Objective: This study sought to describe a modified arthroscopic technique in which a traction device with a horizontal vector and nylon mesh are used to allow continuous and uniform distraction without requiring an assistant surgeon to perform manual traction. Methods: Nine patients (seven females and two males; mean age 31.8 [30-52] years) with an indication for treatment of this joint who had been diagnosed with different pathologies, including synovitis, hallux vagus, and hallux rigidus, were selected and underwent arthroscopy of the first metatarsophalangeal joint using this modified technique. Results: Patient evaluations determined using the American Orthopedic Foot and Ankle Society (AOFAS) Ankle-Hindfoot Scale were recorded before and after surgery. The mean scores before and after the procedure were 43.66 (32-55) and 95.22 (90-8), respectively. No scars or joint complications were observed at a six-month follow-up, and all subjects experienced rapid recovery and quickly returned to daily functions. Conclusion: Similarly to conventional arthroscopy of the metatarsophalangeal joint, the modified technique produced satisfactory surgical outcomes; moreover, this technique reduced surgical time and improved the surgeon’s autonomy by obviating the need for an assistant surgeon to perform traction. Level of Evidence IV; Therapeutic Studies; Case Series.

Objective: The aim of this study was to evaluate the effectiveness of arthroereisis using synthetic polyethylene implants as a method to correct deformities of excessive valgus in pediatric patients with flexible flatfoot (FF). Methods: This was a study of 20 patients between 5 and 12 years of age with symptomatic FF who received surgery between January 2011 and July 2016. Evaluations were made on the basis of the Valenti podoscopic classification, radiographic images, and AOFAS criteria. Patients with preoperative Valenti classification grades of III and IV were selected for the study. These patients received surgical treatment by arthroereisis with the interposition of a synthetic implant in the sinus tarsi, with or without stretching of the Achilles tendon (Vulpius surgery). A multiple linear regression analysis was performed with backward selection of the following variables: Valenti preoperative classification and the preand postoperative Bordelon, Kite, Gould, Meary and Pitch angles that were measured from the radiographic images of the patients who received arthroereisis. Results: Arthroereisis with synthetic material interposition was satisfactory, with 21 of the feet (91% of cases) showing clinical and radiographic improvement with angle correction and improved degree of deformity based on the Valenti classification. Two cases experienced implant loosening. The Bordelon and Pitch angle variables had a significant effect (p<0.05) on the improvement in degree of deformity correction based on the Valenti classification. Conclusion: Arthroereisis resulted in significant improvements in the patients who were studied, with pronounced clinical improvement and high degrees of satisfaction. Level of evidence IV; Therapeutic Studies; Case Series.