Comparison of two methods of percutaneous pin fixation in displaced supracondylar fractures of the humerus in children.

PURPOSE To conduct a prospective randomised controlled study to compare the stability and risk of nerve injury between fractures treated by medial-lateral pin fixation and those treated by 2-lateral pin fixation. METHODS Patients with displaced supracondylar fractures admitted between May 2000 and December 2001 were recruited into the study. They were randomised to treatment either with medial-lateral pin fixation (n=34) or with 2-lateral pin fixation (n=32). RESULTS 66 children with the mean age of 5.78 years were admitted during the study period. 11 of them were lost to follow-up. The mean follow-up period of the remaining 55 patients was 8.93 months. The difference in the carrying angle between injured and normal elbows was 3.57 degrees and 3.70 degrees in medial-lateral pin fixation and 2-lateral pin fixation, respectively. The extension and flexion loss was 7.14 degrees and 8.68 degrees respectively in medial-lateral pin fixation, and 7.11 degrees and 11.26 degrees respectively in 2-lateral pin fixation. The Baumann angle difference was 5.96 degrees in medial-lateral pin fixation, and 5.30 degrees in 2-lateral pin fixation. The difference in the medial epicondylar epiphyseal angle was 6.07 degrees in medial-lateral pin fixation and 6.92 degrees in 2-lateral pin fixation. Statistical analyses show that these differences are not significant. Five iatrogenic ulnar nerve injuries developed in the group treated by medial-lateral pin fixation, while 2 ulnar nerve and one radial nerve injuries were seen after 2-lateral pin fixation. Again the differences were not statistically significant. CONCLUSION Both methods of fixation were comparable in terms of stability, duration of bone healing, and risks of injury to the nerve.