1430 Mid-Term Outcomes After Endovascular Repair of Popliteal Artery Aneurysms Demonstrate Satisfactory Patency Rates and Safety of Stent-Grafts

Aim Popliteal artery aneurysms (PAAs) are increasingly treated via an endovascular approach. We present mid-term outcomes of popliteal endovascular aneurysm repair (PEVAR) from a single centre. Method A retrospective analysis of a prospective database of consecutive patients who underwent either elective or emergency PEVAR in a single regional vascular centre from January 2010 to August 2020. The patients underwent placement of a heparin-bonded stent-graft (Viabahn Endoprosthesis, WL Gore and Associates, Flagstaff, USA) for PAA >20mm or complications: thromboembolism, rupture or popliteal vein thrombosis. Patency and stent-graft related complications were assessed. Results A total of 64 PAAs (mean size 36.8±13.4mm) were treated in 56 patients (mean age 75±10.7 years, 54 (96%) male). Median follow-up was 29.5 months (IQR 36.75). 30-day mortality was 0%. Technical success rate of stent-graft insertion was 100%. 1-year and 5-year primary patency was 83% and 67% respectively; primary-assisted patency at these time points was 86% and 72%, and the corresponding secondary patency was 89% and 75%. 61 out of 64 treated limbs had >1 vessel runoff. The most frequently occurring complication was stent-graft occlusion which affected 11 (17%) limbs. Stent-graft fracture occurred in 1 patient, resulting in endoleak. Conclusions Viabahn Endoprosthesis can be used successfully in treatment of PAA with acceptable short- and mid-term patency rates. One in five patients in this cohort required a reintervention, with most complications occurring in the first year postoperatively. Stent-graft fracture occurred only in one patient demonstrating that PEVAR is a safe option for PAA management in the intermediate term.

Biomechanical analysis of costochondral graft fracture in temporomandibular joint replacement

This study is the first attempt to explore the reason of costochondral graft fracture after lengthy mandible advancement and bilateral coronoidectomy by combining finite element analysis and mechanical test. Eleven groups of models were established to simulate costochondral graft reconstruction in different degrees of mandible advancement, ranging from 0 to 20 mm, in 2 mm increment. Force and stress distribution in the rib-cartilage area were analyzed by finite element analysis. Mechanical test was used to evaluate the resistance of the rib-cartilage complex. Results showed a sharp increase in horizontal force between 8 and 10 mm mandible advancement, from 26.7 to 196.7 N in the left side, and continue increased after 10 mm, which was beyond bone-cartilage junction resistance according to mechanical test. Therefore, we concluded that bilateral reconstruction with coronoidectomy for lengthy mandible advancement (≥ 10 mm) may lead to prominent increase in shear force and result in a costal-cartilage junction fracture, in this situation, alloplastic prosthesis could be a better choice. We also suggested that coronoidectomy should be carefully considered unless necessary.

Onlay vascularized fibular grafting as a salvage procedure for the management of nonunion after reconstruction of the femur following tumor resection

Purpose: The femur is prone to nonunion after biologic reconstruction following tumor resection, due to high bending forces. Nonunion at the host–graft junction is difficult to treat since the graft is in an avascular state. We aimed to investigate the clinical and radiographic results of an onlay free vascularized fibular grafting (VFG) as a salvage procedure for nonunion management after biologic reconstruction of the femur following bone tumor resection. Methods: We retrospectively reviewed 10 patients (8 men and 2 women, median age: 15.5 years, range: 10–47) who underwent an onlay VFG for nonunion after intercalary reconstruction of the femur using an allograft ( n = 7) or pasteurized autograft ( n = 3), following tumor resection. The median follow-up period after VFG was 85.7 (24.6–163.5) months. Results: The median time to union between the host bone and the VFG osteotomy sites was 3.5 (2.8–4.5) months. The median time to union at the host–graft junctions was 10.6 (6.6–12.7) months. Two postoperative complications requiring revision surgery occurred in two patients: one graft fracture and one deep infection with synchronous graft fracture. Internal fixation was required in the patient with graft fracture. The patient with the infection and synchronous graft fracture was treated using debridement, antibiotics, and an external fixator. The median Musculoskeletal Tumor Society functional score was 88% (60–97%) at the final follow-up. Conclusion: Onlay VFG as a salvage procedure for nonunion of a biologic intercalary reconstruction of the femur after tumor resection is a useful treatment option.