BACKGROUND: Conservative treatment receives poor results in treating humeral intercondylar fractures,due to the over-long time fixation,and the recovery of joint function would be restricted.Early functional exercises should be based on stable internal fixation.OBJECTIVE: To explore the effectiveness of bone plate internal fixation in treating humeral intercondylar fractures under AO principle.METHODS: Totally 37 cases with humeral intercondylar fractures at the Department of Orthopaedics,Laibin People's Hospital from June 2000 to November 2005 were collected,under AO/ASIF classification,cases were assigned into three groups: type C1consisted of 11 cases,C2 consisted of 21 cases and C3 comprised 5 cases.All the cases were treated by olecranon osteotomy medial approach open reduction and then treated with dual anatomical plate internal fixation.Flexion and extension activities were done at 1 day after operation.Physical therapy was performed at 1 day after removing drainage.According to the images and clinical follow-up,slightly resistance exercise could be done at 4 weeks after operation,and gradually increased the load after8-12 weeks.RESULTS AND CONCLUSIONS: A total of 36 patients were included in the follow-up with 13-26 months,mean 19.5 months.All the bone fractures were recovered.Earlier operative reduction and exercise function would got better elbow joint recovery.All results demonstrated that dual anatomical plate treatment under AO principle provides firm internal fixation for patients with humeral intercondylar fractures,which is good for early exercise and functional recovery.