Percutaneous Fibular Nail for Ankle Fractures: An Anatomic Mapping Study.

Background: Intramedullary fibular nailing for ankle fracture fixation has gained popularity, particularly in patients at elevated risk of wound complications. Despite its benefits, concerns remain regarding its safety and the quality of fracture reduction achieved through the minimally invasive approach. This anatomical study evaluated the potential risks to adjacent structures during percutaneous retrograde locked intramedullary fibular nail implantation and assessed fracture reduction via radiographic analysis. Methods: Ten cadaveric lower extremities underwent simulated Weber B or C fractures and fixation with a nail. Reduction quality was evaluated fluoroscopically and graded accordingly. Specimens were dissected to assess damage to nearby anatomical structures, and the shortest distances between surgical sites and adjacent structures were measured. Results: Reduction quality was deemed adequate in all specimens. No peroneal tendon injuries were observed. The mean distance between the sural nerve and the distal portal was 14.95 mm (SD 3.99); therefore, this was considered a safe zone. The superficial peroneal nerve (SPN) was identified as the structure at the highest risk of injury, with a mean distance of 4.52 mm (SD 3.27) from the anterior portal and 14.17 mm (SD 5.25) from the lateral portal. The SPN was found in contact with the anterior portal in 3 specimens; however, no structures were injured during instrumentation. Conclusion: In this cadaveric model, the superficial peroneal nerve was the structure at greatest anatomic risk, particularly at the anterior portal, where direct contact was observed in 3 of 10 specimens. All specimens achieved the study-specific reduction threshold. No macroscopic nerve or tendon injury was observed during instrumentation; however, microscopic or functional injury cannot be excluded given the limitations of cadaveric dissection. Clinical Relevance: The current findings support intramedullary nailing as an effective method for achieving adequate fracture reduction while minimizing soft-tissue complications. Nevertheless, strict adherence to the percutaneous technique is essential to minimize iatrogenic injury to neighboring structures. This includes using skin-only incisions, performing blunt dissection down to the bone, and maintaining close approximation of protection sleeves and bone at all times.