Evaluation of the Chilean National Orthopaedic Examination Over 11 Years: Progress and Outcomes of National and International Examinees.

INTRODUCTION: The National Orthopaedics Examination (EMNOT) was initially designed for Chilean orthopaedic program graduates and is now a crucial component of the revalidation process for international orthopaedic surgeons seeking practice in Chile. This study aims to describe participation and performance of EMNOT examinees based on their origin and to analyze the difficulty and discrimination indexes during its first 11 years of implementation. METHODS: A retrospective assessment was conducted on all EMNOT results from 2009 to 2019. The study evaluated the participation and performance of examinees according to their origin and examined the difficulty and discrimination indexes of the examination. RESULTS: A total of 975 examinees were evaluated, with 41.23% from national resident programs (National Medical Graduates) and 58.77% from international examinees (International Medical Graduates). The number of participating universities increased from 4 in 2009 to 17 in 2019. National Medical Graduates examinees achieved a mean score of 66.52 ± 8.67 (0 to 100 points) while International Medical Graduates examinees scored 55.13 ± 11.42 (P < 0.001). The difficulty and discrimination indexes remained adequate throughout this period. DISCUSSION: Over the course of 11 years, the number of EMNOT examinees exhibited notable growth. The examination effectively differentiates between candidates based on their origin and maintains appropriate levels of difficulty and discrimination.

Limiting Factors for Indication of Hip and Knee Arthroplasty in Chile: The International Perception of Risk Initiative.

BACKGROUND: An aging population with a resultant higher incidence of osteoarthritis have increased the need for total hip (THA) and knee arthroplasty (TKA) worldwide. The purpose of this study was to explore what medical and social risk factors are considered relevant by Chilean orthopaedic surgeons in decisions regarding indications for THA or TKA. METHODS: An anonymous survey was sent to 165 hip and knee arthroplasty surgeons who were members of the Chilean Orthopedics and Traumatology Society. From a total of 165 surgeons, 128 (78%) completed the survey. The questionnaire included demographic data, place of work, and inquired about medical and socioeconomic factors that could affect surgical indications. RESULTS: Factors that limited indications for elective THA/TKA included body mass index (81%), elevated hemoglobin A1c (92%), lack of social support network (58%), and low socioeconomic status (40%). Most respondents made decisions based on personal experience or literature review rather than hospital or departmental pressures. Of the respondents, 64% believe that some patient populations would benefit from better care if payment systems adjusted for their socioeconomic risk factors. CONCLUSION: In Chile, limitations regarding the indication for THA/TKA are most influenced by the presence of modifiable medical risk factors such as obesity, uncompensated diabetes, or malnutrition. We believe that the reason surgeons limit surgeries for such individuals is to promote better clinical outcomes, and not in response to pressure from paying entities. However, low socioeconomic status was perceived to impair the ability to achieve good clinical outcomes by 40% of the surgeons.

An Isolated Transosseous Flexible Suture Frame in the Treatment of Patellar Tendon Rupture Provides Adequate Mechanical Resistance.

INTRODUCTION: Acute patellar tendon ruptures are frequently observed in patients with metabolic comorbidities, and the benchmark treatment is surgical repair. It is desirable not to harm an already fragile biologic environment with sutures and hardware. We aimed to compare the mechanical requirements of an isolated, flexible, high-strength nonabsorbable transosseous suture frame with that of the Krackow suture technique. METHODS: A total of 12 cadaveric pieces were randomized into two groups: the isolated flexible frame group (n = 6) and the standard Krackow fixation group (n = 6). A traumatic rupture of the patellar tendon was performed, and a transosseous displacement sensor was installed on a validated biomechanical system. Gap formation was measured during 50 cycles of flexion and extension with traction on the quadriceps (250 N). Subsequently, specimens underwent progressive loading in a fixed flexion position until failure occurred. The data were analyzed using nonparametric statistical tools with a significance level of 5%. RESULTS: The isolated frame group had a smaller gap formation (1.7 mm) than the Krackow group (3.4 mm; P = 0.01). No significant difference existed in the median failure end points of the two groups (676 and 530 N, respectively; P = 0.11). DISCUSSION: Patellar tendon repair using an isolated, transosseous, flexible, suture frame outperformed using the traditional Krakow repair technique in gap formation. Further studies are needed to determine if this will result in better functional outcomes or fewer clinical failures. LEVEL OF EVIDENCE: Level IV, experimental case series.

Umbilical Cord-Derived Mesenchymal Stromal Cells (MSCs) for Knee Osteoarthritis: Repeated MSC Dosing Is Superior to a Single MSC Dose and to Hyaluronic Acid in a Controlled Randomized Phase I/II Trial.

Knee osteoarthritis (OA) is a leading cause of pain and disability. Although conventional treatments show modest benefits, pilot and phase I/II trials with bone marrow (BM) and adipose-derived (AD) mesenchymal stromal cells (MSCs) point to the feasibility, safety, and occurrence of clinical and structural improvement in focal or diffuse disease. This study aimed to assess the safety and efficacy of the intra-articular injection of single or repeated umbilical cord-derived (UC) MSCs in knee OA. UC-MSCs were cultured in an International Organization for Standardization 9001:2015 certified Good Manufacturing Practice-type Laboratory. Patients with symptomatic knee OA were randomized to receive hyaluronic acid at baseline and 6 months (HA, n = 8), single-dose (20 × 106 ) UC-MSC at baseline (MSC-1, n = 9), or repeated UC-MSC doses at baseline and 6 months (20 × 106 × 2; MSC-2, n = 9). Clinical scores and magnetic resonance images (MRIs) were assessed throughout the 12 months follow-up. No severe adverse events were reported. Only MSC-treated patients experienced significant pain and function improvements from baseline (p = .001). At 12 months, Western Ontario and Mc Master Universities Arthritis Index (WOMAC-A; pain subscale) reached significantly lower levels of pain in the MSC-2-treated group (1.1 ± 1.3) as compared with the HA group (4.3 ± 3.5; p = .04). Pain Visual Analog scale was significantly lower in the MSC-2 group versus the HA group (2.4 ± 2.1 vs. 22.1 ± 9.8, p = .03) at 12 months. For total WOMAC, MSC-2 had lower scores than HA at 12 months (4.2 ± 3.9 vs. 15.2 ± 11, p = .05). No differences in MRI scores were detected. In a phase I/II trial (NCT02580695), repeated UC-MSC treatment is safe and superior to active comparator in knee OA at 1-year follow-up. Stem Cells Translational Medicine 2019;8:215&224.

An assessment of the Chilean National Examination of Orthopaedic Surgery.

BACKGROUND: The Chilean National Examination of Orthopaedic Surgery (EMNOT) has been administered since 2009. It was developed to determine whether individual residents are meeting minimal knowledge standards at the end of their training programs. METHODS: We performed a retrospective evaluation of the EMNOT for all years it has been administered (2009-2015). The test was analyzed for content, taxonomy of questions asked (1: direct recall; 2: diagnosis; 3: evaluation/decision-making), residents' performance, difficulty index and discrimination index. RESULTS: During the years of EMNOT administration, the most frequently tested areas have been pediatric orthopaedics (22.9 %), spine (13.8 %), general orthopaedics (13.8 %) and musculoskeletal trauma (9.9 %). A significant increase in questions with images was observed, as well as a significant decrease in the percentage of Type 1 and an increase in Type 3 questions. The Difficulty Index showed a medium level of difficulty for all years the examination has been administered. The Discrimination Index showed good discrimination in 2009, fair discrimination from 2010 through 2012, and excellent discrimination from 2013 through 2015. CONCLUSION: The EMNOT has evolved over several years to include better quality questions, better discrimination, and a more representative distribution of questions covering the different orthopaedic sub-specialties. This examination represents an effective instrument for quality assurance of orthopaedic residency programs in Chile.

Effect of cyclic tension on the biomechanical properties of flexor tendon grafts. Results of an ex-vivo porcine study.

BACKGROUND: Autologous flexor tendons are widely used for anterior cruciate ligament (ACL) reconstruction. Pretension of the graft before fixation has been described as part of the surgical technique, nevertheless there is no consensus on the type and amount to tension needed to increase the stiffness without affecting its biomechanical properties.Our hypothesis is cyclic tension increases flexor tendon stiffness without affecting its ultimate failure at maximum loads (UFML). METHODS: Forty-five flexor digitorum profundus tendons harvested from domestic pigs (Sus scrofa domestica) were randomly divided into three groups: E1 (n=15), E2 (n=15) and C (n=15). Groups E1 and E2 were subjected to 50 cyclic loads at a 1 Hz frequency, at 70N and 100N respectively, group C was not intervened. The three groups were then tested for UFML. Cyclic loads and measurements were performed using a Stress-Strain machine (SST 1.0 Kinetecnic). Results were analyzed using GrapgPad statistical software. Groups were compared using Mann-Whitney test with a 95% confidence interval. RESULTS: Significant increased stiffness for group E1 (p=0.02) and group E2 ( p<0.01) when compared to group C. The stiffness of group E2 was also significantly higher than E1 (p=0.03). There was a significant reduction on the UFML between group E2 and C (p<0.01), which was not observed when comparing groups E1 and C. CONCLUSION: Cyclic loads at 70N result in an increased stiffness of flexor tendons without affecting its ultimate failure at maximum loads. Cyclic loads at higher tensions might cause a deleterious effect on the biomechanical properties of flexor tendon grafts.