Complications and Early-Term Radiographic Analysis of a Novel Active Compression Tibiotalocalcaneal Arthrodesis Nail With a Proximal Flexible Coil.

Background: Tibiotalocalcaneal (TTC) arthrodesis is used among other methods as a salvage procedure for complex foot/ankle deformity. Fixation is usually achieved through plate/screw constructs or intramedullary (IM) nailing. Although IM nailing uses smaller incisions, fusion rates are variable and complications rates ranging from 25% to 55.7% have been reported. The Phantom ActivCore (AC) nail could serve as a viable alternative to traditional IM nailing by allowing for increased compression capacity and a potentially lower risk of stress fracture. However, no studies have described the early outcomes of TTC arthrodesis using the AC nail. The primary objective of this study was to determine the rates of early-term complications and radiographic union of the AC nail.

Methods: Inclusion criteria consisted of patients who had undergone a tibiocalcaneal or TTC arthrodesis using the Phantom Hindfoot TTC Nail System with at least 6 months of follow-up. Radiographic analysis evaluated for successful union and flexibility of the flex coil. Patients were monitored for postoperative complications and additional secondary procedures.

Results: Twenty-one patients were included and had an average follow-up of 9.4 ±4.7 months (range, 4.3-19 months). No intraoperative complications were reported. Seven patients experienced at least 1 adverse event, which included device migration, asymptomatic nonunion, symptomatic nonunion, bone stress reaction, device prominence, and screw breakage. There were no events of perioperative fractures or device breakage. Two patients required secondary surgical interventions. The 5 remaining patients were managed conservatively. An average nail coil flexion angle of 2.6 ± 3.1 degrees and 0.8 ± 1.59 degrees was found on lateral and anteroposterior radiographs, respectively. The overall union rate at a mean follow-up of 9.4 months was 90.4% (95% CI 69.6%, 98.8%).

Conclusion: TTC arthrodesis via the AC nail demonstrated similar union rates and outcomes at short-term follow-up compared with rates generally reported in the literature for other IM nail constructs. The AC nail was able to function as designed and allow for motion at the proximal bone-implant interface.

Level of evidence: Level IV, retrospective case series study.