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Current techniques used for total knee arthroplasty rely on conventional instrumentation that violates the intramedullary canals. Accuracy of the instrumentation is questionable, and assembly and disposal of the numerous pieces is time consuming. Navigation techniques are more accurate, but their broad application is limited by cost and complexity. We aimed to prove a new concept of computer-assisted preoperative planning to provide patient-specific templates that can replace conventional instruments. Computed tomography-based planning was used to design two virtual templates. Using rapid prototyping technology, virtual templates were transferred into physical templates (cutting blocks) with surfaces that matched the distal femur and proximal tibia. We performed 45 total knee arthroplasties on 16 cadaveric and 29 plastic knees, including a comparative trial against conventional instrumentations. All operations were performed using patient-specific templates with no conventional instrumentations, intramedullary perforation, tracking, or registration. The mean time for bone cutting was 9 minutes with a surgical assistant and 11 minutes without an assistant. Computer-assisted analyses of six random computed tomography scans showed mean errors for alignment and bone resection within 1.7 degrees and 0.8 mm (maximum, 2.3 degrees and 1.2 mm, respectively). Patient-specific templates are a practical alternative to conventional instrumentations, but additional clinical validation is required before clinical use.

In recent years, parents in the United States and worldwide have purchased enormous numbers of videos and DVDs designed and marketed for infants, many assuming that their children would benefit from watching them. We examined how many new words 12- to 18-month-old children learned from viewing a popular DVD several times a week for 4 weeks at home. The most important result was that children who viewed the DVD did not learn any more words from their monthlong exposure to it than did a control group. The highest level of learning occurred in a no-video condition in which parents tried to teach their children the same target words during everyday activities. Another important result was that parents who liked the DVD tended to overestimate how much their children had learned from it. We conclude that infants learn relatively little from infant media and that their parents sometimes overestimate what they do learn.

Cognitive impairment affects more than half of all individuals living with multiple sclerosis (MS). We hypothesized that training at home with an adaptive online cognitive training program would have greater cognitive benefit than ordinary computer games in cognitively-impaired adults with MS. This was a double-blind, randomized, active-placebo-controlled trial. Participants with MS were recruited through Stony Brook Medicine and randomly assigned to either the adaptive cognitive remediation (ACR) program or active control of ordinary computer games for 60 hours over 12 weeks. Training was remotely-supervised and delivered through a study-provided laptop computer. A computer generated, blocked stratification table prepared by statistician provided the randomization schedule and condition was assigned by a study technician. The primary outcome, administered by study psychometrician, was measured by change in a neuropsychological composite measure from baseline to study end. An intent-to-treat analysis was employed and missing primary outcome values were imputed via Markov Chain Monte Carlo method. Participants in the ACR (n = 74) vs. active control (n = 61) training program had significantly greater improvement in the primary outcome of cognitive functioning (mean change in composite z score±SD: 0·25±0·45 vs. 0·09±0·37, p = 0·03, estimated difference = 0·16 with 95% CI: 0·02–0·30), despite greater training time in the active control condition (mean±SD:56·9 ± 34·6 vs. 37·7 ±23 ·8 hours played, p = 0·006). This study provides Class I evidence that adaptive, computer-based cognitive remediation accessed from home can improve cognitive functioning in MS. This telerehabilitation approach allowed for rapid recruitment and high compliance, and can be readily applied to other neurological conditions associated with cognitive dysfunction.Trial Registration: Clinicaltrials.gov NCT02141386

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Objective To explore the efficacy of remotely-supervised transcranial direct current stimulation (RS-tDCS) paired with cognitive training (CT) exercise in participants with multiple sclerosis (MS). Methods In a feasibility study of RS-tDCS in MS, participants completed ten sessions of tDCS paired with CT (1.5 mA × 20 min, dorsolateral prefrontal cortex montage). RS-tDCS participants were compared to a control group of adults with MS who underwent ten 20-min CT sessions through the same remotely supervised procedures. Cognitive outcomes were tested by composite scores measuring change in performance on standard tests (Brief International Cognitive Assessment in MS or BICAMS), basic attention (ANT-I Orienting and Attention Networks, Cogstate Detection), complex attention (ANT-I Executive Network, Cogstate Identification and One-Back), and intra-individual response variability (ANT-I and Cogstate identification; sensitive markers of disease status). Results After ten sessions, the tDCS group (n = 25) compared to the CT only group (n = 20) had significantly greater improvement in complex attention (p = 0.01) and response variability (p = 0.01) composites. The groups did not differ in measures of basic attention (p =0.95) or standard cognitive measures (p = 0.99). Conclusions These initial findings indicate benefit for RS-tDCS paired with CT in MS. Exploratory analyses indicate that the earliest tDCS cognitive benefit is seen in complex attention and response variability. Telerehabilitation using RS-tDCS combined with CT may lead to improved outcomes in MS.

Purpose: To devise a method for producing in vivo MRI images of the knee under physiologically significant loading, and to compare and evaluate the changes in cartilage characteristics before and during in situ compression of the knee. Material and Methods:A total of 26 asymptomatic subjects were imaged on a 1.5 Tesla Philips Intera scanner using a commercially available knee coil. Routine anatomical images were followed by T 2 map acquisition. These scans were repeated following in situ compression of the knee using a MR compatible loading jig.Results: Following loading to body weight, several regions of femoral cartilage show early alteration of T 2 relaxation time, most significantly in the medial and lateral peripheral zones. There were no significant changes in the tibial cartilage. Conclusions:The results establish the feasibility of measuring changes on MRI with in situ axial loading.

Animals are important stimuli for humans, and for children in particular. In three experiments, we explored children's affinity for animals. In Experiment 1, 11- to 40-month-old children were presented with a free-play session in which they were encouraged to interact with several interesting toys and two live animals - a fish and a hamster. Experiment 2 used the same methodology with 18- to 36-month-old children and two additional animals - a snake and a spider - to examine whether children's behaviours would differ for benign and potentially threatening animals. Finally, in Experiment 3, a more controlled paired-preference paradigm was employed to assess 18- to 33-month-old children's interactions with three live animals - a fish, hamster, and gecko - versus three physically similar toy animals. Across all three experiments, children interacted with the animals more often than with the toys. Further, they behaved differently towards the animals than the toys, talking about the animals more than the toys and asking more questions about them. The parents of the children also spent more time interacting with the animals, directing their children's attention more towards the animals than the toys. This research supports the idea that humans have an affinity for animals that draws their attention to animals, even when attractive toys are present.