Toroidal vortices, also known as vortex rings, are whirling, closed-loop disturbances that form a characteristic ring shape in liquids and gases and propagate in a direction that is perpendicular to the plane of the ring. They are well-studied structures and commonly found in various fluid and gas flow scenarios in nature, for example in the human heart, underwater air bubbles and volcanic eruptions1–3. Here we report the experimental observation of a photonic toroidal vortex as a new solution to Maxwell’s equations, generated by the use of conformal mapping4–7. The resulting light field has a helical phase that twists around a closed loop, leading to an azimuthal local orbital angular momentum density. The preparation of such an intriguing state of light may offer insights for exploring the behaviour of toroidal vortices in other disciplines and find important applications in light–matter interactions, optical manipulation, photonic symmetry and topology, and quantum information8–17.

ObjectiveTo summarize the indications and the clinical effects of a transfibular neck osteotomy approach and a combined anterolateral and posterolateral approach in the treatment of fractures of the lateral tibial plateau involving the posterolateral column.MethodsEleven patients with lateral tibial plateau fractures were included in the present study. The fractures were Schatzker type II or lateral platform fractures involving posterolateral column. The anterolateral combined posterolateral approach (lateral + posterolateral locking plate fixation) was applied in 7 patients and 4 patients underwent transfibular neck osteotomy (lateral + posterolateral locking plate fixation + 1/4 tubular plate edge fixation, fibular osteotomy with Kirschner wire tension band fixation, and hollow nail fixation for upper tibiofibular joint). All cases were followed up for 12–24 months, with an average follow‐up of 17.5 ± 5.0 months. At the last followup, the Rasmussen radiological criteria were used to evaluate the effect of fracture reduction and fixation. The knee joint function was evaluated using the knee function evaluation criteria of the Hospital for Special Surgery (HSS). The Lachman test and the pivot‐shift test were used to evaluate the anterior and posterior and rotational stability of the knee joint. The range of knee motion was recorded.ResultsBone healing was achieved in all patients with fractures treated with a transfibular neck osteotomy approach and a combined anterolateral and posterolateral approach. At the last follow‐up, both the Lachman test and the pivot‐shift test results were negative. All patients had complete knee extension. For the combined anterolateral and posterolateral approach, the knee flexion angle was 110°–130°, with an average of 122.86° ± 7.56°. For the transfibular neck osteotomy approach, the knee flexion angle was 115°–130°, with an average of 120.00° ± 7.07°. For the patients in which the combined anterolateral and posterolateral approach was used, the Rasmussen score was 12–18 points, with an average of 16.00 ± 2.56 points. The results were excellent in 4 cases and good in 3 cases; therefore, 100% of results were excellent or good. For patients in which the transfibular neck osteotomy approach was used, the Rasmussen score was 10–18 points, with an average of 15.25 ± 3.77 points. The results were excellent in 2 cases, good in 1 case, and acceptable in 1 case; therefore, 75% of results were excellent or good. The HSS score for the combined anterolateral and posterolateral approach was 76–98 points, with an average of 88.43 ± 7.55 points. The results were excellent in 5 cases and good in 2 cases; therefore, 100% of results were excellent or good. The HSS score for the transfibular neck osteotomy approach was 74–96 points, with an average of 87.25 ± 9.43 points. The results were excellent in 3 cases and good in 1 case; therefore, 100% of results were excellent or good. There were no significant differences in operation time, surgical blood loss, fracture healing time, postoperative imaging s...

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Objective The aim of the present study was to summarize the clinical characteristics, treatment strategies, and clinical results for anterior tibial plateau fractures caused by hyperextension injuries. Methods We performed a retrospective analysis of 26 cases of anterior tibial plateau fractures that were treated with open reduction and internal fixation from January 2016 to December 2019, including 16 men and 10 women, aged 26–68 years old, with an average age of 47 ± 12.5 years. According to the three‐column theory classification, there were 16 cases of single‐column fractures (9 cases of anteromedial fractures and 7 cases of anterolateral fractures), 3 cases of two‐column fractures (anteromedial + anterolateral fractures), and 7 cases of three‐column fractures. Options for the surgical approach included anteromedial, anterolateral, modified anterior median, and anterolateral + posteromedial incision. The implants included a T‐shaped plate, an L‐shaped plate, a horizontal plate, and a TomoFix plate. The surgical approach and fixation method were selected based on the characteristics of the anterior tibial fracture. The Rasmussen radiological criteria were used to evaluate the effects of fracture reduction and fixation. The knee joint function was evaluated using the knee function evaluation criteria of the Hospital for Special Surgery. Medial and lateral stress tests, the Lachman test, and the pivot shift test were used to evaluate the stability of the knee joint. The range of knee motion was recorded. Results All cases were followed up for 12–24 months, with an average follow up of 15.7 months. The operation time was (148 ± 42) min; the intraoperative blood loss was (150 ± 50) mL. A total of 22 cases were anatomically reduced and 4 cases were well‐reduced, and the compression reduction rate was 100%. According to the Rasmussen radiology scoring, 17 cases were excellent and 9 cases were good. The excellent and good rate was 100%. The fracture healing time was 3.3 months. There is no difference in fracture healing time for different fracture types. Both the Lachman and pivot shift test findings were normal in 24 patients and nearly normal in 2 patients. The posterior drawer test was normal in 25 patients and close to normal in 1 patient. The varus stress test was normal in 24 patients and nearly normal in 2 patients, while the valgus stress test was normal in 23 patients, nearly normal in 2 patients, and abnormal in 1 patient. The range of motion (ROM) was 100°–137°, with an average of 125° ± 11.7°. The Hospital for Special Surgery (HSS) knee score at the last follow up was 79–98 points, with an average of 87.54 ± 8.36 points; the results were excellent in 21 cases and good in 5 cases. Therefore, 100% of results were excellent or good. Two cases had superficial wound infections after the operation. The recovery of 2 patients with common peroneal nerve injury was poor. Conclusion The appropriate surgical approach and fixation method were performed according to the different positions of the anterior tibial fractu...

Pulse shaping has become a powerful tool in generating complicated ultrafast optical waveforms to meet specific application needs. Traditionally, pulse shaping focuses on the temporal waveform synthesis. Recent interests in structuring light in the spatiotemporal domain rely on Fourier analysis. A space-to-time mapping technique allows us to directly imprint complex spatiotemporal modulation through taking advantage of the relationship between frequency and time of chirped pulses. The concept is experimentally verified through the generation of spatiotemporal optical vortex (STOV) and STOV lattice. The power of this method is further demonstrated by STOV polarity reversal, vortex collision, and vortex annihilation. Such a direct mapping technique opens tremendous potential opportunities for sculpturing complex spatiotemporal waveforms.