RESUMEN
PURPOSE: To develop a predictable and reproducible model of knee osteoarthritis after medial meniscus posterior root release. METHODS: Posteromedial meniscal root tears were created in 12 White New Zealand rabbit knees. The contralateral limbs were used as healthy controls. The animals were euthanized at 16 weeks postoperatively; tissue samples of femoral and tibial articular cartilage were collected and processed for macro and microscopic analyses to detect signs of early degeneration. Clinical evaluation of the weight-bearing status on the affected knee was conducted at 0-, 4-, 8-, and 16-weeks postoperatively. RESULTS: Early and severe osteoarthritic changes were the hallmark and the main findings after 16-weeks post-surgery. Macroscopically, extensive osteoarthritic changes were observed across the femoral condyle and tibial plateau. Microscopic finding included ulcerations, fissures, fibrillations, pitting, and loss of the superficial layer. Cellularity was diminished, the normal pattern of distribution in columns was lost, and subchondral bone exposure was also evident. CONCLUSIONS: This study describes a novel model of knee osteoarthritis that may guide the development of tailored interventions to delay or prevent knee osteoarthritis. This knowledge could shift the current treatment paradigm toward more conservative and knee salvageable treatment options and increase surgeons' awareness of this injury pattern. Such considerations may have a positive impact on clinical decision-making and subsequent patient-reported clinical outcomes. DESIGN: Controlled laboratory study. LEVEL OF EVIDENCE: II.
RESUMEN
OBJECTIVES: Head and neck surgery is associated with a steep learning curve, creating a need for effective training methods. Live animal models can be useful in acquiring the required skills and techniques to perform tracheostomy, neck dissection, and laryngectomy. The aim of this study is to assess the feasibility and usefulness of a porcine model to teach tracheostomy, neck dissection, and laryngectomy, describing the similarities between a swine head and neck surgical model and the human cervical area. METHODS: Twelve surgical training sessions were held with the use of a live porcine model maintained under general anaesthesia; a total of 39 procedures were performed. In each session, one otolaryngology resident per year performed a procedure to acquire the targeted competencies for their respective year of training. Each procedure was time recorded and evaluated based on a modified Objective Structured Assessment of Technical Skills. Linear regression was used to analyse the data and express the results as percentages. RESULTS: Training exercises were performed in shorter times over the study period. A 9% reduction in the time spent was observed. There was a global improvement in the evaluation made by OSATS score of 6% in the first period (2018-2019) and 58% in the second period (2019-2020). CONCLUSION: The porcine model was both manageable and helpful in providing training despite slight anatomical differences between human beings and pigs. However, more studies are necessary to guarantee that the competencies acquired with this type of training are transferable to real-life interventions. LEVEL OF EVIDENCE: Level 5.
