Novel classification of knee osteoarthritis severity based on spatiotemporal gait analysis

Can gait patterns be explained by joint structure in people with and without radiographic knee osteoarthritis? Data from the IMI-APPROACH cohort

OBJECTIVE

To determine the association between joint structure and gait in patients with knee osteoarthritis (OA).

METHODS

IMI-APPROACH recruited 297 clinical knee OA patients. Gait data was collected (GaitSmart®) and OA-related joint measures determined from knee radiographs (KIDA) and MRIs (qMRI/MOAKS). Patients were divided into those with/without radiographic OA (ROA). Principal component analyses (PCA) were performed on gait parameters; linear regression models were used to evaluate whether image-based structural and demographic parameters were associated with gait principal components.

RESULTS

Two hundred seventy-one patients (age median 68.0, BMI 27.0, 77% female) could be analyzed; 149 (55%) had ROA. PCA identified two components: upper leg (primarily walking speed, stride duration, hip range of motion [ROM], thigh ROM) and lower leg (calf ROM, knee ROM in swing and stance phases). Increased age, BMI, and radiographic subchondral bone density (sclerosis), decreased radiographic varus angle deviation, and female sex were statistically significantly associated with worse lower leg gait (i.e. reduced ROM) in patients without ROA (R2 = 0.24); in ROA patients, increased BMI, radiographic osteophytes, MRI meniscal extrusion and female sex showed significantly worse lower leg gait (R2 = 0.18). Higher BMI was significantly associated with reduced upper leg function for non-ROA patients (R2 = 0.05); ROA patients with male sex, higher BMI and less MRI synovitis showed significantly worse upper leg gait (R2 = 0.12).

CONCLUSION

Structural OA pathology was significantly associated with gait in patients with clinical knee OA, though BMI may be more important. While associations were not strong, these results provide a significant association between OA symptoms (gait) and joint structure.

Gait classification of knee osteoarthritis patients using shoe-embedded internal measurement units sensor

BACKGROUND

Knee osteoarthritis negatively affects the gait of patients, especially that of elderly people. However, the assessment of wearable sensors in knee osteoarthritis patients has been under-researched. During clinical assessments, patients may change their gait patterns under the placebo effect, whereas wearable sensors can be used in any environment.

METHODS

Sixty patients with knee osteoarthritis and 20 control subjects were included in the study. Wearing shoes with an IMU sensor embedded in the insoles, the participants were required to walk along a walkway. The sensor data were collected during the gait. To discriminate between healthy and knee osteoarthritis patients and to classify different subgroups of knee osteoarthritis patients (patients scheduled for surgery vs. patients not scheduled for surgery; bilateral knee osteoarthritis diagnosis vs. unilateral knee osteoarthritis diagnosis), we used a machine learning approach called the support vector machine. A total of 88 features were extracted and used for classification.

FINDINGS

The patients vs. healthy participants were classified with 71% accuracy, 85% sensitivity, and 56% specificity. The "patients scheduled for surgery" vs. "patients not scheduled for surgery" were classified with 83% accuracy, 83% sensitivity, and 81% specificity. The bilateral knee osteoarthritis diagnosis vs. unilateral knee osteoarthritis diagnosis was classified with 81% accuracy, 75% sensitivity, and 79% specificity.

INTERPRETATION

Gait analysis using wearable sensors and machine learning can discriminate between healthy and knee osteoarthritis patients and classify different subgroups with reasonable accuracy, sensitivity, and specificity. The proposed approach requires no complex gait factors and is not limited to controlled laboratory settings.

Maximal daily stepping cadence partially explains functional capacity of individuals with end-stage knee osteoarthritis

BACKGROUND

Individuals with end-stage knee osteoarthritis (OA) walk at a lower intensity (ie, slower step cadence) contributing to worse physical function. Previous literature reports daily step counts and sedentary time, with little information regarding stepping bouts or cadence. Determining relationships between daily higher stepping cadence duration and clinical outcomes can move the field toward optimal daily stepping prescription.

OBJECTIVE

To quantify daily physical activity patterns of individuals with end-stage knee OA and determine the contribution of high stepping cadence to explain functional capacity variability.

DESIGN

Cross-sectional analysis.

SETTING

Veterans Administration medical center.

PARTICIPANTS

U.S. military veterans (n = 104; age: 67.1 years [7.2]; mean [SD]; male [89.3%]) with end-stage knee OA were enrolled.

INTERVENTION

Not applicable.

MAIN OUTCOME MEASURE

Functional capacity (6-Minute Walk Test [6MWT]). Physical activity (activPAL wearable sensor; cadence and time sitting, standing, and stepping), pain (Western Ontario and McMaster Universities Osteoarthritis Index-pain subscale) sociodemographic variables, and comorbidities (body mass index and Functional Comorbidity Index) are the main explanatory variables.

RESULTS

Participants' wake time was mainly sitting (11.0 h/day) in ≥60-minute bouts (29.7% ± 12.7 of sitting time). Standing (3.4 hours/day) and stepping (1.4 h/day) primarily occurred in 0-5 minute bouts (standing: 87.7% ± 14.4 of standing time, stepping: 98.7% ± 12.7 of stepping time) and stepping cadence was predominantly incidental (1-19 spm; 52.9% ± 9.6 of total stepping time). Backward elimination model results indicated shorter medium-to-brisk cadence bout duration, older age, and higher pain significantly explained shorter 6MWT distance (AdjR2=0.24, p < .01).

CONCLUSIONS

Individuals with knee OA spend most of their waking hours sitting, while standing and stepping occurs in short bouts at very low stepping cadence. Decreased time in high stepping cadence is associated with lower functional capacity. Future studies should explore if increasing the daily time spent in higher step cadence can improve functional capacity in this population.

Gait kinematics of osteoarthritic knees after intra-articular viscosupplementation: A double-blinded randomized controlled trial

BACKGROUND

The utilization of subjective questionnaires for assessing conservative treatment in knee osteoarthritis may present challenges in identifying differences due to inadequate statistical power. Objective tools, such as three-dimensional (3D) kinematic analysis, are accurate and reproducible methods. However, no high-quality studies assessing the effects of intra-articular viscosupplementation (VS) have been published. Therefore, the objective of the study was to evaluate gait kinematics of patients with advanced knee osteoarthritis after VS.

METHODS

Forty-two patients were randomized to receive either VS or saline injection (placebo). They underwent 3D kinematic gait analysis before and at 1, 6, and 12 weeks after treatment and knee angles during stance phase were determined. Patients and the healthcare team responsible for data collection, processing, and analysis were blinded to group allocation. Between-group comparisons were conducted using linear mixed models.

RESULTS

Compared with placebo, the VS increased the maximum knee extension (3.2° (0.7-5.7)) and decreased the maximum knee flexion (-3.6° (-6.1 to -1.2)) on the sagittal plane at 1 week. At 6 weeks, the VS group sustained a reduced maximum knee flexion (-2.6° (-5.2 to 0.0)). On the axial plane, the VS group demonstrated an increase in maximum internal rotation at 12 weeks (3.9° (0.3 to 7.7)). The VS group exhibited reduced single-leg stance time at 1 week and increased total stance time at 12 weeks.

CONCLUSIONS

VS led to short- and long-term kinematic improvements in the sagittal and axial planes, leading to a gait pattern closer to that observed in individuals with less severe osteoarthritic knees.

Classification of inertial sensor-based gait patterns of orthopaedic conditions using machine learning: A pilot study

Elderly patients often have more than one disease that affects walking behavior. An objective tool to identify which disease is the main cause of functional limitations may aid clinical decision making. Therefore, we investigated whether gait patterns could be used to identify degenerative diseases using machine learning. Data were extracted from a clinical database that included sagittal joint angles and spatiotemporal parameters measured using seven inertial sensors, and anthropometric data of patients with unilateral knee or hip osteoarthritis, lumbar or cervical spinal stenosis, and healthy controls. Various classification models were explored using the MATLAB Classification Learner app, and the optimizable Support Vector Machine was chosen as the best performing model. The accuracy of discrimination between healthy and pathologic gait was 82.3%, indicating that it is possible to distinguish pathological from healthy gait. The accuracy of discrimination between the different degenerative diseases was 51.4%, indicating the similarities in gait patterns between diseases need to be further explored. Overall, the differences between pathologic and healthy gait are distinct enough to classify using a classical machine learning model; however, routinely recorded gait characteristics and anthropometric data are not sufficient for successful discrimination of the degenerative diseases.

Inertial Sensor Location for Ground Reaction Force and Gait Event Detection Using Reservoir Computing in Gait

Inertial measurement units (IMUs) have shown promising outcomes for estimating gait event detection (GED) and ground reaction force (GRF). This study aims to determine the best sensor location for GED and GRF prediction in gait using data from IMUs for healthy and medial knee osteoarthritis (MKOA) individuals. In this study, 27 healthy and 18 MKOA individuals participated. Participants walked at different speeds on an instrumented treadmill. Five synchronized IMUs (Physilog®, 200 Hz) were placed on the lower limb (top of the shoe, heel, above medial malleolus, middle and front of tibia, and on medial of shank close to knee joint). To predict GRF and GED, an artificial neural network known as reservoir computing was trained using combinations of acceleration signals retrieved from each IMU. For GRF prediction, the best sensor location was top of the shoe for 72.2% and 41.7% of individuals in the healthy and MKOA populations, respectively, based on the minimum value of the mean absolute error (MAE). For GED, the minimum MAE value for both groups was for middle and front of tibia, then top of the shoe. This study demonstrates that top of the shoe is the best sensor location for GED and GRF prediction.

Gait biomechanics phenotypes among total knee arthroplasty candidates by machine learning cluster analysis

Knee osteoarthritis patient phenotyping is relevant to developing targeted treatments and assessing the treatment efficacy of total knee arthroplasty (TKA). This study aimed to identify clusters among TKA candidates based on demographic and knee mechanic features during gait, and compare gait changes between clusters postoperatively. TKA patients underwent 3D gait analysis 1-week pre (n = 134) and 1-year post-TKA (n = 105). Principal component analysis was applied to frontal and sagittal knee angle and moment waveforms, extracting major patterns of variability. Age, sex, body mass index, gait speed, and frontal and sagittal pre-TKA angle and moment PC scores previously identified as relevant to TKA outcomes were standardized (mean = 0, SD = 1, [134 × 15]). Multidimensional scaling and machine learning-based hierarchical clustering were applied. Final clusters were validated by examining intercluster differences pre-TKA and gait feature changes (Post_PCscore  - Pre_PCscore ) by k-way Χ² and ANOVA tests. Four TKA candidate phenotypes yielded optimum clustering metrics, interpreted as higher and lower functioning clusters that were predominantly male and female. Higher functioning clusters pre-TKA (clusters 1 and 4) had more dynamic sagittal flexion moment (p < 0.001) and frontal plane adduction moment (p < 0.001) loading/un-loading patterns during stance. Post-TKA, higher functioning clusters demonstrated less knee mechanic improvements during gait (flexion angle p < 0.001; flexion moment p < 0.001). TKA candidates can be characterized by four clusters, predominately separated by sex and knee joint biomechanics. Post-TKA knee kinematics and kinetics improvements were cluster-specific; lower functioning clusters experienced more improvement. Cluster-based patient profiling may aid in triaging and developing OA management and surgical strategies meeting group-level function needs.

Gait subgroups among older adults with chronic pain differ in cerebellum and basal ganglia gray matter volumes

BACKGROUND

Current literature regarding morphological gray matter atrophy in chronic pain is mixed, inhibiting our ability to understand neurological mechanisms of chronic pain. The inconsistent findings may be due to the presence of subgroups within the older adult chronic pain population that differ in gait performance, as gait and gray matter have been previously associated. These gait subgroups, however, have been inadequately characterized in prior work and have not been compared across gray matter measures. Therefore, the purpose of this study was to identify and characterize gait subgroups within the older adult chronic pain population, and to evaluate differences in gray matter measures between subgroups.

METHODS

The present study was a secondary analysis of the Neuromodulatory Examination of Pain and Mobility Across the Lifespan (NEPAL) study. A subset of older participants (n = 40) completed assessments to evaluate psychological status, cognitive abilities, pain characteristics, and spatiotemporal gait performance using an instrumented gait mat. Gray matter measures were obtained from a T1-weighted anatomical scan using Freesurfer's recon-all function.

RESULTS

After data reduction, a hierarchical cluster analysis identified three gait clusters: A Normal Gait cluster (n = 12), a Shuffle Gait cluster (n = 15), and an Unsteady Gait cluster (n = 13). Clusters differed in gait velocity, stride length, step width, double support percentages, and stride length variability. The Shuffle Gait cluster exhibited reduced gray matter volumes in the cerebellum, caudate, putamen, and pallidum, as well as a worse pain severity when compared to the Normal Gait cluster (p < 0.05). The Shuffle Gait cluster also had less gray matter in the cerebellum and caudate when compared to the Unsteady Gait cluster (p < 0.05).

CONCLUSIONS

Our results confirm the existence of gait subgroups among the older adult chronic pain population and gray matter differences observed between groups support the need for the consideration of subgroups within this population for future pain, mobility, and aging studies.

Smartphone-based inertial sensors technology - Validation of a new application to measure spatiotemporal gait metrics

BACKGROUND

Smartphones are increasingly recognized as the future technology for clinical gait assessment.

RESEARCH QUESTION

To determine the concurrent validity of gait parameters obtained using the smartphone technology and application in a group of patients with musculoskeletal pathologies.

METHODS

Patients with knee, lower back, hip, or ankle pain were included in the study (n = 72). Spatiotemporal outcomes were derived from the walkway and the smartphone simultaneously. Pearson's correlations and limits of agreement (LoA) determined the association between the two methods.

RESULTS

Cadence and gait cycle time showed excellent correlation and agreement between the smartphone and the walkway (cadence: r = 0.997, LoA=1.4%, gait cycle time: r = 0.996, LoA = 1.6%). Gait speed, double-limb support and left and right step length demonstrated strong correlations and moderate agreement between methods (gait speed: r = 0.914, LoA=15.4%, left step length: r = 0.842, LoA = 17.0%, right step length: r = 0.800, LoA=16.4%). The left and right measures of single-limb support and stance percent showed a consistent 4% bias across instruments, yielding moderate correlation and very good agreement between the smartphone and the walkway (r = 0.532, LoA = 9% and r = 0.460, LoA=9.8% for left and right single-limb support; r = 0.463, LoA = 5.1% and r = 0.533, LoA = 4.4% for left and right stance).

SIGNIFICANCE

The examined application appears to be a valid tool for gait analysis, providing clinically significant metrics for the assessment of patients with musculoskeletal pathologies. However, additional studies should examine the technology amongst patients with severe gait abnormalities.

Assessment of spatiotemporal gait parameters using a deep learning algorithm-based markerless motion capture system

Spatiotemporal parameters can characterize the gait patterns of individuals, allowing assessment of their health status and detection of clinically meaningful changes in their gait. Video-based markerless motion capture is a user-friendly, inexpensive, and widely applicable technology that could reduce the barriers to measuring spatiotemporal gait parameters in clinical and more diverse settings. Two studies were performed to determine whether gait parameters measured using markerless motion capture demonstrate concurrent validity with those measured using marker-based motion capture and a pressure-sensitive gait mat. For the first study, thirty healthy young adults performed treadmill gait at self-selected speeds while marker-based motion capture and synchronized video data were recorded simultaneously. For the second study, twenty-five healthy young adults performed over-ground gait at self-selected speeds while footfalls were recorded using a gait mat and synchronized video data were recorded simultaneously. Kinematic heel-strike and toe-off gait events were used to identify the same gait cycles between systems. Nine spatiotemporal gait parameters were measured by each system and directly compared between systems. Measurements were compared using Bland-Altman methods, mean differences, Pearson correlation coefficients, and intraclass correlation coefficients. The results indicate that markerless measurements of spatiotemporal gait parameters have good to excellent agreement with marker-based motion capture and gait mat systems, except for stance time and double limb support time relative to both systems and stride width relative to the gait mat. These findings indicate that markerless motion capture can adequately measure spatiotemporal gait parameters of healthy young adults during treadmill and over-ground gait.

Novel Method of Classification in Knee Osteoarthritis: Machine Learning Application Versus Logistic Regression Model

Objective

To present new classification methods of knee osteoarthritis (KOA) using machine learning and compare its performance with conventional statistical methods as classification techniques using machine learning have recently been developed.

Methods

A total of 84 KOA patients and 97 normal participants were recruited. KOA patients were clustered into three groups according to the Kellgren-Lawrence (K-L) grading system. All subjects completed gait trials under the same experimental conditions. Machine learning-based classification using the support vector machine (SVM) classifier was performed to classify KOA patients and the severity of KOA. Logistic regression analysis was also performed to compare the results in classifying KOA patients with machine learning method.

Results

In the classification between KOA patients and normal subjects, the accuracy of classification was higher in machine learning method than in logistic regression analysis. In the classification of KOA severity, accuracy was enhanced through the feature selection process in the machine learning method. The most significant gait feature for classification was flexion and extension of the knee in the swing phase in the machine learning method.

Conclusion

The machine learning method is thought to be a new approach to complement conventional logistic regression analysis in the classification of KOA patients. It can be clinically used for diagnosis and gait correction of KOA patients.

Wearable Inertial Sensors for Gait Analysis in Adults with Osteoarthritis-A Scoping Review

Our objective was to conduct a scoping review which summarizes the growing body of literature using wearable inertial sensors for gait analysis in lower limb osteoarthritis. We searched six databases using predetermined search terms which highlighted the broad areas of inertial sensors, gait, and osteoarthritis. Two authors independently conducted title and abstract reviews, followed by two authors independently completing full-text screenings. Study quality was also assessed by two independent raters and data were extracted by one reviewer in areas such as study design, osteoarthritis sample, protocols, and inertial sensor outcomes. A total of 72 articles were included, which studied the gait of 2159 adults with osteoarthritis (OA) using inertial sensors. The most common location of OA studied was the knee (n = 46), followed by the hip (n = 22), and the ankle (n = 7). The back (n = 41) and the shank (n = 40) were the most common placements for inertial sensors. The three most prevalent biomechanical outcomes studied were: mean spatiotemporal parameters (n = 45), segment or joint angles (n = 33), and linear acceleration magnitudes (n = 22). Our findings demonstrate exceptional growth in this field in the last 5 years. Nevertheless, there remains a need for more longitudinal study designs, patient-specific models, free-living assessments, and a push for "Code Reuse" to maximize the unique capabilities of these devices and ultimately improve how we diagnose and treat this debilitating disease.

Gait acquisition and analysis system for osteoarthritis based on hybrid prediction model

Osteoarthritis (OA) is the most common type of joint-related diseases, which affects millions of people worldwide. Expensive and time-consuming medical imaging can provide precise structural description of knee joints, but lacks the functional descriptions. Gait analysis can provide functional descriptions of knee joints. However, orthopedic surgeons always observe the patient's gait qualitatively and perform subjective assessments through rating scales at present due to the lack of a quantitative gait analysis system. To solve these problems, a gait acquisition and analysis system is developed to provide a cheap, easy-to-use solution for quantitative recording and functional description of OA patients. Firstly, an automatic gait acquisition platform is designed for the clinical setting based on the RGB-D camera and the developed software of gait data recording. In addition, the effective working space of gait acquisition platform is evaluated for clinical applications by comparing with the ground-truth from infrared optical trackers. Secondly, the acquired gait data is analyzed with a novel hybrid prediction model to assess the gait anomalies quantitatively and objectively. In the hybrid model, the extracted features of gait data contain the manually-extracted features and the automatically-extracted features from Long Short-Term Memory network. Experimental results on real patients demonstrate that the proposed gait analysis system can quantitatively predict gait anomalies with a high accuracy of 98.77 %. Therefore, this gait acquisition and analysis system achieves quantitative recording and objective assessment of gait anomalies for clinical OA treatments.

Discriminant validity and reproducibility of spatiotemporal and kinetic parameters during treadmill walking in patients with knee osteoarthritis

BACKGROUND

Instrumented treadmills are potentially useful tools for the assessment of gait parameters in orthopaedic clinical settings, but their measurement properties remain uncertain.

RESEARCH QUESTION

What is the discriminant validity and reproducibility of spatiotemporal and kinetic gait parameters measured by a pressure-instrumented treadmill at different speeds and inclinations in patients with knee osteoarthritis (KOA)?

METHODS

A total of 54 patients with unilateral KOA and 23 healthy controls took part in the study. Step length, single-limb support duration and ground reaction force were recorded during level and uphill walking at 3 and 4 km/h using a commercially-available treadmill instrumented with an integrated pressure platform. We examined discriminant validity (difference between involved and uninvolved side as well as against healthy controls) and test-retest reproducibility (reliability and agreement).

RESULTS

Significant side differences were observed for single-limb support duration and ground reaction force at touchdown in all conditions (P < 0.05). All the investigated gait parameters showed acceptable reliability and agreement, except step length at 4 km/h uphill.

SIGNIFICANCE

We conclude that the pressure-instrumented treadmill used in this study may have good clinical utility for quantitative gait analysis in patients with KOA under different experimental conditions.

Gait features for discriminating between mobility-limiting musculoskeletal disorders: Lumbar spinal stenosis and knee osteoarthritis

BACKGROUND

Functional ambulation limitations are features of lumbar spinal stenosis (LSS) and knee osteoarthritis (OA). With numerous validated walking assessment protocols and a vast number of spatiotemporal gait parameters available from sensor-based assessment, there is a critical need for selection of appropriate test protocols and variables for research and clinical applications.

RESEARCH QUESTION

In patients with knee OA and LSS, what are the best sensor-derived gait parameters and the most suitable clinical walking test to discriminate between these patient populations and controls?

METHODS

We collected foot-mounted inertial measurement unit (IMU) data during three walking tests (fast-paced walk test-FPWT, 6-min walk test- 6MWT, self-paced walk test - SPWT) for subjects with LSS, knee OA and matched controls (N = 10 for each group). Spatiotemporal gait characteristics were extracted and pairwise compared (Omega partial squared - ω_p²) between patients and controls.

RESULTS

We found that normal paced walking tests (6MWT, SPWT) are better suited for distinguishing gait characteristics between patients and controls. Among the sensor-based gait parameters, stance and double support phase timing were identified as the best gait characteristics for the OA population discrimination, whereas foot flat ratio, gait speed, stride length and cadence were identified as the best gait characteristics for the LSS population discrimination.

SIGNIFICANCE

These findings provide guidance on the selection of sensor-derived gait parameters and clinical walking tests to detect alterations in mobility for people with LSS and knee OA.

The effect of treatment with a non-invasive foot worn biomechanical device on subjective and objective measures in patients with knee osteoarthritis- a retrospective analysis on a UK population

Background

Osteoarthritis is a major cause of pain and disability worldwide, therefore ways of treating this condition are paramount to a successful health system. The purpose of the study was to investigate the changes in spatial-temporal gait parameters and clinical measurements following treatment with a non-invasive foot-worn biomechanical device on patients with knee osteoarthritis within the UK.

Methods

A retrospective analysis was carried out on 455 patients with knee osteoarthritis. All patients were evaluated using a computerized gait test and two self-assessment questionnaires (WOMAC and SF-36) at baseline and after 3 and 6 months of treatment. The biomechanical device is a shoe-like device with convex pods under the sole that have the capability of changing foot centre of pressure and training neuromuscular control. The device was individually calibrated for each patient to minimise symptoms whilst walking and train neuromuscular control. Patients used the device for short periods during activities of daily living. Repeated measures statistical analyses were performed to compare differences over time.

Results

After 6 months of treatment significant improvements were seen in all gait parameters (p < 0.01). Specifically, gait velocity, step length and single limb support of the more symptomatic knee improved by 13, 7.8 and 3%, respectively. These were supported by significant improvements in pain, function and quality of life (48.6, 45.7 and 22% respectively; p < 0.001). A sub-group analysis revealed no baseline differences between those who were recommended joint replacement and those who were not. Both groups improved significantly over time (p < 0.05 for all).

Conclusions

Our results suggest that the personalised biomechanical treatment can improve gait patterns, pain, function and quality of life. It may provide an additional solution to managing UK patients suffering from knee osteoarthritis but needs to be tested in a controlled setting first.

Injection route affects intra-articular hyaluronic acid distribution and clinical outcome in viscosupplementation treatment for knee osteoarthritis: a combined cadaver study and randomized clinical trial

The coverage of hyaluronic acid (HA) on the impaired cartilage should be the precondition to exert its beneficial effect on knee osteoarthritis (KOA) according to the pharmacological mechanism. However, the intra-articular distribution of HA might be correlated with the route of drug delivery. Forty-two cadaver knees with radiographic evidence of osteoarthritis were given anteromedial (AM) or medial midpatellar (MMP) injection of HA (molecular weight 600-1500 kD) followed by gait stimulation. Although 2.5 ml HA delivered through both routes failed to cover the entire cartilage, HA covered 96.12% cartilage of patellofemoral joint (PFJ) and 71.44% of medial femorotibial joint (FTJ) through MMP route, whereas mainly distributed into FTJ and posterior condyles through AM route. HA in the MMP group distributed more in PFJ than that in the AM group (P < 0.001), but no significant difference presented in medial FTJ (P = 0.084). The clinical efficacy was also associated with the route of drug delivery. One hundred patients with unilateral mild-to-moderate KOA were recruited and randomly assigned to receive five weekly HA injections with AM route (n = 50) or MMP route (n = 50). Patients in the MMP group obtained better improvement in WOMAC index total score, pain score, stiffness score, and Lequesne index total score over the entire follow-up period, as compared to patients in the AM group (all P < 0.01). More patients in the MMP group claimed pain relief (71.7%, P = 0.024) and felt satisfying (63.1%, P = 0.007) than in the AM group at the end of follow-up. Therefore, intra-articular HA injection through MMP route is recommended in treating mild-to-moderate KOA. Graphical Abstract .

Identification of knee osteoarthritis disability phenotypes regarding activity limitation: a cluster analysis

Background

Studies have reported the subtypes of individuals with knee osteoarthritis (OA) attempting to cluster this heterogonous condition. Activity limitations are commonly used to set goals in knee OA management and better identify subgroups based on level of disability in this patient population. Therefore, the objective of this study was to identify those activity limitations which could classify the disability phenotypes of knee OA. The phenotypes were also validated by comparing impairments and participation restrictions.

Methods

Participants comprised individuals with symptomatic knee OA. They were interviewed and undertook physical examination according to a standard evaluation forms based on the International Classification of Functioning, Disability and Health (ICF) model. Cluster analysis was used to determine those activity limitations which could best classify the phenotypes of knee OA. To validate the clustered variables, comparisons and regression analysis were performed for the impairments consisting of pain intensity, passive range of motion and muscle strength, and the participation restrictions included the difficulty level of acquiring goods and services and community life.

Results

In all, 250 participants with symptomatic knee OA were enrolled in the study. Three activity limitations identified from data distribution and literature were used as the cluster variables, included the difficulty level of maintaining a standing position, timed stair climbing and 40-m self-paced walk test. The analysis showed four phenotypes of individuals with knee OA according to the levels of disability from no to severe level of disability. All parameters of impairment and participation restrictions significantly differed among phenotypes. Subgroups with greater disability experienced worse pain intensity, limited range of motion (ROM), muscle power and participation restriction levels. The variance accounted for of the subgroups were also greater than overall participants.

Conclusion

The results of this study emphasized the heterogeneous natures of knee OA. Three activity limitations identified could classify the individuals with symptomatic knee OA to homogeneous subgroups from no to severe level of disability. The management plan, based on these homogeneous subgroups of knee OA, could be designated by considering the levels of impairments and participation restrictions.

Chinese primary knee osteoarthritis progression cohort (CPKOPC) to evaluate the progression of knee osteoarthritis in the Beijing population: a prospective cohort study protocol

INTRODUCTION

Millions of patients are currently suffering from pain and dysfunction caused by osteoarthritis (OA), and billions of dollars have been invested into treatment. Because there is no effective treatment that can reverse the progression of knee OA, it is important to determine the risk factors that may influence the progression. However, although there are many studies that examine risk factors for progression, there are only a few that specifically focus on the impact of each risk factor for predicting progression of knee OA. This study aimed to develop a cohort of patients with primary knee OA in the Beijing area to establish models that identify the influence of each risk factor on the prediction of knee OA progression.

METHODS AND ANALYSIS

This is a prospective, multicentre, hospital-based cohort study. The study population comprises 2000 patients with primary knee OA from the Beijing area. The recruitment and baseline visits started in December 2017 and will finish in November 2018. After baseline visits, the patients will be followed for 3 years or until the occurrence of primary outcomes. Demographic variables will be collected during the baseline visit. Influencing factors including occupational exposures, family history and treatment will be collected at baseline and each follow-up visit. The primary outcome measure is a comprehensive index which will be combined with clinical WOMAC score, imaging K-L grade and clinical outcomes. These data will also be collected at baseline and each follow-up visit.

ETHICS AND DISSEMINATION

This study protocol has been approved by Peking University Third Hospital Medical Science Research Ethics Committee. All the eligible participants will give written informed consent. The findings will be published in peer-reviewed journals and presented at national or international conferences. Besides, the results will be disseminated to all participants via the social software 'WeChat'.

TRIAL REGISTRATION NUMBER

ChiCTR-ROC-17013790; preresults.

Knee Joint Biomechanical Gait Data Classification for Knee Pathology Assessment: A Literature Review

Background

The purpose of this study is to review the current literature on knee joint biomechanical gait data analysis for knee pathology classification. The review is prefaced by a presentation of the prerequisite knee joint biomechanics background and a description of biomechanical gait pattern recognition as a diagnostic tool. It is postfaced by discussions that highlight the current research findings and future directions.

Methods

The review is based on a literature search in PubMed, IEEE Xplore, Science Direct, and Google Scholar on April 2019. Inclusion criteria admitted articles, written in either English or French, on knee joint biomechanical gait data classification in general. We recorded the relevant information pertaining to the investigated knee joint pathologies, the participants' attributes, data acquisition, feature extraction, and selection used to represent the data, as well as the classification algorithms and validation of the results.

Results

Thirty-one studies met the inclusion criteria for review.

Conclusions

The review reveals that the importance of medical applications of knee joint biomechanical gait data classification and recent progress in data acquisition technology are fostering intense interest in the subject and giving a strong impetus to research. The review also reveals that biomechanical data during locomotion carry essential information on knee joint conditions to infer an early diagnosis. This survey paper can serve as a useful informative reference for research on the subject.

Correlation between preoperative imaging parameters and postoperative basic kinematics-based functional outcome in patients with tibial plateau fractures

BACKGROUND

Functional scores and radiographs are often used to assess function and predict development of osteoarthritis in patients with multi-fragmentary tibial plateau fractures (TPFs). Locomotion, which is the primary goal of fracture treatment, is rarely assessed. The objective of this study was to assess functional ability of patients after TPF fixation using spatio-temporal gait analysis (STGA), and to compare STGA variables with self-reported functional scores and preoperative fracture characteristics.

METHODS

Preoperative CT scans of 21 patients with complete articular multi-fragmentary TPFs were evaluated for number of fragments, maximum gap between the fragments and maximum articular depression. All patients underwent STGA (velocity, cadence, step length of the affected and the unaffected leg, single-limb support by the affected and the unaffected leg, and double-leg support) and filled the Knee Society Score and the Short Form-12 questionnaires on average 3 years (SD = 1.56, range, 2-5.8) post-injury.

FINDINGS

Step length and single-limb support time of the affected leg were shorter compared to the unaffected leg (p = 0.02 and p = 0.007, respectively). Number of fracture fragments correlated with cadence (R = -0.461, p = 0.04) and velocity (R = -0.447, p = 0.04).

INTERPRETATION

Given that both higher fracture comminution and deformity on the one hand and the above gait parameter alterations on the other hand are associated with knee osteoarthritis, STGA may be used for routine postoperative evaluation of patients after TPF fixation.

Exploring the clinical context of adopting an instrumented insole: a qualitative study of clinicians' preferences in England

OBJECTIVES

This study explores clinicians' views of the clinical uptake of a smart pressure-sensing insole, named Flexifoot, to enhance the care and management of patients with osteoarthritis (OA). Clinicians are key users of wearable technologies, and can provide appropriate feedback for a specific device for successful clinical implementation.

DESIGN

Qualitative study with in-depth, semi-structured interviews, analysed using inductive analysis to generate key themes.

SETTING

Conducted in a University setting.

PARTICIPANTS

30 clinicians were interviewed (11 physiotherapists, 11 orthopaedic surgeons, 5 general practitioners, 3 podiatrists).

RESULTS

All clinicians regarded Flexifoot to be useful for the care and management of patients in adjunction to current methods. Responses revealed four main themes: use, data presentation, barriers to use and future development. Flexifoot data were recognised as capable of enhancing information exchange between clinicians and patients, and also between clinicians themselves. Participants supported the use of feedback for rehabilitation, screening and evaluation of treatment progress/success purposes. Flexifoot use by patients was encouraged as a self-management tool that may motivate them by setting attainment goals. The data interface should be secure, concise and visually appealing. The measured parameters of Flexifoot, its duration of wear and frequency of data output would all depend on the rationale for its use. The clinicians and patients must collaborate to optimise the use of Flexifoot for long-term monitoring of disease for patient care in clinical practice. Many identified potential other uses for Flexifoot.

CONCLUSIONS

Clinicians thought that Flexifoot may complement and improve current methods of long-term patient management for OA or other conditions in clinical settings. Flexifoot was recognised to be useful for objective measures and should be tailored carefully for each person and condition to maximise compliance. Adopting the device, and other similar technologies, requires reducing the main barriers to use (time, cost, patient compliance) before its successful implementation.

Blueberries Improve Pain, Gait Performance, and Inflammation in Individuals with Symptomatic Knee Osteoarthritis

Osteoarthritis (OA) is the most common joint disorder in the world and is the most frequent cause of walking related disability among older adults in the US, which brings a significant economic burden and reduces quality of life. The initiation and development of OA typically involves degeneration or progressive loss of the structure and function of articular cartilage. Inflammation is one of the major drives of the progression of OA. Dietary polyphenols have been studied for their anti-inflammatory properties and potential anabolic effects on the cartilage cells. Blueberries are widely consumed and are high in dietary polyphenols, therefore regular consumption of blueberries may help improve OA. The purpose of the present study was to examine the effect of freeze dried whole blueberries on pain, gait performance, and inflammation in individuals with symptomatic knee OA. In a randomized, double-blind trial, adults age 45 to 79 with symptomatic knee OA, were randomized to either consume 40 g freeze-dried blueberry powder (n = 33) or placebo powder (n = 30) daily for four months. Blood draws and assessment of pain and gait were conducted at baseline, two months, and four months. Western Ontario McMaster Osteoarthritis Index (WOMAC) questionnaires were used to assess pain and GAITRite^® electronic walkway was used to evaluate gait spatiotemporal parameters. WOMAC total score and sub-groups, including pain, stiffness, and difficulty to perform daily activities decreased significantly in the blueberry treatment group (p < 0.05), but improvement of WOMAC total score and difficulty to perform daily activities were not observed in the placebo group. Normal walking pace single support percentage for both limbs increased (p = or < 0.007), while double support percentage for both limbs decreased in the blueberry treatment group (p = or < 0.003). No significant changes were observed in plasma concentrations of tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-6, IL-10, IL-13, matrix metalloproteinases (MMP)-3, MMP-13, and monocyte chemoattractant protein-1 (MCP-1) in both treatment groups. However, an increasing trend for IL-13 concentration and a decreasing trend in MCP-1 concentration were noted in the blueberry group. The findings of this study suggest that daily incorporation of whole blueberries may reduce pain, stiffness, and difficulty to perform daily activities, while improving gait performance, and would therefore improve quality of life in individuals with symptomatic knee OA.

Knee motion and muscle activation patterns are altered in hip osteoarthritis: The effect of severity on walking mechanics

BACKGROUND

Knee function is impaired in individuals with moderate hip osteoarthritis. How this extends to those undergoing total hip arthroplasty is unknown despite the common requirement for knee arthroplasty in this population. The study purpose was to determine whether sagittal plane knee joint movements and quadriceps and hamstring activation patterns differ between individuals with either moderate or severe unilateral hip osteoarthritis, and between ipsilateral and contralateral knees.

METHODS

20 individuals with moderate osteoarthritis and 20 with severe osteoarthritis were recruited. Sagittal knee motion and surface electromyograms from the hamstrings and quadriceps were collected during treadmill walking at a self-selected speed. Principal component analysis captured amplitude and temporal sagittal plane motion and EMG waveform features. Student's t-tests and Analysis of Variance determined between group differences and within/between group leg differences.

FINDINGS

The severe groups' contralateral knee was in greater flexion at initial contact and demonstrated a movement profile of a longer stance phase (p < 0.001). The severe group had reduced sagittal plane knee motion (p < 0.0001); more so in the ipsilateral knee (p < 0.0001). The severe group had greater hamstring (p = 0.009) and quadriceps activation (p < 0.001) overall, specifically mid-stance quadriceps bilaterally (p = 0.002). Ipsilateral sagittal plane knee motion was reduced in both groups. Compared with those with moderate osteoarthritis, individuals with severe osteoarthritis walk with reduced sagittal plane knee motion bilaterally, suggesting prolonged contralateral stance, and elevated mid-stance hamstring and quadriceps activation.

INTERPRETATION

Altered kinematics and muscle activity could contribute to a greater mechanical demand on the contralateral knee in those with more severe hip osteoarthritis.

Quantifying walking ability in Japanese patients with knee osteoarthritis: Standard values derived from a multicenter study

BACKGROUND

We aimed to determine useful parameters for quantifying walking ability in patients with knee osteoarthritis.

METHODS

This study included 621 Japanese patients with knee osteoarthritis scheduled to undergo total knee arthroplasty at any of 14 participating hospitals. Sex, age, body mass index, osteoarthritis severity (Kellgren-Lawrence grade), laterality, prior contralateral surgery, and pain were analyzed for their influence on walking ability, which was evaluated in terms of the 5-m walk test and the Timed Up and Go test outcomes during preoperative hospitalization. Patients were stratified based on dichotomized values of the independent influencing factors of walking ability, and the standard values for parameters describing walking ability were obtained.

RESULTS

Multiple regression analysis revealed that sex, age, and Kellgren-Lawrence grade were factors influencing walking ability (5-m walk test and Timed Up and Go test outcomes). Therefore, the patients were stratified by sex, age, and Kellgren-Lawrence grade. The standard values (median values) for walking time on the 5-m walk test among patients aged 60-74/75-89 years were: 3.90/4.64 vs. 4.27/5.12 s for men vs. women with Kellgren-Lawrence grade III; 4.26/5.60 vs. 4.80/6.05 s for men vs. women with Kellgren-Lawrence grade IV. Regarding walking speed on the 5-m test, the standard values were: 1.28/1.08 vs. 1.17/0.98 m/s for men vs. women with Kellgren-Lawrence grade III; 1.17/0.89 vs. 1.04/0.83 m/s for men vs. women with Kellgren-Lawrence grade IV. Finally, the standard values for time on the Timed Up and Go test were: 8.52/10.30 vs. 9.30/11.74 s for men vs. women with Kellgren-Lawrence grade III; 9.40/12.90 vs. 10.05/13.20 s for men vs. women with Kellgren-Lawrence grade IV.

CONCLUSIONS

The standard values reported in this study can be used to quantify walking ability decline in patients with knee osteoarthritis and to aid in the decision to consider total knee arthroplasty.

The effect of low-level laser therapy and physical exercise on pain, stiffness, function, and spatiotemporal gait variables in subjects with bilateral knee osteoarthritis: a blind randomized clinical trial

Objective: To evaluate the effects of individual and combination therapies (low-level laser therapy and physical exercises) on pain, stiffness, function, and spatiotemporal gait variables in subjects with bilateral knee osteoarthritis (OA).Methods: Subjects with knee OA (Grades 1-3) were evaluated and randomized into four groups: Control Group (CG), untreated; Laser Group (LG), treated with laser at 808 nm, 5.6 J; Exercise Group (EG), treated with exercise; and Laser + Exercise Group (LEG), treated with laser and exercises. The treatment was carried out twice a week for 2 months. The Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) questionnaire was applied for evaluation and reevaluation; evaluation of spatiotemporal gait variables was performed using GAITRite equipment.Results: The EG showed significant improvement in pain (p = 0.006) and function (p = 0.01) according to WOMAC. Regarding gait variables, in intergroup analysis after 8 weeks all groups receiving intervention showed a significant increase in gait speed: LG versus CG (p = 0.03); EG versus CG (p = 0.04) and LEG versus CG (p = 0.005). Only the group treated with laser + exercise showed a significant increase (p = 0.009) in the cadence and duration of single right limb support (p = 0.04), and only the groups treated with exercise and laser + exercise showed significant decreases in the duration of right limb support (p = 0.035 and p = 0.003, respectively), compared to the CG.Conclusions: The group treated only with exercise showed improvement in WOMAC questionnaire scores. Regarding the gait variables, all groups undergoing the interventions showed increases in the gait speed compared to the CG. The laser and exercise combination therapy provided the best results for the other gait variables (cadence and duration of right limb support and duration of single right limb support).Implications for rehabilitationThere are differences in gait patterns in patients with knee OA, including decreased gait speed, cadence, and step length.The results shown in the present study provide additional information about the physical therapy approaches that should be chosen during clinical practical to improve gait performance in individuals with knee osteoarthritis.The improvement in gait performance is a relevant issue due to the fact that is associated to physical independence and better quality of life.

Knee osteoarthritis phenotypes and their relevance for outcomes: a systematic review

OBJECTIVE

To systematically review the literature for studies investigating knee osteoarthritis (OA) phenotypes to examine what OA characteristics are relevant for phenotyping.

METHODS

A comprehensive search was performed in Medline, EMBASE, Web of Sciences, CINAHL, and Scopus databases from inception to September 2016. Inclusion was limited to observational studies of individuals with symptomatic knee OA that identified phenotypes based on any OA characteristics and assessed their association with clinically important outcomes. A descriptive synthesis of the data was performed.

RESULTS

Of the 2777 citations retrieved, 34 studies were included. Clinical phenotypes were investigated most frequently, followed by laboratory, imaging and aetiologic phenotypes. Eight studies defined subgroups based on outcome trajectories (pain, function and radiographic progression trajectories). Most studies used a single patient or disease characteristic to identify patients subgroups while five included characteristics from multiple domains. We found evidence from multiple studies suggesting that pain sensitization, psychological distress, radiographic severity, body mass index (BMI), muscle strength, inflammation and comorbidities are associated with clinically distinct phenotypes. Gender, obesity and other metabolic abnormalities, the pattern of cartilage damage, and inflammation may be implicated in delineating distinct structural phenotypes. Only a few studies investigated the external validity of the phenotypes or their prospective validity using longitudinal outcomes.

CONCLUSIONS

There is marked heterogeneity in the data selected by the studies investigating knee OA phenotypes. We identified the phenotypic characteristics that can be considered for a comprehensive phenotype classification in future studies. A framework for the investigation of phenotypes could be useful for future studies.

PROTOCOL REGISTRATION

PROSPERO CRD42016036220.

Spatiotemporal and plantar pressure patterns of 1000 healthy individuals aged 3-101 years

OBJECTIVE

The purpose of this study was to establish normative reference values for spatiotemporal and plantar pressure parameters, and to investigate the influence of demographic, anthropometric and physical characteristics.

METHODS

In 1000 healthy males and females aged 3-101 years, spatiotemporal and plantar pressure data were collected barefoot with the Zeno™ walkway and Emed^® platform. Correlograms were developed to visualise the relationships between widely reported spatiotemporal and pressure variables with demographic (age, gender), anthropometric (height, mass, waist circumference) and physical characteristics (ankle strength, ankle range of motion, vibration perception) in children aged 3-9 years, adolescents aged 10-19 years, adults aged 20-59 years and older adults aged over 60 years.

RESULTS

A comprehensive catalogue of 31 spatiotemporal and pressure variables were generated from 1000 healthy individuals. The key findings were that gait velocity was stable during adolescence and adulthood, while children and older adults walked at a comparable slower speed. Peak pressures increased during childhood to older adulthood. Children demonstrated highest peak pressures beneath the rearfoot whilst adolescents, adults and older adults demonstrated highest pressures at the forefoot. Main factors influencing spatiotemporal and pressure parameters were: increased age, height, body mass and waist circumference, as well as ankle dorsiflexion and plantarflexion strength.

CONCLUSION

This study has established whole of life normative reference values of widely used spatiotemporal and plantar pressure parameters, and revealed changes to be expected across the lifespan.

Knee osteoarthritis, degenerative meniscal lesion and osteonecrosis of the knee: Can a simple gait test direct us to a better clinical diagnosis

INTRODUCTION

The purpose of the current study was to compare the gait patterns in patients with three differing knee pathologies - knee osteoarthritis (OA), degenerative meniscal lesion (DML) and spontaneous osteonecrosis of the knee (SONK) and a group of healthy controls.

HYPOTHESIS

A simple gait test will detect differences between different knee pathologies.

MATERIAL AND METHODS

Forty-seven patients with bilateral knee OA, 47 patients with DML, 28 patients with SONK and 27 healthy controls were included in this analysis. Patients underwent a spatiotemporal gait assessment and were asked to complete the Western Ontario and McMaster University (WOMAC) Index and the Short-Form (SF)-36 Health Survey. ANOVA tests, followed by Bonferroni multiple comparison tests and the Chi² tests were performed for continuous and categorical variables, respectively.

RESULTS

Significant differences were found for all gait measures and clinical questionnaires between healthy controls and all knee conditions. Patients with SONK differed from patients with bilateral knee OA and DML in all gait measures and clinical questionnaires, except for WOMAC subscales. There were no significant differences between patients with bilateral knee OA and patients with DML. Symmetry was also examined and revealed asymmetry in some gait parameters in patients with SONK and DML.

DISCUSSION

Based on the differences in gait parameters that were found in the current study, adding an objective functional spatiotemporal gait test may assist in the diagnostic process of knee pathologies.

TYPE OF STUDY

Case Control study Level III.

Dual-belt treadmill familiarization: Implications for knee function in moderate knee osteoarthritis compared to asymptomatic controls

BACKGROUND

Effect of treadmill familiarization on knee function in osteoarthritis is not clear. Purpose was to determine whether spatiotemporal characteristics, knee joint biomechanics and muscle activation patterns change as individuals with and without medial compartment knee osteoarthritis familiarize to dual-belt treadmill walking over 6min.

METHODS

20 individuals with knee osteoarthritis and 20 asymptomatic controls walked at a self-selected speed. Spatiotemporal characteristics, sagittal plane joint motions, sagittal and frontal plane moments and knee joint muscle activation patterns, amplitude normalized to maximum isometric contractions were analyzed. Discrete measures were extracted from each biomechanical waveform and principal component analysis was used to determine knee joint muscle activation patterns. Statistical significance was determined using Analysis of Variance models (alpha=0.05).

FINDINGS

Spatiotemporal gait characteristics, knee motion and moment differences were found between groups however no group by time interactions existed and no changes in these variables were found over 6min of walking. Group differences in muscle activation patterns were found in all muscle activations. Muscle activation amplitude and patterns at minute 5 and 6 were generally lower, less prolonged and more dynamic when compared to minute 1 and 3.

INTERPRETATION

Individuals with and without medial compartment knee osteoarthritis familiarized to treadmill walking in a similar manner. Minimal changes to knee biomechanics were found during treadmill familiarization. Five to six minutes of familiarization should be considered for surface electromyography in these populations.

Correlation between gait analysis and clinical questionnaires in patients with spontaneous osteonecrosis of the knee

BACKGROUND

Spontaneous osteonecrosis of the knee is usually verified by magnetic resonance imaging accompanied by clinical questionnaires to assess the level of pain and functional limitation. There is a lack however, in an objective functional test that will reflect the functional severity of spontaneous osteonecrosis of the knee. The purpose of the current study was to examine the correlation between spatiotemporal gait parameters and clinical questionnaires in patients with spontaneous osteonecrosis of the knee.

METHODS

28 patients (16 females and 12 males) were included in the analysis. Patients had unilateral spontaneous osteonecrosis of the knee of the medial femoral condyle confirmed by magnetic resonance imaging. All patients performed a computerized spatiotemporal gait analysis and completed the Western Ontario and McMaster University Osteoarthritis Index and the Short-Form 36. Relationships between selected spatiotemporal gait measures and self-assessment questionnaires were assessed by Spearman non-parametric correlations.

FINDINGS

Significant correlations were found between selected spatiotemporal gait parameters and clinical questionnaires (r ranged between 0.28 and 0.79). Single limb support was the gait measure with the strongest correlation to pain (r=0.58), function (r=0.56) and quality of life.

INTERPRETATION

Spatiotemporal gait assessment for patients with spontaneous osteonecrosis of the knee correlates with the patient's level of pain and functional limitation there by adding objective information regarding the functional condition of these patients.

Validity and test-retest reliability of the Stride Analyzer in people with knee osteoarthritis

INTRODUCTION

Subjects with knee osteoarthritis walk differently compared to healthy subjects. Managing these gait alterations has been proven effective for reducing pain and increasing function. The Stride Analyzer is a low cost gait analysis tool but its clinimetric properties have not been investigated yet in subjects with symptomatic knee osteoarthritis. The aim of this study was to investigate the reliability and validity of the SA compared with the Gold standard (Vicon) in persons with knee OA.

METHODS

Fifteen subjects with symptomatic knee osteoarthritis were instructed to walk at a self-selected speed in a gait laboratory. Temporospatial (TS) gait parameters were recorded simultaneously by the Stride Analyzer and by a 16-camera-infrared optoelectronic motion capturing system (Vicon). Validity and test-retest reliability of the Stride Analyzer were examined by Bland-Altman plots, intra-class correlation coefficients (ICC) and the standard error of measurement (SEM).

RESULTS

Test-retest analyses showed good agreement for all TS parameters with ICC values ranging from 0.805 (single limb support right) to 0.949 (velocity) and SEM% values ranging from 0.78% (stance phase right (% of gait cycle)) to 4.52% (double limb support right (% of gait cycle)). Good agreement between Stride Analyzer and Vicon was found for the following TS parameters: velocity (z=1.01), cadence (z=-0.85), stride length (z=1.63) and gait cycle (z=0.86). All other gait parameters showed lower ICC values (<0.689).

INTERPRETATION

Our results suggest that the Stride Analyzer can be used in the clinical field to perform gait analysis in subjects with symptomatic knee osteoarthritis.

Effects of Tai Ji Quan training on gait kinematics in older Chinese women with knee osteoarthritis: A randomized controlled trial

BACKGROUND

Although Tai Ji Quan has been shown to relieve pain and improve functional mobility in people with knee osteoarthritis (OA), little is known about its potential benefits on gait characteristics among older Chinese women who have a high prevalence of both radiographic and symptomatic knee OA. This study aims to assess the efficacy of a tailored Tai Ji Quan intervention on gait kinematics for older Chinese women with knee OA.

METHODS

A randomized controlled trial involving 46 older women in Shanghai, China, with clinically diagnosed knee OA. Randomized (1:1) participants received either a 60 min Tai Ji Quan session (n = 23) 3 times weekly or a 60 min bi-weekly educational session (n = 23) for 24 weeks. Primary outcomes were changes in gait kinematic measures from baseline to 24 weeks. Secondary outcomes included changes in scores on the Western Ontario and McMaster University Osteoarthritis Index (WOMAC) and Short Physical Performance Battery (SPPB).

RESULTS

After 24 weeks the Tai Ji Quan group demonstrated better performance in gait velocity (mean difference, 8.40 cm/s, p = 0.01), step length (mean difference, 3.52 cm, p = 0.004), initial contact angle (mean difference, 2.19°, p = 0.01), and maximal angle (mean difference, 2.61°, p = 0.003) of flexed knees during stance phase compared to the control group. In addition, the Tai Ji Quan group showed significant improvement in WOMAC scores (p < 0.01) (mean difference, -4.22 points in pain, p = 0.002; -2.41 points in stiffness, p < 0.001; -11.04 points in physical function, p = 0.006) and SPPB scores (mean difference, 1.22 points, p < 0.001).

CONCLUSION

Among older Chinese women with knee OA, a tailored Tai Ji Quan intervention improved gait outcomes. The intervention also improved overall function as indexed by the WOMAC and SPPB. These results support the use of Tai Ji Quan for older Chinese adults with knee OA to both improve their functional mobility and reduce pain symptomatology.

Gait characteristics and quality of life perception of patients following tibial plateau fracture

INTRODUCTION

The purpose of the current study was to evaluate the long-term functional outcome as measured by gait patterns and quality of life assessment of patients with high-energy tibial plateau fracture compared to matched controls.

MATERIALS AND METHODS

Thirty-eight patients were evaluated in a case-controlled comparison. Twenty-two patients with tibial plateau fracture were evaluated after 3.1 (1.63) years (sd) from injury. Patients underwent a computerized spatiotemporal gait test and completed the SF-12 health survey. 16 healthy subjects, matched for age and gender served as a control group. The main outcome measures for this study were spatiotemporal gait characteristics, physical quality of life and mental quality of life.

RESULTS

Significant differences were found in all gait parameters between patients with tibial plateau fracture and healthy controls. Patients with tibial plateau fracture walked slower by 18% compared to the control group (p < 0.001), had slower cadence by 8% compared (p = 0.002) to the control group and had shorter step length in the involved leg by 11% and in the uninvolved leg by 12% compared to the control group (p = 0.006 and p = 0.003, respectively). Patients with tibial plateau fracture also showed shorter single limb support (SLS) in the involved leg by 12% compared to the uninvolved leg and 5% in the uninvolved leg compared to the control group (p < 0.001 and p = 0.017, respectively). Significant differences were found in the Short Form (SF)-12 scores. Physical Health Score of patients with tibial plateau fracture was 65% lower compared to healthy controls (p < 0.001), and Mental Health Score of the patients was 40% lower compared to healthy controls (p < 0.001). Finally, significant correlations were found between SF-12 and gait patterns.

CONCLUSION

Long-term deviations in gait and quality of life exist in patients following tibial plateau fracture. Patients following tibial plateau fracture present altered spatiotemporal gait patterns compared to healthy controls, as well as self-reported quality of life.

Effect of walking speed on gait sub phase durations

Gait phase durations are important spatiotemporal parameters in different contexts such as discrimination between healthy and pathological gait and monitoring of treatment outcomes after interventions. Although gait phases strongly depend on walking speed, the influence of different speeds has rarely been investigated in literature. In this work, we examined the durations of the stance sub phases and the swing phase for 12 different walking speeds ranging from 0.6 to 1.7 m/s in 21 healthy subjects using infrared cinematography and an instrumented treadmill. We separated the stance phase into loading response, mid stance, terminal stance and pre-swing phase and we performed regression modeling of all phase durations with speed to determine general trends. With an increasing speed of 0.1m/s, stance duration decreased while swing duration increased by 0.3%. All distinct stance sub phases changed significantly with speed. These findings suggest the importance of including all distinct gait sub phases in spatiotemporal analyses, especially when different walking speeds are involved.

Effects of whole-body vibration training with quadriceps strengthening exercise on functioning and gait parameters in patients with medial compartment knee osteoarthritis: a randomised controlled preliminary study

OBJECTIVE

To compare the effects of whole-body vibration training (WBVT) with quadriceps strengthening exercise (QSE) with QSE alone on functioning and gait parameters in patients with medial compartment knee osteoarthritis.

DESIGN

Randomised controlled preliminary study.

SETTING

Department of Rehabilitation Medicine, West China Hospital, Chengdu, Sichuan, People's Republic of China.

SUBJECTS

Thirty-nine patients with medial compartment knee osteoarthritis.

INTERVENTIONS

Participants were assigned at random to one of two groups.

MAIN MEASURES

Visual analogue scale (VAS) for pain, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), timed up and go test (TUG), 6-minute walk distance test (6MWD), and three-dimensional gait analysis during level walking at baseline, 12 weeks and 16 weeks (follow-up).

RESULTS

Compared with baseline, significant improvements in VAS, all WOMAC scales, TUG, 6MWD and all spatiotemporal parameters were seen in both the WBVT+QSE group and the QSE alone group at 12 and 16 weeks. However, the WBVT+QSE group showed greater improvements than the QSE alone group in WOMAC scales (physical function), TUG, 6MWD and cadence at 12 weeks. No differences were found between the WBVT+QSE and QSE alone groups in VAS, WOMAC scales (pain, stiffness), kinematic and kinetic gait parameters, and other spatiotemporal parameters at 12 weeks and 16 weeks.

CONCLUSION

Over a 3-month period, WBVT in combination with QSE improved symptoms, physical function and spatiotemporal parameters in patients with medial compartment knee osteoarthritis, and led to greater improvement than QSE alone in WOMAC scales (physical function), TUG, 6MWD and cadence.

Deviations in gait metrics in patients with chronic ankle instability: a case control study

Background

Gait metric alterations have been previously reported in patients suffering from chronic ankle instability (CAI). Previous studies of gait in this population have been comprised of relatively small cohorts, and the findings of these studies are not uniform. The objective of the present study was to examine spatiotemporal gait metrics in patients with CAI and examine the relationship between self-reported disease severity and the magnitude of gait abnormalities.

Methods

Forty-four patients with CAI were identified and compared to 53 healthy controls. Patients were evaluated with spatiotemporal gait analysis via a computerized mat and with the Short Form (SF) - 36 health survey.

Results

Patients with CAI were found to walk with approximately 16% slower walking velocity, 9% lower cadence and approximately 7% lower step length. Furthermore, the base of support, during walking, in the CAI group was approximately 43% wider, and the single limb support phase was 3.5% shorter compared to the control group.

All of the SF-36 8-subscales, as well as the SF-36 physical component summary and SF-36 mental component summary, were significantly lower in patients with CAI compared to the control group. Finally, significant correlations were found between most of the objective gait measures and the SF-36 mental component summary and SF-36 physical component summary.

Conclusions

The results outline a gait profile for patients suffering from CAI. Significant differences were found in most spatiotemporal gait metrics. An important finding was a significantly wider base of support. It may be speculated that these gait alterations may reflect a strategy to deal with imbalance and pain. These findings suggest the usefulness of gait metrics, alongside with the use of self-evaluation questionnaires, in assessing disease severity of patients with CAI.

Clinical outcomes following ankle fracture: a cross-sectional observational study

Background

The purpose of the current study was to examine objective and subjective differences between three severity groups of ankle fractures patients compared to healthy controls.

Methods

This was a case-controlled study. 92 patients with an ankle fracture injury of which 41 patients were eligible to participate in the study. 72 healthy people served as controls. All patients underwent a computerized gait test, completed self-assessment questionnaires (The Foot and Ankle Outcome Score (FAOS) and the SF-36), evaluated with the American Foot and Ankle Score (AOFAS) form and completed the 6-min walk test. The control group performed a computerized gait test and completed the SF-36 health survey.

Results

All ankle fracture patients presented compromised gait patterns and limb symmetry compared to controls (p < 0.05). Ankle fracture patients also had lower SF-36 scores compared to controls (p < 0.05). Significant differences were found between the unimalleolar group compared to the bimalleolar and trimalleolar groups in most parameters, except for the FAOS scores. There were no significant differences between the bimalleolar fracture group and the trimalleolar fracture groups.

Conclusions

Although all fracture severity classification groups presented a compromised gait pattern and worse clinical symptoms compared to controls, it seems that patients with a unimalleolar fracture is a different group compared to bimalleolar and trimalleolar fracture. Furthermore, it seems that bimalleolar fracture and trimalleolar fracture affect the gait pattern and clinical symptoms to an equal extent, at least in the short-term.

Trial registration

NCT01127776.

Effects of contralateral versus ipsilateral cane use on gait in people with knee osteoarthritis

OBJECTIVE

To compare the immediate effects of contralateral versus ipsilateral cane use on spatiotemporal gait parameters and peak vertical ground force in overweight or obese adults with symptomatic knee osteoarthritis (OA).

DESIGN

Prospective observational study.

SETTING

An academic tertiary Veterans Affairs Healthcare Center.

PARTICIPANTS

Thirty-eight overweight or obese subjects with symptomatic knee OA who had not used a cane for the past 30 days.

METHODS

Spatiotemporal gait data were obtained with an optical motion capture system while subjects walked without a cane, with a cane contralateral to the more painful lower limb, or with a cane ipsilateral to the more painful lower limb at self-selected speeds. An in-shoe dynamic pressure distribution system was used to measure the vertical ground reaction force.

MAIN OUTCOME MEASUREMENTS

Spatiotemporal measures of gait and peak vertical ground reaction force on both lower limbs were recorded for each walking condition: no cane, contralateral cane, and ipsilateral cane.

RESULTS

Walking with a cane either contralateral or ipsilateral to the more symptomatic limb led to significant reductions in gait velocity (14%-16%), cadence (12%-14%), and peak vertical ground reaction force (normalized for body weight; 11%-12%) on the more painful lower limb compared with walking unaided (P < .05). There were no significant differences in the peak vertical ground reaction force on either lower limbs when comparing walking with a cane contralateral to the more painful limb or walking with a cane ipsilateral to the more painful limb. Subjects also experienced a significant decrease in gait velocity with contralateral or ipsilateral cane use compared with walking without a cane; the lower walking speed was due to a decrease in cadence.

CONCLUSIONS

These results support the prescription of a single-point cane to offload a lower limb with painful knee OA by holding the cane either ipsilateral or contralateral to the more painful lower limb.