Comparative Outcomes of MIPO vs ESIN in Complex Pediatric Tibial Fractures: Diaphyseal AO 42B-C and Extra-articular Distal AO 43A2-A3.

Abstract

Elastic Stable Intramedullary Nailing (ESIN) is a common treatment for pediatric tibial fractures, especially in standard diaphyseal fracture patterns and normal body mass index (BMI). However, ESIN may be technically limited in complex fracture morphologies (AO 42B-C, 43A2-A3) and in heavier children. Minimally Invasive Plate Osteosynthesis (MIPO), a technique widely embraced in adult orthopaedic trauma, may provide more stable fixation in these challenging scenarios through mini-incisions, indirect reduction strategies, and a stable "sliding plate" construct that preserves fracture biology. To compare clinical and radiographic outcomes of MIPO versus ESIN in diaphyseal AO 42B-C and extra-articular distal AO 43A2-A3 fractures. Single-center, retrospective cohort over 7 years, including skeletally immature patients (6 to 15 y) with diaphyseal AO/OTA 42B-C or extra-articular distal AO/OTA 43A2-A3 fractures. Intra-articular distal (43B-C) and physeal injuries were excluded. Primary outcomes were time to radiographic union and major complications (deep infection, loss of alignment requiring unplanned surgery, and implant bending/migration). Secondary outcomes included return to full sport, minor complications (superficial irritation/entry-site), residual deformity >5 degrees, and shortening >1 cm. Fifty-eight children were analyzed (MIPO n=25; ESIN n=33). Union occurred sooner after MIPO (10.6±1.8 wk) than ESIN (15.8±2.5 wk) (P <0.001). Return to full sport was earlier with MIPO (13.3±1.7 wk) versus ESIN (20.6±2.4 wk) (P <0.001). Major complications occurred in 6/25 (24%) after MIPO and 10/33 (30%) after ESIN (P=0.41); unplanned reoperations were 0/25 (0%) with MIPO and 8/33 (24%) with ESIN. Minor complications were comparable (40% vs. 42%, P=0.61), as was residual deformity >5 degrees (24% vs. 27%, P=0.564). Findings were directionally consistent in overweight children. For complex extra-articular tibial fractures (42B-C; 43A2-A3), MIPO yielded faster union, earlier return to sport, and fewer reoperations than ESIN. Simple mid-diaphyseal fractures in lightweight children may still be managed nonoperatively or with standard ESIN. Level III.