Factors Influencing Operative Management of Adolescent Proximal Humerus Fractures

BACKGROUND: Controversy exists in the treatment of adolescent proximal humerus fractures as patients reach skeletal maturity. No universally agreed upon treatment algorithm currently exists for this population. PURPOSE: The purpose of this study is to determine risk factors that may pre-dispose a patient to have surgical treatment over non-operative treatment. METHODS: This is an IRB approved multi-center retrospective cohort study of adolescent proximal humerus fractures treated by three pediatric orthopaedic surgeons at three academic hospitals. Adolescent was defined at ages 12-17. Variables analyzed include age, weight, mechanism of injury, treatment, associated injury, Neer-Horowitz (NH)grade, neck-shaft angle of the AP, axillary lateral and scapular Y view. Two-sample T-test was used to analyze continuous variables and categorical variables were analyzed using Chi-square test. RESULTS: A total of 76 patients met inclusion criteria. 38.2% of patients received operative management. 28/76 (37%) fractures were classified as NH1, 22/76 (29%) as NH2, 12/76 (16%) as NH3 and 14/76(18%) as NH4. 4% of NH1, 17% of NH2, 100% of NH3, and 100% of NH4 fractures were treated operatively (p<0.001). When these fractures were simplified into <1/3 (NH1,2) or >1/3 displaced (NH3,4), the latter group had operative intervention more often (83% vs 4%) with risk ratio (RR) of 9.23 (P<0.001). Patients who were treated operatively were older (14.1yrs) than those who were managed non-operatively (13.3yrs) (p=0.01). Of the patients in the operative group, those who were treated with ORIF were older (15.2yrs) than those who were treated via percutaneous methods (13.8yrs) (p=0.01). Adolescents who were pedestrian struck were more likely to undergo operative management than other mechanisms RR=2.2 (p<0.01). Those who were polytraumatized more likely to undergo operative management than those with isolated injuries RR= 1.9 (p=0.02). Patient gender, BMI, weight, initial neck/shaft angulation and race were not found to be predictive of operative intervention. CONCLUSION: At the time of injury, factors that predispose an adolescent patient with a proximal humerus fracture to operative intervention are increased age, greater fracture displacement, pedestrian struck mechanism and being polytraumatized. These findings suggest that higher energy mechanisms of injury are predictive factors for operative intervention in adolescent proximal humerus fractures.