Definition of anatomical zero positions for assessing shoulder pose with 3D motion capture during bilateral abduction of the arms

Background: Surgical interventions at the shoulder may alter function of the shoulder complex. Clinically, the outcome can be assessed by universal goniometry. Marker-based motion capture may not resemble these results due to differing angle definitions. Methods: The clinical inspection of bilateral arm abduction for assessing shoulder dysfunction is performed with a marker based 3D optical measurement method. An anatomical zero position of shoulder pose is proposed to determine absolute angles according to the Neutral-0-Method as used in orthopedic context. Static shoulder positions are documented simultaneously by 3D marker tracking and universal goniometry in 8 young and healthy volunteers. Repetitive bilateral arm abduction movements of at least 150° range of motion are monitored. Similarly a subject with gleno-humeral osteoarthritis is monitored for demonstrating the feasibility of the method and to illustrate possible shoulder dysfunction effects. Results: With mean differences of less than 2°, the proposed anatomical zero position results in good agreement between shoulder elevation/depression angles determined by 3D marker tracking and by universal goniometry in static positions. Lesser agreement is found for shoulder pro-/retraction with systematic deviations of up to 6°. In the bilateral arm abduction movements the volunteers perform a common and specific pattern in clavicula-thoracic and gleno-humeral motion with maximum shoulder angles of 32° elevation, 5° depression and 45° protraction, respectively, whereas retraction is hardly reached. Further, they all show relevant out of (frontal) plane motion with anteversion angles of 30° in overhead position (maximum abduction). With increasing arm anteversion the shoulder is increasingly retroverted, with a maximum of 20° retroversion. The subject with gleno-humeral osteoarthritis shows overall less shoulder abduction range of motion but with increased out-of-plane movement during abduction. Conclusions: The proposed anatomical zero definition for shoulder pose fills the missing link for determining absolute joint angles for shoulder elevation/depression and pro-/retraction. For elevation-/depression the accuracy suits clinical expectations very well with mean differences less than 2° and limits of agreement of 8.6° whereas for pro-/retraction the accuracy in individual cases may be inferior with limits of agreement of up to 24.6°. This has critically to be kept in mind when applying this concept to shoulder intervention studies

The Variable Influence of Orthotic Management on Hip and Pelvic Rotation in Children with Unilateral Neurogenic Equinus Deformity

BACKGROUND Equinus deformity with or without concomitant drop foot is a common finding in children with unilateral spastic cerebral palsy and spastic hemiplegia of other causes. Hypothetically, these deformities may lead to pelvic retraction and hip internal rotation during gait. Orthoses are used to reduce pes equinus during gait and to restore hindfoot first contact. OBJECTIVE We aimed to investigate whether the use of orthotic equinus correction reduces rotational hip and pelvic asymmetries. METHODS In a retrospective study, 34 children with unilateral spastic cerebral palsy or spastic hemiplegia of other causes underwent standardized instrumented 3D gait analysis with and without orthotic equinus management. We analyzed the differences in the torsional profile during barefoot walking and while wearing orthoses, as well as investigated the influence of ankle dorsiflexion and femoral anteversion on pelvic and hip kinematics and hip kinetics. RESULTS Wearing orthoses corrected pes equinus and pelvic internal rotation at the end of the stance phase and in the swing phase compared to barefoot walking. Hip rotation and the rotational moment did not significantly change with orthoses. Orthotic management or femoral anteversion did not correlate to pelvic and hip asymmetry. CONCLUSION The findings indicate that the correction of the equinus by using orthoses had a variable effect on the asymmetry of the hip and pelvis and internal rotation; both appear to have a multifactorial cause that is not primarily driven by the equinus component

Prediction of Antibiotic Susceptibility Profiles of Vibrio cholerae Isolates From Whole Genome Illumina and Nanopore Sequencing Data: CholerAegon

During the last decades, antimicrobial resistance (AMR) has become a global public health concern. Nowadays multi-drug resistance is commonly observed in strains of Vibrio cholerae, the etiological agent of cholera. In order to limit the spread of pathogenic drug-resistant bacteria and to maintain treatment options the analysis of clinical samples and their AMR profiles are essential. Particularly, in low-resource settings a timely analysis of AMR profiles is often impaired due to lengthy culturing procedures for antibiotic susceptibility testing or lack of laboratory capacity. In this study, we explore the applicability of whole genome sequencing for the prediction of AMR profiles of V. cholerae. We developed the pipeline CholerAegon for the in silico prediction of AMR profiles of 82 V. cholerae genomes assembled from long and short sequencing reads. By correlating the predicted profiles with results from phenotypic antibiotic susceptibility testing we show that the prediction can replace in vitro susceptibility testing for five of seven antibiotics. Because of the relatively low costs, possibility for real-time data analyses, and portability, the Oxford Nanopore Technologies MinION sequencing platform-especially in light of an upcoming less error-prone technology for the platform-appears to be well suited for pathogen genomic analyses such as the one described here. Together with CholerAegon, it can leverage pathogen genomics to improve disease surveillance and to control further spread of antimicrobial resistance.We thank Dr. Daniel Cadar and Heike Baum from the NGS core facility of the Bernhard Nocht Institute for Tropical Medicine for technical support. We thank the Carl-Zeiss-Stiftung (FKZ 0563-2.8/738/2), TWMMG DigLeben (5575/10-9), and DFG iDIV (FZT 118, 202548816) for financial support. Figures were finalized with Inkscape v1.0.2.S

Performance of stair negotiation in patients with cerebral palsy and stiff knee gait

Background Due to the limited knee range of motion, achieving adequate foot clearance while walking on level ground constitutes a major problem for patients with cerebral palsy and stiff knee gait. Stair negotiation as an activity of daily life requires a considerably higher knee range of motion than level ground walking, but little is known yet as to whether such patients are able to walk stairs. Research question: The aim of this study was to investigate how patients with a limited knee range of motion negotiate stairs. Do they increase their peak knee flexion and use the same pattern as in walking on level ground? How do the muscles act during stair negotiation? Methods In this explorative study, 17 adults with bilateral, spastic cerebral palsy and stiff knee gait and 25 healthy subjects were examined. 3D motion analysis, including electromyography, was performed while walking on level ground, upstairs, and downstairs. A linear mixed model was used for between- and within-group comparisons. Results Walking upstairs and downstairs, patients increased their peak knee flexion by around 30° compared to level walking. Thus, increased knee flexion may be seen as the main mechanism for maintaining foot clearance on stairs. An increased pelvic obliquity (elevation) and hip flexion were also found and involved subjects showed a slight increase in rectus femoris activity when walking on stairs compared to level walking within the phases of high knee flexion. Significance This study showed that patients with cerebral palsy and stiff knee gait are able to flex their knees more than would be required for level walking. Hence, the patients are able to adapt their rectus activity to stair walking to some extent. Therefore, further investigations might help to open up new therapeutic options to facilitate level walking and stair negotiation in patients with stiff knee gait

Rasterstereographic Analysis of Lateral Shift in Patients with Lumbar Disc Herniation: A Case Control Study

Objective. Detection of a lateral shift (LS) in patients with diagnosed disc herniation compared to healthy controls. Summary of Background Data. A specific lateral shift (LS) pattern is observed in patients with disc herniation and low back pain, as shown in earlier studies. Methods. Rasterstereography (RS) was used to investigate the LS. Thirty-nine patients with lumbar disc herniation diagnosed by radiological assessment and low back pain and/or leg pain (mean age 48.2 years, mean BMI 28.5, 28 males and 11 females) and 36 healthy controls (mean age 47.4 years, mean BMI 25.7, 25 males and 11 females) were analysed. LS, pelvic tilt, pelvic inclination, lordotic angle, and trunk torsion were assessed. Results. The patient group showed a nonsignificant increase in LS, that is, 5.6 mm compared to the healthy controls with 5.0 mm (p = 0.693). However, significant differences were found between groups regarding pelvic tilt in degrees (patients 5.9°, healthy controls 2.0°; p = 0.016), trunk torsion (patients 7.5°, controls 4.5°; p = 0.017), and lordotic angle (patients 27.5°, healthy controls 32.7°; p = 0.022). The correlation between pain intensity and the FFbH-R amounted 0.804 (p = < 0.01), and that between pain intensity and the pain disability index was 0.785 (p < 0.01). Discussion. Although some studies have illustrated LS with disc herniation and low back pain, the present findings demonstrate no significant increase in LS in the patient group compared to healthy controls. Conclusion. The patients with lumbar disc herniation did not demonstrate an increased LS compared to healthy controls. Other parameters like pelvic tilt and inclination seemed to be more suitable to identify changes in posture measured by RS in patients with low back pain or disc herniation

Effects of artificially induced bilateral internal rotation gait on gait kinematics and kinetics

BACKGROUND Bilateral internal rotation gait is a common gait abnormality in children with bilateral cerebral palsy, but still not fully understood. RESEARCH QUESTION The aim of this clinical study was to analyze the effects of artificially induced bilateral internal rotation gait on kinematics and kinetics. Our hypothesis was, that the internal rotation gait defined as increased dynamic internal hip rotation itself causes significant alterations in gait kinematics and kinetics. METHODS 30 typically developing children with a mean age of 12 (SD 3) years (range 8 - 16) performed three-dimensional gait analysis in two different conditions: with unaffected gait and with artificially induced bilateral internal rotation gait with two rotation bandages worn in order to internally rotate the hips. Kinematic and kinetic changes between these two conditions were calculated and compared using a mixed linear model with "gait condition" as fixed effect and both "limb" and "patient" as random effects. RESULTS The rotation bandages induced a significant increase in internal hip rotation and foot progression angle towards internal without affecting pelvic rotation. The peak hip internal rotator moment during loading response and the peak hip external rotator moment during the first half of stance phase increased significantly and the peak hip internal rotator moment during the second half of stance phase decreased significantly. Anterior pelvic tilt, hip flexion, knee flexion and ankle dorsiflexion increased significantly. The first peak of the frontal hip moment decreased, and the second increased significantly. The second peak of the frontal knee moment decreased significantly, while the first didn't change significantly. SIGNIFICANCE The data suggest, that the bilaterally increased dynamic internal hip rotation itself has a relevant impact on frontal hip moments. The increased anterior pelvic tilt, hip and knee flexion may be either induced by the pull of the rotation bandage or a secondary gait deviation

Supracondylar femoral rotation osteotomy affects frontal hip kinetics in children with bilateral cerebral palsy

AIM: To evaluate the influence of supracondylar femoral derotation osteotomy (FDO) on hip abduction muscle force and frontal hip moments in children with bilateral cerebral palsy. METHOD: For this retrospective cohort study 79 children (36 females, 43 males; mean age at surgery 11y [SD 3y]; range 4-17y) with bilateral cerebral palsy and preoperatively and 1-year postoperatively documented frontal hip moments who received supracondylar FDO in 134 limbs were included. The control group consisted of eight children (two females, six males; mean age 11y [SD 4y]; range 5-17y) who received single-event multi-level surgery without FDO. RESULTS: Hip joint impulse (p<0.001) and the first peak of frontal hip moments (p=0.003) increased, whereas the second peak decreased (p<0.001) from preoperatively to postoperatively. Hip abductor strength improved (p=0.001) from preoperatively to postoperatively. INTERPRETATION: Despite the compensatory mechanism, frontal hip moments are decreased preoperatively. Supracondylar FDO results in increased frontal hip moments. Changes in anteversion directly influence hip kinetics, although no direct change of the proximal bony geometry is performed

The Variable Influence of Orthotic Management on Hip and Pelvic Rotation in Children with Unilateral Neurogenic Equinus Deformity

Background: Equinus deformity with or without concomitant drop foot is a common finding in children with unilateral spastic cerebral palsy and spastic hemiplegia of other causes. Hypothetically, these deformities may lead to pelvic retraction and hip internal rotation during gait. Orthoses are used to reduce pes equinus during gait and to restore hindfoot first contact. Objective: We aimed to investigate whether the use of orthotic equinus correction reduces rotational hip and pelvic asymmetries. Methods: In a retrospective study, 34 children with unilateral spastic cerebral palsy or spastic hemiplegia of other causes underwent standardized instrumented 3D gait analysis with and without orthotic equinus management. We analyzed the differences in the torsional profile during barefoot walking and while wearing orthoses, as well as investigated the influence of ankle dorsiflexion and femoral anteversion on pelvic and hip kinematics and hip kinetics. Results: Wearing orthoses corrected pes equinus and pelvic internal rotation at the end of the stance phase and in the swing phase compared to barefoot walking. Hip rotation and the rotational moment did not significantly change with orthoses. Orthotic management or femoral anteversion did not correlate to pelvic and hip asymmetry. Conclusion: The findings indicate that the correction of the equinus by using orthoses had a variable effect on the asymmetry of the hip and pelvis and internal rotation; both appear to have a multifactorial cause that is not primarily driven by the equinus component