Objective To evaluate the therapeutic effect with peter-williams intramedullary nail on children with humerus deformity due to osteogenesis imperfecta.Methods Data of 9 patients with humerus deformity due to osteogenesis imperfecta were retrospectively analyzed from Jun.2009 to Dec.2012.There were 7 males and 2 females,aged from 6 years to 10 years and 7 months(average 8 years and 3 months).There were 7 unilateral humerus deformity and 2 bilateral humerus deformity with severe radius and ulna deformity.The humerus fracture frequency was from 4 to 13 times (average,7.9 times)There were 2-3 deformity points in 9 patients (average 2.09 deformity points).The deformity angle ranged from 20°-100° (average 57.3°).The Constant-Murley scores were 16-24 scores (average 20.44).According to revised Sillence classifications,there were 6 cases of Type Ⅲ and 3 cases of Type Ⅳ.Eleven humerus of 9 patients were osteotomied and fixed with peter-williams intramedullary nail.Results All of 9 children were followed up for 12-66 months(average 22 months).The bone healing time were 8-12 weeks (average 9.5 weeks).Parents of 9 children were satisfied with surgical operation effect and deformity correction.The Constant-Murley scores ranged from preoperative average of (20.44 ± 2.79) points (16-24 points) to postoperative average of (35.56 ± 2.60) points(30-38 points) at the latest follow-up of patients,there was a statistically significant in score before and after treatment(t =0.20,P ＜0.05).Number 4 patient,one patient was found suffering from dorsal thumb numbness postoperatively after 3 days back stretching limitation.Considering the radial nerve stretching injury,treatment with neurotrophic drug for 3 months,symptoms disappeared.There was no infection,or osteomyelitis,no vascular damages.Epiphyseal plate injury or premature closure and affecting growth were not found in all of the patients at the latest follow-up examination.Conclusions Treatment with osteotomy and peter-williams intramedullary nail fixation on children with humerus deformity due to osteogenesis imperfecta is advantaged.It gets less damages,no intruding shoulder joint,less bleeding.The greatest degree of correction of the deformity can be achieved,and the shoulder joint function and the quality of life can be improved.