operation, the fracture healing, elbow range of motion (ROM), and complications were recorded, and the effectiveness was evaluated according to the Mackay’s function scoring system.ResultsThe incisions healed by first intention after operation, and there was no complication such as radial nerve injury. All children were followed up 12-25 months, with an average of 15 months. No dislocation or subluxation of the radial head occurred after operation. At last follow-up, the ROM of elbow flexion and extension of the children with old fractures increased from (92.6±11.2)° before operation to (123.6±11.6)°, and the ROM of forearm rotation from (96.8±11.8)° to (129.8±5.9)°; the differences between pre- and post-operation were significant (t=7.672, P=0.002; t=9.487, P=0.001); the ROM of elbow flexion and extension of the children with fresh fractures was 139°-156° (mean, 145°); the ROM of forearm rotation was 158°-168° (mean, 162°). According to Mackay’s criteria, 17 cases were excellent and 4 cases were good, with an excellent and good rate of 100%. X-ray film examination showed no nonunion, heterotopic ossification, or loosening of internal fixation after operation. The ulnar fracture and the ulnar osteotomy healed in all cases.ConclusionThe annular ligament in Monteggia fractures in children is intact. Compared with the reconstruction of the annular ligament, the reposition and repair of the annular ligament via Henry’s approach is closer to the original anatomical state of the annular ligament and has the advantages of less trauma and fewer complications.