Early computational detection of potential high-risk SARS-CoV-2 variants.

The ongoing COVID-19 pandemic is leading to the discovery of hundreds of novel SARS-CoV-2 variants daily. While most variants do not impact the course of the pandemic, some variants pose an increased risk when the acquired mutations allow better evasion of antibody neutralisation or increased transmissibility. Early detection of such high-risk variants (HRVs) is paramount for the proper management of the pandemic. However, experimental assays to determine immune evasion and transmissibility characteristics of new variants are resource-intensive and time-consuming, potentially leading to delays in appropriate responses by decision makers. Presented herein is a novel in silico approach combining spike (S) protein structure modelling and large protein transformer language models on S protein sequences to accurately rank SARS-CoV-2 variants for immune escape and fitness potential. Both metrics were experimentally validated using in vitro pseudovirus-based neutralisation test and binding assays and were subsequently combined to explore the changing landscape of the pandemic and to create an automated Early Warning System (EWS) capable of evaluating new variants in minutes and risk-monitoring variant lineages in near real-time. The system accurately pinpoints the putatively dangerous variants by selecting on average less than 0.3% of the novel variants each week. The EWS flagged all 16 variants designated by the World Health Organization (WHO) as variants of interest (VOIs) if applicable or variants of concern (VOCs) otherwise with an average lead time of more than one and a half months ahead of their designation as such.

The structural basis of Cdc7-Dbf4 kinase dependent targeting and phosphorylation of the MCM2-7 double hexamer.

The controlled assembly of replication forks is critical for genome stability. The Dbf4-dependent Cdc7 kinase (DDK) initiates replisome assembly by phosphorylating the MCM2-7 replicative helicase at the N-terminal tails of Mcm2, Mcm4 and Mcm6. At present, it remains poorly understood how DDK docks onto the helicase and how the kinase targets distal Mcm subunits for phosphorylation. Using cryo-electron microscopy and biochemical analysis we discovered that an interaction between the HBRCT domain of Dbf4 with Mcm2 serves as an anchoring point, which supports binding of DDK across the MCM2-7 double-hexamer interface and phosphorylation of Mcm4 on the opposite hexamer. Moreover, a rotation of DDK along its anchoring point allows phosphorylation of Mcm2 and Mcm6. In summary, our work provides fundamental insights into DDK structure, control and selective activation of the MCM2-7 helicase during DNA replication. Importantly, these insights can be exploited for development of novel DDK inhibitors.

Good subjective outcome and low risk of revision surgery with a novel customized metal implant for focal femoral chondral lesions at a follow-up after a minimum of 5 years.

BACKGROUND AND PURPOSE: Patients with focal cartilage lesions experience functional impairment. Results for biological treatments in the middle-aged patient is poor. Previous studies with focal prosthetic inlay resurfacing have shown a higher risk of conversion to total knee replacement at mid-term follow-up. A novel customized implant (Episealer, Episurf, Stockholm, Sweden) has been proposed to improve implant positioning and survival. The primary objective was to assess subjective-, objective function and implant survival at a minimum of five years after surgery. MATERIALS AND METHODS: The inclusion criteria were patients aged 30-65 years with symptomatic focal chondral defects in the medial femoral condyle, International Cartilage Research Society grade 3 or 4 and failed conservative or surgical treatment. Minimum follow-up of 5 years. Clinical and radiologic assessments were made. Patient-reported outcome measurements at the latest follow-up were compared with the baseline data for the Knee injury and Osteoarthritis Outcome Score (KOOS), the EuroQoL (EQ-5D), the Tegner Activity Scale and a Visual Analog Scale of pain (VAS 0-10). RESULTS: Ten patients with the mean follow-up period of 75 months (60-86 months, SD 10) were included. Signs of osteoarthritis were seen in one patient (Ahlbäck 1). No cases with revision to knee replacement. VAS for pain and KOOS showed improvements that reached significance for VAS (p ≤ 0.001) and the KOOS subscores Pain (p = 0.01), ADL (p = 0.003), Sport and Recreation (p = 0.024) and Quality of Life (p = 0.003). CONCLUSION: A good subjective outcome, a low risk of progression to degenerative changes and the need for subsequent surgery were seen at the mid-term follow-up with this customized focal knee-resurfacing implant. LEVEL OF EVIDENCE: Prospective case series, level 4.

Successful Treatment of Femoral Chondral Lesions with a Novel Customized Metal Implant at Midterm Follow-Up.

BACKGROUND: Full-depth cartilage lesions do not heal spontaneously and may progress to osteoarthritis (OA). Treatment for these lesions is warranted when symptomatic. At younger age, biological treatment remains the gold standard, but treatment in the middle-aged patient remains a clinical challenge and focal metal implants have been proposed. We aim to present the subjective outcome at 2 years and the risk of reoperation for any reason at midterm after surgery with a novel customized implant for focal femoral chondral lesions in the knee. METHODS: In a prospective cohort study, 30 patients were included between January 2013 and December 2017 at 9 different clinics in Sweden. The primary outcome was subjective outcome measurements (Visual Analogue Scale [VAS], EuroQoL [EQ5D], Knee injury and Osteoarthritis Outcome Score [KOOS]) at a minimum of 2 years. The secondary outcome was reoperations for any reason during the follow-up period until December 2019 (mean of 55 months) studied retrospectively by analyzing medical records. RESULTS: The VAS, EQ5D, and all the KOOS subscales showed significant improvements from preoperatively to the 2-year follow-up. The VAS showed the greatest improvement at the early (3 months) postoperative stage (P < 0.001). Five (7%) patients underwent reoperations and one of these was revised to hemiarthroplasty due to OA progression. No implant loosening was detected in any of the cases. CONCLUSIONS: This customized resurfacing metal implant showed good safety and patient satisfaction. The risk of OA progression and implant loosening is low. Subjective function and pain improved significantly.

Younger age is associated with increased odds of manipulation under anesthesia for joint stiffness after total knee arthroplasty.

INTRODUCTION: Limited range of motion (ROM) after total knee replacement (TKR) is associated with low function and might require manipulation under anaesthesia (MUA). In order to identify factors associated with a limited ROM we investigated predictors for MUA. We hypothesized that older age was associated with higher MUA due to limited ROM post TKR. METHODS: In a case control study we investigated all patients undergoing primary TKR at a University Hospital in Sweden between 2007-2012. We registered background factors and compared those between the group who underwent MUA and those who did not. Odds ratios (OR) were calculated in a univariate analysis and an adjusted regression analysis. RESULTS: Of the total of 669 TKRs performed, 31 patients who had undergone MUA were identified. The prevalence of MUA was 4.6%. The mean increase in ROM after MUA was 27 degrees at final minimum one-year follow-up. After controlling for confounders, patients with good health and young age had increased OR for MUA. OR decreased 0.93 (CI 0.93-0.97) per increased age year in the multiple regression analysis. Diabetes mellitus, BMI and sex did not have a significant effect on the odds ratio for MUA. DISCUSSION: Young patients undergoing TKR has earlier been identified as a group with a higher grade of dissatisfaction and complications. We found an association between young age and MUA after TKR indicating an additional, rather unknown complication for this group of patients. The background and reasons for this has to be further investigated. LEVEL OF EVIDENCE: II, cohort study/case control study (case control is level III).

Cartilage Health in Knees Treated with Metal Resurfacing Implants or Untreated Focal Cartilage Lesions: A Preclinical Study in Sheep.

BACKGROUND: Full-depth cartilage lesions do not heal and the long-term clinical outcome is uncertain. In the symptomatic middle-aged (35-60 years) patient, treatment with metal implants has been proposed. However, the cartilage health surrounding these implants has not been thoroughly studied. Our objective was to evaluate the health of cartilage opposing and adjacent to metal resurfacing implants. METHODS: The medial femoral condyle was operated in 9 sheep bilaterally. A metallic resurfacing metallic implant was immediately inserted into an artificially created 7.5 mm defect while on the contralateral knee the defect was left untreated. Euthanasia was performed at 6 months. Six animals, of similar age and study duration, from a previous study were used for comparison in the evaluation of cartilage health adjacent to the implant. Cartilage damage to joint surfaces within the knee, cartilage repair of the defect, and cartilage adjacent to the implant was evaluated macroscopically and microscopically. RESULTS: Six animals available for evaluation of cartilage health within the knee showed a varying degree of cartilage damage with no statistical difference between defects treated with implants or left untreated ( P = 0.51; 95% CI -3.7 to 6.5). The cartilage adjacent to the implant (score 0-14; where 14 indicates no damage) remained healthy in these 6 animals showing promising results (averaged 10.5; range 9-11.5, SD 0.95). Cartilage defects did not heal in any case. CONCLUSION: Treatment of a critical size focal lesion with a metal implant is a viable alternative treatment.

No implant migration and good subjective outcome of a novel customized femoral resurfacing metal implant for focal chondral lesions.

PURPOSE: Managing focal cartilage injuries in the middle-aged patient poses a challenge. Focal prosthetic inlay resurfacing has been proposed to be a bridge between biologics and conventional joint arthroplasty. Patient selection and accurate implant positioning is crucial to avoid increased contact pressure to the opposite cartilage surface. A customized femoral condyle implant for focal cartilage injuries was designed to precisely fit each patient's individual size and location of damage. The primary objective was to assess implant safety profile, surgical usability of the implant and instruments, and implant migration with radiostereometric analysis (RSA). METHODS: Ten patients 36-56 years with focal chondral defects, ICRS 3-4 of the femoral cartilage and failed earlier conservative or surgical interventions with VAS pain > 40. The patients were followed for 2 years with subjective outcome measures (VAS, EQ5D, KOOS) and RSA. The customized implant and guide instruments were manufactured by computer-aided design/computer-aided manufacturing (CAD/CAM) techniques using MRI data. RESULTS: VAS, EQ5D and KOOS showed improvements that reached significance for VAS (p ≤ 0.001), Tegner (p = 0.034) and the KOOS subscores ADL (p = 0.0048), sport and recreation (p = 0.034) and quality of life (p = 0.037). VAS and KOOS scores improved gradually at 3, 6 and 12 months. The improvements in EQ5D, KOOS pain and KOOS symptoms did not reach statistical significance. No infections, deep venous thrombosis or other complications occured in the postoperative period. No radiographic signs of damage to the opposing tibial cartilage was noted. The surgical usability of implants and instruments were good. RSA did not show any implant migration. CONCLUSION: This is the first clinical report of a new customized, focal knee resurfacing system. The short-term implant safety and patient-related outcome measures showed good-to-excellent results. LEVEL OF EVIDENCE: Prospective case series, Level 4.

Eficacia predictiva de la resonancia magnética nuclear para diagnosticar el patrón de las lesiones completas del manguito rotador / Accuracy of magnetic resonance imaging to diagnose tear pattern of complete rotator cuff lesions

Introducción: la RMN ha demostrado influir significativamente en el diagnóstico del patrón de las lesiones completas del manguito rotador con una elevada sensibilidad y especificidad siendo el método complementario más utilizado. Nuestro objetivo es determinar la eficacia diagnóstica, y la variabilidad interobservador de la RMN para diagnosticar la forma de las lesiones completas del manguito rotador. Materiales y métodos: Se evaluaron 33 RMN de pacientes con rupturas completas de manguito rotador de manera prospectiva. Los patrones de lesiones analizados fueron crescéntica, L anterior, L posterior, lesión en U y masiva retraída. Dos especialistas en cirugía de hombro (O1 y O2) y el fellow de último año (O3) analizaron las RMN en días previos a la cirugía. Se utilizo el diagnostico artroscópico como gold standard y se calculó la concordancia entre las imágenes y la artroscopia con el índice kappa. Resultados: Para el diagnóstico del patrón de lesión obtuvo una concordancia excelente el O1, moderada el O3 y buena el O2. La ruptura crescéntica fue la mejor diagnosticada por los 3 observadores Conclusión: La RMN tiene una elevada sensibilidad y especificidad para el diagnóstico de los patrones de ruptura de manguito rotador teniendo relación con la experiencia de los observadores. Tipo de estudio: Prospectivo. Nivel de evidencia: I.

Introduction: MRI has been shown to have a significant influence on the diagnosis of complete rotator cuff tear pattern with an improved sensitivity and specificity being the most useful complementary method. Our purpose is to determine the accuracy and the interobserver variability of MRI to diagnose tear pattern of complete rotator cuff lesion. Methods: 33 patients MRI with complete rotator cuff tear were evaluated prospectively. The pattern lesions analyzed were crescent, anterior and posterior L shape tears, U pattern and massive tears. Two shoulder surgeons (O1 y O2) and one shoulder fellow (O3) analyzed the MRI´s days previous to surgery. The arthroscopic diagnosis was used as gold standard and the concordance between the images and arthroscopy was calculated with kappa index. Results: The concordance was excellent for observer 1, moderate for observer 3 and good for the observer 2 for the diagnosis of rotator cuff tear pattern. The crescent tear was the best diagnosed by the three observers. Conclusion: MRI has high sensitivity and specificity for the diagnosis of rotator cutt tear pattern in relation to the experience of the observers. Type of Study: Prospective. Level of Evidence: I.

Resultados de la reparación artroscópica de lesiones aisladas del subescapular: rol de la coracoplastía y manejo de la porción larga del bíceps / Arthroscopic repair of isolated subscapularis tendon tears. coracoplasty and management of long head biceps tendon

Objetivo: revisar sistemáticamente la bibliografía que reporten resultados de la reconstrucción artroscópica de las lesiones aisladas del tendón del subescapular con anclajes con súper-suturas; reportar el manejo del tendón del bíceps y la coracoides y evaluar la cicatrización del tendón al hueso mediante RNM. Material y Método: Realizamos una búsqueda sistemática de la literatura en ingles y español en las bases de datos de PubMed MEDLINE, EMBASE y LILACS mediante los términos de: Lesiones Aisladas del Subescapular y Reparación Artroscópica. Incluimos solo estudios que evalúan técnicas, resultados funcionales e imagenológico de lesiones aisladas del subescapular. Realizamos un análisis descriptivo de la bibliografía incluida. Resultados: Incluimos 7 artículos que cumplieron con los criterios de inclusión y exclusión. Los estudios incluidos se realizaron entre el 2003 y el 2013, con un total de 207 pacientes, 51 años de edad promedio. Las evaluaciones funcionales mejoraron significativamente al comparar los resultados pre y postoperatorios. La evaluación por RNM demostró alto índice de cicatrización con un bajo índice de re-ruptura. Las complicaciones fueron infrecuentes. Conclusión: Nuestra revisión sistemática demuestra que la reconstrucción artroscópica de las lesiones aisladas del tendón del subescapular es una buena opción de tratamiento con buenos resultados clínicos funcionales, buena integridad del tendón al hueso y un bajo índice de complicaciones. El bajo nivel de evidencia científica de la bibliografía demuestra la necesidad de realizar estudios prospectivos comparativos para obtener resultados de mayor poder estadístico. Nivel de Evidencia: IV. Tipo de estudio: Revisión sistemática de estudios

Purpose: to systematically review the literature to identify all studies reporting outcomes of arthroscopically repaired isolated subscapular tendon tears, the frequency and management of associated long head of biceps pathology, and the MRI integrity of subscapular tendon reconstruction. Methods: A systematic literature review in spanish and english language using the PubMed MEDLINE, EMBASE y LILACS databases with the term of: "Arthroscopic reconstruction of isolated subscapular tendon tears". Only studies evaluating the techniques, outcomes and MRI integrity of the reconstruction of isolated subscapularis repair were included. Descriptive analysis was provided for the available literature. Results: Seven studies were included in this review. The studies were done in between 2003 to 2013, 207 patients with 51 mean age. Uniformly, improvements in patient-reported outcome scores were substantial after arthroscopic subscapularis repair. Excellent MRI tendon to bone to integrity with very low complication rate. Conclusions: Arthroscopic subscapularis repair is a reasonable option to treat isolated tears of the subscapularis tendon to obtain successful functional outcomes. We need future prospective comparative studies. Level of Evidence: IV. Type of study: Systematic review of studies

Tratamiento artroscopico en condromatosis sinovial primaria de hombro y corredera bicipital. reporte de un caso / Arthroscopic treatment for synovial chondromatosis of the shoulder. case report

La condromatosis sinovial es una entidad patológica poco frecuente donde se desarrollan cuerpos de aspectos cartilaginosos a partir de la membrana sinovial de articulaciones, bursas o vainas tendinosas, generando cuerpos libres productores de la sintomatología. Presentamos un caso de 16 años que consulta con dolor de hombro derecho, progresivo sin antecedente de trauma previo, de 3 años de evolución. Se realizan estudios imagenológicos correspondientes llegando a la conclusión diagnostica de condromatosis sinovial de hombro. Se realiza el tratamiento quirúrgico definitivo por artroscopía, logrando remisión de los síntomas y evolución favorable sin recidiva hasta los 5 años de evolucion.

Synovial chondromatosis is a rare pathological entity where cartilaginous aspects develop from the synovial membrane of joints, bursae or tendinous sheaths, generating free bodies that produce symptoms. We present a 16-year-old male with 3 years of right shoulder pain, progressive with not previous trauma. Imaging studies are carried out, arriving at the diagnostic of synovial chondromatosis of the shoulder. The final surgical treatment is performed by arthroscopy, achieving remission of symptoms and favorable evolution without recurrence until 5 years of evolution.

Reconstrucción artroscópica del manguito rotador. Resultados funcionales a largo plazo. Estudio de base de datos prospectiva / Rotator cuff arthroscopic reconstruction. Long-term outcome results

Introducción: En nuestro medio existe poca evidencia científica de seguimiento a largo plazo en la reconstrucción artroscópica del manguito rotador. Objetivo: evaluar resultados funcionales de la reparación artroscópica del manguito rotador con un seguimiento promedio de 81 meses. Material y Método: realizamos 158 reparaciones artroscópica de manguito rotador. Setenta y seis hombros de 58 años promedio cumplieron los criterios de inclusión. Seguimiento promedio de 81 meses (60 – 96 meses) con registro en base de dato prospectiva digital detallando examen físico, score funcionales Simple Shoulder Test (SST), Constant abreviado y American Shoulder and Elbow Surgeons (ASES). Dividimos las lesiones en dos grupos, lesiones parciales, 9 casos, y lesiones completas, 67 casos divididas en 3 sub grupos: lesiones pequeñas y medianas (< 3 cm), grandes (3-5 cm) y masivas (> 5 cm). Resultados: con un seguimiento promedio de 81 meses, 95% de los pacientes tuvieron entre buenos y excelentes resultados con score de Constant, 65 ptes excelente (85%), 8 bueno (10%) y 3 regulares (5%), ningún resultado pobre. Con score de ASES y SST también observamos mejoría notable y persistente a lo largo del seguimiento en los pacientes, demostrando con el Test de Wilcoxon una p extremadamente significativa p:0,0001. En las Lesiones Parciales todos los resultados fueron excelentes y buenos. Aplicando el test de Mann Whitney obtuvimos una P < 0,05 en los tres scores. En Lesiones Completas, el Score de Constant abreviado el 95% de los resultados a 81 meses fueron entre buenos y excelentes. La distribución fue de 65 casos excelentes (85%), 8 buenos (10%), 3 regulares (5%) y ningún resultado pobre. Tanto en el SST, como en el score de ASES se observo también una mejoría notable y persistente en el seguimiento a largo plazo. Quedando demostrado con el Test de Wilcoxon que la diferencia fue extremadamente significativa con un valor p=0,0001 en los tres scores funcionales evaluados. Discusión: vemos resultados favorables, estadísticamente significativos al comparar diferentes scores funcionales de ASES, SST y Constant entre el pre quirúrgico con el seguimiento a largo plazo; con un 95% de buenos a excelentes resultados en la reparación artroscópica de las distintas lesiones en el manguito rotador. Nivel de evidencia: IV. Tipo de estudio: Estudio Terapéutico. Serie de Casos

Introduction: In spanish literature, there is little scientific evidence of long-term follow up for arthroscopic rotator cuff reconstruction. Purpose: to evaluate functional outcomes of arthroscopic rotator cuff repair with a mean follow of 81 months. Method: we performed 158 arthroscopic rotator cuff repairs. Seventy-six shoulders average of 58 years met the inclusion criteria. Average follow-up of 81 months (60-96 months) with digital prospective data based detailing physical exam, functional score with Simple Shoulder Test (SST), Constant and American Shoulder and Elbow Surgeons (ASES) score. We divided the lesions into two groups, partial lesions, 9 cases, and complete lesions, 67 cases divided into 3 sub groups: small and medium lesions (< 3 cm), large (3-5 cm) and massive (> 5 cm). Results: after a mean follow-up of 81 months ninety-five percent of patients had good to excellent results with Constant score, 65 ptes excellent (85%), 8 good (10%) and 3 regular (5%) no poor result. With ASES score and SST also observed significant and persistent improvement during follow-up, demonstrating with Wilcoxon test an extremely significant p=0.0001. All Partial lesions have excellent and good results, Applying Mann Whitney test we obtained a P <0.05 in all three scores. In Complete lesions the Constant Score was 95% of good to excellent results at 81 months average follow up. The distribution was: Excellent 65 cases (85%), 8 good (10%), 3 regular (5%) and no poor results. With SST and ASES score we had a significant and persistent improvement in long-term follow up. Being demonstrated with the Wilcoxon test that the difference was highly significant with a P value 0.0001 in the three evaluated functional scores. Discussion: we had statistically significant results when comparing different functional scores of ASES, SST and Constant between surgical pre preoperative score and the long-term follow up with 95% good to excellent results in arthroscopic repair of different rotator cuff lesions. Level of evidence: IV. Type of Study: Therapeutic Study. Cases Series

Reconstrucción artroscópica del manguito rotador. Resultados funcionales a largo plazo. Estudio de base de datos prospectiva / Rotator cuff arthroscopic reconstruction. Long-term outcome results

Introducción: En nuestro medio existe poca evidencia científica de seguimiento a largo plazo en la reconstrucción artroscópica del manguito rotador. Objetivo: evaluar resultados funcionales de la reparación artroscópica del manguito rotador con un seguimiento promedio de 81 meses. Material y Método: realizamos 158 reparaciones artroscópica de manguito rotador. Setenta y seis hombros de 58 años promedio cumplieron los criterios de inclusión. Seguimiento promedio de 81 meses (60 û 96 meses) con registro en base de dato prospectiva digital detallando examen físico, score funcionales Simple Shoulder Test (SST), Constant abreviado y American Shoulder and Elbow Surgeons (ASES). Dividimos las lesiones en dos grupos, lesiones parciales, 9 casos, y lesiones completas, 67 casos divididas en 3 sub grupos: lesiones pequeñas y medianas (< 3 cm), grandes (3-5 cm) y masivas (> 5 cm). Resultados: con un seguimiento promedio de 81 meses, 95% de los pacientes tuvieron entre buenos y excelentes resultados con score de Constant, 65 ptes excelente (85%), 8 bueno (10%) y 3 regulares (5%), ningún resultado pobre. Con score de ASES y SST también observamos mejoría notable y persistente a lo largo del seguimiento en los pacientes, demostrando con el Test de Wilcoxon una p extremadamente significativa p:0,0001. En las Lesiones Parciales todos los resultados fueron excelentes y buenos. Aplicando el test de Mann Whitney obtuvimos una P < 0,05 en los tres scores. En Lesiones Completas, el Score de Constant abreviado el 95% de los resultados a 81 meses fueron entre buenos y excelentes. La distribución fue de 65 casos excelentes (85%), 8 buenos (10%), 3 regulares (5%) y ningún resultado pobre. Tanto en el SST, como en el score de ASES se observo también una mejoría notable y persistente en el seguimiento a largo plazo. Quedando demostrado con el Test de Wilcoxon que la diferencia fue extremadamente significativa con un valor p=0,0001 en los tres scores funcionales evaluados. Discusión: vemos resultados favorables, estadísticamente significativos al comparar diferentes scores funcionales de ASES, SST y Constant entre el pre quirúrgico con el seguimiento a largo plazo; con un 95% de buenos a excelentes resultados en la reparación artroscópica de las distintas lesiones en el manguito rotador. Nivel de evidencia: IV. Tipo de estudio: Estudio Terapéutico. Serie de Casos(AU)

Introduction: In spanish literature, there is little scientific evidence of long-term follow up for arthroscopic rotator cuff reconstruction. Purpose: to evaluate functional outcomes of arthroscopic rotator cuff repair with a mean follow of 81 months. Method: we performed 158 arthroscopic rotator cuff repairs. Seventy-six shoulders average of 58 years met the inclusion criteria. Average follow-up of 81 months (60-96 months) with digital prospective data based detailing physical exam, functional score with Simple Shoulder Test (SST), Constant and American Shoulder and Elbow Surgeons (ASES) score. We divided the lesions into two groups, partial lesions, 9 cases, and complete lesions, 67 cases divided into 3 sub groups: small and medium lesions (< 3 cm), large (3-5 cm) and massive (> 5 cm). Results: after a mean follow-up of 81 months ninety-five percent of patients had good to excellent results with Constant score, 65 ptes excellent (85%), 8 good (10%) and 3 regular (5%) no poor result. With ASES score and SST also observed significant and persistent improvement during follow-up, demonstrating with Wilcoxon test an extremely significant p=0.0001. All Partial lesions have excellent and good results, Applying Mann Whitney test we obtained a P <0.05 in all three scores. In Complete lesions the Constant Score was 95% of good to excellent results at 81 months average follow up. The distribution was: Excellent 65 cases (85%), 8 good (10%), 3 regular (5%) and no poor results. With SST and ASES score we had a significant and persistent improvement in long-term follow up. Being demonstrated with the Wilcoxon test that the difference was highly significant with a P value 0.0001 in the three evaluated functional scores. Discussion: we had statistically significant results when comparing different functional scores of ASES, SST and Constant between surgical pre preoperative score and the long-term follow up with 95% good to excellent results in arthroscopic repair of different rotator cuff lesions. Level of evidence: IV. Type of Study: Therapeutic Study. Cases Series(AU)

Measurement of the migration of a focal knee resurfacing implant with radiostereometry.

BACKGROUND AND PURPOSE: Articular resurfacing metal implants have been developed to treat full-thickness localized articular cartilage defects. Evaluation of the fixation of these devices is mandatory. Standard radiostereometry (RSA) is a validated method for evaluation of prosthetic migration, but it requires that tantalum beads are inserted into the implant. For technical reasons, this is not possible for focal articular resurfacing components. In this study, we therefore modified the tip of an articular knee implant and used it as a marker for RSA, and then validated the method. MATERIAL AND METHODS: We modified the tip of a resurfacing component into a hemisphere with a radius of 3 mm, marked it with a 1.0-mm tantalum marker, and implanted it into a sawbone marked with 6 tantalum beads. Point-motion RSA of the "hemisphere bead" using standard automated RSA as the gold standard was compared to manual measurement of the tip hemisphere. 20 repeated stereograms with gradual shifts of position of the specimen between each double exposure were used for the analysis. The tip motion was compared to the point motion of the hemisphere bead to determine the accuracy and precision. RESULTS: The accuracy of the manual tip hemisphere method was 0.08-0.19 mm and the precision ranged from 0.12 mm to 0.33 mm. INTERPRETATION: The accuracy and precision for translations is acceptable when using a small hemisphere at the tip of a focal articular knee resurfacing implant instead of tantalum marker beads. Rotations of the implant cannot be evaluated. The method is accurate and precise enough to allow detection of relevant migration, and it will be used for future clinical trials with the new implant.

Análisis de variabilidad inter e intra-observador en el diagnóstico artroscópico de lesión de SLAP / Evaluation of the intra and inter-observer variability for arthroscopic diagnosis of SLAP lesion

Introducción: La lesión de SLAP se encuentra en permanente estudio en todos sus aspectos. La tendencia actual en su diagnóstico es considerar fundamentalmente la evaluación artroscópica. Nuestro objetivo es evaluar la variabilidad intra e inter-observador en el diagnóstico artroscópico de la lesión de SLAP utilizando la clasificación de Snyder. Material y Método: 27 videos pertenecientes a pacientes con patología de SLAP fueron editados, mostrando la fase diagnóstica de la artroscopía de hombro, y enviados a 4 cirujanos ortopedistas especializados en artroscopía, a quienes se les solicitó determinar un diagnóstico respecto al labrum superior de acuerdo a la clasificación de Snyder. Finalmente, se obtuvo la variabilidad diagnóstica intra e inter-observador utilizando para ello el porcentaje de concordancia así como el coeficiente Kappa. Resultado: se analizaron 216 respuestas, entre los cirujanos con más de 5 años de experiencia obtuvimos una concordancia diagnóstica inter-observador (k) casi perfecto, mientras que respecto a los datos obtenidos de los fellowship resultó en una variabilidad moderada. En ambos grupos la mayor discordancia se encontró en las Lesiones SLAP Tipo I, con marcada diferencia respecto al resto, siendo en su mayoría sobre-diagnosticadas como lesiones Tipo II. Conclusión: Podemos decir que la variabilidad en el diagnóstico artroscópico tanto inter como intra-observador de la lesión SLAP disminuye considerablemente cuanto mayor experiencia posea el observador

Análisis de variabilidad inter e intra-observador en el diagnóstico artroscópico de lesión de SLAP / Evaluation of the intra and inter-observer variability for arthroscopic diagnosis of SLAP lesion

Introducción: La lesión de SLAP se encuentra en permanente estudio en todos sus aspectos. La tendencia actual en su diagnóstico es considerar fundamentalmente la evaluación artroscópica. Nuestro objetivo es evaluar la variabilidad intra e inter-observador en el diagnóstico artroscópico de la lesión de SLAP utilizando la clasificación de Snyder. Material y Método: 27 videos pertenecientes a pacientes con patología de SLAP fueron editados, mostrando la fase diagnóstica de la artroscopía de hombro, y enviados a 4 cirujanos ortopedistas especializados en artroscopía, a quienes se les solicitó determinar un diagnóstico respecto al labrum superior de acuerdo a la clasificación de Snyder. Finalmente, se obtuvo la variabilidad diagnóstica intra e inter-observador utilizando para ello el porcentaje de concordancia así como el coeficiente Kappa. Resultado: se analizaron 216 respuestas, entre los cirujanos con más de 5 años de experiencia obtuvimos una concordancia diagnóstica inter-observador (k) casi perfecto, mientras que respecto a los datos obtenidos de los fellowship resultó en una variabilidad moderada. En ambos grupos la mayor discordancia se encontró en las Lesiones SLAP Tipo I, con marcada diferencia respecto al resto, siendo en su mayoría sobre-diagnosticadas como lesiones Tipo II. Conclusión: Podemos decir que la variabilidad en el diagnóstico artroscópico tanto inter como intra-observador de la lesión SLAP disminuye considerablemente cuanto mayor experiencia posea el observador (AU)

Deviation between navigated and final 3-dimensional implant position in mini-invasive unicompartmental knee arthroplasty: a pilot study in 13 patients.

BACKGROUND AND PURPOSE: Unicompartmental knee arthroplasty (UKA) is an established method of treating isolated gonartrosis. Modern techniques such as computer-assisted surgery (CAS) and minimally invasive surgery (MIS) are attractive complementary methods to UKA. However, the positioning of the components remains a concern. Thus, we performed a prospective study to assess whether there was deviation between the navigated implant position and the final implant position. PATIENTS AND METHODS: We performed UKA with MIS and CAS in 13 patients. By comparing intraoperative navigation data with postoperative computed tomography (CT) measurements, we calculated the deviation between the computer-assisted implant position and the final 3-D implant position of the femoral and tibial components. RESULTS: The computer-assisted placement of the femoral and tibial component showed adequate position and consistent results regarding flexion-extension and varus-valgus. However, regarding rotation there was a large variation and 6 of 10 patients were outside the target range for both the femoral component and the tibial component. INTERPRETATION: Difficulties in assessing anatomical landmarks with the CAS in combination with MIS might be a reason for the poor rotational alignment of the components.