Unicolumnar Pin Fixation of Type III Supracondylar Humeral Fractures is Associated with Over Three Times Higher Odds of Lost Reduction.

OBJECTIVES To compare the rate of lost reduction between two groups of non-age segregated type III supracondylar humeral fracture patients: a unicolumnar versus bicolumnar fixation group. DESIGN Retrospective cohort study. SETTING Pediatric Academic Trauma Center. PATIENTS We identified 257 patients with Type III supracondylar humerus fractures from surgical billing records over a 5-year period. There were 183 patients identified with bicolumnar fixation (71.2%) and 74 patients identified with unicolumnar fixation (28.8%). INTERVENTION Closed reduction percutaneous pinning of the distal humerus. MAIN OUTCOME MEASURES The primary outcome measure was difference in rate of lost reduction between patients with bicolumnar (lateral and medial column) and unicolumnar (lateral column only) fixation (Figure1). The reduction and fixation at time of fluoroscopy was assessed using the Baumann angle, Gordon index, and anterior humeral line. Loss of reduction was assessed at time of healing, defined by a Baumann angle change ≥ 10 degrees and Gordon index of ≥ 50 percent (Figure2). RESULTS There were 183 patients with bicolumnar fixation and 74 patients with unicolumnar fixation included in the study (average age 5.8 years, range 2-14 years). The rate of lost reduction in patients with bicolumnar fixation was 6.01% (11/183) whereas 17.57% (13/74) of patients with unicolumnar fixation experienced lost reduction. These rates were significantly different (p=0.008) with a 3.3 times higher odds [95% CI = 1.3, 8.6] of lost reduction with unicolumnar fixation. CONCLUSIONS There is a statistically significant increase in the rate of supracondylar fracture loss of reduction for patients with unicolumnar fixation when compared to bicolumnar fixation. LEVEL OF EVIDENCE Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.