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Abstract Background The variation of the anterolateral ligament (ALL) length during knee motion is still unclear, and the knee position in which a reconstruction graft should be tensioned remains controversial. The objective of this study was to determine the variation of the ALL length during knee motion using a three-dimensional optoelectronic system. Methods Kinematic analyses of 20 cadaveric knees were performed using a Motion Analysis® system. The variability of the measurements made during the five acquisition cycles was studied. Reliability was evaluated by two separate measurement sessions, with complete system reinstallation, using different cadavers and a new operator. The ALL length was analysed from extension to full flexion in three rotational conditions. Findings When analysing the reliability of the five cycles, 82% of the measurements we found to have an Intra Class Correlation (ICC) >0.85. The reproducibility of inter-sessional measures by different operators and different cadavers was either good (ICC >0.75) or excellent (ICC >0.85). The ALL length was maximum in full internal rotation with the knee at 25° of flexion. Interpretation This three-dimensional optoelectronic protocol allowed us to analyse the variation of the ALL length during intact knee motion with good reliability and the required accuracy to analyse this variable. The maximal length and highest tension of the ALL was reported at 25° of knee flexion in internal rotation, suggesting this as the optimal position for the knee joint when tensioning an ALL reconstruction. Highlights • Knee motion can be accurately assessed using 3D optoelectronic motion capture. • The protocol established is reliable, allowing accurate ALL length analysis. • The ALL length is maximum in full internal rotation with the knee in 25° of flexion. [ABSTRACT FROM AUTHOR]

Background and Purpose: Adolescent idiopathic scoliosis (AIS) is a structural, lateral curvature with rotation of the spine that develops around puberty. The influence of this spinal deformity on three-dimensional trunk movements during gait has not yet been elucidated. The aim of this study was to determine the influence of spinal curve pattern (single thoracic curve vs. single lumbar curve) on trunk kinematics during gait.Methods: Twenty-two patients with a single thoracic curve (Lenke type 1) and 17 patients with a single lumbar curve (Lenke type 5) were included in this study. Trunk symmetry in the sagittal, coronal, and transverse planes during gait was evaluated using an optoelectronic motion capture system.Results: In the type 1 group, the trunk was significantly rotated towards the concave side in the transverse plane during gait (mean difference of transverse rotation angle between concave side load and the convex side load, 8.8±0.6°, p<0.01). In the type 5 group, the trunk was significantly rotated towards the convex side in the coronal plane throughout the stance phase of gait (mean difference of coronal inclination angle, 1.9±0.3°, p<0.05).Conclusions: The AIS patients with a single thoracic curve showed asymmetrical trunk movement in the transverse plane, and patients with a single lumbar curve showed asymmetrical trunk movement in the coronal plane. These results indicate that the spinal curve pattern influenced trunk kinematics, and suggest that the global postural control strategy of patients with AIS differs according to the curve pattern. [ABSTRACT FROM AUTHOR]

When optoelectronic systems (OES) are used for control purposes in mechanical engineering, there is a risk of objective cracking caused by collision with hard particles of the environment. The article shows that it is possible to reduce the objective lens diameter two times without loss of resolution, and thus to improve impact resistance by reducing the probability of collision and objective lens cracking. [ABSTRACT FROM AUTHOR]

Objective To evaluate morphological differences of the facial soft tissue surface between male Japanese adults and children. Design 20 adult Japanese males (average age 28 years) and 20 Japanese boys (average age 5.5 years) with normal occlusion were selected for this study. The images of the subjects’ facial surface were obtained with a 3-D laser scanner. To evaluate the three-dimensional morphological differences of the facial soft tissue, we transformed the coordinates of 16 facial landmarks to a new reference plane and compared the adults’ and children's facial form drawn to the same scale in the same coordinate system. Results The morphological difference ratio of the lower facial area was higher than in the upper facial area, and the nose and lower face changed more forward than downward. The morphological difference ratio of the mid face width was smaller than other areas. Conclusion Our study suggests that the morphological facial soft tissue differences between Japanese adults and children are more forward and downward than laterally, manifesting in a facial form of adults that is deeper and narrow. [ABSTRACT FROM AUTHOR]

• The characteristics of original multi-channel image analysis measuring system for liquid film thickness changes with annular two-phase gas-very viscous liquid downward flow in vertical pipes has been presented. • The methodology of conducting study with the tests and analysis results of selected air-oil two-phase flow values has been presented. • The apparatus system introduced in the paper, is believed to be the most effective in terms of investigating the characteristics of oil liquid films and other dielectric liquids with a significant level of absorbing monochromatic radiation. • The measuring system introduced in the paper is believed to be very useful for industry. This paper presents the capabilities of an optoelectronic system to measure values describing the hydrodynamics of a two-phase downward flow in vertical pipes of a highly viscous liquid and gas. Common image processing methods used in the literature are unsuitable for the analysis of two-phase flow with particularly complex flow patterns. The designed and constructed measuring system and the appropriate selection of working media allowed measurements of a number of quantities characteristic for the gas–liquid flow falling in vertical pipes. The methodology of conducting measurements and their results as well as the analyses of selected quantities characterizing the two-phase flow are presented. The nature and form of the occurring waves are characterized. Experimental data are more accurate than those obtained with methods described in the literature. A camera placed in the flow channel limits the measurement to vertical downward flow only. [ABSTRACT FROM AUTHOR]

Abstract: Clinical practice for the evaluation of motor and cognitive capabilities often relies upon writing and drawing tests. A non-invasive method to capture handwriting and analyze data is therefore needed. In this work a method to capture motion of a pen through a mo-cap optoelectronic system was developed, which could solve the limits of systems based on graphic tablets. Four IR passive markers were placed on a pen cap. Once a pen was equipped with the cap, track of tip was computed through a numeric algorithm using the 3D coordinates of markers provided by the optoelectronic system. Some tests were performed to estimate the error in track reconstruction and to compare the new protocol with previous reconstruction methods. The results showed a higher accuracy of the new method. The new protocol also overcomes the problems related to pen grasping and marker covering that affected other methods described in the literature and permits the evaluation of writing and drawing kinematics as well as postural behaviour related to them. [Copyright &y& Elsevier]

Abstract: Background: Obesity is frequently associated with various musculoskeletal disorders including chronic low back pain (cLBP). Osteopathy is a discipline emphasizing the conservative treatment of the disease in an olistic vision. We designed a randomized controlled study to investigate whether Osteopathic Manipulative Treatment (OMT) combined with specific exercises (SE) is more effective than SE alone in obese patients with cLBP. Methods: nineteen obese females with cLBP, randomized into 2 groups: SE + OMT and SE were studied during the forward flexion of the spine using an optoelectronic system. A biomechanical model was developed in order to analyse kinematics and define angles of clinical interest. Outcome measures: kinematic of the thoracic and lumbar spine and pelvis during forward flexion, pain according to a visual analogue scale (VAS), Roland Morris Disability Questionnaire and Oswestry Low Back Pain Disability Questionnaire. Results: significant effects on kinematics were reported only for OMT + SE with an improvement in thoracic range of motion of nearly 20%. All scores of the clinical scales used improved significantly. The greatest improvements occurred in the OMT + SE group. Conclusions: combined rehabilitation treatment including Osteopathic Manipulative Treatment (OMT + SE) showed to be effective in improving biomechanical parameters of the thoracic spine in obese patients with cLBP. Such results are to be attributed to OMT, since they were not evident in the SE group. We also observed a reduction of disability and pain. The clinical results should be considered preliminary due to the small sample size. [Copyright &y& Elsevier]

Abstract: A new method for a quantitative and objective description of drawing and for the quantification of drawing ability in children with learning disabilities (LD) is hereby presented. Twenty-four normally developing children (N) (age 10.6±0.5) and 18 children with learning disabilities (LD) (age 10.3±2.4) took part to the study. The drawing tasks were chosen among those already used in clinical daily experience (Denver Developmental Screening Test). Some parameters were defined in order to quantitatively describe the features of the children''s drawings, introducing new objective measurements beside the subjective standard clinical evaluation. The experimental set-up revealed to be valid for clinical application with LD children. The parameters highlighted the presence of differences in the drawing features of N and LD children. This paper suggests the applicability of this protocol to other fields of motor and cognitive valuation, as well as the possibility to study the upper limbs position and muscle activation during drawing. [Copyright &y& Elsevier]

Objective. Main purpose of this study was to develop a biomechanical model for the analysis of sit-to-stand movement in normal and obese subjects.Design. A biomechanical model describing sit-to-stand was developed using kinetic and kinematic experimental data. Trunk flexion, feet movement, knee and hip joint torques were assumed as sensible indexes to discriminate between normal and obese subjects.Background. Sit-to-stand is a functional task that may become difficult for certain patients. The analysis of its execution provides useful biomechanical information on the motor ability of selected subjects.Methods. Sit-to-stand was recorded using an optoelectronic system and a force platform in 40 obese patients and 10 normal subjects. A biomechanical model was developed using inverse dynamics equations.Results. Kinematic and kinetic indexes evidenced differences in motion strategy between normal and obese subjects. Obese subjects rise from the chair limiting trunk flexion (mean value: 73.1°) and moving their feet backwards from initial position (mean deviation: 50 mm). Normal subjects, instead, show a higher trunk flexion (mean value: 49.2°, a lower angular value between trunk and the horizontal means increased flexion) and fixed feet position (mean deviation: 5 mm). As for kinetics, obese patients show knee joint torque higher than hip torque (maximum knee torque: 0.75 Nm/kg; maximum hip torque: 0.59 Nm/kg), while normal subjects show opposite behaviour (maximum knee torque: 0.38 Nm/kg; maximum hip torque: 0.98 Nm/kg).RelevanceWe found differences in motion strategy between normal and obese subjects performing sit-to-stand movement, which may be used to plan and evaluate rehabilitative treatments. [Copyright &y& Elsevier]

Through optoelectronic systems it's possible to have an objective dynamic analysis of the spine during movement suitable for everyday clinical practice. The aim of this study was to explore the forward bending (FB), lateral bending (LB) and axial rotation (AR) of the spine using a complete protocol focused only on the spine, in order to create a significant database of pattern of movements on healthy subjects. The research was conducted on a sample of 37. All the FB graphs are symmetrical and have fluid curves. Increased ROM during the functional tests was observed. It is highlighted the motor's learning and muscular fatigue phenomenon, through the analysis of the anticipatory postural adjustments (APAs). The series of graphs of LB and AR show asymmetry between the right and left movements, in which there is a dominant side. Through the results of this study, we can trace a motion profile of each single subject, and group the strategies adopted by participants to carry out the required movements. [ABSTRACT FROM AUTHOR]

Quantitative and qualitative measures of human movement can be two important features for clinical decision making. The purpose of this study is to evaluate the Intra-and inter- operator reliability of a novel hand protocol during grip movement. The experimental protocol required the positioning of 8 optoelectronic cameras and 24 markers. 5 healthy subjects have been recruited. Each subject received 2 markerizations by two different operators (A and B) and they carried out 3 tests at a time T0 and at a time T1 (a week after) for each markerization. Results have shown that Test-retest reliability of the markers positions measurements was good (test: 0,893, p < 0.001; retest: 0,773, p < 0.01) and intra-operator reliability was excellent (A: 0.983, p < 0.001; B: 0.993 p < 0.001). Overall, these results suggest that this protocol is reliable in order to develop future studies for its application in clinical practice. [ABSTRACT FROM AUTHOR]