Markerless motion capture affects talocrural joint frontal plane interpretation.

Subtalar instability is associated with up to 80% of patients presenting with chronic ankle instability but is often not considered in the diagnosis or treatment. Operative procedures to repair ankle instability have shown good clinical results, but the effects of these reconstruction procedures on isolated subtalar instability are not well understood. The goal of this study was to investigate the effect of the Gould modification of the Broström procedure and a new tenodesis reconstruction procedure on ankle and subtalar joint kinematics after simulating a subtalar injury. Kinematic data were collected on 7 cadaveric ankles during inversion through the range of ankle flexion and during internal rotation. Testing was performed on the intact foot; after sectioning the calcaneofibular ligament, cervical ligament, and interosseous talocalcaneal ligament; after the Gould modification of the Broström procedure was performed; and after tenodesis was performed and sutures from the Gould modification removed. The Gould modification of the Broström procedure significantly decreased subtalar and ankle inversion motion and subtalar internal rotation compared to the unstable condition. The tenodesis method restricted internal rotation at the subtalar joint and ankle inversion compared to the intact state. Both operative procedures improved stability of the ankle complex, but tenodesis was unable to restore subtalar inversion and restricted ankle inversion in maximum plantarflexion. The Gould modification of Broström ligament repair may be a favorable operative procedure for the restoration of subtalar and ankle joint kinematics.

The purpose of this study was to assess the subtalar joint's kinematics in in the frontal plane (inversion-eversion) using 3D weightbearing cone beam computed tomography by measuring both translational and angular range of motion. In this cohort study, weightbearing cone beam computed tomography images were acquired of 41 subjects under weightbearing stress in 20 degrees inversion and 10 degrees eversion tilt, achieved with hard plastic wedges. The ankle was in neutral position, and the sole of the foot was entirely on the wedge. Interobserver and intraobserver reliability were assessed using intraclass correlation coefficients. All the measured numeric range of motion values in the normal subtalar joint's bony structures were small; however, values were larger in eversion than in inversion. Translational range of motion in the middle facet (1.4 mm) is smaller than in the anterior facet (4.9 mm). Reliability was good to excellent for most parameters; however, several showed poor reliability-particularly interobserver agreement for inversion measures of the middle-facet angle/translation and select talocrural metrics (midpoint/medial joint-space width, joint angle). This study defines the subtalar joint's translational and angular range of motion in the frontal plane (inversion-eversion) under weightbearing stress in normal subtalar joint's bony structures. The applicability of the method should be investigated in different patient groups.

Isolated subtalar and talonavicular joint arthrodeses have been associated with adjacent joint arthritis and altered hindfoot kinematics during simplified loading scenarios. However, the effect on kinematics during dynamic activity is unknown. This study assessed changes in subtalar and talonavicular kinematics after isolated talonavicular (TNiso) and subtalar (STiso) arthrodesis, respectively, during stance simulations. Fourteen midtibia specimens received either a TNiso or STiso arthrodesis, with 7 randomized to each group. A 6-degree-of-freedom robot sequentially simulated the stance phase for the intact and arthrodesis conditions. Bootstrapped bias-corrected 95% CIs of the talonavicular and subtalar joint kinematics were calculated and compared between conditions. The TNiso decreased subtalar inversion, adduction, and plantarflexion in late stance (P < .05). The subtalar range of motion in the sagittal and coronal planes decreased by 40% (P = .009) and 46% (P = .002), respectively. No significant changes in talonavicular joint kinematics were observed after isolated subtalar arthrodesis; however, the range of motion was reduced by 61% (P = .007) and 50% (P = .003) in the coronal and axial planes, respectively. In this model for arthrodesis, changes in subtalar kinematics and motion restriction were observed after isolated talonavicular arthrodesis, and motion restriction was observed after isolated subtalar arthrodesis. Surprisingly, talonavicular kinematics did not appear to change after isolated subtalar arthrodesis. Both joint fusions substantially decrease the motion of the reciprocal adjacent joint. Surgeons should be aware that the collateral costs with talonavicular fusion appear higher, and it has a significant effect on subtalar kinematics during the toe-off phase of gait.

Objective To investigate the value of statistical parametric mapping (SPM) analysis of 18F-fluorodeoxyglucose (FDG) PET imaging in the differential diagnosis of Parkinsonism in single-case level. Methods SPM software was used to retrospectively analyze the 18F-FDG PET images of 160 patients (104 males, 56 females, age: 30-82 years) who were suspected with Parkinsonism at baseline and were clinical confirmed by follow-up from April 2010 to December 2017. 18F-FDG PET images of patients was compared with those of age-matched healthy controls in single-case level using two-sample t test in SPM software to obtain the imaging diagnosis. By comparing imaging diagnosis with the final clinical diagnosis, the diagnostic accuracy of SPM in the overall cohort as well as the early subcohort (duration of disease less than 2 years (56 males, 22 females, age: 50-82 years)) were calculated respectively. Results Among 160 patients with Parkinsonism, 146(91.2%) had the same 18F-FDG PET diagnosis as their final clinical diagnosis. The diagnostic sensitivity for Parkinson′s disease (PD), multiple system atrophy (MSA), progressive supranuclear palsy (PSP) and cortical basal ganglia degeneration (CBD) were 93.5%(86/92), 92.3%(24/26), 84.0%(21/25) and 15/17, respectively. The specificity were 95.6%(65/68), 95.5%(128/134), 96.3%(130/135) and 100%(143/143), respectively. In the early subcohort, the analysis also achieved similar differential diagnosis effectiveness(92.3%). Conclusion The single-case 18F-FDG PET imaging SPM analysis can be helpful in the early differential diagnosis of Parkinsonism effectively. Key words: Parkinsonian disorders; Positron-emission tomography; Diagnosis, differential; Deoxyglucose

The study hypothesised that a markerless motion capture system can provide kinematic data comparable to a traditional marker-based system for riders mounted on a horse. The objective was to assess the markerless system's accuracy by directly comparing joint and segment angle measurements taken during walking and trotting with those obtained from a marker-based system. Ten healthy adult participants performed five dynamic trials during walking and trotting. A twelve-camera marker-based system and eight-camera 2D video-based system were synchronised. Three-dimensional hip, knee, shoulder and elbow joint angles, and the global trunk and pelvis angle were computed for comparison between the two systems. To assess the error between systems, the root mean square difference (RMSD) was averaged across each gait cycle and statistical parametric mapping (SPM) paired t-tests were applied. The sagittal trunk angle had the lowest RMSD of 2.0° and elbow rotation had the highest RMSD of 19°, with the same values for walking and trotting. SPM indicated increased hip flexion (0-100%, p<0.001) and elbow flexion (24-47%, p=0.03; 63-100%, p<0.001) in the walking gait cycle for the markerless system. A lack of joint range of motion and obscured medial limbs during walking whilst mounted on horses may cause increased offsets for markerless data in equestrian riders. No significant differences were found for the transverse plane, yet there tended to be increased RMSD. This lack of consistency suggests results from the transverse plane in equestrian riders should be interpreted with caution. Study findings indicate that markerless technology has the potential to be a suitable alternative to marker-based systems for assessment of equestrian riders, dependent on the segment/joint angle of interest and the level of acceptable error. These results indicate that markerless systems can effectively be utilised for rider biofeedback, though their application may be limited for specific joint analyses.

Experimental evaluation of iterative reconstruction versus filtered back projection for 3D [ 15O]water PET activation studies using statistical parametric mapping analysis

In this paper, we utilized functional near-infrared spectroscopy (fNIRS) technology to examine the hemodynamic responses in the motor cortex for two conditions, namely standing and sitting tasks. Nine subjects performed five trials of standing and sitting (SAS) tasks with both real movements and imagery thinking of SAS. A group level of statistical parametric mapping (SPM) analysis during these tasks showed bilateral activation of oxy-hemoglobin for both real movements and imagery experiments. Interestingly, the SPM analysis clearly revealed that the sitting tasks induced a higher oxy-hemoglobin level activation compared to the standing task. Remarkably, this finding is persistent across the 22 measured channels at the individual and group levels for both experiments. Furthermore, six features were extracted from pre-processed HbO signals and the performance of four different classifiers was examined in order to test the viability of using SAS tasks in future fNIRS-brain-computer interface (fNIRS-BCI) systems. In particular, two features-combination tests revealed that the signal slope with signal variance represents one of the three best two-combined features for its consistency in providing high accuracy results for both real and imagery experiments. This study shows the potential of implementing such tasks into the fNIRS-BCI system. In the future, the results of this work could pave the way towards the application of fNIRS-BCI in lower limb rehabilitation.

BackgroundSynergetic talocrural and subtalar joint movements allow adaptation to different footwear and/or surface conditions. Therefore, knowledge of kinematic differences between barefoot and shod conditions is valuable for the study of adaptations to footwear conditions. The objective of this study was to assess the kinematic differences in the talocrural and subtalar joints during barefoot and shod landing.MethodsSeven healthy participants (4 males and 3 females) participated in a landing trial under barefoot and shod conditions. Fluoroscopic images and forceplate data were collected simultaneously to calculate the talocrural and subtalar joint kinematics and the vertical ground reaction force.ResultsUpon toe contact, the plantarflexion angle of the talocrural joint during the barefoot condition was significantly larger than that during the shod condition (barefoot, 20.5 ± 7.1°, shod, 17.9 ± 8.3°, p =0.03). From toe contact to heel contact, the angular changes at the talocrural and subtalar joint were not significantly different between the barefoot and shod conditions; however, the changes in the subtalar eversion angles in the barefoot condition, from heel contact to 150 ms after toe contact, were significantly larger than those in the shod condition.ConclusionsThese results suggest that footwear was able to reduce the eversion angle of the subtalar joint after heel contact during landing; the effect of wearing footwear was quite limited. Therefore, induced rearfoot kinematic alterations to prevent or manage injuries by neutral-type footwear are likely to be impractical.

Statistical parametric mapping (SPM) quantification and analysis has been successfully applied to functional imaging studies of partial epilepsy syndromes in adults. The present study evaluated whether localisation of the epileptogenic zone (determined by SPM) improves upon visually examined single-photon emission tomography (SPET) imaging in presurgical assessment of children with temporal lobe epilepsy (TLE) and frontal lobe epilepsy (FLE). The patient sample consisted of 24 children (15 males) aged 2.1-17.8 years (9.8+/-4.3 years; mean+/-SD) with intractable TLE or FLE. SPET imaging was acquired routinely in presurgical evaluation. All patient images were transformed into the standard stereotactic space of the adult SPM SPET template prior to SPM statistical analysis. Individual patient images were contrasted with an adult control group of 22 healthy adult females. Resultant statistical parametric maps were rendered over the SPM canonical magnetic resonance imaging (MRI). Two corresponding sets of ictal and interictal SPM and SPET images were then generated for each patient. Experienced clinicians independently reviewed the image sets, blinded to clinical details. Concordance of the reports between SPM and SPET images, syndrome classification and MRI abnormality was studied. A fair level of inter-rater reliability (kappa=0.73) was evident for SPM localisation. SPM was concordant with SPET in 71% of all patients, the majority of the discordance being from the FLE group. SPM and SPET localisation were concordant with epilepsy syndrome in 80% of the TLE cases. Concordant localisation to syndrome was worse for both SPM (33%) and SPET (44%) in the FLE group. Data from a small sample of patients with varied focal structural pathologies suggested that SPM performed poorly relative to SPET in these cases. Concordance of SPM and SPET with syndrome was lower in patients younger than 6 years than in those aged 6 years and above. SPM is effective in localising the potential epileptogenic zone but does not provide additional benefit beyond SPET in presurgical assessment of children with intractable epilepsy. The impact of different pathologies on the efficacy of SPM warrants further study.

Lower limb alignment and specifically the hip-knee-ankle-angle (HKAA), is increasingly being recognized as an important factor in operative planning for total knee arthroplasty (TKA) for patients with knee osteoarthritis (OA). Current clinical practice is to measure alignment from weight bearing radiographs. This static measurement may differ from alignment during the weightbearing stance phase of gait. Markerless motion capture is a novel biomechanical assessment tool that uses off-the-shelf video cameras to capture whole-body movements. The objective of our study was to evaluate HKAA during static and dynamic tasks for patients with predominantly medial or lateral knee OA. Patients diagnosed with knee OA were recruited from advanced care physiotherapists at an outpatient hospital. Markerless motion capture was used to measure whole body movements during a quiet standing task and during gait using eight synchronized Sony RX0 II video cameras at 60 Hz (Sony, Minato, Japan). During quiet stand, subjects stood upright with their feet facing forward and shoulder-width apart for thirty seconds. Gait was assessed during overground walking at a self-selected speed for one minute. Video data was processed with Theia3D (v. 2023.01.0.361 p7, Theia Markerless Inc. Kingston, ON). Visual3D (C-Motion, Germantown, MD) was used to provide gait event detection and estimate hip, knee, and ankle joint locations in three-dimensions at each frame. HKAA was calculated from the three-dimensional joint locations in the frontal plane. For the static quiet standing task, HKAA was averaged over the first five seconds of the standing task. During gait, dynamic HKAA was calculated as the peak angle prior to terminal stance. Correlation between static and dynamic HKAA were calculated and compared using the Bland and Altman approach. Classification of medial or lateral knee OA was done by an orthopaedic surgeon via radiographic evaluation. Dynamic HKAA was compared between medial and lateral knee OA patients (t-test). Static and dynamic HKAA were assessed for 160 knees in 102 patients (34 male, 68 female, mean age 67 years (SD 9)). The static HKAA from the quiet standing task (mean = 182.7 degrees, SD = 4.2) and the peak dynamic HKAA from the gait task (mean = 184.7 degrees SD = 4.6) were highly correlated (Pearson's r = 0.88, p &lt; 0.001). Dynamic HKAA was on average two degrees more varus . Dynamic HKAA was significantly more varus for patients with medial OA (mean 185.9 degrees) than those with lateral OA (mean 176.7 degrees, p &lt; 0.001, t-test). Dynamic peak HKAA measured with markerless motion capture was found to be strongly correlated with static HKAA. Markerless motion capture provides an alternative, low burden, radiation free assessment tool with high potential for clinical integration. The ability to assess dynamic tasks and dynamic parameters, such as HKAA throughout gait, means that markerless motion capture has the potential to provide enhanced assessments pre- and post-TKA.

Statistical Parametric Mapping (SPM) is a computational approach for analysing functional brain images like Positron Emission Tomography (PET). When performing SPM analysis for different patient populations, brain PET template images representing population-specific brain morphometry and metabolism features are helpful. However, most currently available brain PET templates were constructed using the Caucasian data. To enrich the family of publicly available brain PET templates, we created Chinese-specific template images based on 116 [18F]-fluorodeoxyglucose ([18F]-FDG) PET images of normal participants. These images were warped into a common averaged space, in which the mean and standard deviation templates were both computed. We also developed the SPM analysis programmes to facilitate easy use of the templates. Our templates were validated through the SPM analysis of Alzheimer’s and Parkinson’s patient images. The resultant SPM t-maps accurately depicted the disease-related brain regions with abnormal [18F]-FDG uptake, proving the templates’ effectiveness in brain function impairment analysis.

Cardan sequence selection influences subtalar and talonavicular joint kinematics.

Only one large series using statistical parametric mapping (SPM) reports on FDG-PET in sporadic (Heidenhain and non-Heidenhain variant) Creutzfeldt-Jakob disease (sCJD), describing hypometabolism in bilateral parietal, frontal, and occipital cortices. Our aim was to study FDG-PET in non-Heidenhain probable sCJD patients in order to assess the most pertinent FDG-PET pattern, and to compare FDG-PET and MRI data. We used both SPM and NeuroGam(®) software analysis, compared with healthy controls, to describe the FDG-PET abnormalities. Individual FDG-PET and MRI-DWI data were compared. SPM group analysis showed lateralized hypometabolism in the medial parietal cortex, the lateral and medial frontal (sparing Brodmann's area 4 and 6 and the anterior cingulate cortex), and lateral parietal cortex, in the absence of basal ganglia or cerebellar hypometabolism. The most severe hypometabolism was seen in Brodmann's area 31, and to a lesser degree area 23 (both areas correspond to the posterior cingulate cortex) and the precuneus. On individual analysis using NeuroGam(®) software, additional variable temporal cortex and frequent basal ganglia (with caudate nucleus as the most frequently involved structure) hypometabolism was seen, in the absence of cerebellar hypometabolism. The cerebral lobe cortex was more frequently and more severely hypometabolic than basal ganglia structures. Concordance between FDG-PET and MRI abnormalities was most often present for both the cerebral lobe cortex and the basal ganglia. In the case of discordance, FDG-PET was more sensitive than MRI for the cortex, whereas MRI was more sensitive than FDG-PET for the basal ganglia. When pathological, both cortical lobe cortex and basal ganglia involvement were slightly more often lateralized on FDG-PET than on MRI. Despite the presence of overlapping features with other diseases presenting with rapidly progressive dementia, the FDG-PET pattern we found in our non-Heidenhain sCJD patients may help in the differential diagnosis of rapidly progressive dementia.

Statistical parametric mapping (SPM) and statistical probabilistic anatomical mapping (SPAM) were applied to basal/acetazolamide Tc-99m ECD brain perfusion SPECT images in patients with middle cerebral artery (MCA) stenosis to assess the efficacy of endovascular stenting of the MCA. Enrolled in the study were 11 patients (8 men and 3 women, mean age 54.2 +/- 6.2 years) who had undergone endovascular stent placement for MCA stenosis. Using SPM and SPAM analyses, we compared the number of significant voxels and cerebral counts in basal and acetazolamide SPECT images before and after stenting, and assessed the perfusion changes and cerebral vascular reserve index (CVRI). The numbers of hypoperfusion voxels in SPECT images were decreased from 10,083 +/- 8,326 to 4,531 +/- 5,091 in basal images (P = 0.0317) and from 13,398 +/- 14,222 to 7,699 +/- 10,199 in acetazolamide images (P = 0.0142) after MCA stenting. On SPAM analysis, the increases in cerebral counts were significant in acetazolamide images (90.9 +/- 2.2 to 93.5 +/- 2.3, P = 0.0098) but not in basal images (91 +/- 2.7 to 92 +/- 2.6, P = 0.1602). The CVRI also showed a statistically significant increase from before stenting (median 0.32; 95% CI -2.19-2.37) to after stenting (median 1.59; 95% CI -0.85-4.16; P = 0.0068). This study revealed the usefulness of voxel-based analysis of basal/acetazolamide brain perfusion SPECT after MCA stent placement. This study showed that SPM and SPAM analyses of basal/acetazolamide Tc-99m brain SPECT could be used to evaluate the short-term hemodynamic efficacy of successful MCA stent placement.

A sensitive data analysis approach for detecting changes in dynamic postural stability