MIPO helical pre-contoured plates in diaphyseal humeral fractures with proximal extension. Surgical technique and results

Abstract

IntroductionThe aim of this study was to determine the feasibility of applying the MIPO technique with a helical-shaped plate in the treatment of humeral shaft fractures with proximal extension. Patients and methodsWe present an observational prospective study of patients with a humeral shaft fracture involving the proximal humerus fixed with a long proximal humerus polyaxial locking plate with an anterior curvature and helical shape (ALPS® Zimmerbiomet, Warsaw, Indianapolis, USA), using a MIPO technique. Between January 2017 and July 2020, 15 patients were treated at our institution. Proximally a 4–5 cm anterolateral transdeltoid approach was made. And distally, a 5–7 cm incision was made 4 cm proximal to the elbow crease. At each follow-up, radiographs were taken to evaluate fracture healing. Funtional scales were applied to evaluate clinical results. ResultsTen women and five men were included, with a mean age of 62 yo (range 26–86). All but one fracture healed uneventfully. The mean time to union was 28 weeks (range 12–48 weeks). Two out of 15 patients presented complications (an atrophic nonunion and a peri‑implant distal fracture). None of the patients had a nerve palsy prior neither after the surgery. No other complications, including infection, were registered during follow-up. Shoulder range of motion showed the following means: abduction of 147° (range 50°-180°), anterior flexion of 144° (range 80°-180°), external rotation of 77,5 ° (range 70°-80°) and internal rotation of 54.5° (range 45°-60°). All patients recovered their pre-fracture elbow range of motion. All patients presented less than 10° of angular deviation in varus/valgus or ante/recurvatum after the surgical procedure. At the end of the follow-up, all final functional scores were “good” or “excellent”: mean Constant-Murley score was 72 ± 13 (range 38–91), ASES score was 73 ± 12 (range 41–88), UCLA shoulder scale was 30 ± 3,5 (range 10–35), and Q-DASH score was 16.5 ± 0,11 (range 4–57). ConclusionWhen applied correctly, the treatment of diaphyseal humeral fractures involving the proximal humerus using a polyaxial locking helical plate with a MIPO technique is a reliable treatment method. It has high union rates with low complications.