A systematic review of medial and lateral entry pinning versus lateral entry pinning for supracondylar fractures of the humerus

The supracondylar fracture of the distal humerus is the most common pediatric fracture in the elbow. This systematic review summarizes the existing data about the effect of medial and lateral (media/lateral) entry pins versus only lateral entry pin fixation on the risk of iatrogenic nerve injury and deformity or loss of reduction. A literature search identified clinical trials and observational studies presenting the probability of nerve injury and/or deformity or loss of reduction associated with closed reduction and either medial/lateral entry or lateral entry pinning of supracondylar fractures in pediatric patients. Data from 2054 children were identified from 35 studies; 2 randomized trials, 6 cohort studies, and 25 case series. For operative fixation with medial/lateral entry pins, the probability of ulnar nerve injury is 5.04 times higher than with lateral entry pins. When all documented operative nerve injuries are included, the probability of iatrogenic nerve injury is 1.84 times higher with medial/lateral entry pins than with isolated lateral pins. Medial/lateral pin entry provides a more stable configuration, and the probability of deformity or loss of reduction is 0.58 times lower than with isolated lateral pin entry. When the prospective studies alone were analyzed, there were no significant difference in the probability of iatrogenic nerve injury or deformity and displacement, although the confidence intervals were wide. This systematic review indicates that medial/lateral entry pinning, of pediatric supracondylar fractures, remains the most stable configuration and that care needs to be taken regardless of technique to avoid iatrogenic nerve injury and loss of reduction.