Stiffness of various pin configurations for pediatric supracondylar humeral fracture: a systematic review on biomechanical studies.

To compare the biomechanical stability of various pin configurations for pediatric supracondylar humeral fractures under varus, internal rotation, and extension conditions. After electronic retrieval, 11 biomechanical studies were included. Stiffness values of pin configurations under different loading conditions were extracted and pooled. There were no statistically significant differences between two cross pins and two divergent lateral pins on the basis of the 'Hamdi method' (P=0.249-0.737). An additional pin did not strengthen two-pin construct (P=0.124-0.367), but better stabilized fractures with medial comminution (P<0.01). Isolated lateral pins are preferable because of a better balance of a lower risk of nerve injury and comparable fixation strength. Limitations such as differences in experimental setup among recruited studies and small sample size may compromise the methodologic power of this study.