Anatomic locking plates for complex proximal humeral fractures: anatomic neck fractures versus surgical neck fractures

Background: Continued debate exists on the management of displaced 3- or 4-part proximal humeral fractures. Only a few studies have compared the efficacy of proximal humeral locking plates (PHLPs) for treating anatomic neck fractures (ANFs) and surgical neck fractures (SNFs). Methods: The medical data of 31 consecutive patients with displaced 4-part proximal humeral. fractures treated with PFILPs between May 2013 and April 2015 were reviewed retrospectively. We divided the patients into the ANF and SNF groups and assessed the neck-shaft angle (NSA), sum of the screw tip- articular surface distance, and other parameters postoperatively at 3 days and at 12 months using shoulder radiographs. The Constant-Murley scores were assessed at 3 days, 12 months, and last follow-up. Results: The ANF group had a significantly lower mean age and significantly greater mean operative duration. estimated blood loss, and rate of bone grafting. Full or partial osteonecrosis of the humeral head developed in 7 patients and 1 patient in the ANF and SNF groups, respectively. Screw cutout and/or pullout complications occurred in 8 cases in the ANF group but not in the SNF group. In the ANF group, the values for NSA and the sum of the screw tip-articular surface distance changed significantly from 3 days to 12 months postoperatively. There were no significant correlations among the tested parameters. Conclusion: ANFs resulted in more complications at a younger age than SNFs. ANF treatment using PHLPs is more prone to a decreased NSA and humeral head osteonecrosis and has poorer clinical outcomes than SNF treatment using PHLPs. (C) 2018 Journal of Shoulder and Elbow Surgery Board of Trustees. All tights reserved.