Robot-assisted training after proximal humeral fracture: A randomised controlled multicentre intervention trial.

OBJECTIVE: To examine whether robotic-assisted training as a supplement to usual therapy is safe, acceptable and improves function and patient reported outcome after proximal humeral fractures (PHF). DESIGN: Multicentre, assessor-blinded, randomised controlled prospective trial. SETTING: Three different rehabilitation hospitals in Germany. SUBJECTS: In total 928 PHF patients between 35 and 70 years were screened. Forty-eight participants were included in the study (intervention group n = 23; control group n = 25). INTERVENTION: The control group received usual occupational and physiotherapy over three weeks, and the intervention group received additional 12 robot-assisted training sessions at the ARMEO®-Spring. MAIN MEASURES: Disabilities of the Arm, Shoulder and Hand Questionnaire (DASH), the Wolf Motor Function Test-Orthopaedic, active range of motion and grip strength were determined before and after intervention period. The DASH was additionally obtained postal 6 and 13 months following surgery. RESULTS: The mean age of participants was 55 ± 10 years and was similar in both groups (p > 0.05). The change in DASH as the primary endpoint in the intervention group after intervention was -15 (CI = 8-22), at follow-up six month -7 (CI = -2 to 16) at follow up 13 month -9 (CI = 1-16); in control group -14 (CI = 11-18), at follow-up six month -13 (CI = 7-19) at follow up 13 month -6 (CI = -3 to 14). No difference in the change was found between groups (p > 0.05). None of the follow-up time points demonstrated an additional benefit of the robotic therapy. CONCLUSION: The additional robot-assisted therapy was safe, acceptable but showed no improvement in functional shoulder outcome compared to usual therapy only.

Inter-rater reliability, sensitivity to change and responsiveness of the orthopaedic Wolf-Motor-Function-Test as functional capacity measure before and after rehabilitation in patients with proximal humeral fractures.

BACKGROUND: The incidence of proximal humeral fractures (PHF) increased by more than 30% over the last decade, which is accompanied by an increased number of operations. However, the evidence on operative vs. non-operative treatment and post-operative treatments is limited and mostly based on expert opinion. It is mandatory to objectively assess functional capacity to compare different treatments. Clinical tools should be valid, reliable and sensitive to change assessing functional capacity after PHFs. This study aimed to analyse inter-rater reliability of the videotaped Wolf-Motor-Function-Test-Orthopaedic (WMFT-O) and the association between the clinical WMFT-O and the Disability of the Arm, Shoulder and Hand (DASH) and to determine the sensitivity to change of the WMFT-O and the DASH to measure functional capacity before and after rehabilitation in PHF patients. METHODS: Fifty-six patients (61.7 ± 14.7 years) after surgical treatment of PHF were assessed using the WMFT-O at two different time points. To determine inter-rater reliability, the videotaped WMFT-O was evaluated through three blinded raters. Inter-rater agreement was determined by Fleiss' Kappa statistics. Pearson correlation coefficients were calculated to assess the association between the clinical WMFT-O and the video rating as well as the DASH. Sensitivity to change and responsiveness were analysed for the WMFT-O and the DASH in a subsample of forty patients (53.8 ± 1.4 years) who were assessed before and after a three week robotic-assisted training intervention. RESULTS: Inter-rater agreement was indicated by Fleiss' Kappa values ranging from 0.33-0.66 for functional capacity and from 0.27-0.54 for quality of movement. The correlation between the clinical WMFT-O and the video rating was higher than 0.77. The correlation between the clinical WMFT-O and the DASH was weak. Sensitivity to change was high for the WMFT-O and the DASH and responsiveness was given. In comparison to the DASH, the sensitivity to change of the WMFT-O was higher. CONCLUSION: The overall results indicate that the WMFT-O is a reliable, sensitive and responsive instrument to measure more objectively functional change over time in rehabilitation after PHF. Furthermore, it has been shown that video assessment is eligible for studies to ensure a full blinding of raters. TRIAL REGISTRATION: Clinicaltrials.gov, NCT03100201 . Registered on 28 March 2017. The trial was retrospectively registered.

Dissociating the neural mechanisms of pain consistency and pain intensity in the trigemino-nociceptive system.

BACKGROUND: Individual differences in pain perception to a standardized nociceptive input are a well-known phenomenon within pain research. Brain structures known to play a crucial role in pain modulatory processes are the rostral/subgenual anterior cingulate cortex (sACC) as well as the periaqueductal gray (PAG), which belong to the endogenous antinociceptive system. However, the exact mechanisms possibly leading to this high level of variance in pain perception are still a matter of debate. METHODS: Pain perception within the trigemino-vascular system was investigated in 37 healthy volunteers using functional magnetic resonance imaging. RESULTS: Behavioral results show high levels of variance being inversely correlated to mean pain ratings as well as to an increase in BOLD signal intensity within the sACC. In addition, higher sACC activation was coupled with activation in the PAG the lower the level of intra-individual variance. CONCLUSION: This study gives first indications that coupled BOLD response within brain structures of the antinociceptive system seems to rather not code pain intensity within the trigemino-nociceptive system but the stability of volunteers' pain ratings. Intrinsic mechanisms may modulate the pain perception in the trigemino-vascular system, which is highly involved in headache disorders.

Dissociable contributions of ventromedial prefrontal and posterior parietal cortex to value-guided choice.

Two long-standing traditions have highlighted cortical decision mechanisms in the parietal and prefrontal cortices of primates, but it has not been clear how these processes differ, or when each cortical region may influence behaviour. Recent data from ventromedial prefrontal cortex (vmPFC) and posterior parietal cortex (PPC) have suggested one possible axis on which the two decision processes might be delineated. Fast decisions may be resolved primarily by parietal mechanisms, whereas decisions made without time pressure may rely on prefrontal mechanisms. Here, we report direct evidence for such dissociation. During decisions under time pressure, a value comparison process was evident in PPC, but not in vmPFC. Value-related activity was still found in vmPFC under time pressure. However, vmPFC represented overall input value rather than compared output value. In contrast, when decisions were made without time pressure, vmPFC transitioned to encode a value comparison while value-related parameters were entirely absent from PPC. Furthermore, under time pressure, decision performance was primarily governed by PPC, while it was dominated by vmPFC at longer decision times. These data demonstrate that parallel cortical mechanisms may resolve the same choices in differing circumstances, and offer an explanation of the diverse neural signals reported in vmPFC and PPC during value-guided choice.

Central effects of acetylsalicylic acid on trigeminal-nociceptive stimuli.

BACKGROUND: Acetylsalicylic acid is one of the most used analgesics to treat an acute migraine attack. Next to the inhibitory effects on peripheral prostaglandin synthesis, central mechanisms of action have also been discussed. METHODS: Using a standardized model for trigeminal-nociceptive stimulation during fMRI scanning, we investigated the effect of acetylsalicylic acid on acute pain compared to saline in 22 healthy volunteers in a double-blind within-subject design. Painful stimulation was applied using gaseous ammonia and presented in a pseudo-randomized order with several control stimuli. All participants were instructed to rate the intensity and unpleasantness of every stimulus on a VAS scale. Based on previous results, we hypothesized to find an effect of ASA on central pain processing structures like the ACC, SI and SII as well as the trigeminal nuclei and the hypothalamus. RESULTS: Even though we did not find any differences in pain ratings between saline and ASA, we observed decreased BOLD signal changes in response to trigemino-nociceptive stimulation in the ACC and SII after administration of ASA compared to saline. This finding is in line with earlier imaging results investigating the effect of ASA on acute pain. Contrary to earlier findings from animal studies, we could not find an effect of ASA on the trigeminal nuclei in the brainstem or within the hypothalamic area. CONCLUSION: Taken together our study replicates earlier findings of an attenuating effect of ASA on pain processing structures, which adds further evidence to a possibly central mechanism of action of ASA.

Pharmacological neuroimaging in headache and pain.

PURPOSE OF REVIEW: The current review gives an overview about recent advances in neuroimaging studies with specific emphasis on pharmacological modulation of pain and headache. Further, we want to highlight how imaging methods have changed our understanding of chronic pain and discuss how pharmacological MRI could lead to new insights into underlying mechanisms of headache and pain. RECENT FINDINGS: Several studies from different imaging laboratories have highlighted the outstanding role of imaging in getting a deeper insight regarding the central mechanisms of drugs. Neuroimaging techniques start to unravel how analgesic drugs, antidepressants or NSAIDs act on pain perception and in particular on central pain processes. Furthermore, the studies included in this review show how context dependent drugs act and how differently they reveal their action in the human brain. SUMMARY: Imaging techniques give us the opportunity to gain a better understanding of drug processes in the central nervous system and help to understand where drugs reveal their therapeutic effect. While some substances work on the emotional-affective component of pain, others modulate sensory-discriminative pain pathways. Especially in the field of headache research, still a lot has to be done to understand how preventatives and acute medication modulate the human brain. Future studies should also replicate and extend recent findings.

[Movement analysis in spinal cord injuries : Assistance in clinical decision making]. / Bewegungsanalyse bei Querschnittverletzungen : Hilfestellung in der klinischen Entscheidungsfindung.

For motor incomplete spinal cord injured patients, improvement of walking function is an important aim in the rehabilitation program. In specialized treatment centers, the 6­minute walking test, the 10-meter walking test or the timed-up-and-go test are used as an assessment tool to determine walking ability, but these tests are not able to assess the quality of gait. Marker-based movement analysis can be used as a reliable method to evaluate the gait pattern. This allows an objective assessment of gait quality over time or can be used to support therapy planning. The benefit of such an analysis is presented by means of two case studies.

Indices of extinction-induced "depression" after operant learning using a runway vs. a cued free-reward delivery schedule.

Loss of reward is one of the etiological factors leading to affective disorders, such as major depression. We have proposed several variants of an animal model of depression based on extinction of reinforced behavior of rats. A number of behaviors emitted during extinction trials were found to be attenuated by antidepressant treatment and, thus, qualified as indices of extinction-induced "despair". These include increases in immobility in the Morris water maze and withdrawal from the former source of reward as well as biting behavior in operant chambers. Here, we assess the effects of reward omission on behaviors after learning of (a) a cued free-reward delivery in an operant chamber and (b) food-reinforced runway behavior. Sixty adult male Wistar rats were either trained to receive food reinforcement every 90 s (s) after a 5s lasting cue light (FI 90), or to traverse an alley to gain food reward. Daily drug treatment with either the selective serotonin reuptake inhibitor citalopram or the tricyclic antidepressant imipramine (each 10mg/kg) or vehicle was begun either 25 days (operant chamber) or 3 days (runway) prior to extinction. The antidepressants suppressed rearing behavior in both paradigms specifically during the extinction trials, which indicates this measure as a useful marker of depression-related behavior, possibly indicating vertical withdrawal. In the operant chamber, only marginal effects on operant learning responses during extinction were found. In the runway, the operant learned responses run time and distance to the goal, as well as total distance moved, grooming and quiescence were also influenced by the antidepressants, providing a potential set of markers for extinction-induced "depression" in the runway. Both paradigms differ substantially with respect to the anticipation of reward, behaviors that are learned and that accompany extinction. Accordingly, antidepressant treatment influenced different sets of behaviors in these two learning tasks.

Development of the center of pressure velocity in the healing process after intra-articular calcaneus fractures.

BACKGROUND: Calcaneal fractures are among the most common foot injuries and sometimes develop manifold post-surgical complications. Restricted foot movement is one of the main functional limitations which often persists during long-term rehabilitation. Therefore, it is important to quantitatively monitor the biomechanical foot mobility after calcaneal fracture from an early stage in order to achieve an optimal therapeutic treatment. RESEARCH QUESTION: Evaluation of the Center of Pressure velocity (vCOP) in patients after intrarticular calcaneal fractures during the healing progress from three to 24 months after surgery. METHODS: A total of 20 patients with unilateral calcaneal fracture were investigated by means of pedobarography and marker-based gait analysis at three, six, 12 and 24 months after surgery. Data for vCOP [m/s], maximum external dorsal extension moments during stance (DEmomentstance) and tibiotalar range of motion during mid stance (MS) and terminal stance (TS) were obtained. Functional evaluation was performed using clinical examination (e.g. calf circumference measurements) and patient-reported outcome measures (SF-36). RESULTS: When compared to the healthy side, vCOP of the injured side showed a significant reduction during MS (3 months: 48%, p < 0.001; 6 months: 13%; p = 0.040) and an significant increase during TS (3 months: 110%, p < 0.001; 6 months: 43%, p < 0.001; 12 months: 17%, p = 0.012). DEmomentstance of the fractured foot, showed a significant increase of 80% (p < 0.001) from three to 24 months after surgery, which correlated with vCOP at three and six months after surgery (p < 0.05; vCOP MS: 3 months: r = 0.876, 6 months: r = 0.685; vCOP TS: 3 months: r = -0.554, 6 months r = -0.626). SIGNIFICANCE: vCOP might serve as an indicator for foot mobility and function during the early healing phase after calcaneal fractures. As vCOP can be obtained by pedobarography it is more readily accessible an less costly compared to foot function obtained by marker based gait analysis.

Recovery of gait and function during the first six months after tibial shaft fractures.

BACKGROUND: Tibial shaft fractures require surgical stabilization preferably by intramedullary nailing. Recovery is often unsatisfactory due to limited knee function and pain, resulting in reduced quality of life. The extent of these functional limitations with respect to gait deficits has not been sufficiently recognized. RESEARCH QUESTION: Are there functional limitations during gait and squat performance during the first six months after surgically treated tibial shaft fractures? METHODS: Twenty-three patients (BMI: 24 ± 3, Age:39 ± 15) with tibial shaft fractures and 23 healthy, matched controls (BMI: 24 ± 3, Age: 40 ± 14) were assessed using instrumented motion analysis two, three and six months after surgery. Kinematic and kinetic data of the lower extremities were collected during level walking and squat performance. Data were compared among follow-up time intervals and between groups. RESULTS: Significant improvements were found for all spatiotemporal parameters and most kinetic parameters. Even six months after surgery functional deficits persisted when compared to healthy controls. There were only slight improvements in sagittal knee and ankle kinematics as well as knee moments and power within the follow-up period. A significant difference compared to the healthy controls can still be observed in these parameters. SIGNIFICANCE: Although patients with tibia fractures demonstrated functional improvements over the early course of healing, some residual deficits in lower extremity movement biomechanics were identified at six months post surgery. In particular knee kinematics in squatting as well as knee kinematics and kinetics during walking only recovered incompletely. This result can help explain the often-reported functional limitations. CLINICAL TRIAL REGISTRATION NUMBER: German register for clinical trials (DRKS00023790).

Effects of assistive insole feedback training on immediate and multi-day partial weight bearing retention during walking: A pilot study.

BACKGROUND: Adherence to partial weight bearing (PWB) plays a crucial role in early rehabilitation and motor control. Dynamic biofeedback insole systems provide a supportive function on immediate PWB adherence, while important long-term retention effects and potential advantages to a conventional static training remain unknown. RESEARCH QUESTION: Is acoustic insole feedback training effective for the retention of prescribed PWB adherence and is there any advantage relative to static training using a conventional bathroom scale? Methods Twenty-four volunteers were randomized into two groups receiving biofeedback training (N = 12) via a mobile insole system (Loadsol®) or conventional training using a bathroom scale (N = 12). After initial PWB training (20 kg) of one randomized leg, the immediate and one-week retention effects were analysed using mean and maximum load (N) and overload rate (%). Statistical analysis was performed using a two-way repeated measures ANOVA with post-hoc pairwise comparisons (p < 0.05). RESULTS: A significantly (p < 0.001) improved immediate and long-term PWB adherence was found for the insole feedback group during walking. A significant (p < 0.001) reduction of the overload rate by 86% was found for the insole feedback group when compared to the conventional training group after one week. Significant (p < 0.01) reductions by 51% and 46% was also found for the mean and maximum load in the insole feedback group when compared to the conventional training group. SIGNIFICANCE: The use of insole feedback systems can serve as a viable tool to become familiar with PWB and to provide optimal retention of specified loads. Therefore, such systems serve as an advantageous training intervention to maintain a prescribed PWB during locomotion.

Recovery of the medial gastrocnemius muscle after calcaneus fracture differs between contractile and elastic components.

BACKGROUND: Calcaneal fractures result in severe functional impairments and walking restrictions. Postoperative evaluation mainly focusses on the restoration of calcaneal anatomy while ankle plantar flexor insufficiency remains largely neglected. This study aims to investigate biomechanical and morphologic adaptions of elastic and contractile components of the gastrocnemius medialis after unilateral calcaneal fracture. METHODS: 20 Patients (BMI: 27.6 ± 3.1 kgm-2, Age: 50 ± 12 years) were measured using gait analysis and portable ultrasound over a follow-up of three, six and twelve months after surgery. Data comparison was performed using 20 matched healthy controls (BMI: 26.2 ± 2.9 kgm-2, Age: 48 ± 11 years). Static and dynamic behavior of the gastrocnemius muscle tendon unit, muscle fascicle and the serial-elastic element as well ankle joint kinematics and kinetics were analyzed. FINDINGS: Within patients, a significant (p < 0.05) increase in fascicle length (by 67%) during single support and a decrease of serial elastic element shortening (by 20%) during push off was found between three and twelve months follow-up comparisons. Patients showed differences for fascicle lengthening and pennation angle increase during single support after three and six months compared to healthy controls. A smaller shortening of the serial-elastic element (by 29%) and muscle-tendon unit (by 16%) persisted even for the twelve month comparisons. INTERPRETATION: Patients with calcaneal fracture showed an incomplete restoration of the medial gastrocnemius dynamic morphological behavior. While muscle fascicle contraction almost recovered, the serial elastic component still showed restrictions regarding its shortening behavior. Limited foot mobility and plantarflexor strength as well as lowered responsiveness of elastic tissues to mechanical loading are regarded as key mechanisms.

Reliability and validity varies among smartphone apps for range of motion measurements of the lower extremity: a systematic review.

The aim of this review was to determine whether smartphone applications are reliable and valid to measure range of motion (RoM) in lower extremity joints. A literature search was performed up to October 2020 in the databases PubMed and Cochrane Library. Studies that reported reliability or validity of smartphone applications for RoM measurements were included. The study quality was assessed with the QUADAS-2 tool and baseline information, validity and reliability were extracted. Twenty-five studies were included in the review. Eighteen studies examined knee RoM, whereof two apps were analysed as having good to excellent reliability and validity for knee flexion ("DrGoniometer", "Angle") and one app showed good results for knee extension ("DrGoniometer"). Eight studies analysed ankle RoM. One of these apps showed good intra-rater reliability and excellent validity for dorsiflexion RoM ("iHandy level"), another app showed excellent reliability and moderate validity for plantarflexion RoM ("Coach's Eye"). All other apps concerning lower extremity RoM had either insufficient results, lacked study quality or were no longer available. Some apps are reliable and valid to measure RoM in the knee and ankle joint. No app can be recommended for hip RoM measurement without restrictions.

Gait analysis - Available platforms for outcome assessment.

Movement or gait analysis has become a viable assessment tool not only used in sports science or basic biomechanical research, but has also expanded to be a very valuable instrument in clinical diagnostics, monitoring functional recovery and musculoskeletal rehabilitation. In this context, this method has long been an integral part solely in neurological disorders such as cerebral palsy. However, in the meantime the benefits have also become apparent in other medical areas, such as foot surgery, orthopaedic technology, or in patients after lower limb amputation. These procedures proved to better understand, objectify and quantify the individual causes of gait and movement disorders in order to optimize patient-specific therapy. Currently we are able to rely on a multitude of available measurement systems. These can either be used in everyday life for simple monitoring of one's own activity or to complement therapeutic approaches in the clinical and scientific environment. The following review highlights the various fields of movement analysis, including markerless motion capture, marker-based analysis, pedobarography and wearable sensors. Each of these areas presents its own field of application and potential usage as well as the advantages and disadvantages arising in this context. The following article will give an overview of the type of measurement technology used, the respective fields of application, and the selected parameters and their interpretation possibilities for each of the areas mentioned.

Upper Body Posture and Muscle Activation in Recreational Cyclists: Immediate Effects of Variable Cycling Setups.

Purpose: Discomfort during cycling can be counteracted by adjusting the seat position. However, the influence of changes in cycling position regarding quantitative biomechanical adaptions of the upper body in recreational cyclists is unclear. This study aims to investigate the effects of saddle position and reach distance on upper body kinematics and muscle activation. Methods: Twelve recreational cyclists were investigated in four different sitting positions on an adjustable cycle trainer. Trunk, pelvis, shoulder, elbow and spinal kinematics as well as lower back and elbow extensor activity were analyzed for combinations of normal and shortened reach distance including horizontal and 10° downward inclined saddle positions. Results: An inclined saddle increased activation of elbow extensors by almost 23 ± 8% (p < .01) while a shortened reach distance resulted in a more posterior pelvic tilt of up to 18 ± 2% (p < .01) and less trunk forward lean of 10 ± 9% (p < .01). Shoulder flexion reduced by up to 23 ± 16% (p < .05) while elbow flexion increased by 15 ± 22% (p < .05) with a shortened reach distance. No differences between configurations were found for spinal kinematics and lower back muscle activity. Conclusions: Changing the reach distance showed considerable biomechanical effects on upper body kinematics of the pelvis and trunk rather than on the spine or on lower back muscle activity. For reach distance, most compensation of postural changes of the upper body occurred by changes of shoulder and elbow angles while elbow extensor activation was only altered by saddle downward inclination.

Variability in trunk and pelvic movement of transfemoral amputees using a C-leg system compared to healthy controls.

OBJECTIVE: Gait variability is a measure of gait disturbance, and therefore constitutes a useful parameter for gait assessment as well as planning of therapeutic and medical interventions. To date, variability during walking has not been adequately analyzed in amputees. The aim of this examination was to evaluate trunk and pelvic movement variability in transfemoral amputees. The effect of different types of walking surfaces on variability in trunk and pelvic movement was also studied. METHOD: This prospective clinical examination compares 20 transfemoral amputees (17 ♂, 42 ±â€¯16 years; 3 ♀, 48 ±â€¯3 years) with a group of 20 age and mass matched healthy controls regarding the extent of variability in trunk and pelvic movement. Kinematic data of trunk and pelvic movement during walking on level, uneven ground and slope was captured by eight infrared cameras (Vicon Nexus ™, Oxford, UK). Variability in trunk and pelvic movement was analyzed. Univariate ANCOVA and ANOVA with repeated measures and post hoc tests were used for statistical comparison. Fall history was retrospectively collected from medical history to assess the association between falls and variability in trunk and pelvic movement. RESULTS: Trunk and pelvic movement variability in amputees was significantly higher during walking on uneven ground and slope compared to healthy controls (p ≤ 0.05). Variability in trunk and pelvic movement was increased during walking on uneven ground and slope compared to even ground for both groups (p ≤ 0.05). CONCLUSION: Amputees showed increased trunk and pelvic movement variability during walking on uneven ground and slope, indicating an affected gait pattern in comparison to healthy controls. Therefore, trunk and pelvic movement variability could be a potential marker for gait quality with diagnostic implications.

Gait characteristics and functional outcomes during early follow-up are comparable in patients with calcaneal fractures treated by either the sinus tarsi or the extended lateral approach.

BACKGROUND: To overcome the substantial functional loss after calcaneal fractures (CF), surgical treatment currently consists of two strategies, namely the commonly used extended lateral approach (ELA) and the less invasive sinus tarsi approach (STA). Despite the comparable anatomical restoration, the biomechanical and functional outcome of these strategies during early rehabilitation has not yet been investigated. RESEARCH QUESTION: To evaluate changes in gait characteristics and functional development in patients with CF treated by either STA or ELA. METHODS: A total of 56 patients with unilateral CF were included in this retrospective study. 26 patients were treated by ELA while 30 patients underwent surgery through the STA. Functional and biomechanical measurements were performed at follow-up periods of three and six months. Foot and ankle kinetics and kinematics were extracted using instrumented gait analysis with a multi segment foot model. Physical and mental components of the Short Form 36 (SF-36) and total scoring of the AOFAS hindfoot scale were used for functional evaluation. Statistical analysis was performed using Mann Whitney and Student's t-test. Effect sizes of group differences were calculated using Cohen's d. RESULTS: Comparisons between ELA and STA showed no significant difference regarding the biomechanical and functional outcome. Within-group comparisons showed significant (p < 0.05) improvements from three to six month follow-up. Ankle joint and hindfoot kinematics showed increased mobility during walking of up to 34% and 26%, respectively. Maximum ankle joint moment also improved by up to 34% while vertical ground reaction force increased by 8%. Functional outcome only revealed significant changes in the physical component of SF-36. SIGNIFICANCE: ELA and STA treatments revealed comparable functional improvements in patients with unilateral intraarticular calcaneal fractures during early rehabilitation. The less invasive STA provides adequate restoration of dynamic foot function and could serve as a viable alternative to the commonly used ELA.

Relation between the amount of daily activity and gait quality in transfemoral amputees.

Gait variability is often associated with reduced coordination and increased instability during walking. Especially for patients with musculoskeletal conditions, variability in gait might be associated with the level of daily activity. Therefore, this study examines kinematic variability during walking and the association with daily activity in patients with transfemoral amputation. Therefore, 15 transfemoral amputees, using the C-leg prosthesis of Otto Bock, between 18 and 65 years were recruited during their hospital stay. All patients were able to walk without crutches in everyday life and were familiar with walking using the C-leg system. Gait parameters and data of variability were captured during walking in a gait laboratory by eight infrared cameras (Vicon). Daily activity was assessed using a three-dimensional acceleration sensor of VitaMove. Patients showed variability from 0.84° up to 1.96° in frontal pelvis motion and from 0.9° up to 4.02° in trunk obliquity. The results show a significant correlation between activity and variability in trunk (r = -0.58; P ≤ 0.05) and pelvis (r = -0.63; P ≤ 0.01) as well as gait velocity (r = 0.6; P ≤ 0.05). However, kinematic variability and gait velocity are not related to each other. In conclusion, the results show that kinematic gait variability is associated with the extent of activity and therefore presents an important parameter for assessing amputees' gait quality and daily activity.

Effects of knee orthosis adjustment on biomechanical performance and clinical outcome in patients with medial knee osteoarthritis.

BACKGROUND: Valgus bracing in medial knee osteoarthritis aims to improve gait function by reducing the loading of the medial compartment. Orthosis composition and optimal adjustment is essential to achieve biomechanical and clinical effectiveness. OBJECTIVES: To investigate biomechanical functionality during gait, pain relief and compliance in patients with knee osteoarthritis using a lightweight adjustable knee unloader orthosis. STUDY DESIGN: Prospective observational clinical trial. METHODS: Instrumented gait analysis in 22 patients with unilateral medial knee osteoarthritis was performed after a 2-week orthosis acclimatisation period. Kinematics and kinetics during gait as well as force transmission from the orthosis to the knee were analysed. Measurements were performed without, at individualised and at reduced orthosis setting. The assessment was supplemented by patient-related pain sensation and compliance questionnaires. RESULTS: Orthosis wear significantly reduced the knee adduction moment by up to 20% depending on orthosis adjustment, whereas pain sensation was significantly reduced by 16%. A significant positive correlation was found between force transmissions and knee adduction moment as well as for frontal knee angle. Compliance was good with a main daily use of 2-6 h. CONCLUSION: The orthosis provides significant biomechanical improvements, pain relief and good patient compliance. Patients had a biomechanical benefit for the individualised and reduced orthosis adjustments. Clinical relevance In patients with medial knee osteoarthritis, a lightweight medial unloader orthosis effectively reduced external knee adduction moment and pain sensation during daily activities. Thus, use of lightweight orthoses effectively supports conservative treatment in medial knee osteoarthritis.

Triptan-induced disruption of trigemino-cortical connectivity.

OBJECTIVE: The 5-HT1B/D agonists (triptans) are specific headache medications that have no effect on pain as such. Although they are routinely used in the treatment of acute migraine attacks, the underlying mechanisms of action are still a matter of debate. METHODS: Forty-three healthy participants underwent fMRI while receiving trigemino-nociceptive stimulation and control stimuli in a standardized fMRI paradigm. Using a crossover, double-blind, placebo-controlled design, 21 participants (10 women, mean age 26.9, range 20-37 years) received sumatriptan and 22 participants (11 women, mean age 25.5, range 22-32 years) received acetylsalicylic acid (ASA). Administration of medication and saline was randomized between participants of each group resulting in half of the participants receiving saline and the other half receiving the respective medication during the first fMRI data acquisition. RESULTS: While mean pain intensity ratings did not differ significantly between control and medication nor between medications, we found a significant blood oxygen level-dependent signal increase in the trigeminal nuclei and the thalamus after sumatriptan treatment compared with placebo or ASA. In addition, we specifically looked for the pharmacologic modulation of functional coupling between trigeminal nuclei and higher brain areas, i.e., trigemino-cortical pathways, and found a strong coupling during the saline condition, which was altered by sumatriptan but not after ASA administration. CONCLUSION: These data suggest that a specific functional inhibition of trigemino-cortical projections is one of the reasons that triptans, unlike pain killers, act highly specifically on headache and migraine but not pain as such.