Bone mineral density around the knee after open wedge high tibial osteotomy measured up to 24 months in 51 patients.

PURPOSE: To evaluate bone mineral density (BMD) and radiographic and clinical outcomes of patients with varus knee osteoarthritis treated with open wedge high tibial osteotomy (OWHTO). We hypothesised that medial condyle BMD would decrease and lateral condyle BMD would increase after OWHTO. METHODS: Overall, 51 patients (mean age: 65.3 years; female: 40, male: 11) treated with OWHTO were prospectively enrolled. Several angles using whole single-leg radiographs were measured preoperatively and up to 24 months postoperatively. Five square tibial regions of interest (ROI) located below the proximal tibia as T1-T5 from medial to lateral regions and two square femoral ROI as F1 and F2 from medial and lateral regions, respectively, were defined. M/L BMD ratio was used to define the medial-to-lateral condyle BMD ratio. Femoral condyle BMD (F1 and F2) around the knee, as well as lumbar spine, and ipsilateral and contralateral femoral neck BMD, were measured before OWHTO and 3, 6, 12 and 24 months after OWHTO using dual-energy X-ray absorptiometry. Furthermore, tibial condyle BMD (T1-T5) around the knee was measured before and 24 months after OWHTO. Clinical outcomes were evaluated using the Knee Society knee and function scores, the Knee Injury and Osteoarthritis Outcome Score, and the Lysholm score preoperatively and 24 months postoperatively. A power analysis was performed. RESULTS: F1 BMD decreased by 19.2% from before to 3 months postoperatively. F2 BMD did not change up to 24 months after OWHTO. Femoral M/L BMD ratio decreased by 22.2% 3 months after OWHTO. T1 BMD and tibial M/L BMD ratio decreased, whilst T3, T4 and T5 BMD increased 24 months after OWHTO. Mean hip-knee-ankle angle (HKA) and weight-bearing line ratio were corrected from - 6.8° to 4.5° and 14.7 to 60.7%, respectively, postoperatively. Lumbar spine BMD did not change up to 12 months postoperatively. Ipsilateral femoral neck BMD decreased up to 6 months after OWHTO. CONCLUSION: Medial femoral condyle BMD decreased rapidly within 3 months and continued to decrease up to 12 months, but lateral femoral condyle BMD did not change after OWHTO. BMD measurements around the knee condyle enabled the evaluation of the changes in stress distribution before and after OWHTO with accelerated rehabilitation. LEVEL OF EVIDENCE: II.

Rotational Changes in the Distal Tibial Fragment Relative to the Proximal Tibial Fragment at the Osteotomy Site after Open-Wedge High-Tibial Osteotomy.

The present study is aimed at assessing the changes in tibial rotation at the osteotomy site after an open-wedge, high-tibial osteotomy (OWHTO) and analysing the factors that affect rotational changes in the distal tibial fragment relative to the proximal tibial fragment at the same site. This study involved 53 patients (60 knees; 16 males and 37 females) with medial osteoarthritis (OA) who underwent OWHTO and preoperative and 3-month postoperative computed tomography (CT) scans. Rotational angles of the distal tibia were measured using Stryker OrthoMap 3D by comparing preoperative and postoperative CTs. The mean rotational angle yielded an external rotation of 2.9° ± 4.8°. There were 17 knees with internal rotations, 37 knees with external rotations, and one knee with no rotation. The rotational angle significantly correlated with the resultant change in the femorotibial angle (correction angle) and the angle between the ascending and transverse osteotomy lines on the anterior osteotomised surface on which a flange was formed with the distal tibial osteotomised surface (flange angle). The flange angle affected the rotation, but it may have been affected by our surgical technique. The rotational angle did not significantly correlate with the change in the angle of the posterior tibial slope or body mass index. There were significant correlations between the rotational angle and correction angle (r = 0.42, p < 0.05). Additionally, the rotational angle correlated with the flange angle (r = -0.41, p < 0.05).

Executive dysfunction in medication-naïve children with ADHD: A multi-modal fNIRS and EEG study.

OBJECTIVE: Children with attention deficit hyperactivity disorder (ADHD) exhibit deficits in executive function. Since there are no clear biomarkers for the disorder, this study aimed to investigate the neurophysiological biomarkers for deficits in executive function in children with ADHD using functional near-infrared spectroscopy (fNIRS) and electroencephalography. METHODS: Twenty patients diagnosed with ADHD and 19 typically developing children (TDC; 8-11 years old) were included. Event related potentials (ERPs) were recorded using an electroencephalogram (EEG) and oxygenated hemoglobin concentrations (Oxy-Hb) were recorded using fNIRS during a colored Go/NoGo task, simultaneously. Latencies and amplitudes of NoGo-N2 and NoGo/Go-P3 tasks were measured using EEG. RESULTS: Children with ADHD showed significantly decreased Oxy-Hb in the right frontal cortex as well as longer NoGo-P3 latencies and a decreased NoGo/Go-P3 amplitude. There was a significant positive correlation between the Oxy-Hb and NoGo/Go-P3 amplitude. CONCLUSIONS: These results suggest that children with ADHD experience executive dysfunction. Hemodynamic and electrophysiological findings during the Go/NoGo task might be useful as a biomarker of executive function. SIGNIFICANCE: These findings have key implications for understanding the pathophysiology of deficits in executive function in ADHD.

Reduced Nogo-P3 in adults with developmental coordination disorder (DCD).

Nogo-N2 is associated with the premotor cognitive process that precedes motor response (e.g., conflict monitoring), whereas Nogo-P3 is related to the inhibition of the actual motor response. We examined the influence of motor clumsiness of developmental coordination disorder (DCD) on components of the event-related potential in a Go/Nogo task. Participants were healthy adults (N = 81) that were classified into control and DCD groups based on the Movement Assessment Battery for Children Second Edition. We manipulated the difficulty in stopping a response by varying the frequency of Nogo stimuli in a response task into rare (20%) and frequent (80%) conditions, and Nogo-N2 and Nogo-P3 were calculated from electroencephalograms (EEGs) during the Go/Nogo tasks. The commission error rate in the rare condition was significantly higher in the DCD group than in the control group, indicating that motor clumsiness decreases task performance. There were no differences in Nogo-N2 between DCD and control groups. However, Nogo-P3 in the rare condition was reduced in the DCD group compared to the control group. These results suggest that the influence of motor clumsiness is limited to the cognitive process after the initiation of the actual motor response.

Relationship between lower limb torsion and coronal morphologies of the femur and tibia in patients with medial knee osteoarthritis.

BACKGROUND: To investigate the relationship between femoral or tibial torsion and hip-knee-ankle angle (HKA), mechanical lateral distal femoral angle (mLDFA), or mechanical medial proximal tibial angle (mMPTA) in patients with medial knee osteoarthritis (OA). METHODS: A total of 75 knees were enrolled. Femoral and tibial torsions were measured by superimposing the axial planes of computed tomography images. The relationship between femoral or tibial torsion and HKA, mLDFA, or mMPTA on radiographs was examined. RESULTS: The mean femoral torsion was 12.2 ± 8.5° internally; femoral internal and external torsions were observed in 70 and 5 knees, respectively. The mean tibial external torsion was 18.0 ± 7.4° externally; tibial external torsion was observed in all 75 knees. Femoral internal and tibial external torsions increased with lower mMPTA (r = 0.33, P = 0.003; r = - 0.32, P = 0.005, respectively) but were not related to HKA or mLDFA. CONCLUSION: Femoral and tibial torsions were correlated with varus inclination of the proximal tibia in patients with medial knee OA.

Role of Inner Speech on Serial Recall in Children with ASD: A Pilot Study Using the Luria Hand Test.

This study was conducted to investigate the relation between the effect of articulatory suppression on the serial recall and severity of social impairments among children with autism spectrum disorders (ASD). The Luria hand test (LHT) was administered to evaluate the capacity for serial recall in 13 children with ASD. The LHT was administered under three conditions: control, under articulatory suppression, and under spatial suppression. Performance on the LHT of children with ASD was significantly lower in terms of both articulatory suppression and the spatial suppression condition. Moreover, the severity of social impairment in children with ASD was related to individual differences of effects of articulatory suppression on the LHT, but not with effects of spatial suppression. These results support the notion that dialogic inner speech which mediates complex cognitive abilities has inherently social origins.

Combined CT-based and image-free navigation systems in TKA reduces postoperative outliers of rotational alignment of the tibial component.

INTRODUCTION: Rotational malpositioning of the tibial component can lead to poor functional outcome in TKA. Although various surgical techniques have been proposed, precise rotational placement of the tibial component was difficult to accomplish even with the use of a navigation system. The purpose of this study is to assess whether combined CT-based and image-free navigation systems replicate accurately the rotational alignment of tibial component that was preoperatively planned on CT, compared with the conventional method. MATERIALS AND METHODS: We compared the number of outliers for rotational alignment of the tibial component using combined CT-based and image-free navigation systems (navigated group) with those of conventional method (conventional group). Seventy-two TKAs were performed between May 2012 and December 2014. In the navigated group, the anteroposterior axis was prepared using CT-based navigation system and the tibial component was positioned under control of the navigation. In the conventional group, the tibial component was placed with reference to the Akagi line that was determined visually. Fisher's exact probability test was performed to evaluate the results. RESULTS: There was a significant difference between the two groups with regard to the number of outliers: 3 outliers in the navigated group compared with 12 outliers in the conventional group (P < 0.01). CONCLUSIONS: We concluded that combined CT-based and image-free navigation systems decreased the number of rotational outliers of tibial component, and was helpful for the replication of the accurate rotational alignment of the tibial component that was preoperatively planned.

The use of factor Xa inhibitors following opening-wedge high tibial osteotomy for venous thromboembolism prophylaxis.

PURPOSE: This study aimed to investigate the incidence of venous thromboembolism (VTE) after medial opening-wedge high tibial osteotomy (OWHTO) and evaluate the efficacy and safety of edoxaban for the prevention of VTE in patients undergoing OWHTO. METHODS: A total of 139 patients with osteoarthritis or osteonecrosis undergoing OWHTO were enrolled in this prospective, randomized study. Four patients were excluded because of preoperatively diagnosed VTE, and 135 patients were divided into two groups-an edoxaban group and a non-edoxaban group-and underwent computed tomography venography on day 7 to check for postoperative VTE. Blood samples were taken on the day before OWHTO and on postoperative days 1, 3, 7, and 14. RESULTS: Treatment with edoxaban reduced the incidence of VTE after OWHTO; however, there was no statistically significant difference between the two groups. No major bleeding was noted in the edoxaban group. There were significant differences in the D-dimer level, prothrombin time, fibrinogen level, and thrombin antithrombin complex levels between the groups. CONCLUSIONS: Edoxaban is an oral, once-daily, selective, direct factor Xa inhibitor that is safe and easy to handle. It may offer a new option for preventing VTE after OWHTO. LEVEL OF EVIDENCE: I.