Proximal humerus fractures are common injuries. Although certain fracture types may benefit from surgery including open reduction internal fixation (ORIF), the optimal method for fixation is unclear. Newer implant designs that improve healing by minimizing hardware failure and recurrent fracture displacement may optimize clinical outcomes.
Over a 27 month period, 37 consecutive patients with proximal humerus fractures were treated by a single surgeon with a lateral humeral plate though which an intramedullary nitinol cage was inserted. Additional screws were placed through the tuberosities and cage as required. Fractures were classified by both the Neer classification and angulation or displacement in the coronal plane. At most recent follow-up, radiographic results, patient reported outcome measurements, range of motion, complications and re-operations were recorded.
Thirty-one patients had a minimum of 1 year of clinical and radiographic follow-up. Average follow-up was 91 weeks. Using the Neer classification, there were 4 two part, 21 three part, and 6 four-part fractures. Twenty-one fractures were displaced in valgus and 10 in varus. Outcome measurements at most recent follow-up demonstrated an average ASES (68), Single Assessment Numeric Evaluation (70), quick DASH (27), Veterans Rand-12 (PCS 37 and MCS 51), Constant score (55), PROMIS (29), Oxford Shoulder Score (23). Average active range of motion was 134 for forward elevation, 91 for abduction, 30 (-10 to 60) of external rotation with the arm at the side and to L1 (T6-S4) for internal rotation with the arm at the side. There were 11 complications (35%), including two axillary nerve neuropraxias that resolved and four cases of AVN (13%). Six patients had unplanned re-operations (19%). One revision was for loose hardware removal, one for revision ORIF after a fall, and four for component removal and revision to shoulder arthroplasty. There was no screw cutout or varus head collapse.
The management of proximal humerus fractures remains challenging. Our results demonstrate similar fracture healing, clinical improvement and complication rates compared to conventional ORIF with screws and a side plate. At one year follow-up, there are low rates of recurrent fracture displacement and screw cutout. There were higher than expected rates of AVN as compared to other studies using a similar fixation construct. Larger studies and longer follow-up may demonstrate decreased rates of revision surgery and superior outcomes. Additional studies may determine whether this fixation method is superior to others for proximal humerus fractures.

Copyright © 2021. Published by Elsevier Inc.