Magnetic resonance imaging-based three-dimensional bone shape of the knee predicts onset of knee osteoarthritis: data from the osteoarthritis initiative.

OBJECTIVE: To examine whether magnetic resonance imaging (MRI)-based 3-dimensional (3-D) bone shape predicts the onset of radiographic knee osteoarthritis (OA). METHODS: We conducted a case-control study using data from the Osteoarthritis Initiative by identifying knees that developed incident tibiofemoral radiographic knee OA (case knees) during followup, and matching them each to 2 random control knees. Using knee MRIs, we performed active appearance modeling of the femur, tibia, and patella and linear discriminant analysis to identify vectors that best classified knees with OA versus those without OA. Vectors were scaled such that -1 and +1 represented the mean non-OA and mean OA shapes, respectively. We examined the relation of 3-D bone shape to incident OA (new-onset Kellgren and Lawrence [K/L] grade ≥2) occurring 12 months later using conditional logistic regression. RESULTS: A total of 178 case knees (incident OA) were matched to 353 control knees. The whole joint (i.e., tibia, femur, and patella) 3-D bone shape vector had the strongest magnitude of effect, with knees in the highest tertile having a 3.0 times higher likelihood of developing incident radiographic knee OA 12 months later compared with those in the lowest tertile (95% confidence interval [95% CI] 1.8-5.0, P < 0.0001). The associations were even stronger among knees that had completely normal radiographs before incidence (K/L grade of 0) (odds ratio 12.5 [95% CI 4.0-39.3]). Bone shape at baseline, often several years before incidence, predicted later OA. CONCLUSION: MRI-based 3-D bone shape predicted the later onset of radiographic OA. Further study is warranted to determine whether such methods can detect treatment effects in trials and provide insight into the pathophysiology of OA development.

Numerical study of osteophyte effects on preoperative knee functionality in patients undergoing total knee arthroplasty.

Osteophytes are routinely removed during total knee arthroplasty, yet the preoperative planning currently relies on preoperative computed tomography (CT) scans of the patient's osteoarthritic knee, typically including osteophytic features. This complicates the surgeon's ability to anticipate the exact biomechanical effects of osteophytes and the consequences of their removal before the operation. The aim of this study was to investigate the effect of osteophytes on ligament strains and kinematics, and ascertain whether the osteophyte volume and location determine the extent of this effect. We segmented preoperative CT scans of 21 patients, featuring different osteophyte severity, using image-based active appearance models trained to identify the osteophytic and preosteophytic bone geometries and estimate the cartilage thickness in the segmented surfaces. The patients' morphologies were used to scale a template musculoskeletal knee model. Osteophytes induced clinically relevant changes to the knee's functional behavior, but these were variable and patient-specific. Generally, severe osteophytic knees significantly strained the oblique popliteal ligament (OPL) and posterior capsule (PC) relative to the preosteophytic state. Furthermore, there was a marked effect on the lateral collateral ligament and anterolateral ligament (ALL) strains compared to mild and moderate osteophytic knees, and concurrent alterations in the tibial lateral-medial translation and external-internal rotation. We found a strong correlation between the OPL, PC, and ALL strains and posterolateral condylar and tibial osteophytes, respectively. Our findings may have implications for the preoperative planning in total knee arthroplasty, toward reproducing the physiological knee biomechanics as close as feasibly possible.

Pre-Planning the Surgical Target for Optimal Implant Positioning in Robotic-Assisted Total Knee Arthroplasty.

Robotic-assisted total knee arthroplasty can attain highly accurate implantation. However, the target for optimal positioning of the components remains debatable. One of the proposed targets is to recreate the functional status of the pre-diseased knee. The aim of this study was to demonstrate the feasibility of reproducing the pre-diseased kinematics and strains of the ligaments and, subsequently, use that information to optimize the position of the femoral and tibial components. For this purpose, we segmented the pre-operative computed tomography of one patient with knee osteoarthritis using an image-based statistical shape model and built a patient-specific musculoskeletal model of the pre-diseased knee. This model was initially implanted with a cruciate-retaining total knee system according to mechanical alignment principles; and an optimization algorithm was then configured seeking the optimal position of the components that minimized the root-mean-square deviation between the pre-diseased and post-operative kinematics and/or ligament strains. With concurrent optimization for kinematics and ligament strains, we managed to reduce the deviations from 2.4 ± 1.4 mm (translations) and 2.7 ± 0.7° (rotations) with mechanical alignment to 1.1 ± 0.5 mm and 1.1 ± 0.6°, and the strains from 6.5% to lower than 3.2% over all the ligaments. These findings confirm that adjusting the implant position from the initial plan allows for a closer match with the pre-diseased biomechanical situation, which can be utilized to optimize the pre-planning of robotic-assisted surgery.

Twelve tips for facilitating successful teleconferences.

BACKGROUND: The work of medical education is increasingly collaborative across geographical sites, sometimes spanning international borders. The success of projects depends more strongly on how meetings are led and run than variables about the task itself; therefore, excellent communication using teleconferencing technology is required. However, we found no medical literature to assist with developing best practices in telecommunication. AIM: Using the organization and management literature, which has examined the use of telecommunication in optimizing work outcomes, we provide a guide for initiating and facilitating teleconferences. METHODS: We used Tuckman's framework for group development as a means of organizing guidelines that address practical issues in approaching communication on teleconferences and discuss important aspects of forming work groups using telecommunication, setting ground rules and norms, addressing conflict, and enhancing accountability and outcomes. RESULTS: We identified 12 tips for optimal teleconferencing and divided them into phases of formation, setting ground rules, managing conflict, and enhancing group performance. CONCLUSION: Successful work on teleconferences requires excellent attention to the group process, especially since full engagement by participants is not always assured.

How Does Robotic-Arm Assisted Technology Influence Total Knee Arthroplasty Implant Placement for Surgeons in Fellowship Training?

Implant malalignment during total knee arthroplasty (TKA) may lead to suboptimal postoperative outcomes. Accuracy studies are typically performed with experienced surgeons; however, it is important to study less experienced surgeons when considering teaching hospitals where younger surgeons operate. Therefore, this study assessed whether robotic-arm assisted TKA (RATKA) allowed for more accurate and precise implant position to plan when compared with manual techniques when the surgery is performed by in-training orthopaedic surgical fellows. Two surgeons, currently in their fellowship training and having minimal RATKA experience, performed a total of six manual TKA (MTKA) and six RATKAs on paired cadaver knees. Computed tomography scans were obtained for each knee pre- and postoperatively. These scans were analyzed using a custom autosegmentation and autoregistration process to compare postoperative implant position with the preoperative planned position. Mean system errors and standard deviations were compared between RATKA and MTKA for the femoral component for sagittal, coronal, and axial planes and for the tibial component in the sagittal and coronal planes. A 2-Variance testing was performed using an α = 0.05. Although not statistically significant, RATKA was found to have greater accuracy and precision to plan than MTKA for: femoral axial plane (1.1° ± 1.1° vs. 1.6° ± 1.3°), coronal plane (0.9° ± 0.7° vs. 2.2° ± 1.0°), femoral sagittal plane (1.5° ± 1.3° vs. 3.1° ± 2.1°), tibial coronal plane (0.9° ± 0.5° vs. 1.9° ± 1.3°), and tibial sagittal plane (1.7° ± 2.6° vs. 4.7° ± 4.1°). There were no statistical differences between surgical groups or between the two surgeons performing the cases. With limited RATKA experience, fellows showed increased accuracy and precision to plan for femoral and tibial implant positions. Furthermore, these results were comparable to what has been reported for an experienced surgeon performing RATKA.

Impact of an in-person versus web-based practice standardized patient examination on student performance on a subsequent high-stakes standardized patient examination.

BACKGROUND: Optimal methods of preparing students for high-stakes standardized patient (SP) examinations are unknown. PURPOSES: The purpose is to compare the impact of two formats of a formative SP examination (Web-based vs. in-person) on scores on a subsequent high-stakes SP examination and to compare students' satisfaction with each formative examination format. METHODS: Clustered randomized trial comparing a Web-based module versus in-person formative SP examination. We compared scores on a subsequent high-stakes SP examination and satisfaction. RESULTS: Scores on the subsequent high-stakes SP examination did not differ between the two formative formats but were higher after the formative assessment than without (p < .001). Satisfaction was higher with the in-person than Web-based formative assessment format (4.00 vs. 3.62 on a 5-point scale, p = .01). CONCLUSIONS: Two formats of a formative SP examination led to equivalent improvement in scores on a subsequent high-stakes examination. Students preferred an in-person formative examination to online but were satisfied with both.

Applying innovative educational principles when classes grow and resources are limited: Biochemistry experiences at Muhimbili University of Allied Health Sciences.

Teaching to large classes is often challenging particularly when the faculty and teaching resources are limited. Innovative, less staff intensive ways need to be explored to enhance teaching and to engage students. We describe our experience teaching biochemistry to 350 students at Muhimbili University of Health and Allied Sciences (MUHAS) under severe resource limitations and highlight our efforts to enhance the teaching effectiveness. We focus on peer assisted learning and present three pilot initiatives that we developed to supplement teaching and facilitate student interaction within the classroom. These included; instructor-facilitated small group activities within large group settings, peer-led tutorials to provide supplemental teaching and peer-assisted instruction in IT skills to enable access to online biochemistry learning resources. All our efforts were practical, low cost and well received by our learners. They may be applied in many different settings where faculties face similar challenges.

Educational technology infrastructure and services in North American medical schools.

PURPOSE: To describe the current educational technology infrastructure and services provided by North American allopathic medical schools that are members of the Association of American Medical Colleges (AAMC), to present information needed for institutional benchmarking. METHOD: A Web-based survey instrument was developed and administered in the fall of 2004 by the authors, sent to representatives of 137 medical schools and completed by representatives of 88, a response rate of 64%. Schools were given scores for infrastructure and services provided. Data were analyzed with one-way analyses of variance, chi-square, and correlation coefficients. RESULTS: There was no difference in the number of infrastructure features or services offered based on region of the country, public versus private schools, or size of graduating class. Schools implemented 3.0 (SD = 1.5) of 6 infrastructure items and offered 11.6 (SD = 4.1) of 22 services. Over 90% of schools had wireless access (97%), used online course materials for undergraduate medical education (97%), course management system for graduate medical education (95%) and online teaching evaluations (90%). Use of services differed across the undergraduate, graduate, and continuing medical education continuum. Outside of e-portfolios for undergraduates, the least-offered services were for services to graduate and continuing medical education. CONCLUSIONS: The results of this survey provide a benchmark for the level of services and infrastructure currently supporting educational technology by AAMC-member allopathic medical schools.

Social reintegration of drug-addicted individuals living in therapeutic communities / Reinserção social de dependentes químicos residentes em comunidades terapêuticas / Reinserción social de dependientes químicos residentes en comunidades terapéuticas

The study aimed to characterize actions and activities aimed at social reintegration of drug-addicted living in therapeutic communities. Forty-three communities were evaluated in the state of Goiás, with the use of a semi-structured questionnaire. Data were analyzed using descriptive statistics and the results showed that these communities have resident preparation mechanisms for therapeutic discharge and referral to the labor market. However, few activities are developed for inclusion in the labor market. Family’s involvement in treatment of residents is stimulated with joint visits and activities. Although the relevant work of communities, help from public policies is needed for social assistance to contribute to the reintegration of these individuals in society.

O estudo teve por objetivo caracterizar as ações e atividades voltadas para a reinserção social de dependentes químicos residentes em comunidades terapêuticas. Foram avaliadas 43 comunidades, localizadas no estado de Goiás, com a utilização de um questionário semiestruturado. Os dados foram analisados por meio de estatística descritiva e os resultados apontaram que essas comunidades apresentam mecanismos de preparo do residente para a alta terapêutica e encaminhamento ao mercado de trabalho. Entretanto, desenvolvem poucas atividades para a inserção no mercado de trabalho. O envolvimento da família no tratamento dos residentes é estimulado com visitas e atividades conjuntas. Conclui-se que embora o trabalho das comunidades seja relevante, ainda carece de ajuda de políticas públicas de assistência social que contribuam com a reinserção desses indivíduos na sociedade.

El estudio tuvo por objetivo caracterizar las acciones y actividades vueltas para la reinserción social de dependientes químicos residentes en comunidades terapéuticas. Fueron evaluadas 43 comunidades, localizadas en el estado de Goiás, con la utilización de un cuestionario semiestructurado. Los datos fueron analizados por medio de estadística descriptiva y los resultados apuntaron que esas comunidades presentan mecanismos de preparo del residente para la alta terapéutica y encaminamiento al mercado de trabajo. Mientras, desarrollan pocas actividades para la inserción en el mercado de trabajo. El envolvimiento de la familia en el tratamiento de los residentes es estimulado con visitas y actividades conjuntas. Se concluye que aunque el trabajo de las comunidades sea relevante, aún carece de ayuda de políticas públicas de asistencia social que aporten con la reinserción de eses individuos en la sociedad.

Serviços de saúde e comunidades terapêuticas: há uma relação em prol do dependente químico? / Health services and therapeutic communities: is there a relationship for the drug-dependent patient?

O uso de droga é um dos principais problemas de saúde pública em todo o mundo. Para o auxílio no tratamento aos dependentes químicos existem no Brasil alguns serviços, dentre eles se encontram as comunidades terapêuticas que são instituições não governamentais que devem funcionar de forma articulada com a atenção básica de saúde e com os Centros de Atenção Psicossocial (CAPS). O objetivo deste estudo foi analisar o relacionamento entre as Comunidades Terapêuticas com os serviços de atenção à saúde. Foram pesquisadas 43 comunidades localizadas no município de Goiânia-GO, sua região metropolitana e também a cidade de Anápolis-GO. O trabalho de campo foi realizado por meio da aplicação do questionário. Todas as comunidades visitadas faziam uso do Sistema Único de Saúde (SUS) e, na contramão desse constante uso, identificou-se que não há uma relação efetiva entre as comunidades e os CAPS. As comunidades possuem o direito e o dever de proporcionar aos residentes o acesso ao SUS garantidos por lei. Já o CAPS como instituição de serviço voltado para o tratamento e reinserção social dos usuários de drogas serviria como um pilar, juntamente, com as comunidades no auxílio ao dependente químico. A relação entre os serviços de saúde e as comunidades pesquisadas se apresenta, em princípio, a favor dos dependentes químicos. No entanto, há a necessidade de haver uma maior interlocução entre os serviços de saúde, principalmente os CAPS e as comunidades visando a reabilitação integral dos residentes.

One of the main problems in public health is the use of illicit drugs. Several services are an aid in the treatment of illicit drugdependent people among which may be mentioned the therapeutic communities. They are non-governmental organizations which function together with the Basic Health Care and with Centers for Psychosocial Care (SAPS). Current analysis deals with the relationship between therapeutic communities and Health Services available at the National Health Service (SUS). Forty-three communities were researched in the municipality of Goiânia GO Brazil, the metropolitan region and the city of Anápolis GO Brazil. Field work was undertaken with a questionnaire. All communities visited use SUS services, but there is no relationship between the communities and CAPS. Communities have the right and the duty to provide resident people access to SUS, which is warranted by law. As a service institution for the treatment and social reinsertion of illicit drug users, CAPS is an important institution for communities in their aid for the drug user. The relationship between health service and communities is primarily for drug dependent people. However, greater interlocution must exist between the communities and CAPS for the integral rehabilitation of residents.

Neuromagnetic evidence for early auditory restoration of fundamental pitch.

BACKGROUND: Understanding the time course of how listeners reconstruct a missing fundamental component in an auditory stimulus remains elusive. We report MEG evidence that the missing fundamental component of a complex auditory stimulus is recovered in auditory cortex within 100 ms post stimulus onset. METHODOLOGY: Two outside tones of four-tone complex stimuli were held constant (1200 Hz and 2400 Hz), while two inside tones were systematically modulated (between 1300 Hz and 2300 Hz), such that the restored fundamental (also knows as "virtual pitch") changed from 100 Hz to 600 Hz. Constructing the auditory stimuli in this manner controls for a number of spectral properties known to modulate the neuromagnetic signal. The tone complex stimuli only diverged on the value of the missing fundamental component. PRINCIPAL FINDINGS: We compared the M100 latencies of these tone complexes to the M100 latencies elicited by their respective pure tone (spectral pitch) counterparts. The M100 latencies for the tone complexes matched their pure sinusoid counterparts, while also replicating the M100 temporal latency response curve found in previous studies. CONCLUSIONS: Our findings suggest that listeners are reconstructing the inferred pitch by roughly 100 ms after stimulus onset and are consistent with previous electrophysiological research suggesting that the inferential pitch is perceived in early auditory cortex.

Organizational models of educational technology in U.S. and Canadian medical schools.

PURPOSE: To examine the organizational structure of educational technology units within U.S. and Canadian medical schools in order to (1) identify organization models that support educational technology, (2) describe key attributes of these models, and (3) discuss the strengths and challenges associated with these models. METHOD: The authors distributed a survey to 88 schools that had previously provided information on their educational technology services and infrastructure. The authors developed the survey through a series of pilots and, then, from the data for each respondent school, created concept maps, which were used to identify organizational models. The authors conducted analyses to determine differences among models. The authors coded the comments about organizational models and identified themes. RESULTS: The authors received adequate data for analysis from 61 schools (69%). Four models for educational technology organizations emerged: (1) centralized units located in the school of medicine, (2) centralized units located at the health science center, (3) centralized units at the comprehensive university, and (4) no centralized unit (Dispersed Model). The majority (75%) of schools relied on some type of centralized organization. Whereas few organization attributes proved to be statistically significant, the centralized models have more resources devoted to educational technology and a closer alignment with the academic mission than the Dispersed Model. CONCLUSIONS: Medical schools primarily use central models. The authors recommend that schools structuring their educational technology resources consider exploration of a central model because of its focused use of resources to improve teaching and learning.