Proximal humerus Fracture treated by Modified MIROS technique: Clinical Results

Open Access

Abstract

Background: Proximal humerus fractures involving the surgical neck are common injuries in elderly patients with osteoporotic bone. The Minimally Invasive Reduction and Osteosynthesis System (MIROS) offers a less invasive fixation option, but evidence from South Asian populations remains limited. This study evaluated clinical, functional, and radiological outcomes of surgical neck fractures treated with MIROS. Methods & Materials: This observational study was conducted at National Institute of Traumatology and Orthopaedic Rehabilitation (NITOR), Dhaka, Bangladesh, over a one-year period from January 2024 to December 2024. A total of 20 consecutive patients with closed comminuted surgical neck fractures of the humerus treated using MIROS. Patients were followed at 6, 12, and 18 months. Primary outcome was union versus non-union. Secondary outcomes included shoulder range of motion measured by goniometry and documented complications. Results: The cohort comprised 55% females with 60% aged 66-75 years. Mechanism of injury included falls (55%) and road traffic accidents (45%). Union was achieved in 16 patients (80%) while 4 (20%) developed non-union. At 18 months, the union group demonstrated significantly better shoulder range of motion compared to non-union: forward flexion 162.4° ± 10.5° versus 92.5° ± 16.8° (p<0.001) and abduction 155.2° ± 11.6° versus 78.5° ± 15.2° (p<0.001). Complications occurred in 10 patients (50%), with shoulder stiffness (20%) and pin tract infection (10%) being most common. Pin tract infection led to early MIROS removal in 50% of non-union cases. Conclusion: MIROS fixation achieves favorable union rates and functional outcomes in surgical neck fractures of the humerus. Pin tract infection represents a preventable cause of non-union, highlighting the importance of rigorous pin site care protocols.