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Abstract Functional assessment is a key element in evaluating adult spinal deformity (ASD) patients. The multitude of 3D kinematic parameters provided by movement analysis can be confusing for spine surgeons. The aim was to investigate movement patterns of ASD based on key kinematic parameters. 115 primary ASD and 36 controls underwent biplanar radiographs and 3D movement analysis during walking, sit-to-stand and stair ascent to calculate joint and segment kinematics. Principal component analysis was applied to identify the most relevant kinematic parameters that define movement strategies adopted by ASD. Pelvis and head relative to pelvis kinematics were the most relevant parameters. ASD patients adopted four different movement strategies. Class 1: normative head and pelvis kinematics. Class 2: persistent pelvic backward tilt. Class 3: persistent forward shift of the head. Class 4: both pelvic backward tilt and forward shift of the head. Patients in class 3 and 4 presented sagittal malalignment on static radiographs with increased pelvic tilt, pelvic incidence-lumbar lordosis mismatch and sagittal vertical axis. Surprisingly, patients in class 3 had normal pelvic kinematics during movement, showing the importance of functional evaluation. In addition to being key segments in maintaining static global posture, head and pelvis were found to define movement patterns.

Introduction: Radiographic analysis is necessary for the assessment and the surgical planning in adults with spinal deformity (ASD). Restoration of global alignment is key to improving patient's quality of life. However, the large number of existing global alignment parameters can be confusing for surgeons. Research question: To determine the most clinically and functionally relevant global alignment parameters in ASD. Material and methods: ASD and controls underwent full body biplanar X-ray to calculate global alignment parameters: odontoid to hip axis angle (OD-HA), global sagittal angle (GSA), global tilt (GT), SVA, center of auditory meatus to hip axis (CAM-HA), SSA, T1-tilt and T9-tilt. All subjects filled HRQoL questionnaires: ODI, SF-36, VAS for pain and BDI (Beck's Depression Inventory). 3D gait analysis was performed to calculate kinematic and spatio-temporal parameters. A machine learning model predicted gait parameters and HRQoL scores from global alignment parameters. Results: 124 primary ASD and 47 controls were enrolled. T9 tilt predicted the most BDI (31%), hip flexion/extension during gait (36%), and double support time (39%). GSA predicted the most ODI (26%), thorax flexion/extension during gait (33%), and cadence (36%). Discussion and conclusion: Among all global alignment parameters, GSA, evaluating both trunk shift and knee flexion, and T9 tilt, evaluating the shift of the center of mass, were the best predictors for most of HRQoL scores and gait kinematics. Therefore, we recommend using GSA and T9 tilt in clinical practice when evaluating ASD because they represent the most quality of life and functional kinematic of these patients.

IntroductionAdult spinal deformity (ASD) is classically evaluated by health-related quality of life (HRQoL) questionnaires and static radiographic spino-pelvic and global alignment parameters. Recently, 3D movement analysis (3DMA) was used for functional assessment of ASD to objectively quantify patient's independence during daily life activities. The aim of this study was to determine the role of both static and functional assessments in the prediction of HRQoL outcomes using machine learning methods.MethodsASD patients and controls underwent full-body biplanar low-dose x-rays with 3D reconstruction of skeletal segment as well as 3DMA of gait and filled HRQoL questionnaires: SF-36 physical and mental components (PCS&MCS), Oswestry Disability Index (ODI), Beck's Depression Inventory (BDI), and visual analog scale (VAS) for pain. A random forest machine learning (ML) model was used to predict HRQoL outcomes based on three simulations: (1) radiographic, (2) kinematic, (3) both radiographic and kinematic parameters. Accuracy of prediction and RMSE of the model were evaluated using 10-fold cross validation in each simulation and compared between simulations. The model was also used to investigate the possibility of predicting HRQoL outcomes in ASD after treatment.ResultsIn total, 173 primary ASD and 57 controls were enrolled; 30 ASD were followed-up after surgical or medical treatment. The first ML simulation had a median accuracy of 83.4%. The second simulation had a median accuracy of 84.7%. The third simulation had a median accuracy of 87%. Simulations 2 and 3 had comparable accuracies of prediction for all HRQoL outcomes and higher predictions compared to Simulation 1 (i.e., accuracy for PCS = 85 ± 5 vs. 88.4 ± 4 and 89.7% ± 4%, for MCS = 83.7 ± 8.3 vs. 86.3 ± 5.6 and 87.7% ± 6.8% for simulations 1, 2 and 3 resp., p

Abstract The bilateral sagittal split osteotomy is considered the standard surgery to correct facial asymmetries. More recently, unilateral sagittal split osteotomy (USSO) was used to treat such malocclusions. Aim To assess facial symmetry following USSO in the treatment of class III laterognathia. Methods Frontal facial photographs of four groups of patients were assessed: (1) pre-surgical group (n = 30) with skeletal asymmetry, (2) postsurgical group assessing patients of the first group 2 years after USSO, (3) control group (n = 30) of patients judged to have harmonious facial norms, and (4) mirrored group (n = 30) in which the control photographs were altered by duplicating the right half side of the face to replace the left half, thus creating perfectly symmetrical faces. All 120 photographs were distributed to 40 expert orthodontists to evaluate and score facial symmetry using the visual analog scale. Skin sensitivity and temporomandibular joint (TMJ) disorders were also assessed clinically pre and postsurgically. Results Statistically significant differences were observed between the pre-surgical group and each of the postsurgical and control groups (p < 0.001). The control and postsurgical groups received similar scores of symmetry (p = 0.774). The mirrored group received statistically significantly higher symmetry scores than either of the control or the postsurgical groups (p < 0.001). A reduction in TMJ disorders was noted after USSO and all patients reported normal skin sensation 2 years post-surgery. Conclusion When indicated, USSO is a dependable and practical surgical approach to correct facial asymmetries associated with class III malocclusion.

In this study, the authors monitor a hydrothermal fluid surge through seismic anisotropy changes at the Hakone volcanic field, Japan. The authors find the anisotropy changes to be set off by the seismic waves of the 2011 Tohoku-Oki earthquake, that reactivated the hydrothermal system.

Abstract Background To evaluate the success rate of orthodontic mini-implant (MI) in relation to implant characteristics, mainly implant distance to alveolar crestal bone (AC) and root proximity (RP) to adjacent teeth. Methods Two hundred sixty MIs (209 in maxilla, 51 in mandible) were categorized into success (n = 229) and failure (n = 31) groups. Distances from MI to the most adjacent tooth (DT) and to AC level (DC) were measured on periapical radiographs taken with the orthoradial projection technique. Appropriate statistical tests (chi-square, t test, logistic regression) were applied. Results DC measurements were statistically significantly greater in the success group (7.46 ± 1.7 mm) compared to 3.43 ± 0.81 mm in the failure group. Root proximity was not associated with miniscrew failure. Patient age, mini-implant site, and DC were significant predictors of mini-implant failure (p

Facial flatness indices have been used in anthropology to discern differences among populations. They were evaluated on skulls from around the world. Aims (1) to evaluate the use of facial flatness indices in orthodontics and (2) to assess their variation among malocclusions, age and sex. Materials and Methods A total of 322 cone beam computed tomography radiographs were digitized and three facial indices (frontal, simotic and zygomaxillary) along with three transverse distances (fmo1–fmo2, zma1–zma2 and n1–n2) were assessed and compared between different groups. Results The zygomaxillary index was increased in Class II (32.6 ± 0.42; p < 0.001) and decreased in Class III malocclusions (29.4 ± 0.66; p < 0.001) compared to Class I (31.18 ± 0.3; p < 0.001). The frontal and nasal flatness are not characteristic features of any of the sagittal malocclusions. Facial flatness indices did not differ between males and females and between growing and non-growing patients. Conclusion The position of subspinale point (A point) forward or backward relative to the zygomaxillary width is a factor of assessment of facial flatness. The zygomaxillary index could be helpful in weighting proportionally the width of the maxilla (expansion) relative to its sagittal position in Class II and Class III malocclusions.

Background and Objective. In forensic investigations, mandibular canines provide excellent materials to identify gender since they are more likely to survive disasters. The objective of this study was to investigate gender dimorphism by comparing the mesiodistal width of mandibular permanent canines and intercanine distance in a group of Lebanese population. Methods. Participants consisted of undergraduate students from the School of Dentistry, Lebanese University, for two academic years who fulfilled the inclusion criteria. Canine widths and intercanine distance were measured by one operator directly on dental casts using a digital caliper. Results. One hundred thirty-three Lebanese dental students (54 males and 69 females) aged 18–25 were included in the study. The intercanine distance was significantly greater in males (P value < 0.0001). The right and the left canine widths were significantly greater in males than in females (P value < 0.0001). However, no significant difference was found between left and right canines for males (P value > 0.05) and females (P value > 0.05). The mean width of canine was greater than 7.188 mm for males. Conclusion. The parameters measured in the present study are of great help in sex identification in forensic investigations in the Lebanese adult population.