
Introduction: Humeral non-union, which can occur in conservatively treated fractures and surgically managed cases, presents significant challenges. Combining non- vascularized fibular autografts (NVFG) with locking compression plates (LCP) may offer a reliable method for achieving bone union and restoring function in such patients. Therefore, this study aims to evaluate the functional outcomes of autologous NVFG and LCP for failed fixation of humeral shaft with atrophic gap non-union. Methodology: This prospective study included 17 patients treated for humeral fracture nonunion, with a minimum follow-up of 24 months. Clinical evaluation included preoperative and postoperative Disabilities of the Arm, Shoulder, and Hand (DASH) scores, while radiographic union was monitored during follow-up. Surgical techniques involved harvesting fibular grafts, debridement, and fixation using LCP with NVFG. Results: The mean age of patients was 51.23 years, with a duration of nonunion averaging 13.53 months. Preoperative DASH scores averaged 61.18 ± 6.49, improving significantly to 27.76 ± 6.12 postoperatively (p < 0.0001). Radiological union was confirmed in all cases, with no pain reported at fracture sites. Two patients experienced surgical site infections, while one developed transient peroneal nerve palsy, indicating a low complication rate. Conclusion: The combination of NVFG and LCP for treating humeral shaft non-union with an atrophic gap resulted in excellent functional outcomes and high union rates. This technique is a reliable option for complex humeral non-union, offering effective structural support and significant functional recovery.