Minimally invasive osteosynthesis of distal humerus fracture with commercially available pre-contoured plate using an anterolateral fixation: mid to long-term results

Background: Surgical treatment of distal diaphyseal humerus fractures (DDHF) minimally invasive plate osteosynthesis (MIPO) has gained popularity among orthopedic surgeons as it causes less soft-tissue disruption associated with other open approaches; however, the iatrogenic radial nerve injury is still a concern. Recently, a novel technique for a MIPO through anterior approach and anterolateral fixation was proposed as an alternative to reduce the risk of radial nerve damage. Aims: To determine the mid-to-long-term functional results and safety of a MIPO through an anterior approach and anterolateral fixation using a pre-contoured locking plate modified to adjust to the anatomical surface of the lateral column of the humerus. Methods: A prospective longitudinal follow-up of patients treated for a DDHF with MIPO through an anterior approach and anterolateral fixation using a pre-contoured locking plate modified to adjust to the anatomical surface of the lateral column of the humerus. Clinical evaluations included the active range of movement (AROM), functional assessment through the Mayo Elbow Performance Score (MEPS), and pain and complications. Radiographic evaluation included assessment of consolidation, residual angulations, and the optimal plate’s position. Results: This series included ten patients with 12A,12B, and 12C fractures. Patients were followed for a median of 36.9 months (9.5 – 62.5 months). At the last evaluation, the median pain level was 1.5, the median elbow flexion was 125 degrees, and the median MEPS was 85. Two patients presented radial nerve praxia, which resolved with physical therapy. Residual angulations were minimal and within the range of acceptable alignment in the osteosynthesis of a distal diaphyseal fracture of the humerus. Conclusion: This MIPO technique with an anterior approach and anterolateral fixation for meta-diaphyseal and distal diaphyseal extra-articular humerus fractures produced a stable reduction and fixation with satisfactory mid-to-long-term clinical and functional outcomes and low complication rates.