Parkinson's disease classification with CWNN: Using wavelet transformations and IMU data fusion for improved accuracy.

BACKGROUND: Parkinson's disease (PD) is a chronic neurodegenerative disorder characterized by motor impairments and various other symptoms. Early and accurate classification of PD patients is crucial for timely intervention and personalized treatment. Inertial measurement units (IMUs) have emerged as a promising tool for gathering movement data and aiding in PD classification. OBJECTIVE: This paper proposes a Convolutional Wavelet Neural Network (CWNN) approach for PD classification using IMU data. CWNNs have emerged as effective models for sensor data classification. The objective is to determine the optimal combination of wavelet transform and IMU data type that yields the highest classification accuracy for PD. METHODS: The proposed CWNN architecture integrates convolutional neural networks and wavelet neural networks to capture spatial and temporal dependencies in IMU data. Different wavelet functions, such as Morlet, Mexican Hat, and Gaussian, are employed in the continuous wavelet transform (CWT) step. The CWNN is trained and evaluated using various combinations of accelerometer data, gyroscope data, and fusion data. RESULTS: Extensive experiments are conducted using a comprehensive dataset of IMU data collected from individuals with and without PD. The performance of the proposed CWNN is evaluated in terms of classification accuracy, precision, recall, and F1-score. The results demonstrate the impact of different wavelet functions and IMU data types on PD classification performance, revealing that the combination of Morlet wavelet function and IMU data fusion achieves the highest accuracy. CONCLUSION: The findings highlight the significance of combining CWT with IMU data fusion for PD classification using CWNNs. The integration of CWT-based feature extraction and the fusion of IMU data from multiple sensors enhance the representation of PD-related patterns, leading to improved classification accuracy. This research provides valuable insights into the potential of CWT and IMU data fusion for advancing PD classification models, enabling more accurate and reliable diagnosis.

Impact of temperature changes to the adhesion strength of molar tubes: an in vitro study.

BACKGROUND: The main purpose of this was to determine study adhesion strength of molar tubes bonding with a composite adhesive after exposure to a sudden change in temperature (thermal cycles). METHODS: The study sample consisted of 40 recently extracted human first permanent molars, which were randomly divided into two groups of 20: group 1 was the experimental group (affected by thermal cycles), and group 2 was the control group. Molar tubes were bonded with a light-cure tube adhesive. The experimental group teeth were dipped 2,000 times in saline at 5 °C and at 55 °C. The control group were immersed in 37 °C saline. Molar tubes for both groups were removed with an adapted Mecmesim Multitesters 2.5-I, and the data were recorded with EMPEROR software. ANOVA was used to calculate and compare the results. RESULTS: In the experimental group of the teeth, the maximum force was obtained at 94.2 N and the lowest force was 19.69 N. In the control group of the teeth, the maximum force was obtained at 159.1 N and the lowest force was 28.1 N. In the experimental group, the mean debonding force (59.12 N) was statically significantly smaller than in the control group (79.88 N), p = 0.0345. The forces in the control group were by 1.35 times greater than those in the experimental group. CONCLUSIONS: The forces of the adhesion of molar tubes to the tooth surface were reduced after exposure to a sudden change in temperature (thermal cycles). The results were significantly different between the experimental group and the control group.

Application of nonlinear analysis for the assessment of gait in patients with Parkinson's disease.

BACKGROUND: Gait can be affected by diseases such as Parkinson's disease (PD), which lead to alterations like shuffle gait or loss of balance. PD diagnosis is based on subjective measures to generate a score using the Unified Parkinson's Disease Rating Scale (UPDRS). To improve clinical assessment accuracy, gait analysis can utilise linear and nonlinear methods. A nonlinear method called the Lyapunov exponent (LE) is being used to identify chaos in dynamic systems. This article presents an application of LE for diagnosing PD. OBJECTIVE: The objectives were to use the largest Lyapunov exponents (LaLyEx), sample entropy (SampEn) and root mean square (RMS) to assess the gait of subjects diagnosed with PD; to verify the applicability of these parameters to distinguish between people with PD and healthy controls (CO); and to differentiate subjects within the PD group according to the UPDRS assessment. METHODS: The subjects were divided into the CO group (n= 12) and the PD group (n= 14). The PD group was also divided according to the UPDRS score: UPDRS 0 (n= 7) and UPDRS 1 (n= 7). Kinematic data of lower limbs were measured using inertial measurement units (IMU) and nonlinear parameters (LaLyEx, SampEn and RMS) were calculated. RESULTS: There were significant differences between the CO and PD groups for RMS, SampEn and the LaLyEx. After dividing the PD group according to the UPDRS score, there were significant differences in LaLyEx and RMS. CONCLUSIONS: The selected parameters can be used to distinguish people with PD from CO subjects, and separate people with PD according to the UPDRS score.

Analysis of Functional Recovery and Subjective Well-Being after Arthroscopic Rotator Cuff Repair.

Background: Rotator cuff tears are common causes of functional shoulder instability and often lead to arthroscopic rotator cuff repair. A well-programmed rehabilitation leads to successful tendon healing, positive functional recovery and subjective well-being (SWB). Objective: To evaluate the changes in shoulder functioning and SWB pre-, post-outpatient rehabilitation and after one-month follow-up. Materials and Methods: A total of 44 patients were assessed three times: at the beginning (six weeks' post-surgery), at the end of outpatient rehabilitation (2-3 weeks) and one month after rehabilitation. The outcome measures were the Disabilities of the Arm, Shoulder and Hand score (DASH), active range of motion (ROM), manual muscle testing (MMT), hand dynamometry (HD) and pain level by a Visual Analogue Scale (VAS). SWB was assessed by Rosenberg self-esteem scale (RSES), Positive and Negative Affect Schedule (PANAS) and the Lithuanian Psychological Well-Being Scale (LPWBS). Results are presented as a difference between periods. Results: Affected shoulder motor function (MMT, HD and ROM) significantly improved in three periods (p < 0.05); however, major recovery was observed in the follow-up period. VAS scores meaningfully decreased over all stages and negatively correlated with motor function recovery (p < 0.05). DASH rates exhibited significant retrieval in all phases, especially in follow-up. SWB results demonstrated the larger effects of self-evaluation in follow-up, improved daily functions and psychological wellness, then negative emotions significantly decreased (p < 0.05). Conclusions: The experienced pain and psychosocial factors significantly influence functional recovery of the shoulder during rehabilitation. The improvement in motor function, ability and pain relief during rehabilitation increases level of SWB, psychological wellness and positive emotional affect in long-term context.

Quantitative body symmetry assessment during neurological examination.

BACKGROUND: A lack of movement coordination characterized by the undershoot or overshoot of the intended location with the hand, arm, or leg is often found in individuals with multiple sclerosis (MS). Standardized as Finger-to-Nose (FNT) and The Heel-to-Shin (HST) tests are the most frequently used tests for qualitative examination of upper and lower body coordination. Inertial sensors facilitate in performing quantitative motion analysis and by estimating body symmetry more accurately assess coordination lesion and imbalance. OBJECTIVES: To assess the body symmetry of upper and lower limbs quantitatively, and to find the best body symmetry indices to discriminate MS from healthy individuals (CO). METHODS: 28 MS patients and 23 CO participated in the study. Spatiotemporal parameters obtained from six Inertial Measurement Units (IMUs) were placed on the upper and lower extremities during FNT and HST tests. All data were analyzed using statistical methods in MATLAB. RESULTS: Asymmetry indices of temporal parameters showed a significant increase in upper body and lower body asymmetry of MS compared to CO. However, CO have a greater kinematic asymmetry compared to MS. CONCLUSION: Temporal parameters are the most sensitive to body asymmetry evaluation. However, range of motion is completely inappropriate if it is calculated for one movement cycle.

Quantitative Analysis of Parkinsonian Tremor in a Clinical Setting Using Inertial Measurement Units.

BACKGROUND: Parkinson's disease (PD) is a neurodegenerative disorder that affects human voluntary movements. Tremor is one of the most common symptoms of PD and is expressed as involuntary oscillation of the body. Tremors can be analysed in the frequency domain. OBJECTIVE: The aim of the current study was to examine selected tremor parameters (frequency, root mean square, and approximated entropy) in order to quantify the characteristics of patients diagnosed with PD, compared to a healthy control group, and to compare the parameters by dividing the subjects according to UPDRS assessment. METHODS: The subjects were divided into two groups: a group of people diagnosed with PD (n = 19) and a control group consisting of healthy volunteers (CO = 12). Each subject performed motor tasks specific to certain tremors: the finger-to-nose test. Each subject performed a motor task three times. A nine degree of freedom (DOF) wireless inertial measurement unit was used for the measurement of upper limb motor tasks. For the quantitative estimation of kinetic and postural tremors, dominant frequency, root means square, and approximation entropy were selected and calculated from the measured angular velocity and linear acceleration signals. A one-way ANOVA with a significance level of α = 0.05 was used to test the null hypothesis that the means of the tremor metrics were the same between the PD and CO groups. RESULTS: Statistically significant differences between PD patients and control groups were observed in ApEn acceleration signal of kinetic tremor, ApEn angular velocity signal of kinetic tremor, ApEn angular velocity of postural tremor, frequency acceleration signal of postural tremor, and RMS angular speed kinetic tremor. CONCLUSION: Application of inertial measurement units for clinical research of patients and PD tremor evaluation allows providing quantitative information for diagnostic purposes, during screening in a clinical setting that differentiates between PD patients and controls.

Effects of robot-assisted training on upper limb functional recovery during the rehabilitation of poststroke patients.

BACKGROUND: The study aims to determine the effectiveness of robot-assisted training in the recovery of stroke-affected arms using an exoskeleton robot Armeo Spring. OBJECTIVE: To identify the effect of robot training on functional recovery of the arm. METHODS: A total of 34 stroke patients were divided into either an experimental group (EG; n= 17) or a control group (n= 17). EG was also trained to use the Armeo Spring during occupational therapy. Both groups were clinically assessed before and after treatment. Statistical comparison methods (i.e. one-tailed t-tests for differences between two independent means and the simplest test) were conducted to compare motor recovery using robot-assisted training or conventional therapy. RESULTS: Patients assigned to the EG showed a statistically significant improvement in upper extremity motor function when compared to the CG by FIM (P< 0.05) and ACER (P< 0.05). The calculated treatment effect in the EG and CG was meaningful for shoulder and elbow kinematic parameters. CONCLUSIONS: The findings show the benefits of robot therapy in two areas of functional recovery. Task-oriented robotic training in rehabilitation setting facilitates recovery not only of the motor function of the paretic arm but also of the cognitive abilities in stroke patients.

Necessity of early-stage verticalization in patients with brain and spinal cord injuries: Preliminary study.

BACKGROUND: Integration of the verticalization robot, Erigo, with functional electric stimulation and passive leg movements in the postacute rehabilitation of neurological patients could reduce the risk of secondary complications and improve functional outcomes (i.e. orthostatic hypotension, postural control and walking ability). OBJECTIVE: The aim of this study was to estimate and quantify changes in the postacute stage, mainly related to heart rate and blood pressure in functional recovery, postural parameters, walking ability and psychoemotional reactions, during training using the verticalization robot Erigo. METHODS: Six patients [three suffering from a stroke (ST) and three with spinal cord injuries (SCI)] participated in 10 sessions of physical therapy with the verticalization robot during primary inpatient rehabilitation. Functional state changes were assessed using clinical tests before and after the treatment, and the loading tolerance during Erigo training was noted. RESULTS: In early rehabilitation, Erigo training was safe and effective at improving orthostatic tolerance, posture and positive emotional reactions in both the ST and SCI patients (P< 0.05). In addition, advanced technologies were more effective at boosting the orthostatic tolerance in SCI patients, while they were more effective at increasing the dynamic balance and walking ability in ST patients (P< 0.05).

Quantitative assessment of upper extremities motor function in multiple sclerosis.

BACKGROUND: Upper extremity (UE) motor function deficits are commonly noted in multiple sclerosis (MS) patients and assessing it is challenging because of the lack of consensus regarding its definition. Instrumented biomechanical analysis of upper extremity movements can quantify coordination with different spatiotemporal measures and facilitate disability rating in MS patients. OBJECTIVE: To identify objective quantitative parameters for more accurate evaluation of UE disability and relate it to existing clinical scores. METHODS: Thirty-four MS patients and 24 healthy controls (CG) performed a finger-to-nose test as fast as possible and, in addition, clinical evaluation kinematic parameters of UE were measured by using inertial sensors. RESULTS: Generally, a higher disability score was associated with an increase of several temporal parameters, like slower task performance. The time taken to touch their nose was longer when the task was fulfilled with eyes closed. Time to peak angular velocity significantly changed in MS patients (EDSS > 5.0). The inter-joint coordination significantly decreases in MS patients (EDSS 3.0-5.5). Spatial parameters indicated that maximal ROM changes were in elbow flexion. CONCLUSIONS: Our findings have revealed that spatiotemporal parameters are related to the UE motor function and MS disability level. Moreover, they facilitate clinical rating by supporting clinical decisions with quantitative data.

Intrapersonal and interpersonal evaluation of upper extremity kinematics.

BACKGROUND: The quality of upper extremity (UE) function can be evaluated by measuring the kinematic parameters of patient movements. OBJECTIVE: This investigation focused on finding the angles and angular velocity amplitudes of UE motions in healthy participants to compare with the experimental results of patients with a UE disability who are trying to recover previous movement conditions. METHODS: The UE motions of 23 healthy adult volunteers were tested using a three-dimensional motion capture system and measuring hand segment motions. A simplified 7 degrees of freedom (DOF) human arm kinematic model created within MATLAB and used to process the experimental data. RESULTS: The interpersonal CV (coefficients of variability) of left-side motions showed that the lowest CV of linear velocity amplitudes was at elbow flexion (4.2%), but the highest was at wrist extension (48.3%). The lowest and highest CV of angular velocity amplitudes were 19.6% and 55.7%, during shoulder adduction and wrist extension, respectively. CONCLUSIONS: High interpersonal CV may restrict the direct comparison of kinematic parameters of UE in different healthy and disabled persons.

Biomechanical evaluation of native acromioclavicular joint ligaments and two reconstruction techniques in the presence of the sternoclavicular joint: A cadaver study.

BACKGROUND: Where is over 100 reconstruction techniques described for acromioclavicular (AC) joint reconstruction. Although, it is not clear whether the presence of the sternoclavicular (SC) joint influences the biomechanical properties of native AC ligaments and reconstruction techniques. The purpose of the present study was to investigate the biomechanical properties of native AC joint ligaments and two reconstruction techniques in cadavers with the SC joint still present. MATERIALS AND METHODS: We tested eight fresh-frozen cadaver hemithoraces for superior translation (70 N load) and translation increment after 1000 cycles (loading from 20 to 70 N) in a controlled laboratory study. There were three testing groups created: native ligaments, the single coracoclavicular loop (SCL) technique, and the two coracoclavicular loops (TCL) technique. Superior translation was measured after static loading. Translation increment was calculated as the difference between superior translation after cyclic and static loading. RESULTS: Native AC ligaments showed significantly lower translation than the SCL ( p = 0.023) and TCL ( p = 0.046) groups. The SCL had a significantly lower translation increment than native AC ligaments ( p = 0.028). There was no significant difference between reconstruction techniques in terms of translation ( p = 0.865) and translation increment ( p = 0.113). CONCLUSIONS: Native AC joint ligaments had better static properties than both reconstruction techniques and worse dynamic biomechanical properties than the SCL technique. The SCL technique appeared to be more secure than the TCL technique. The presence of the SC joint did not have an observable influence on test results.

Different Stabilization Techniques for Type 62B3 Acetabular Fractures in Combination With Primary Total Hip Arthroplasty in Elderly Patients: A Biomechanical Comparison.

INTRODUCTION: The total hip arthroplasty (THA) as part of acute fracture management is used for acetabular fractures in elderly patients. Our objective was to assess the stability of osteosynthesis performed using 2 different techniques in combination with THA in an experimental model. MATERIALS AND METHODS: We conducted 20 experiments using the left-side hemipelves composite bone models. There were 2 testing groups: 1- and 2-stage osteosynthesis. The acetabular fractures of the anterior column and posterior hemitransverse were simulated. The same THA technique was used in both groups. The stability of osteosynthesis was explored and compared between the groups by measuring the fracture displacement of anterior and posterior columns under the standardized test load (1187 N) protocol. Load distance diagrams were generated. RESULTS: The 0.680-mm gap (0.518; 1.548) of the posterior column in the 1-stage group (n = 10) was higher than the 0.370-mm gap (0.255; 0.428) in the 2-stage group (n = 10; P = .002). There was no significant difference between the gap of the anterior column in the 1- and 2-stage groups (0.135 [0.078; 0.290] mm vs 0.160 [0.120; 0.210] mm; P = .579). CONCLUSION: The 2-stage osteosynthesis of the anterior and posterior columns in combination with THA provides better stability of posterior column when compared to 1-stage method in composite bone models.

Research of the spatial-temporal gait parameters and pressure characteristic in spastic diplegia children.

PURPOSE: Spastic diplegia is the most common form of cerebral palsy. It presents with symmetric involvement of the lower limbs and upper limbs. Children with spastic diplegia frequently experience problems with motor control, spasticity, and balance which lead to gait abnormalities. The aim of this study is twofold. Firstly, to determine the differences in spatial-temporal gait parameters and magnitude of plantar pressure distribution between children with spastic diplegia (CP) and typical children. Secondly, to compare and evaluate main changes of plantar pressure and spatial-temporal gait parameters instead of data between spastic diplegia children with prescribed ankle - solid foot orthosis (AFOs) and without using AFOs. METHODS: The evaluation was carried out on 20 spastic diplegia children and 10 agematched children as a control group aged 6-15 years. Twenty children with spastic diplegia CP were divided into two groups: ten subjects with prescribed AFOs and ten subjects without use of assistive device. Patients used the AFOs orthosis for one year. Measurements included in-shoe plantar pressure distribution and spatial-temporal gait parameters. RESULTS: Spatial-temporal gait parameters showed meaningful difference between study groups in velocity, stride length, step length and cadence ( p < 0.05). However no significant differences between patients with and without AFOs were found ( p > 0.05). Significant differences between typical and spastic diplegia children with AFOs were observed in the magnitude of plantar pressure under the toes, the metatarsal heads, the medial arch, and the heel ( p < 0.05). For typical subjects, the highest pressure amplitudes were found under the heel and the metatarsal heads, while the lowest pressure distribution was under the medial arch. In CP patients the lateral arch was strongly unloaded. The peak pressure under heel was shifted inside. CONCLUSIONS: Collected data and calculated scores present a state of the gait in test groups, showed the difference and could be valuable for physicians in decision making by choosing qualitative therapy. Furthermore, it allows predicting probability of further possible changes in gait of spastic diplegia patients with AFOs and without it. In conclusion, our current results showed that the use of AFOs, prescribed on a clinical basis by doctors improves gait patterns and gait stability in children with spastic cerebral palsy.

Investigation of mutual aerobic and lower limb muscular activity during cycling.

The evaluation of physical activity is a complex task that requires performing an analysis of muscular activity and aerobic/anaerobic threshold and it is often difficult to observe and propose a single method. The purpose of the article is to evaluate a relation between aerobic capacity and activity of lower limb muscles via changes of muscle's EMG signal during physical, sub-maximal veloergometric loading. The activity parameters of 5 lower limb muscles such as semitendinosus, rectus femoris, biceps femoris, gastrocnemius medialis, and tibialis anterior were measured and analyzed during the veloergometric exercise tests and the heart rate and the aerobic capacity were estimated from registered data. The obtained aerobic parameters allow setting an individual and overall voluntary physical capacity. The regression oxygen function presented allows analyzing and predicting the ability of subjects to generate energy while maintaining muscle activity during the exercise. The correlation between the consumption of oxygen and constant physical loading time is determined. It was found that comparing VO2max capabilities the physical effort in the male group was 16% higher than in women. Oxygen consumption and maximum muscle effort dependency on the load time was established. It was observed that the maximal muscular effort appeared before VO2max reached maximal limit in both groups. The maximal oxygen consumption is achieved in the middle or sometimes at the beginning (depending on load) of exercise while maximal muscular effort was found in several phases of cycling: at the beginning and at the end of loading time.

Research of cyclist's spine dynamical model.

The purpose of the paper is to present a dynamic model of bicyclist's lumbar spine for the evaluation of linear and angular variation of intervertebral distance in sagittal plane. Ten degrees of freedom biomechanical model of the spine was solved numerically. Larger loads acting on a cyclist spine occur mostly while sitting in a sport position in comparison with recreation or middle sitting. The load on lumbar spine region is influenced by cycle's tire pressure, road bumps and wheeling speed. The biggest linear and angular displacements were found between L4-L5 vertebras. The biggest load protractile spine muscle experiences in the sport sitting position. Maximum vertebrae rotation and linear variation values in wheeling regime with 1.5 Bar tyres pressure and at a speed of 10 km/h are 0.46° and 0.46 mm. Maximum vertebrae rotation and linear variation values for a 23 year old, 1.74 m high and 73 kg of mass (bicycle mass~7 kg) man in wheeling regime with 3.5 Bar tyres pressure and at a speed of 30 km/h are 3.9° and 1.23 mm. The biggest variation of rotation in sagittal plane between two nearest lumbar spines is about 1°. Because of this displacement the frontal part of last mentioned disc is compressed with 530 N more and dorsal disc part as much less.

Analysis of the plantar pressure distribution in children with foot deformities.

This paper describes the method of measuring and assessing the pressure distribution under typical feet and the feet of patients with deformities such as: planovalgus, clubfoot, and pes planus using a pedobarograph. Foot pressure distribution was measured during static and walking at individual normal walking speed. Time-series pressure measurements for all sensors were grouped into five anatomical areas of human foot. In typical subjects, the heel was the first part of the foot receiving the loading of the body. Then it moved to the toe through the midfoot and the metatarsal area. The highest mean pressure in typical subjects was found under the heel and the metatarsal heads. The lowest pressure distribution was under the cuboid bone. In the planovalgus subjects, a higher pressure distribution was found under cuboid bone compared to typical one. In the pes cavus subjects, the pressure distribution was lower under all parts of foot. In the clubfoot subjects, the pressure distribution, the contact area of each mask, and the time of foot contact area in left and right foot are respectively different.