Anterior Minimally Invasive Plate Osteosynthesis Versus Open Reduction Plate Osteosynthesis in Humeral Diaphyseal Fractures: A Functional and Clinical Analysis

Introduction: The scope of this research was to examine the radiographic healing and functional results in OTA/AO type 12A and 12B humeral diaphyseal fractures (HDFs) treated surgically either by anterior minimally invasive plate osteosynthesis (MIPO) or by open reduction plate osteosynthesis (ORPO) along the posterior cortex of the humerus. Materials and Methods: In this prospective cohort observational analysis, experienced orthopedic surgeons performed two different surgeries in two non-randomly allocated groups of 30 patients each. Outcomes measured radiographic healing, defined as cortical bridging on orthogonal radiographs, and shoulder and elbow functional scores at multiple intervals over 1 year using the University of California at Los Angeles (UCLA), the mayo elbow performance index (MEPI), and the disabilities of the arm, shoulder and hand (DASH) scores comparing the outcomes between both interventions using different statistical methods. Results: The study found insignificant variations in the age, sex, or AO/OTA fracture types between the groups. MIPO group had a significantly shorter time to healing (13.1 ± 3.1 weeks vs. 18.1 ± 4.7 weeks; P = 0.03), a better functional result of the shoulder and elbow (UCLA: 34.2 ± 2.7 vs. 32.8 ± 3.1; P = 0.05; MEPI: 90.3 ± 10.8 vs 88.7 ± 9.8; P = 0.04), and a lower DASH score (15.8 ± 3.1 vs. 17.9 ± 5.8; P = 0.03) than ORPO. Complications included two non-unions in ORPO and one in MIPO; radial nerve palsy occurred in four cases treated with ORPO. Conclusion: Anterior MIPO is a biologically favorable and skill-dependent approach for managing HDFs. While not simply a replacement for ORPO, it affords earlier radiographic union, reduced surgical morbidity, enhanced recovery of shoulder and elbow function, fewer secondary interventions, and allows safe avoidance of the radial and musculocutaneous nerves.