The role of gait analysis in treating gait abnormalities in cerebral palsy

Kinematic Changes throughout Childhood in Youth with Cerebral Palsy: Influence of Age and Orthopaedic Surgery

BACKGROUND

Abnormal gait kinematics are common in youth with cerebral palsy (CP), but prior studies have not analyzed their longitudinal change throughout childhood. This study examines how age and orthopaedic surgery influence gait kinematics throughout childhood in those with ambulatory CP.

METHODS

In this institutional review board-approved prospective cohort study, children with spastic CP (GMFCS I-III) were recruited at age 17-40 months. Instrumented gait analysis was performed at 3-year intervals from age 4 to 21 years, collecting longitudinal kinematic data in bare feet at a self-selected speed. The change in Gait Profile Score (ΔGPS) between each pair of gait analyses (intervals) was analyzed by age distribution (<10, 10-15, ≥15 years) and by presence/absence of orthopaedic surgery.

RESULTS

The study included 31 children (GMFCS: I [13], II [14], III [4]). A baseline instrumented gait analysis was performed at age 5.8 ± 1.6 years with subsequent analysis at 2.5 ± 1.3-year intervals. Examining ΔGPS from baseline to final outcome, 87% of limbs were improved/unchanged; 298 intervals of ΔGPS were analyzed and classified as nonsurgical or surgical. Analysis revealed greater GPS improvement in intervals with surgery versus intervals without (p = 0.0004). Surgical intervals had significantly greater GPS improvement in the <10- vs. >15-year-old groups, p = 0.0063.

CONCLUSIONS

Improvement in gait kinematics in children with CP is significantly influenced by age and timing of orthopaedic surgical intervention for gait correction, and was most pronounced for children <10 years old. Although surgery was associated with improved outcomes in all age groups, these improvements were significantly less for children >10 years old. These results reinforce the importance of considering the timing of orthopaedic surgery.

Gait Impairment Analysis Using Silhouette Sinogram Signals and Assisted Knowledge Learning

The analysis of body motion is a valuable tool in the assessment and diagnosis of gait impairments, particularly those related to neurological disorders. In this study, we propose a novel automated system leveraging artificial intelligence for efficiently analyzing gait impairment from video-recorded images. The proposed methodology encompasses three key aspects. First, we generate a novel one-dimensional representation of each silhouette image, termed a silhouette sinogram, by computing the distance and angle between the centroid and each detected boundary points. This process enables us to effectively utilize relative variations in motion at different angles to detect gait patterns. Second, a one-dimensional convolutional neural network (1D CNN) model is developed and trained by incorporating the consecutive silhouette sinogram signals of silhouette frames to capture spatiotemporal information via assisted knowledge learning. This process allows the network to capture a broader context and temporal dependencies within the gait cycle, enabling a more accurate diagnosis of gait abnormalities. This study conducts training and an evaluation utilizing the publicly accessible INIT GAIT database. Finally, two evaluation schemes are employed: one leveraging individual silhouette frames and the other operating at the subject level, utilizing a majority voting technique. The outcomes of the proposed method showed superior enhancements in gait impairment recognition, with overall F1-scores of 100%, 90.62%, and 77.32% when evaluated based on sinogram signals, and 100%, 100%, and 83.33% when evaluated based on the subject level, for cases involving two, four, and six gait abnormalities, respectively. In conclusion, by comparing the observed locomotor function to a conventional gait pattern often seen in healthy individuals, the recommended approach allows for a quantitative and non-invasive evaluation of locomotion.

Relationship between spatiotemporal parameters and clinical outcomes in children with bilateral spastic cerebral palsy: Clinical interpretation proposal

BACKGROUND

Understanding the links between gait disorders, impairments, and activity limitations is essential for correctly interpreting the instrumented gait analysis. We aimed to evaluate the relationships between spatiotemporal parameters and clinical outcomes in children with bilateral spastic cerebral palsy, and find out whether spatiotemporal parameters provide clinical information regarding gait pattern and walking.

METHODS

Data from 19 children with bilateral spastic cerebral palsy (nine males, ten females, 9.6 ± 2.8 years old) were collected retrospectively. All children underwent an instrumented gait analysis and a standardized clinical assessment. Seven spatiotemporal parameters were calculated: non-dimensional cadence, stride length, step width, gait speed, first double support, single support, and time of toe off. Clinical outcomes included measures of two different components of the International Classification of Functioning, Disability and Health - Children and Youth version: body functions and structures (spasticity, contractures and range of motion, and deformities), and activities and participation (gross motor function, and walking capacity). Pearson correlation, ANOVA, Student's t, Mann-Whitney U, and Kruskal-Wallis tests were used to analyze relationships. Spatiotemporal parameters related to clinical outcomes of body functions and structures were interpreted as outcome measures of gait pattern, while those related to clinical outcomes of activities and participation were interpreted as outcome measures of walking.

RESULTS

Non-dimensional cadence, stride length, and gait speed showed relationships (p < 0.05) with hip flexors spasticity and hindfoot deformity, ankle plantar flexors spasticity, and hindfoot deformity, respectively. All spatiotemporal parameters except non-dimensional cadence showed correlation (p < 0.05) with gross motor function and walking capacity.

CONCLUSIONS

Spatiotemporal parameters provide clinical information regarding both gait pattern and walking.

The impact of instrumented gait analysis on decision-making in the interprofessional management of cerebral palsy: A scoping review

BACKGROUND

Management of gait-related problems in children and young people with Cerebral Palsy (CYPwCP) is complex and requires an interprofessional approach. Irrespective of underlying mechanisms, instrumented gait analysis (IGA) can provide quantification of gait to support clinical decision-making for CYPwCP when planning treatment interventions.

AIM

This scoping review aimed to determine the impact of instrumented gait analysis (IGA) on treatment decision-making for CYPwCP, paying particular attention to interprofessional decision-making.

METHOD

PubMed, EMBASE, Web of Science and Scopus databases were searched from inception to October 2019 for studies including CYPwCP age<25 years. The PRISMA ScR protocol was followed, and Quality was assessed with the Downs and Black (D&B) scale. Influences on decision-making were coded according to the International Classification of Functioning, Disability and Health for Children and Youth framework (ICF-CY).

RESULTS

Seventeen studies (1144 patients, 2.8-23 years) of varying quality (mean D&B = 17.2, range = 11-26) were included. Studies considered IGA influence at three decision-making stages 'Clinical Planning', 'Treatment Performed' and 'Follow up'. Child and Family, and Clinician and Service-centred factors had a high impact on engagement with IGA recommendations.

INTERPRETATION

IGA guided recommendations can differ from initial clinical plans, and often lead to modification of the treatment ultimately performed. The effect on individual patients' outcomes when treatment recommendations based on instrumented gait analysis are followed is not yet clear and warrants further research. The differences in clinicians' engagement with IGA recommendations occur due to an array of Child and Family, and Clinician and Service-centred factors. Overall, IGA leads to less surgical recommendations, and has the potential to influence conservative gait-related management in CYPwCP.

Motion laboratory gait analysis and orthopedic resident education: preliminary results

Gait analysis in the pediatric and adult orthopedic patient populations can adjunct the diagnosis and treatment of a multitude of musculoskeletal conditions. Understanding of normal and abnormal gait biomechanics is an important aspect of orthopedic residency; yet, there is great variability in the time residency programs dedicate to gait analysis education. The purpose of this study was to investigate if formal gait analysis education during residency improves an orthopedic resident's understanding of normal and pathologic gait. Five residency programs consisting of 81 resident subjects were surveyed at the beginning of the 2016-2017 academic year. The residents were divided into those with formal gait analysis education (group A) and those without (group B). Each resident was sent an online survey with 11 questions from former orthopedic in-training exams (OITE) regarding gait pattern analysis. The average number of correct questions was compared between the two groups with Student's t-test. Fifty-three of the 81 surveys sent out were completed. There were 23 subjects in group A and 30 in group B. All five programs and all postgraduate years (PGYs) were represented (PGY1: 10, PGY2: 12, PGY3: 12, PGY4: 6, PGY5 12). The average score for all residents was 5.6 out of 11 correct (51%). The residents from group A averaged a significantly higher score (6.3) than group B (5.0) (P = 0.017). Understanding gait biomechanics is a critical skill for orthopedic surgeons, and residency training often lacks sufficient training in their curriculum. A good understanding of gait analysis allows orthopedic surgeons to analyze gait disturbances and develop patient-specific treatment plans in adult and pediatric populations. This study found improved knowledge of gait patterns amongst orthopedic residents with formal education. Even though the residents with formal education fared better than their counterparts, the overall percent correct was still low (51%). Evidence: Level 3: Prospective Cohort Study.

Gait event detection using kinematic data in children with bilateral spastic cerebral palsy

BACKGROUND

Ground reaction forces are the gold standard for detecting gait events, but they are not always applicable in cerebral palsy. Ghoussayni's algorithm is an event detection method based on the sagittal plane velocity of heel and toe markers. We aimed to evaluate whether Ghoussayni's algorithm, using two different thresholds, was a valid event detection method in children with bilateral spastic cerebral palsy. We also aimed to define a new adaptation of Ghoussayni's algorithm for detecting foot strike in cerebral palsy, and study the effect of event detection methods on spatiotemporal parameters.

METHODS

Synchronized kinematic and kinetic data were collected retrospectively from 16 children with bilateral spastic cerebral palsy (7 males and 9 females; age 8.9 ± 2.7 years) walking barefoot at self-selected speed. Gait events were detected using methods: 1) ground reaction forces, 2) Ghoussayni's algorithm with a threshold of 0.5 m/s, and 3) Ghoussayni's algorithm with a walking speed dependent threshold. The new adaptation distinguished how foot strikes were performed (heel and/or toe) comparing the timing when the foot markers velocities fell below the threshold. Differences between the three methods, and between spatiotemporal parameters calculated from the two Ghoussayni's thresholds were analyzed.

FINDINGS

There were statistically significant (P < 0.05) differences between methods 1 and 3, and between some spatiotemporal parameters calculated from methods 2 and 3. Ghoussayni's algorithm showed better performance for foot strike than for toe off.

INTERPRETATION

Ghoussayni's algorithm using 0.5 m/s is valid in children with bilateral spastic cerebral palsy. Event detection methods affect spatiotemporal parameters.

Technological advancements in the analysis of human motion and posture management through digital devices

Technological development of motion and posture analyses is rapidly progressing, especially in rehabilitation settings and sport biomechanics. Consequently, clear discrimination among different measurement systems is required to diversify their use as needed. This review aims to resume the currently used motion and posture analysis systems, clarify and suggest the appropriate approaches suitable for specific cases or contexts. The currently gold standard systems of motion analysis, widely used in clinical settings, present several limitations related to marker placement or long procedure time. Fully automated and markerless systems are overcoming these drawbacks for conducting biomechanical studies, especially outside laboratories. Similarly, new posture analysis techniques are emerging, often driven by the need for fast and non-invasive methods to obtain high-precision results. These new technologies have also become effective for children or adolescents with non-specific back pain and postural insufficiencies. The evolutions of these methods aim to standardize measurements and provide manageable tools in clinical practice for the early diagnosis of musculoskeletal pathologies and to monitor daily improvements of each patient. Herein, these devices and their uses are described, providing researchers, clinicians, orthopedics, physical therapists, and sports coaches an effective guide to use new technologies in their practice as instruments of diagnosis, therapy, and prevention.

Radiographic and plantar pressure assessment of pes planovalgus severity in children with cerebral palsy

BACKGROUND

Pes planovalgus is common in children with cerebral palsy. Although severity influences treatment, there still lacks standard clinical measurements to objectively quantify pes planovalgus in this population. The comparison of pedobarographic data and radiographic measurements to clinical evaluation has not been reported in this population.

METHODS

395  feet were identified from a population of ambulatory pediatric patients with cerebral palsy. Each patient initially underwent clinical evaluation by an experienced physical therapist who classified feet as: 136 controls, 116 mild, 100 moderate, and 43 severe pes planovalgus. Quantitative measurements were then calculated from antero-posterior and lateral radiographs of the foot. Pedobarographic analysis included the arch index, center of pressure index, and a newly defined medial index.

FINDINGS

A multivariate analysis was performed on the radiographic and pedobarographic measurements collected. It identified seven variables that improved objective classification of pes planovalgus severity when utilized together. These include the foot progression angle, initial contact force, arch index, medial index, antero-posterior talonavicular coverage, lateral calcaneal pitch and lateral Meary's angle. While the lateral calcaneal pitch angle statistically differed amongst all severity classes, no pedobarographic value statistically differed between all severity classes.

INTERPRETATION

Overall, the combination of radiographic and pedobarographic measurements provides valuable information for objectively classifying severity of pes planovalgus in children with cerebral palsy by utilizing these values together rather than independently. In a clinical setting, radiographs and pedobarographic data may be obtained to enhance assessment of severity and guide treatment.

Distal Femoral Shortening Osteotomy for Severe Knee Flexion Contracture and Crouch Gait in Cerebral Palsy

Although there have been advancements of surgical techniques to correct gait abnormalities seen in patients with cerebral palsy, the crouch gait remains one of the most difficult problems to treat. The purpose of this retrospective study was to examine our results of distal femoral shortening osteotomy (DFSO) and patellar tendon advancement (PTA), performed in patients with crouch gait associated with severe knee flexion contracture. A total of 33 patients with a mean fixed knee contracture of 38° were included in the study. The mean age at the time of surgery was 12.2 years and the mean follow-up was 26.9 months. The measurements of clinical, radiological, and gait parameters were performed before and after surgery. The mean degrees of knee flexion contracture, Koshino index of patella height, and Gait Deviation Index were found to be significantly improved at the time of final follow-up. The maximum knee extension during the stance phase improved by an average of 25°, and the range of knee motion during gait increased postoperatively. On the other hand, the mean anterior pelvic tilt increased by 9.9°. Also, the maximum knee flexion during the swing phase decreased and the timing of peak knee flexion was observed to be delayed. We conclude that combined procedure of DFSO and PTA is an effective and safe surgical method for treating severe knee flexion contracture and crouch gait. However, the surgeons should be aware of the development of increased anterior pelvic tilt and stiff knee gait after the index operation.

Does the Femoral Head Size in Hip Arthroplasty Influence Lower Body Movements during Squats, Gait and Stair Walking? A Clinical Pilot Study Based on Wearable Motion Sensors

A hip prosthesis design with larger femoral head size may improve functional outcomes compared to the conventional total hip arthroplasty (THA) design. Our aim was to compare the range of motion (RoM) in lower body joints during squats, gait and stair walking using a wearable movement analysis system based on inertial measurement units (IMUs) in three age-matched male groups: 6 males with a conventional THA (THAC), 9 with a large femoral head (LFH) design, and 8 hip- and knee-asymptomatic controls (CTRL). We hypothesized that the LFH design would allow a greater hip RoM, providing movement patterns more like CTRL, and a larger side difference in hip RoM in THAC when compared to LFH and controls. IMUs were attached to the pelvis, thighs and shanks during five trials of squats, gait, and stair ascending/descending performed at self-selected speed. THAC and LFH participants completed the Hip dysfunction and Osteoarthritis Outcome Score (HOOS). The results showed a larger hip RoM during squats in LFH compared to THAC. Side differences in LFH and THAC groups (operated vs. non-operated side) indicated that movement function was not fully recovered in either group, further corroborated by non-maximal mean HOOS scores (LFH: 83 ± 13, THAC: 84 ± 19 groups, vs. normal function 100). The IMU system may have the potential to enhance clinical movement evaluations as an adjunct to clinical scales.

Hamstring lengthening in females with cerebral palsy have greater effect than in males

Children with spastic diplegia cerebral palsy often demonstrate crouched gait patterns, and typically undergo hamstring lengthenings. The objective of this retrospective study was to determine if the surgical response to medial and lateral hamstring lengthenings is different between males and females. Preoperative and postoperative kinematic data of 109 (71 males and 38 females) patients with cerebral palsy were evaluated. Females demonstrated larger decreases in popliteal angle, larger decreases in mid-stance knee flexion, and higher incidences of knee hyperextension postoperatively. Results indicate that females have larger responses to hamstring lengthenings than males.

Gait parameters in children with bilateral spastic cerebral palsy: a systematic review of randomized controlled trials

AIM

To identify the gait parameters used to assess gait disorders in children with bilateral spastic cerebral palsy (CP) and evaluate their responsiveness to treatments.

METHOD

A systematic search within PubMed, Web of Science, and Scopus (in English, 2000-2016) for randomized controlled trials of children with bilateral spastic CP who were assessed by instrumented gait analysis (IGA) was performed. Data related to participants and study characteristics, risk of bias, and outcome measures were collected. A list of gait parameters responsive to clinical interventions was obtained.

RESULTS

Twenty-one articles met the inclusion criteria. Eighty-nine gait parameters were identified, 56 of which showed responsiveness to treatments. Spatiotemporal and kinematic parameters were widely used compared to kinetic and surface electromyography data. The majority of responsive gait parameters were joint angles at the sagittal plane (flexion-extension).

INTERPRETATION

The IGA yields responsive outcome measures for the gait assessment of children with bilateral spastic CP. Spatiotemporal and kinematic (at sagittal plane) parameters are the gait parameters used most frequently. Further research is needed to establish the relevant gait parameters for each clinical problem.

WHAT THIS PAPER ADDS

Fifty-six responsive gait parameters for children with bilateral spastic cerebral palsy were identified. Most responsive gait parameters belong to joint angles time-series at sagittal plane. Spatiotemporal and kinematic parameters are widely used compared to kinetic and surface electromyography parameters.

Identification of gait events in children with spastic cerebral palsy: comparison between the force plate and algorithms

OBJECTIVE

To compare the gait event identification of five algorithms recommended in the literature with those provided by force plate (gold standard) in children with unilateral or bilateral spastic cerebral palsy (SCP).

METHODS

This was a cross-sectional study of the gait of three girls and four boys with a mean age of 8.6±4.7 years. Four children had unilateral SCP with an equinus gait pattern, and the remaining three children exhibited bilateral SCP with a slide/drag gait pattern. Kinematic and kinetic gait data were collected during barefoot walking at a comfortable speed. From a total of 202 steps, the detection of 202 foot-strike (FS) and 194 toe-off (TO) events by each algorithm was compared with the detection of these same events by the force plate. The error between the events detected by the algorithms and those detected by the force plate was determined in milliseconds. Repeated measures ANOVA was used to compare the errors among the algorithms.

RESULTS

The algorithm reported by Ghoussayni et al. showed the best performance in all situations, except for the identification of FS events on the unaffected side in children with unilateral SCP. For these events, the algorithms reported by Desailly et al. and Zeni et al. showed the best performance.

CONCLUSION

Ghoussayni et al.'s algorithm can be used to detect gait events in children with SCP when a force plate is not available.

Application of supervised machine learning algorithms in the classification of sagittal gait patterns of cerebral palsy children with spastic diplegia

Gait classification has been widely used for children with cerebral palsy (CP) to assist with clinical decision making and to evaluate different treatment outcomes. The aim of this study was to evaluate supervised machine learning algorithms in the classification of sagittal gait patterns for CP children with spastic diplegia. Gait parameters were extracted from gait data obtained from two hundred children with spastic diplegia CP, and were used to represent the key kinematic features of each individual's gait. Seven supervised machine learning algorithms including an artificial neural network (ANN), discriminant analysis, naive Bayes, decision tree, k-nearest neighbors (KNN), support vector machine (SVM), and random forest were compared by constructing a gait classification system based on the same gait data. The performance of these algorithms was then evaluated using a standard 10-fold cross-validation procedure. The results show that the ANN has the best prediction accuracy (93.5%) with a low resubstitution error (5.8%), high specificity (>0.93) and high sensitivity (>0.92). The decision tree algorithm, SVM, and random forest approaches also have high prediction accuracy (>77.9%) with low resubstitution error (<14.3%), moderate specificity (>0.5) and moderate sensitivity (>0.2). The discriminant analysis, naive Bayes and KNN methods have relatively poor classification performance. Given these results for classification performance and prediction accuracy, the ANN is a good candidate for gait classifications for CP children with spastic diplegia. The decision tree is also attractive for clinical applications due to its transparency. Supervised machine learning algorithms can potentially be integrated into an expert gait analysis system that can interpret gait data and automatically generate high-quality analyses.

Relative phase measures of intersegmental coordination describe motor control impairments in children with cerebral palsy who exhibit stiff-knee gait

BACKGROUND

The purpose of this retrospective study was to explore lower limb intersegmental coordination as a clinically important indicator of motor control mechanisms in individuals with cerebral palsy exhibiting stiff-knee gait. We used the relative phase of thigh and foot segments around foot-off to describe motor control, given the relevance of the pre-swing phase of gait to the existence of stiff-knee gait.

METHODS

Traditional gait parameters and thigh/foot intersegmental coordination were calculated using pre-and postoperative kinematic data from a cohort of 54 subjects (92 legs) with spastic cerebral palsy. All participants had stiff-knee gait, walked without assistive devices, and underwent rectus femoris transfer surgery to improve swing period knee flexion. Analyses included correlations between a) preoperative intersegmental coordination and gait variables (knee flexion range, rate and gait performance) and b) pre-to-postoperative intersegmental coordination change and change in gait variables.

FINDINGS

Thigh/foot intersegmental coordination significantly (P < 0.001) correlated with knee flexion range, rate and walking speed. Postoperative intersegmental coordination was significantly more uncoupled than preoperative. Pre-to-postoperative intersegmental coordination improvement also significantly correlated with improvements in knee flexion range, rate and walking speed. Pre-to-postoperative changes in intersegmental coordination accounted for 43% and 36% of variance in knee flexion range change and knee flexion rate change respectively.

INTERPRETATION

Intersegmental coordination is a clinically important factor in knee flexion limitations associated with stiff-knee gait for individuals with cerebral palsy. These findings are a foundation for further study of intersegmental coordination measures as complements to traditional instrumented gait analysis.

Multi-joint gait clustering for children and youth with diplegic cerebral palsy

Background

Clinical management of children and youth with cerebral palsy (CP) is increasingly supported by computerized gait analysis. Methods have been developed to reduce the complexity of interpreting biomechanical data and quantify meaningful movement patterns. However, few methods are inclusive of multiple joints and planes of motion, and consider the entire duration of gait phases; potentially limiting insight into this heterogeneous pathology. The objective of this study was to assess the implementation of k-means clustering to determine clusters of participants with CP based on multi-joint gait kinematics.

Methods

Barefoot walking kinematics were analyzed for a historical cohort (2007–2015) of 37 male and female children and youth with spastic diplegic CP [male n = 21; female n = 16; median age = 12 (range 5–25) years; Gross Motor Function Classification System Level I n = 17 and Level II n = 20]. Mean stance phase hip (sagittal, coronal, transverse), knee (sagittal), and ankle (sagittal) kinematics were time (101 data points), mean and range normalized. Normalized kinematics data vectors (505 data points) for all participants were then combined in a single data matrix M (37x505 data points). K-means clustering was conducted 10 times for all data in M (2–5 seeds, 50 repetitions). Cluster quality was assessed using the mean Silhouette value (s¯) and cluster repeatability. The mean kinematic patterns of each cluster were explored with respect to a dataset of normally developing (ND) children using Statistical Parametric Mapping (SPM, alpha 0.05). Differences in potentially confounding variables (age, height, weight, walking speed) between clusters (C) were assessed individually in SPSS (IBM, USA) using Kruskal-Wallis H tests (alpha 0.05).

Results

Four clusters (n₁ = 5, n₂ = 12, n₃ = 12, n₄ = 8) provided the largest possible data separation based on high cluster repeatability (96.8% across 10 repetitions) and comparatively greater cluster quality [s¯ (SD), 0.275 (0.152)]. Participant data with low cluster quality values displayed a tendency toward lower cluster allocation repeatability. Distinct kinematic differences between clusters and ND data were observable. Specifically, C1 displayed a unique continuous hip abduction and external rotation pattern. In contrast, participants in C2 moved from hip adduction (loading response) to abduction (mid to terminal stance) and featured a unique ankle plantarflexor pattern during pre-swing. C3 was characterized by gait deviations in the sagittal plane of the hip, knee and ankle only. C4 displayed evidence for the most substantial hip and knee extension, and ankle plantarflexion deficit from midstance to pre-swing.

Discussion

K-means clustering enabled the determination of up to four kinematic clusters of individuals with spastic diplegic CP using multi-joint angles without a priori data reduction. A cluster boundary effect was demonstrated by the Silhouette value, where data with values approaching zero were more likely to change cluster allocation. Exploratory analyses using SPM revealed significant differences across joints and between clusters indicating the formation of clinically meaningful clusters. Further work is needed to determine the effects of including further topographical classifications of CP, additional biomechanical data, and the sensitivity to clinical interventions to assess the potential for informing clinical decision-making.

Neurophysiology of gait

Beyond the classic clinical description, recent studies have quantitatively evaluated gait and balance dysfunction in cerebellar ataxias by means of modern motion analysis systems. These systems have the aim of clearly and quantitatively describing the differences, with respect to healthy subjects, in kinematic, kinetic, and surface electromyography variables, establishing the basis for a rehabilitation strategy and assessing its efficacy. The main findings which characterize the gait pattern of cerebellar patients are: increased step width, reduced ankle joint range of motion with increased coactivation of the antagonist muscles, and increased stride-to-stride variability. Whereas the former is a compensatory strategy adopted by patients to keep the center of mass within the base of support, the latter indicates the inability of patients to maintain dynamic balance through a regular walking pattern and may reflect the primary deficit directly related to cerebellar dysfunction and the consequent lack of muscle coordination during walking. Moreover, during the course of the disease, with the progressive loss of walking autonomy, step length, and lower-limb joint range of motion are drastically reduced. As to the joint coordination defect, abnormal intralimb joint coordination during walking, in terms of both joint kinematics and interaction torques, has been reported in several studies. Furthermore, patients with cerebellar ataxia show a poor intersegmental coordination, with a chaotic coordinative behavior between trunk and hip, leading to increased upper-body oscillations that affect gait performance and stability, sustaining a vicious circle that transforms the upper body into a generator of perturbations. The use of motion analysis laboratories allows a deeper segmental and global characterization of walking impairment in these patients and can shed light on the nature of both the primary specific gait disorder and compensatory mechanisms. Such deeper understanding might reasonably represent a valid prerequisite for establishing better-targeted rehabilitation strategies.

SIAMOC position paper on gait analysis in clinical practice: General requirements, methods and appropriateness. Results of an Italian consensus conference

Gait analysis is recognized as a useful assessment tool in the field of human movement research. However, doubts remain on its real effectiveness as a clinical tool, i.e. on its capability to change the diagnostic-therapeutic practice. In particular, the conditions in which evidence of a favorable cost-benefit ratio is found and the methodology for properly conducting and interpreting the exam are not identified clearly. To provide guidelines for the use of Gait Analysis in the context of rehabilitation medicine, SIAMOC (the Italian Society of Clinical Movement Analysis) promoted a National Consensus Conference which was held in Bologna on September 14th, 2013. The resulting recommendations were the result of a three-stage process entailing i) the preparation of working documents on specific open issues, ii) the holding of the consensus meeting, and iii) the drafting of consensus statements by an external Jury. The statements were formulated based on scientific evidence or experts' opinion, when the quality/quantity of the relevant literature was deemed insufficient. The aim of this work is to disseminate the consensus statements. These are divided into 13 questions grouped in three areas of interest: 1) General requirements and management, 2) Methodological and instrumental issues, and 3) Scientific evidence and clinical appropriateness. SIAMOC hopes that this document will contribute to improve clinical practice and help promoting further research in the field.

Effects of hip joint centre mislocation on gait kinematics of children with cerebral palsy calculated using patient-specific direct and inverse kinematic models

Joint kinematics can be calculated by Direct Kinematics (DK), which is used in most clinical gait laboratories, or Inverse Kinematics (IK), which is mainly used for musculoskeletal research. In both approaches, joint centre locations are required to compute joint angles. The hip joint centre (HJC) in DK models can be estimated using predictive or functional methods, while in IK models can be obtained by scaling generic models. The aim of the current study was to systematically investigate the impact of HJC location errors on lower limb joint kinematics of a clinical population using DK and IK approaches. Subject-specific kinematic models of eight children with cerebral palsy were built from magnetic resonance images and used as reference models. HJC was then perturbed in 6mm steps within a 60mm cubic grid, and kinematic waveforms were calculated for the reference and perturbed models. HJC perturbations affected only hip and knee joint kinematics in a DK framework, but all joint angles were affected when using IK. In the DK model, joint constraints increased the sensitivity of joint range-of-motion to HJC location errors. Mean joint angle offsets larger than 5° were observed for both approaches (DK and IK), which were larger than previously reported for healthy adults. In the absence of medical images to identify the HJC, predictive or functional methods with small errors in anterior-posterior and medial-lateral directions and scaling procedures minimizing HJC location errors in the anterior-posterior direction should be chosen to minimize the impact on joint kinematics.

A Systematic Review of the Effects of Single-Event Multilevel Surgery on Gait Parameters in Children with Spastic Cerebral Palsy

BACKGROUND

Three-dimensional gait analysis (3DGA) is commonly used to assess the effect of orthopedic single-event multilevel surgery (SEMLS) in children with spastic cerebral palsy (CP).

PURPOSE

The purpose of this systematic review is to provide an overview of different orthopedic SEMLS interventions and their effects on 3DGA parameters in children with spastic CP.

METHODS

A comprehensive literature search within six databases revealed 648 records, from which 89 articles were selected for the full-text review and 24 articles (50 studies) included for systematic review. The Oxford Centre for Evidence-Based Medicine Scale and the Methodological Index for Non-Randomized Studies (MINORS) were used to appraise and determine the quality of the studies.

RESULTS

Except for one level II study, all studies were graded as level III according to the Oxford Centre for Evidence-Based Medicine Scale. The MINORS score for comparative studies (n = 6) was on average 15.7/24, while non-comparative studies (n = 18) scored on average 9.8/16. Nineteen kinematic and temporal-distance gait parameters were selected, and a majority of studies reported improvements after SEMLS interventions. The largest improvements were seen in knee range of motion, knee flexion at initial contact and minimal knee flexion in stance phase, ankle dorsiflexion at initial contact, maximum dorsiflexion in stance and in swing phase, hip rotation and foot progression angles. However, changes in 3DGA parameters varied based on the focus of the SEMLS intervention.

DISCUSSION

The current article provides a novel overview of a variety of SEMLS interventions within different SEMLS focus areas and the post-operative changes in 3DGA parameters. This overview will assist clinicians and researchers as a potential theoretical framework to further improve SEMLS techniques within different SEMLS focus groups. In addition, it can also be used as a tool to enhance communication with parents, although the results of the studies can't be generalised and a holistic approach is needed when considering SEMLS in a child with spastic CP.

Biomechanical Assessment of Patellar Advancement Procedures for Patella Alta

Crouch gait deformity is common in children with cerebral palsy and often is associated with patella alta. Patellar tendon advancement typically is used to correct patella alta and restore normal knee mechanics. The purpose of this study was to determine the mechanical strength of surgical constructs used for fixation during patellar advancement procedures. This study used a cadaveric model to determine which of 3 surgical techniques is biomechanically optimal for patellar tendon advancement in treating patella alta. Twenty-four human cadaveric knees (8 per group) were prepared using 1 of 3 different common surgical techniques: tibial tubercle osteotomy, patellar tendon partial resection and repair at the distal patella, and patellar tendon imbrication. The patella was loaded from 25 to 250 N at 1 Hz for 1000 cycles. A significant difference in patella displacement under cyclical loading was found between surgical techniques. Tibial tubercle osteotomy exhibited significantly less displacement under cyclical loading than distal patella excision and repair (P<.0001) or imbrication (P=.0088). Imbrication exhibited significantly less displacement than distal patella excision and repair (P=.0006). Tibial tubercle osteotomy survived longest. Based on failure criteria of 5 mm of displacement, tibial tubercle osteotomy lasted between 250 and 500 cycles. The other 2 techniques failed by 25 cycles. This study offers quantitative evidence regarding the relative mechanical strength of each construct and may influence choice of surgical technique. [Orthopedics. 2016; 39(3):e492-e497.].

Effects of combined Adeli suit and neurodevelopmental treatment in children with spastic cerebral palsy with gross motor function classification system levels I and II

Background:

Children with cerebral palsy (CP) exhibit diverse gait patterns depending on their neurological deficits and musculoskeletal problems. The Adeli suit treatment (AST) has been proposed as an intensive exercise protocol in the management of CP.

Objectives:

The aim of this study was to compare the effects of a 6-week programme of combined AST and neurodevelopment treatment (NDT) with those of NDT alone on Gross Motor Function Measure (GMFM), balance, and gait in children with CP.

Methods:

Twenty children with CP of Gross Motor Function Classification System levels I and II were randomly assigned to one of the following two groups: (1) NDT or (2) AST/NDT. The participants were assessed using the GMFM, Pediatric Balance Scale (PBS), Timed Up and Go (TUG) test, and spatiotemporal gait parameters.

Results:

The GMFM, PBS, and TUG test for both groups showed a statistically significant increase (p < 0.05). Three children were excluded. Compared to the NDT group (n = 9), the AST/NDT group (n = 8) demonstrated a significant increase in spatiotemporal gait parameters (p < 0.05).

Conclusion:

These results provide evidence for the greater effectiveness of combined AST/NDT than NDT alone in improving spatiotemporal gait parameters but not GMFM, PBS, and TUG test.

Foot pressure distribution in children with cerebral palsy while standing

Foot deformity is a major component of impaired functioning in cerebral palsy (CP). While gait and balance issues related to CP have been studied extensively, there is little information to date on foot-ground interaction (i.e. contact area and plantar pressure distribution). This study aimed to characterize quantitatively the foot-ground contact parameters during static upright standing in hemiplegia and diplegia. We studied 64 children with hemiplegia (mean age 8.2 years; SD 2.8 years) and 43 with diplegia (mean age 8.8 years; SD 2.3 years) while standing on both legs statically on a pressure sensitive mat. We calculated pressure data for the whole foot and sub-regions (i.e. rearfoot, midfoot and forefoot) and average contact pressure. The Arch Index (AI) served for classifying the feet as flat, normal or cavus feet. The data were compared with those from a sample of age- and gender-matched participants (control group, 68 children). Most of the feet showed very high AI values, thus indicating a flat foot. This deformity was more common in diplegia (74.4%) than in hemiplegia (54.7%). In both diplegic and hemiplegic children, average plantar pressure was significantly increased in the forefoot and midfoot and decreased in the rearfoot (p<0.001). The present data indicate an increased load on the front parts of the foot, which may be due to plantarflexor overactivity or knee flexion, combined with an increased incidence of low foot arches. As a low foot arch does not necessarily increase forefoot load, this deformity can be regarded as secondary.

Influence of body weight unloading and support surface during walking of children with cerebral palsy

Introduction Partial body weight support (BWS) systems have been employed for gait training of children with cerebral palsy (CP). Therefore, it would be important to analyze if the type of walking surface and the amount of body weight unloading over lower limbs change the way these children walk. Objectives Investigate the influence of walking surface and amount of body weight unloading on the spatial temporal characteristics during walking of children with CP. Materials and methods Seven children with spastic CP between four and eight years old and GMFCS (Gross Motor Function Classification System) between I and IV, were videotaped walking with 0%, 15% and 30% of BWS on both dynamic (treadmill) and static (ground level) surfaces. Walking spatial temporal variables were calculated. Results Children walked with similar velocity in all experimental conditions. While stance duration decreased as the percentage of BWS increased, no differences were found for stance and swing periods and cadence. Children walked with longer steps and strides and with faster strides on static surface compared to dynamic surface. Conclusion Children with CP presenting different levels of motor impairment presented some alterations in the spatial temporal walking parameters as they walked with body unloading. However, such alterations might be due mainly to the type of walking surface than the percentage of body weight unloading on lower limbs.

Gait characteristics of children with cerebral palsy as they walk with body weight unloading on a treadmill and over the ground

Body weight support (BWS) has become a typical strategy for gait training, in special with children with cerebral palsy (CP). Although several findings have been reported in the literature, it remains uncertain how different types of surfaces and gradual amount of BWS can facilitate the mobility of children with CP. The aim of this study was to investigate gait kinematic parameters of children with CP by manipulating BWS and two different types of ground surfaces. Ten children (7.7 ± 2.1 years old) diagnosed with spastic CP and GMFCS classification between levels II and IV were asked to walk on a treadmill and over the ground. In both conditions, BWS was manipulated to minimize gravitational effects and spatial-temporal gait parameters and lower limb joints were analyzed. The results revealed that the type of ground surface causes greater impact on the gait pattern of children with CP as compared to body weight unloading. This finding may provide new insights into the behavioral heterogeneity of children with CP, and offers critical information to be considered on interventional programs specifically designed to improve mobility on this population.

Spastic diplegia in children with HIV encephalopathy: first description of gait and physical status

AIM

The aim of this study was to explore the physical status and gait patterns of children with spastic diplegia secondary to human immunodeficiency virus encephalopathy (HIVE).

METHOD

A cross-sectional study was conducted on children diagnosed with HIVE and spastic diplegia. Sociodemographic and clinical background information was obtained, followed by three-dimensional gait analysis (3DGA) and a physical examination including assessments of muscle tone, strength, motor control, contractures, and bony deformities of the lower extremities.

RESULTS

Fourteen children (eight males, six females; mean age 5 y 8 mo [SD 9 mo], range 4 y 4 mo-6 y 10 mo) were studied. The cohort was divided into two groups based on distinctive gait patterns. Nine participants in group I showed only limited abnormalities. Group II displayed a more pathological gait pattern including stiff knee and equinus ankle abnormalities. Results of 3DGA, as with the physical examination outcomes, showed increased impairments from proximal to distal (except for hip extension).

INTERPRETATION

This study provides a first description of distinctive gait patterns and related physical characteristics of children with HIVE and spastic diplegia. Further research is necessary.

Level versus inclined walking: ambulatory compensations in children with cerebral palsy under outdoor conditions

PURPOSE

To investigate how children with cerebral palsy (CP) adapt their gait to inclined outdoor walking conditions.

METHODS

Ten children with CP, Gross Motor Function System level II, and 10 children with typical development participated. Walking velocity, stride length and ankle, knee, hip, and trunk sagittal plane angles were calculated for 4 conditions: indoor walkway, outdoor walkway, and walking up and down a 7° inclined ramp.

RESULTS

Gait patterns were unchanged between indoor and outdoor level walking. During up-slope walking, both groups increased hip and knee flexion at foot strike to accommodate the slope. During down-slope walking, both groups increased knee flexion in midstance to lower the body down the slope. Children with CP had greater forward trunk lean (P < .005) during up-slope walking and greater posterior trunk lean during down-slope walking (P < .0001).

CONCLUSION

Children with CP adapt to inclined walking conditions similarly to peers but use greater postural adaptations.

Reliability of head and trunk kinematics during gait in children with spastic diplegia

This study describes the reliability of a clinically oriented model for three-dimensional movement analysis of head and trunk movements in children with spastic diplegia. The model consists of five rigid segments (head, thorax, pelvis, shoulder line, spine) and includes a detailed analysis of spinal segmental movements. Within and between session reliability during gait was tested in 10 children with spastic diplegia (6-14yrs). Reliability of discrete parameters was assessed with the intraclass correlation coefficient (ICC) and similarity of thorax and pelvis waveforms with the coefficient of multiple correlation (CMC). Measurement errors were calculated for all parameters (SEM, σ). Results indicated acceptable within and between session reliability of discrete parameters for thorax, pelvis, shoulder line, angle of kyphosis and the majority of the spinal segmental angles, reflected by low SEMs (<4°) and most ICCs>0.60. Within and between session waveform errors were below 4°. CMCs ranged from poor to very good, with highest values for movements in the frontal and transversal planes. The angle of lordosis showed lower between session reliability for several discrete parameters, although waveform errors were still below 5°. Head parameters showed lower overall reliability. The results of this study support the reliability of the proposed model. Head kinematic parameters should be interpreted with caution, due to difficulties in standardization. Accurate palpation of the spinal markers, especially the lumbar spine, is critical and demands thorough training of the assessor.