The distance between the fibular collateral ligament tunnel and the common peroneal nerve allows a posterolateral corner reconstruction without neurolysis.

PURPOSE: The most popular knee posterolateral corner (PLC) reconstruction techniques describe that a common peroneal nerve (CPN) neurolysis must be done to safely address the posterolateral aspect of the knee. The purpose of this study was to measure the distance between the CPN and the fibular insertion of the FCL in different degrees of knee flexion in cadaveric specimens, to identify if tunnel drilling could be done anatomically and safely without a CPN neurolysis. METHODS: Ex vivo experimental analytical study. Ten fresh frozen human knees were dissected leaving FCL and CPN in situ. Shortest distance from the centre of the FCL distal tunnel and CPN was measured (antero-posterior and proximal-distal wire-nerve distances) at 90°, 60°, 30°, and 0° of knee flexion. Measurements between different flexion angles were compared and correlation between knee flexion angle and distance was identified. RESULTS: The mean distance between the FCL tunnel and the CPN at 90° were 21.15 ± 6.74 mm posteriorly (95% CI: 16.33-25.97) and 13.01 ± 3.55 mm distally (95% CI: 10.47-15.55). The minimum values were 9.8 mm posteriorly and 8.9 mm, respectively. These distances were smaller at 0° (p ≤ 0.017). At 90° of knee flexion, the mean distance from the fibular tip to the CPN distally was 23.46 ± 4.13 mm (20.51-26.41). CONCLUSION: Anatomic localization and orientation of fibular tunnels can be done safely while avoiding nerve neurolysis. Further studies should aim to in vivo measurements and results.

Mid and lower thoracic kyphosis changes during adulthood: the influence of age, sex and thoracic coronal curvature.

INTRODUCTION: There is conflicting data on how thoracic kyphosis changes throughout adulthood. We evaluated mid and lower thoracic kyphosis (MTK) in various age groups and the influence of age, sex and coronal curve (CC) on MTK. MATERIAL AND METHODS: We studied 1323 patients 15-80 years-old (54.4% females) previously evaluated with chest radiographs. We established three groups: patients 15-40 (group 1); 41-60 (group 2) and 61-80 years old (group 3). MTK (T5-T12) and CC were measured using Cobb's method. We established differences in MTK between groups using ANOVA with Bonferroni correction. We performed a correlation analysis of MTK with age and CC, and a linear regression analysis to determine if age, sex and CC independently predicted MTK. RESULTS: MTK increased with older age: mean MTK group 1 = 23.4°; group 2 = 27.9° and group 3 = 34.4°, p < 0.01. The increase in MTK was observed in both genders. Scoliosis was more common in females (15.4%) than in males (6.7%), p < 0.01. MTK was correlated with age (r = 0.4; p < 0.01) and slightly correlated with CC (r = 0.07, p < 0.01). MTK was larger in females than in males (29.1° vs. 27.6°, p < 0.01). Age (ß-coefficient = 0.26) and CC (ß-coefficient = 0.14), but not sex, independently influenced MTK in the regression analysis. CONCLUSION: MTK increases with advancing age during adulthood in both genders; CC, but not sex, was an independent predictor of MTK.

[Presence of women in medical publications in Chile]. / La mujer en las publicaciones científicas en Chile.

BACKGROUND: Despite recent initiatives and efforts, gender inequality still exists in medicine and academia. There is a higher proportion of male authors in international scientific publications. AIM: To compare the proportion of female and male authors in the scientific publications of the main medical journals in Chile. MATERIAL AND METHODS: We reviewed 1,643 Scientific articles published between 2015 and 2020 in two medical journals from Chile. Three authors analyzed the title, abstract, and authors of all published articles, recording the sex of the first author, co-authors, and corresponding author. RESULTS: The reviewed articles had a mean of 5.3 authors and there was a significant difference between men and women (a mean of 2.8 men and 2.4 women; p < 0.001). Forty-six percent (n = 761) of the articles had a female first author. In a higher proportion of papers, men completed both positions (1st and corresponding author) simultaneously. CONCLUSIONS: There are fewer female authors in scientific publications. Chile is one of the countries with a high rate of gender gap in the world. The underrepresentation of women in academia is an example of this.

The use of intraoperative comparative fluoroscopy allows for assessing sagittal reduction and predicting syndesmosis reduction in ankle fractures.

Intraoperative fluoroscopic parameters have shown to be poor predictors for ankle syndesmosis reduction, with up to 52% of syndesmotic malreduction (SMR) reported in the literature. Anteroposterior Tibio-Fibular index (APTF) was previously described to evaluate sagittal tibiofibular alignment in lateral ankle radiographs with a high correlation between both ankles in uninjured subjects. Reproducible intraoperative measurements for sagittal syndesmotic reduction are lacking. We propose the use of the "cAPTF," calculated as the absolute difference between the APTF of the non-injured and the operated ankle, to evaluate sagittal syndesmotic reduction. OBJECTIVE: Determine the predictive capability of cAPTF for SMR. METHOD: Prospective observational study. INCLUSION CRITERIA: patients with unstable ankle fractures requiring syndesmotic fixation, with a healthy contralateral ankle. Intraoperatively APTF was measured in both ankles after syndesmotic fixation. Postoperatively cAPTF was calculated. Only direct syndesmosis visualization through the lateral approach and AP and mortise views were used by surgeons to assess syndesmotic reduction. Quality of syndesmotic reduction was evaluated with bilateral postoperative CT. To estimate cAPTF discriminatory power for SMR, a receiver operative characteristic (ROC) curve was obtained and the area under the ROC curve was calculated. Youden index was used to determine the ideal cAPTF cut-off value for predicting SMR. For this determined cut-off value, sensitivity, specificity, and likelihood ratio were calculated. RESULTS: Fifty-two patients were included. Sixteen (30%) had SMR. Patients with SMR had a statistically significant higher cAPTF value than the well reduced (median 0.26 vs 0.09; P < 0.01). The cAPTF cut-off value to predict SMR was 0.161. A cAPTF greater than 0.161 had 100% sensitivity and 97,2% specificity for SMR. The area under the ROC curve was 0.99. CONCLUSION: Intraoperative cAPTF has excellent discriminatory power for predicting syndesmotic malreduction. We propose the routine use of intraoperative bilateral comparative fluoroscopy to assess sagittal syndesmotic reduction.

Anterior and distal tunnel orientation for anatomic reconstruction of the medial patellofemoral ligament is safer in patients with open growth plates.

PURPOSE: In patients with open growth plates, the direction of tunneling that avoids distal femoral physis (DFP) damage in anatomic reconstructions of the medial patellofemoral ligament (MPFL) has been a topic of discussion. The objective of this study was to determine the ideal orientation for anatomic reconstructions of MPFL tunneling that minimized DFP damage while avoiding breaching the intercondylar notch. METHODS: Eighty magnetic resonance images of patients aged 10 through 17 were obtained, randomly sampled from the institutional database. A de novo software was developed to obtain 3D models of the distal femur and DFP. In each model, the anatomical insertion point of the MPFL was determined as defined by Stephen. A 20-mm-depth drilling was simulated, starting from the insertion point at every possible angle within a 90° cone using 5-, 6- and 7-mm drills. Physeal damage for each pair of angles and each drill size was determined. Damage was expressed as a percentage of total physis volume. Statistical analysis was conducted using Student's t test and one-way ANOVA. RESULTS: Maximum physeal damage (5.35% [4.47-6.24]) was obtained with the 7-mm drill when drilling 3° cephalic and 15° posterior from insertion without differences between sexes (n.s.). Minimal physeal damage (0.22% [0.07-0.37]) was obtained using the 5-mm drill aimed 45° distal and 0° anteroposterior, not affected by sex (n.s.). Considering intra-articular drilling avoidance, the safest zone was obtained when aiming 30°-40° distal and 5°-35° anterior, regardless of sex. CONCLUSION: Ideal femoral tunnel orientation, avoiding physeal damage and breaching of the intercondylar notch, was obtained when aiming 30°-40° distal and 5°-35° anterior, regardless of sex. This area is a safe zone that allows anatomic MPFL reconstruction of patients with an open physis.

Scheuermann's disease in patients 15-40 years old: A study to determine its prevalence and its relationship with age and sex using chest radiographs as screening tool.

BACKGROUND: There is insufficient knowledge of the epidemiology of Scheuermann's disease. The data available comes from estimations from young adults with obvious deformity, from studies evaluating children who may not have developed the deformity yet, or from older populations who can develop vertebral wedging secondary to other causes. We aimed to determine the prevalence of Scheuermann's disease in patients 15-40 years old using plain chest radiographs as a screening tool. METHODS: We evaluated 454 patients aged 15-40 years old studied using standing plain chest radiographs. We measured thoracic kyphosis from T5 to T12; using the intraclass correlation coefficient (ICC), we determined inter- and intra-observer agreement. To determine the prevalence of Scheuermann's disease we used the Sorensen criteria. We performed a correlation analysis of thoracic kyphosis and age, and a linear regression to determine the impact of age and sex on the kyphosis angle. RESULTS: The prevalence of Scheuermann's disease was 2.2% (0.9-3.5%). The prevalence was not different in females (1.4%) and males (2.8%), p = 0.36. Inter-and intra-observer agreements were excellent: ICC = 0.93 (0.84-0.97) and 0.97 (0.95-0.98). There was a small positive correlation of kyphosis angle with age (r = 0.110; p = 0.019). Linear regression revealed that age (ß = 0.138; p = 0.019) was an independent predictor of kyphosis angle, but sex was not (ß-coefficient = 0.007; p = 0.994). CONCLUSION: We found a prevalence of Scheuermann's disease of 2.2%, without significant differences between males and females. Age independently influenced the kyphosis angle; sex did not. This study allows a better understanding of the epidemiology of Scheuermann's disease.

Incidental identification of vertebral compression fractures in patients over 60 years old using computed tomography scans showing the entire thoraco-lumbar spine.

INTRODUCTION: Vertebral compression fractures (VCF) are frequently asymptomatic; incidental diagnosis is a valuable opportunity to identify low bone mass and to start treatment. We aimed to determine the proportion of patients over 60 years old evaluated with chest plus abdominal and pelvic computed tomography (CT) scans, allowing visualization of the entire thoraco-lumbar spine, who incidentally present VCF. MATERIALS AND METHODS: We evaluated 300 patients over 60 years old who under went chest plus abdominal and pelvic CT scans. Using sagittal reformats we looked for VCF using the method described by Genant. Accordingly, VCF were classified into mild, moderate or severe. We also determined the percentage of VCF described in the radiological reports. RESULTS: In our cohort [median age 72.5 years (61-94)], 45.67% were males and 54.33% were females. In total, 43 patients (14.33%) had at least one VCF; 32 (10.67%) had one VCF, whereas 11 (3.67%) exhibited multiple VCF, with a total of 84 fractures. 42 were mild fractures, 29 moderate and 13 severe. The proportion of males (13.87%) and females (14.72%) with VCF was not different (p = 0.83). Patients with VCF were older than those without VCF (p < 0.01). Only age but not sex was independently associated with the presence of VCF. Only 32.56% of patients we identified as having a VCF had a description in their report (14 patients). CONCLUSION: An important proportion of patients over 60 years old evaluated with chest plus abdominal and pelvic CT scans present VCF. The reporting of these VCF is insufficient; radiologists and clinicians should include their detection in their search pattern.

Does the META score evaluating osteoporotic and metastatic vertebral fractures have enough agreement to be used by orthopaedic surgeons with different levels of training?

PURPOSE: Differentiating osteoporotic vertebral fractures (OVF) from metastatic vertebral fractures (MVF) is difficult. A magnetic resonance imaging (MRI)-based score (META score) aiming to differentiate OVF and MVF was recently published; however, an independent agreement assessment is required before the score is used. We performed such independent agreement evaluation, including raters with different levels of training. METHODS: Sixty-four patients with confirmed OVF or MVF were evaluated by six raters (three spine surgeons and three orthopaedic residents) using the META score. We used the intra-class correlation coefficient (ICC) to evaluate inter- and intra-observer agreement and the kappa statistic (κ) to determine the agreement for individual score criteria. We calculated the area under the receiver-operating characteristic curve (AUC) to establish the score accuracy. RESULTS: The inter-observer agreement was poor [ICC = 0.22 (0.12-0.33)]; spine surgeons [ICC = 0.75 (0.66-0.83)] had better agreement than that of residents [ICC = 0.06 (- 0.07 to 0.23)]. The intra-observer agreement was poor [ICC = 0.15 (- 0.04 to 0.30)]; both spine surgeons [ICC = 0.21 (0.05-0.41)] and residents exhibited poor agreement [ICC = - 0.06 (- 0.40 to 0.20)]. The agreement for each specific criterion varied from κ = 0.24 to κ = 0.38. The AUC was 0.57 (0.64 for spine surgeons and 0.51 for residents, p < 0.01). CONCLUSION: The inter-observer agreement using the META score was adequate for spine surgeons but not for residents; the intra-observer agreement was poor. These results do not support the standard use of the META score to differentiate OVF and MVF. These slides can be retrieved under Electronic Supplementary Material.

Is a single-level measurement of paraspinal muscle fat infiltration and cross-sectional area representative of the entire lumbar spine?

PURPOSE: Lumbar paraspinal muscle morphology has recently been evaluated in several studies with conflicting results. Several studies have performed single-slice evaluations of paraspinal muscle morphology, whereas other studies have done a multi-level assessment; this methodological difference might explain the observed different results. Our study evaluated if a single-slice axial measurement is representative of the entire lumbar musculature. METHODS: We included 80 adult patients who were consecutively evaluated with magnetic resonance imaging (MRI) for spinal symptoms. Using T2-weighted axial images, we measured the fat signal fractions (FSF) and cross-sectional area (CSA) of the erector spinae and multifidus at the five levels of the lumbar spine (from L1-L2 to L5-S1). We used the ANOVA test for repeated measurements (with Bonferroni correction) to compare the FSF and CSA among the levels. RESULTS: Erector spinae showed an increasing FSF from L1-L2 to L5-S1; all erector spinae FSF comparisons among the different levels were significantly different. Multifidus FSF also increased caudally below L2-L3, although significant differences were observed only with two or more levels of distance. The CSA of the erector spinae showed a caudal decrease (L4-L5 and L5-S1 being significantly smaller than all the levels above). The CSA of the multifidus showed that all levels exhibited a significantly different area compared to their adjacent level (except L5-S1 compared to L4-L5). CONCLUSIONS: No single-level FSF or CSA is representative of the whole lumbar spine. A standardized multi-level evaluation of the paraspinal musculature should be used in future research.

Lumbar paraspinal muscle fat infiltration is independently associated with sex, age, and inter-vertebral disc degeneration in symptomatic patients.

PURPOSE: To determine the association of paraspinal muscles and psoas relative cross-sectional area (RCSA) and fat signal fraction (FSF) with sex, age, and intervertebral disc degeneration (IDD) in symptomatic patients. METHODS: We retrospectively evaluated 80 adult patients with spinal symptoms using T2-weighted magnetic resonance images. We determined RCSA and FSF of the paraspinal muscles (erector spinae and multifidus) and psoas from L1-L2 to L5-S1; we determined IDD using the Pfirrmann classification. We compared differences in muscle RCSA and FSF based on sex and IDD, and we correlated age and IDD with RCSA and FSF. Using multivariate linear regression analyses, we determined the impact of sex, age, and IDD on RCSA and FSF. RESULTS: Men exhibited larger psoas RCSA but not larger paraspinal muscles RCSA than women. Women had larger FSF in the paraspinal muscles and psoas. Increasing IDD was associated with larger FSF if ≥2 Pfirrmann grades were observed. IDD correlated with FSF of the paraspinal muscles, and age correlated with FSF of the paraspinal muscles and psoas. IDD was less consistently correlated with RCSA, but age correlated negatively with RCSA of all three muscles. Linear regression analyses demonstrated that sex, age, and IDD were each independently associated with FSF of the paraspinal muscles; additionally, sex and age, but not IDD, were associated with psoas FSF. RCSA was less consistently influenced by these three variables. CONCLUSIONS: Sex, age, and IDD are independently associated with paraspinal muscles FSF; only sex and age influence psoas FSF.

The Pfirrmann classification of lumbar intervertebral disc degeneration: an independent inter- and intra-observer agreement assessment.

PURPOSE: Grading inter-vertebral disc degeneration (IDD) is important in the evaluation of many degenerative conditions, including patients with low back pain. Magnetic resonance imaging (MRI) is considered the best imaging instrument to evaluate IDD. The Pfirrmann classification is commonly used to grade IDD; the authors describing this classification showed an adequate agreement using it; however, there has been a paucity of independent agreement studies using this grading system. The aim of this study was to perform an independent inter- and intra-observer agreement study using the Pfirrmann classification. METHODS: T2-weighted sagittal images of 79 patients consecutively studied with lumbar spine MRI were classified using the Pfirrmann grading system by six evaluators (three spine surgeons and three radiologists). After a 6-week interval, the 79 cases were presented to the same evaluators in a random sequence for repeat evaluation. The intra-class correlation coefficient (ICC) and the weighted kappa (wκ) were used to determine the inter- and intra-observer agreement. RESULTS: The inter-observer agreement was excellent, with an ICC = 0.94 (0.93-0.95) and wκ = 0.83 (0.74-0.91). There were no differences between spine surgeons and radiologists. Likewise, there were no differences in agreement evaluating the different lumbar discs. Most differences among observers were only of one grade. Intra-observer agreement was also excellent with ICC = 0.86 (0.83-0.89) and wκ = 0.89 (0.85-0.93). CONCLUSIONS: In this independent study, the Pfirrmann classification demonstrated an adequate agreement among different observers and by the same observer on separate occasions. Furthermore, it allows communication between radiologists and spine surgeons.

Prevalence of lactose intolerance in Chile: a double-blind placebo study.

BACKGROUND AND STUDY AIMS: Lactase non-persistence (LNP), or primary hypolactasia, is a genetic condition that mediates lactose malabsorption and can cause lactose intolerance. Here we report the prevalence of lactose intolerance in a double-blind placebo study. METHODS: The LCT C>T-13910 variant was genotyped by RT-PCR in 121 volunteers and lactose malabsorption was assessed using the hydrogen breath test (HBT) after consuming 25 g of lactose. Lactose intolerance was assessed by scoring symptoms (SS) using a standardized questionnaire following challenge with a lactose solution or saccharose placebo. RESULTS: The LNP genotype was observed in 57% of the volunteers, among whom 87% were HBT⁺. In the HBT⁺ group the median SS was 9 and in the HBT⁻ group the median SS was 3 (p < 0.001). No difference was observed in the SS when both groups were challenged with the placebo. The most common symptoms included audible bowel sounds, abdominal pain and meteorism. In the ROC curve analysis, an SS ≥ 6 demonstrated 72% sensitivity and 81% specificity for predicting a positive HBT. To estimate prevalence, lactose intolerance was defined as the presence of an SS ≥ 6 points after subtracting the placebo effect and 34% of the study population met this definition. CONCLUSIONS: The LNP genotype was present in more than half of subjects evaluated and the observed prevalence of lactose intolerance was 34%.

Use of electromyographic biofeedback in rehabilitation following anterior cruciate ligament reconstruction: a systematic review and meta-analysis.

BACKGROUND: Rehabilitation following anterior cruciate ligament (ACL) reconstruction surgery is essential to regain functionality and return to previous activity level. Electromyographic biofeedback may be an effective intervention for rehabilitation of patients following ACL surgery. OBJECTIVE: To synthesize the available evidence on the effect of electromyographic biofeedback in the treatment of quadriceps strength following ACL surgery. DESIGN: Systematic review with meta-analysis. DATA SOURCES: PubMed, EMBASE, CENTRAL and Epistemonikos were searched. ELIGIBILITY CRITERIA: Randomized clinical trials with patients undergoing ACL reconstruction surgery comparing biofeedback with a standard rehabilitation control group. DATA EXTRACTION AND DATA SYNTHESIS: Two authors selected articles and performed data extraction. The analysed outcomes were strength, function, pain, knee extension and balance. The risk of bias of individual studies was assessed using the Cochrane Risk of Bias Tool. Results were combined through random-effects meta-analysis, reporting mean differences. RESULTS: Eight articles were included in the qualitative analysis, and four articles were included in the quantitative analysis. The interventions lasted between 4 and 12 weeks. Three studies evaluated the effect of biofeedback on quadriceps strength; of these, two studies showed a significant difference in favour of the biofeedback group. In addition, biofeedback was found to improve knee extension [standardized mean difference - 1.3, 95% confidence interval (CI) - 1.74 to -0.86] and balance (one study). There was no significant difference in Lysholm score (mean difference -6.21, 95% CI -17.51 to 5.08; I2 =59%) or pain between the biofeedback group and the control group. CONCLUSION: Electromyographic biofeedback in knee rehabilitation could be useful following ACL reconstruction surgery. KEY MESSAGES: SYSTEMATIC REVIEW REGISTRATION NUMBER: PROSPERO (CRD42020193768).

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.

Simulation-Based Training Program for Peripherally Inserted Central Catheter Placement: Randomized Comparative Study of in-Person Training With Synchronous Feedback Versus Distance Training With Asynchronous Feedback.

INTRODUCTION: Simulation training that includes deliberate practice is effective for procedural skill training. Delivering feedback remotely and asynchronously has been examined for more cost-efficient training. This prospective randomized study aimed to compare 2 feedback techniques for simulation training: synchronous direct feedback versus asynchronous distance feedback (ASYNC). METHODS: Forty anesthesia and internal medicine residents were recruited after study approval by the institutional ethics committee. Residents reviewed instructional material on an online platform and performed a pretraining assessment (PRE) for peripherally inserted central catheter (PICC) placement. Each resident was then randomly assigned to 1 of 2 training types, practice with synchronous direct feedback (SYNC) or practice with ASYNC. Training consisted of four, 1-hour practice sessions; each was conducted once per week. Both groups underwent posttraining evaluation (POST). The PRE and POST assessments were videotaped and evaluated by 2 independent, blinded reviewers using a global rating scale. RESULTS: Thirty-five residents completed the training program and both evaluations. Both groups had significantly improved global rating scale scores after 4 sessions. The SYNC group improved from 28 to 45 points (P < 0.01); the ASYNC group improved from 26.5 to 46 points (P < 0.01). We found no significant between-group differences for the PRE (P = 0.42) or POST assessments (P = 0.13). CONCLUSION: This simulation-based training program significantly improved residents' peripherally inserted central venous catheter placement skills using either modality. With these results, we are unable to demonstrate the superiority of synchronous feedback over ASYNC. Asynchronous feedback training modality represents a new, innovative approach for health care procedural skills training.

Tibial tubercle to trochlear groove and the roman arch method for tibial tubercle lateralisation are reliable and distinguish between subjects with and without major patellar instability.

PURPOSE: Patellofemoral (PF) instability recurrence depends on several factors including the relative lateralisation of tibial tubercle (TT) regarding the trochlear groove (TG). TT relative lateralisation quantification has long been a topic of debate. Multiple measuring techniques have been described including TT-trochlear groove (TT-TG), TT-posterior cruciate ligament (TT-PCL) and TT-roman arch (TT-RA), with no clear consensus regarding the most reliable index or pathologic threshold. We set out to determine the normal value range of each index and their association with age, sex and PF instability status. Also, this study aims to determine a reliable pathologic distance threshold to effectively predict patellar dislocation. METHODS: Skeletally mature patients up to 45 years of age who presented a CT Scan and an MRI of the same knee between 2014 and 2018 were included and divided into subgroups based on history of PF instability. Three indexes (TT-TG, TT-PCL and TT-RA) were assessed by two independent observers blinded to instability history. ROC curves were performed for each index to obtain the cut point that better predicts instability. Univariate and multivariate models adjusted by age, sex, instability history and type of imaging technique were performed to test the influence of these variables. RESULTS: 208 patients were included. Mean age was 27.93 â€‹± â€‹8.48 years, 67.3% were female and 71 patients (34.1%) presented major instability history. Good or excellent inter and intraobserver reliability was found for all three indexes. All indexes presented significantly different distributions between subjects with and without major instability (p â€‹< â€‹0.001), except for TT-PCL. Different cut point values differing between imaging modalities were found: 11.4 â€‹mm for MRI TT-TG, 17 â€‹mm for CT TT-TG, 15.6 â€‹mm for MRI TT-RA and 18.2 â€‹mm for CT TT-RA. CONCLUSIONS: All indexes studied had good or excellent inter and intraobserver reliability. Measurements between imaging techniques (CT and MR) are not interchangeable. Both TT-TG and TT-RA correctly distinguish between subjects with and without major instability, while TT-PCL does not, recommending caution when evaluated on its own. Specific threshold values depending on imaging technique should be considered for surgical decision-making. LEVEL OF EVIDENCE: Level IV, Diagnostic Test.

Skyline view of the patella does not increase fracture detection: A non-inferiority diagnostic study.

PURPOSE: Patella fractures are frequent injuries in the adult population. Initial study is made by plain radiographs and the standard set includes the skyline view of patella. Recommendation for use of this projection is variable among the experts, without data that support its performance in the diagnosis of patella fractures. The main purpose of this study was to determine the sensitivity of the antero-posterior and lateral view of the knee, without skyline view, in the diagnosis of patella fracture. METHODS: A retrospective non-inferiority diagnostic study was designed with all the knee trauma adult patients of an Emergency Department in a single center in five years. A random sample of all the consecutive patella fracture cases were taken to elaborate the case group. The control group was matched by sex and age. Two blinded orthopedic surgeons reviewed the cases and control radiographs and defined the presence of fracture, with or without skyline view, with a wash-out time of three weeks between the two evaluations. Non-inferiority was defined a priori at 90% of minimum sensitivity. RESULTS: 140 patients were evaluated (70 cases and 70 controls). Sensitivity of the set without skyline view was 92.86% (CI 95% 0.90 - 0.96) and the standard set was 97.86% (CI 95% 0.96 - 0.99), without significant differences (p = 0.1) CONCLUSION: Sensitivity of the plain radiograph set without skyline view is non-inferior to the standard set. The routine use of skyline view when suspecting patella fractures is questionable.

The AO classification system for tibial plateau fractures: An independent inter and intraobserver agreement study.

PURPOSE: Classifying tibial plateau fractures is paramount in determining treatment regimens and systemizing decision making. The original AO classification described by Müller in 1996 and the Schatzker classification of 1970 are the most cited classifications for tibial plateau fractures, demonstrating substantial to almost perfect agreement. The main problem with these classifications schemes is that they lack the detail required to convey the variety of fracture patterns encountered. In 2018, the AO foundation published a new classification system for proximal tibia fractures, highlighting a more complete and detailed number of categories and subcategories. We sought to independently determine inter and intraobserver agreement of the AO classification system, compared to the previous systems described by Müller and Schatzker. METHODS: One hundred seven consecutive tibial plateau fractures were screened, and a representative data set of 69 was created. Six independent evaluators (three knee surgeons, three senior orthopedic residents) classified the fractures using the original AO, the Schatzker and the new AO classifications. After six weeks, the 69 cases were randomized and reclassified by all evaluators. The Kappa coefficient (k) was calculated for inter- and intraobserver correlation and is expressed with 95% confidence intervals. RESULTS: interobserver agreement was moderate for all three classifications. k = 0.464 (0.383-0.560) for the original AO; k = 0.404 (0.337-0.489) for Schatzker; and k = 0.457 (0.371-0.545) for the base categories of the new AO classification. The inclusion of subcategories and letter modifiers to the new classification worsened agreement to k = 0.358 (0.302-0.423) and k = 0.174 (0.134-0.222), respectively. There were no significant differences between knee surgeons and residents for the new classification. Intra-observer correlation was also moderate for each of the scores: k = 0.630 (0.578-0.682) for the original AO; k = 0.623 (0.569-0.674) for Schatzker; and k = 0.621 (0.566-0.678) for the new AO base categories; without differences between knee surgeons or residents. CONCLUSIONS: This study demonstrated an adequate inter and intra-observer agreement for the new AO tibial plateau fractures classification system for its base categories, but not at the subcategory or letter modifier levels.

Tibial Cut Accuracy in Mechanically Aligned Total Knee Arthroplasty Using Extensor Hallucis Longus Tendon to Determine Extramedullary Tibial Guide Position.

This study aimed to determine the tibial cut (TC) accuracy using extensor hallucis longus (EHL) tendon as an anatomical landmark to position the total knee arthroplasty (TKA) extramedullary tibial guide (EMTG), and its impact on the TKA mechanical alignment (MA). We retrospectively studied 96 TKA, performed by a single surgeon, using a femoral tailored intramedullary guide technique. Seventeen were prior to the use of the EHL and 79 used the EHL tendon to position the EMTG. We analyzed preoperative and postoperative standing total lower extremity radiographs to determine the tibial component angle (TCA) and the correction in MA, comparing pre-EHL use and post-EHL technique incorporation. Mean TCA was 88.89 degrees and postoperative MA was neutral in 81% of patients. Pre- and postoperative MAs were not correlated. As a conclusion of this study, using the EHL provides a safe and easy way to determine the position of EMTG.

The new AO classification system for intertrochanteric fractures allows better agreement than the original AO classification. An inter- and intra-observer agreement evaluation.

BACKGROUND: A new AO classification for intertrochanteric fractures was recently published; no studies have evaluated its inter- and intra-observer agreement. METHODS: Six evaluators (three hip subspecialists and three residents) assessed radiographs of 68 intertrochanteric fractures; fractures were classified using the original and the new AO classifications. The cases were displayed in a random sequence after a six-week interval for repeat evaluation. We used the Kappa coefficient (k) to determine inter- and intra-observer agreement. RESULTS: Inter-observer agreement was slight (k = 0.128 [0.092-0.170]) using the original and fair (k = 0.250 [0.186-0.327]), with the new AO classification. Orthopedic residents exhibited better agreement than hip surgeons using the original classification (k = 0.302 [0.210-0.416] and k= -0.018 [-0.058-0.029], respectively) and the new classification (k = 0.388 [0.294-0.514] and k = 0.109 [0.031-0.192], respectively). Using both classifications as dichotomous variables (stable or unstable patterns), the agreement was slight (k = 0.158 [0.074-0.246]) using the original classification and moderate (k = 0.425 [0.308-0.550]) with the new AO classification. INTRA-OBSERVER: The agreement was fair using the original (k = 0.350 [0.278-0.424]) and the new (k = 0.295 [0.239 to 0.353]) AO classifications, respectively. Residents had better agreement than hip specialists using the original (k = 0.405 [0.303-0.512]) versus (k = 0.292 [0.193-0.293]) and the new classification (k = 0.449 [0.370 to 0.528] versus k = 0.129 [0.064 to 0.208]). CONCLUSION: The inter-observer agreement using the new AO classification was significantly better than using its original version. Also, the new AO classification system allowed better agreement when distinguishing stable from unstable patterns.