[Case-control study on the occurrence of cubitus varus deformity after humeral supracondylar fractures treated with plaster fixation in pronated or supinated position in children].

OBJECTIVE

To retrospectively compare the occurrence of cubitus varus deformity after humeral supracondylar fractures treated with manipulative reduction and plaster fixation in pronated or supinated position in children, and to guide clinical treatment.

METHODS

From June 2009 to December 2011, the medical data of 64 children with humeral supracondylar fractures treated by manipulative reduction and plaster fixation were reviewed. All the patients were divided into two groups: group A and group B. The 30 patients in group A were treated with manipulative reduction and plaster fixation in pronation, including 18 males and 12 females, with a mean age of (7.5 ± 3.5) years old. The 34 patients in group B were treated with manipulative reduction and plaster fixation in supination, including 23 males and 11 females, with a mean age of (7.0 ± 2.6) years old. The occurrence rates of cubitus varus and decreases of carrying angle were compared between two groups before and after treatment.

RESULTS

There were 13 patients in group A and 16 patients in group B having cubitus varus,which had no statistical difference (χ2 = 0.089, P = 0.765). The decrease of carrying angle were (8 ± 4) degrees in group A and (9 ± 5) degrees in group B, which had no statistical difference (t = 0.584, P = 0.564). Within group A, the occurrence rate of cubitus varus and the decrease of carrying angle between the radial deviation and the ulnar deviation had statistically significant difference (χ2 = 6.160, P = 0.013; t = - 2.409, P = 0.035). Within group B, the occurrence rate of cubitus varus and the decrease of carrying angle between the radial deviation and the ulnar deviation had statistically significant difference (χ2 = 5.120, P = 0.024; t = -2.250, P = 0.041). The elbow function Flynn evaluation score had no significant difference between two groups (P = -0.822).

CONCLUSION

The occurrence rate of cybutys varys and the decrease of carrying angle have no obvious difference in children with humeral supracondylar fractures treated with fixation in pronated or supinated position. However, when treating with pediatrics humerus supracondylar fractures with ulnar deviation, the fixation in pronation is more helpful for reducing the occurrence rate of elbow varus and decrease of carrying angle. When treating with the pediatrics humerus supracondylar fractures with radial deviation, fixation in supination is helpful for reducing the occurrence rate of elbow varus and decrease of carrying angle.