The role of gait analysis in the orthopaedic management of ambulatory cerebral palsy

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.

Wand-mounted lateral markers are less prone to misplacement and soft-tissue artefacts than skin-mounted markers when using the conventional gait model

BACKGROUND

The conventional gait model (CGM1) is extensively used for 3D clinical gait analysis. It uses lateral wand-mounted markers for the thigh and shank segments to avoid colinearity of the tracking markers. However, gait analysts may be tempted to use skin-mounted markers instead.

RESEARCH QUESTION

Does it matter if the lateral markers for the thigh and shank segments are mounted on wands or directly taped to the skin when using the CGM1?

METHODS

Gait sessions from 147 and 73 patients equipped with wand-mounted and skin-mounted markers, respectively, were extracted from the database of a single clinical gait laboratory. The marker trajectories were reprocessed with the CGM1. The risk of marker colinearity was assessed from the planar angle constructed from the proximal joint center, the lateral joint marker and the lateral segmental marker (i.e. skin or wand). We assessed the effect of marker misplacement and soft-tissue artefact on kinematics.

RESULTS

The averaged planar angles calculated from static ranged from 10° to 30° and 7° to 21° for the skin-mounted thigh and shank markers respectively, while planar angles were always larger than 25° with wand-mounted markers. One cm misplacement of the thigh marker altered hip rotation by 10° if skin-mounted against 5° if wand-mounted. Soft tissue artefact led to 7.6° or 4.3° depending if it was skin- or wand-mounted, respectively.

SIGNIFICANCE

Our analysis showed moderate risk of collinearity, increased effect of STA, and larger potential effect of marker misplacement with the use of skin- rather than wand-mounted markers.

Exploring the factors that influence stakeholders' expectations and subsequent perception of lower limb orthopaedic surgical outcomes for ambulant children with cerebral palsy - a qualitative study

PURPOSE

To explore the perspectives of children with CP, their parents or carers, and health professionals on factors affecting expectations and perceptions of surgical outcomes for lower limb orthopaedic surgery.

MATERIALS AND METHODS

Semi-structured interviews were conducted with 10 healthcare professionals, 10 children and young people with CP, and 8 parents. Interview data were analysed by content analysis supported by the Framework Approach using the International Classification of Functioning, Disability, and Health (ICF-CY).

RESULTS

A comprehensive list of 10 factors including facilitators, barriers, motivational and demotivational factors were identified and categorized into two overreaching themes (Environmental and Personal factors): interdisciplinary collaboration, communication and information resources, holistic care, and shared goal setting are reported as environment facilitators of outcomes expectations. In contrast, reported barriers include lack of time and resources and divergent expectations. Personal motivators include family encouragement, patient's self-determination, and previous experiences, whereas personal demotivators include fear of a new environment.

CONCLUSION

The recognition of potential factors influencing expectations and perceptions of surgical outcomes could assist clinical reasoning when planning surgical interventions for ambulant children with CP. If these factors are integrated into the healthcare practice, it will most likely enhance the positive stakeholders' experiences postoperatively.IMPLICATION FOR REHABILITATIONUnderstanding relevant stakeholders' experiences offer a positive contribution to holistic and person-centred approaches in healthcare.People with cerebral palsy and their caregivers require adequate information on surgery and post-surgical rehabilitation regime in order to reach informed decisions.Previous experiences can influence surgical expectations and subsequent perceptions of the outcome.

Three decades of gait index development: A comparative review of clinical and research gait indices

BACKGROUND

A wide variety of indices have been developed to quantify gait performance markers and associate them with their respective pathologies. Indices scores have enabled better decisions regarding patient treatments and allowed for optimized monitoring of the evolution of their condition. The extensive range of human gait indices presented over the last 30 years is evaluated and summarized in this narrative literature review exploring their application in clinical and research environments.

METHODS

The analysis will explore historical and modern gait indices, focusing on the clinical efficacy with respect to their proposed pathology, age range, and associated parameter limits. Features, methods, and clinically acceptable errors are discussed while simultaneously assessing indices advantages and disadvantages. This review analyses all indices published between 1994 and February 2021 identified using the Medline, PubMed, ScienceDirect, CINAHL, EMBASE, and Google Scholar databases.

FINDINGS

A total of 30 indices were identified as noteworthy for clinical and research purposes and another 137 works were included for discussion. The indices were divided in three major groups: observational (13), instrumented (16) and hybrid (1). The instrumented indices were further sub-divided in six groups, namely kinematic- (4), spatiotemporal- (5), kinetic- (2), kinematic- and kinetic- (2), electromyographic- (1) and Inertial Measurement Unit-based indices (2).

INTERPRETATION

This work is one of the first reviews to summarize observational and instrumented gait indices, exploring their applicability in research and clinical contexts. The aim of this review is to assist members of these communities with the selection of the proper index for the group in analysis.

Age related progression of clinical measures and gait in ambulant children and youth with bilateral cerebral palsy without a history of surgical intervention

BACKGROUND

Age related progression needs to be considered when assessing current status and treatment outcomes in cerebral palsy (CP).

RESEARCH QUESTION

What is the association between age, gait kinematics and clinical measures in children with bilateral CP?

METHOD

A retrospective database review was conducted. Subjects with bilateral CP with baseline and follow-up 3D gait analyses, but no history of intervening surgery were identified. Clinical and summary kinematic measures were examined for age related change using repeat measures correlation. Interactions with GMFCS classification and whether surgery was recommended were examined using robust linear regression. Timeseries kinematic data for baseline and most recent follow-up analyses were analysed using statistical parametric mapping.

RESULTS

180 subjects were included. 75% of participants were classified as GMFCS I or II at baseline. Mean time to follow-up was 4.89 (2.8) years (range 1-15.9 years) with a mean age of 6.4 (2.4) at baseline and 11.3 (3.4) at final follow-up. 15.5% of subjects demonstrated an improvement in GMFCS classification while GDI remained stable. Age related progression was noted across many clinical measures with moderate correlations (r ≥ 0.5) noted for reduced popliteal angle, long lever hip abduction and internal hip rotation range. In gait, there was reduced hip extension in late stance (p < 0.001), increased knee flexion in mid-stance (p < 0.001), reduced peak knee flexion in swing (p < 0.001) and increased ankle dorsiflexion in stance (p < 0.001). In the coronal plane, there was reduced hip abduction in swing (p < 0.001). In the transverse plane, increased external rotation of the knee (p < 0.001) and reduced external ankle rotation were noted in early stance and through swing (p < 0.001). There were no changes in foot progression or hip rotation.

SIGNIFICANCE

Individuals with CP show age related progression of clinical and kinematic variables. Treatment can only be deemed successful if outcomes exceed or match these age-related changes.

Outcomes of importance to children and young adults with cerebral palsy, their parents and health professionals following lower limb orthopaedic surgery: A qualitative study to inform a Core Outcome Set

Introduction

Although several outcomes are commonly measured to assess the effect of surgery for young people with cerebral palsy (CP), these are selected mainly by health professionals and researchers. Including the perspectives of a broader range of stakeholders is an essential step towards determining important outcomes for assessment. This qualitative study involves the development of a core outcome set (COS) for lower limb orthopaedic surgery for ambulant children with CP.

Objective

This study aimed to identify outcomes that matter to children and young people with CP, their parents and healthcare professionals following lower limb orthopaedic surgery.

Methods

Semi‐structured interviews were conducted with 10 healthcare professionals, 10 children and young people with CP and 8 parents. Interview data were analysed by content analysis supported by the International Classification of Functioning, Disability and Health (ICF‐CY) supplemented by thematic analysis.

Findings

Thirty‐one outcomes were identified in total, which were linked to eleven second‐level ICF‐CY categories. There were differences between stakeholder groups in preferences and expectations from surgical outcomes. Healthcare professionals and children with their parents identified 31 and 25 outcomes, respectively. Health outcomes valued by participants were lower limb alignment and symmetry, flexibility and muscle strength, mental health, fatigue, pain, function in life, mobility, participation, being independent, quality of life and adverse events. Compared to previous published trials, 10 new outcomes were revealed by this study.

Conclusion

The researchers identified outcomes that are important to all stakeholders following lower limb orthopaedic surgery for ambulant CP. Including these outcomes in future studies would promote patient‐centred care for children and young adults with CP. Findings will be used to inform an international Delphi survey and develop a COS in this field.

Patient and Public Contribution

This study was informed by an advisory group including a young adult with CP and a parent of a child with CP. This group engaged in the design of the study and the information material to support the interview (information sheet and interview topic guide).

Percutaneous hamstring lengthening in cerebral palsy: Technique and gait outcomes based on GMFCS level

BACKGROUND

Increased knee flexion at initial contact and in stance is a common problem for children with cerebral palsy. Surgical correction with percutaneous hamstring lengthening is an alternative to open hamstring lengthening; however, outcomes are less well documented, and there is concern about increasing anterior pelvic tilt. The purpose of this study was to evaluate the short-term outcomes of percutaneous hamstring lengthenings in children with cerebral palsy using comprehensive gait analysis techniques.

RESEARCH QUESTION

Does percutaneous hamstring lengthening improve knee function, and do knee and anterior pelvic tilt outcomes vary by GMFCS level?

METHODS

A convenience sample of 52 patients with both pre and post-surgical gait analyses was evaluated retrospectively for changes in gait function in terms of temporal-spatial parameters, kinematics and kinetics. Patients were divided into two GMFCS subgroups: GMFCS level I/II and III.

RESULTS

The percutaneous hamstring lengthening results in statistically significant improvements in knee function during gait with increased knee extension at initial contact (mean 32° SD 13° to mean 21° SD 11°, p = 0.000) and improved mean knee flexion in stance (mean 23° SD 12° to mean 16° SD 11°, p = 0.000) for the total study cohort. Beneficial changes were found for knee function in both GMFCS level subgroups; however, there was an increase in pelvic tilt pre to post-surgery in the GMFCS level III subgroup (mean 21° SD 8° to mean 26° SD 6°, p = 0.012) but not the GMFCS level I/II subgroup (mean 18° SD 7° to mean 20° SD 8°, p = 0.427).

SIGNIFICANCE

Percutaneous hamstring lengthening can improve knee function for all patients; however, the impact on anterior pelvic tilt varies by GMFCS level, with increasing anterior tilt for GMFCS level III only. This study highlights the importance of understanding differences in surgical outcomes by GMFCS level to better predict post-surgical function.

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.

A-GAS: A Probabilistic Approach for Generating Automated Gait Assessment Score for Cerebral Palsy Children

Gait disorders in children with cerebral palsy (CP) affect their mental, physical, economic, and social lives. Gait assessment is one of the essential steps of gait management. It has been widely used for clinical decision making and evaluation of different treatment outcomes. However, most of the present methods of gait assessment are subjective, less sensitive to small pathological changes, time-taking and need a great effort of an expert. This work proposes an automated, comprehensive gait assessment score (A-GAS) for gait disorders in CP. Kinematic data of 356 CP and 41 typically developing subjects is used to validate the performance of A-GAS. For the computation of A-GAS, instance abnormality index (AII) and abnormality index (AI) are calculated. AII quantifies gait abnormality of a gait cycle instance, while AI quantifies gait abnormality of a joint angle profile during walking. AII is calculated for all gait cycle instances by performing probabilistic and statistical analyses. Abnormality index (AI) is a weighted sum of AII, computed for each joint angle profile. A-GAS is a weighted sum of AI, calculated for a lower limb. Moreover, a graphical representation of the gait assessment report, including AII, AI, and A-GAS is generated for providing a better depiction of the assessment score. Furthermore, the work compares A-GAS with a present rating-based gait assessment scores to understand fundamental differences. Finally, A-GAS's performance is verified for a high-cost multi-camera set-up using nine joint angle profiles and a low-cost single camera set-up using three joint angle profiles. Results show no significant differences in performance of A-GAS for both the set-ups. Therefore, A-GAS for both the set-ups can be used interchangeably.

Factors associated with increased terminal swing knee flexion in cerebral palsy

BACKGROUND

Increased terminal swing knee flexion (TSKF) impacts on step length, walking efficiency and may lead to knee flexion in stance in cerebral palsy (CP). Surgical lengthening of the hamstrings is often used to address this issue, but outcomes are inconsistent. There is an established association between TSKF and functional shortening or reduced lengthening velocity of the hamstrings. However, the aetiology of increased TSKF in CP is complex and additional associated factors are not well understood. An examination of clinical and kinematic factors associated with increased TSKF may demonstrate this complexity, highlight the multifactorial nature of this feature and provide a basis for enhanced treatment decision making.

RESEARCH QUESTION

What kinematic and clinical factors are associated with TSKF in individuals with CP?.

METHODS

A retrospective database review was conducted. Individuals with bilateral CP were identified and a subset was extracted which represented the full spectrum of degree of TSKF in the database. The total dataset for analysis was n = 88. Associations between absolute clinical and kinematic data and TSKF were explored using correlation analysis, linear and multivariate regression. Time series data were examined across quartiles using statistical parametric mapping analysis of variance (SPM ANOVA).

RESULTS

Increased TSKF was associated with overall gait impairment (GDI), degree of knee flexion throughout the stride, knee extension velocity, hamstring lengthening characteristics and functional status (GMFCS). There was no relationship to walking speed or clinical measures of hamstring extensibility on clinical assessment.

SIGNIFICANCE

TSKF is associated with multiple factors which clinicians need to consider when devising treatment strategies. Caution is advised when relying on degree of TSKF to independently guide surgical decision-making.

Usability and Reliability of the Edinburgh Visual Gait Score in Children with Spastic Cerebral Palsy Using Smartphone Slow-Motion Video Technology and a Motion Analysis Application: A Pilot Study

BACKGROUND

The Edinburgh Visual Gait Score (EVGS) is a comprehensive measure of gait abnormalities in children with cerebral palsy (CP) and has good psychometric properties. However, it is cumbersome to administer and requires multiple devices to record and measure its various components. We conducted this study to determine if a smartphone video protocol could be used to improve the usability and reliability of the EVGS for daily use in a clinic setting.

METHODS

We used a handheld smartphone camera with slow-motion video technology and a motion analysis application to record and measure the EVGS of 30 ambulatory children with spastic CP. We tested the inter- and intra-rater reliability of various components of the EVGS between two observers.

RESULTS

Average age was 7 years 3 months (range 4-14 years). The mean (range) EVGS scores for the trunk, pelvis, hip, knee, ankle, and foot were 1.18 (0-3), 0.68 (0-3), 1.1 (0-4), 3.95 (1.5-7.5), 1.87 (0-4) and 4.13 (2-6.5) respectively. Total score was 12.92 (7-21.5). The mean (SD) scores for Gross Motor Function Classification System (GMFCS) levels II and III were 10.73 (3.86) and 14.96 (4.2) (p < 0.001). The intra-observer and inter-observer reliability using percentage of complete agreement was 65-98.3% and 61.7-92.5% respectively, with kappa values ranging from 0.15 to 0.87. Reliability was more for distal limb segments as compared to proximal segments.

CONCLUSION

We have described a simple and reliable method for quantitative OGA of children with CP, using smartphone video technology and motion analysis application, which can be performed by every clinician in an office setting.

LEVEL OF EVIDENCE

Level III.

Podiatrists' views and experiences of using real time clinical gait analysis in the assessment and treatment of posterior tibial tendon dysfunction

Background

Real time clinical gait analysis (RTCGA) is often incorporated as part of a general or lower limb musculoskeletal (MSK) adult patient assessment. However, it is not known if RTCGA is clinically effective as a useful outcome measure or aids in decision making. Whether there is a clinical worth in conducting RTCGA in adult MSK consultations remains controversial. The aim of this study was to provide unique insights into MSK podiatrists use and opinions of RTCGA, using Posterior Tibial Tendon Dysfunction (PTTD) as an exemplar adult condition.

Methods

A qualitative approach was employed to explore MSK podiatrists’ views and experiences of RTCGA when assessing or treating patients with PTTD. Semi-structured interviews were conducted via Skype video calls which were transcribed using an orthographic transcription method. Thematic analysis was employed to identify key meanings and report patterns within the data.

Results

Twenty nine MSK podiatrists who used RTCGA in the assessment and treatment of PTTD participated in the study. Five themes were identified as 1) RTCGA Method; 2) Working with RTCGA; 3) RTCGA uses; 4) What could aid RTCGA; 5) How RTCGA skills are acquired. This is the first known study to explore this topic of relevance to clinicians and researchers alike. Clinical observations were not only kinematic, but also included patient perceived experiences such as pain and orthotic comfort with normative kinematic reference values not perceived as important to that management goal. The most common barefoot RTCGA observations performed were the rearfoot to leg angle, medial bulge, forefoot abduction and arch integrity. However, a high amount of variation in many gait observations was noted between participants. Documentation methods also varied with a four-point scale system to grade motion and position most often employed and RTCGA was most often learnt through experience. The main barriers to performing RTCGA were clinical time and space restrictions.

Conclusion

Findings from this study have provided a view of how podiatry MSK clinicians utilise RTCGA within their practice. MSK podiatrists use RTCGA as both an outcome measure and as an aid in decision making. This implies a perceived worth in conducting RTCGA, however further work is recommended that focusses on development of a national guideline to RTCGA to be adopted.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13047-021-00482-8.

Telehealth in Pediatric Rehabilitation

Pediatric rehabilitation focuses on optimizing function and quality of life of children through a holistic and transdisciplinary patient-centered team approach. This article describes the incorporation of telehealth in pediatric rehabilitation and its growth over the past decade. It also reviews the experience of practitioners using telehealth by necessity during the 2020 COVID-19 pandemic. Evidence suggests many applications where telehealth can appropriately substitute for traditional in-person visits, and there are many potential applications of telehealth to be explored as a means to enhance connectivity of the interdisciplinary rehabilitation team and the outreach to patients in remote and underserved areas.

Outcome domains and measures after lower limb orthopaedic surgery for ambulant children with cerebral palsy: an updated scoping review

AIM

To determine the reported outcome domains and measures used to assess lower limb orthopaedic surgery of ambulant children and young people with cerebral palsy (CP) and map these outcomes to the International Classification of Functioning, Disability and Health - Children and Youth (ICF-CY) framework.

METHOD

This updated scoping review included studies published between January 2016 and July 2019 in five databases: MEDLINE, PubMed, EMBASE, CINAHL, and the Cochrane Central Register of Controlled Trials. Studies were included if participants were ambulant individuals with CP aged between 0 and 20 years who had undergone lower limb orthopaedic surgery. Health outcome domains and measures were identified and classified using the ICF-CY framework.

RESULTS

Forty-four eligible studies were identified with a total of 40 different outcome domains recorded. Among eligible studies, 44 (100%) measured body function and structural impairment and seven (16%) measured activity limitation and participation restriction. The most frequently reported outcome was gait pattern (n=37, 84%). Few studies reported adverse effects of surgery (n=13, 30%). Twenty-nine different outcome measures were identified. Patient-reported outcomes measures were used in 10 studies (23%).

INTERPRETATION

The review highlights a heterogeneity in the reported outcome domains and measures used in CP studies. The majority of the reported outcomes focus on the ICF-CY domain of body function and structure. The review also highlights a notable shift towards patient-reported outcomes in recent years. Development of a core outcome set for lower limb orthopaedic surgery would guide researchers to use more consistent and complete measurement sets.

Clinical efficacy of instrumented gait analysis: Systematic review 2020 update

BACKGROUND

This paper updates our 2011 systematic review on the clinical efficacy of three-dimensional instrumented gait analysis (3DGA).

RESEARCH QUESTION

What is the current evidence base pertaining to the clinical efficacy of 3DGA?

METHODS

We identified English language articles published from September 2009 to October 2019 reporting primary research that used typical motion analysis laboratory methods to study human walking. Five gait laboratory experts classified articles according to the highest type of efficacy they addressed: type 1 (technical), 2 (diagnostic accuracy), 2b (outcome prediction), 3-4 (diagnostic thinking and treatment), 5 (patient outcome), 6 (societal). Articles classified into type 3-4 and higher were rated for quality using LEGEND.

RESULTS

Of 2712 articles related to the efficacy of 3DGA, over 99% addressed technical (n = 313), diagnostic (n = 1466), or outcome prediction (n = 927) efficacy. Six type 3-4 studies showed that 3DGA changes treatment plans, increases clinicians' confidence in their treatment decisions, and increases agreement among clinicians. Two type 5 articles based on a randomized controlled trial demonstrated that patient outcomes improved only when 3DGA data were available and its recommendations were followed. A population-based type 5 study found that the incidence of severe crouch gait dropped from 25% to 4% following practice changes including the addition of 3DGA. The strength of evidence was mainly 3b (lesser quality prospective cohort studies) but also included stronger studies (three level 2 controlled clinical trials).

SIGNIFICANCE

Literature related to the clinical efficacy of 3DGA has grown substantially over the last decade. Thousands of articles contribute to continued improvement of data collection and interpretation, as well as understanding of gait pathology and treatment. A smaller number of studies clearly demonstrate the efficacy of 3DGA in changing and reinforcing treatment decisions, increasing clinicians' confidence in treatment planning, and increasing agreement among clinicians, as well as the potential to improve patient outcomes.

Development of a core outcome set for lower limb orthopaedic surgical interventions in ambulant children and young people with cerebral palsy: a study protocol

INTRODUCTION

Musculoskeletal deformities and gait deviations are common features in ambulatory cerebral palsy (CP). Deformity correction through lower limb orthopaedic surgery is the standard form of care aimed at improving or preserving motor function. Current research on CP care does not always take into account individual patients' expectations and needs. There is a wide range of outcome domains and outcome measures used to assess outcome from treatment. This can lead to reporting bias and make it difficult to compare and contrast studies. A core outcome set (COS) would enhance the efficiency, relevance and overall quality of CP orthopaedic surgery research. The aim of this study is to establish a standardised COS for use in evaluating lower limb orthopaedic surgery for ambulatory children and young people with CP.

METHODS/ANALYSIS

A set of outcomes domains and outcome measures will be developed as follows: (1) a qualitative evidence synthesis to identify relevant outcomes from children and young people and family perspective; (2) a scoping review to identify relevant outcomes and outcome measures; (3) qualitative research to explore the experience of key stakeholders; (4) prioritisation of outcome domains will be achieved through a two-round Delphi process with key stakeholders; (5) a final COS will be developed at a consensus meeting with representation from key stakeholder groups.

ETHICS AND DISSEMINATION

Ethical approval for this study was granted in the UK by the Oxfordshire Research Ethics Committee B (REC reference 19/SC/0357). Informed consent will be obtained from participants taking part in the qualitative research and Delphi process. Study findings will be published in an open access journal and presented at relevant national and international conferences. Charities and associations will be engaged to promote awareness of the project COS results.

TRIAL REGISTRATION NUMBER

COMET registration: 1236.

PROSPERO REGISTRATION NUMBER

CRD42018089538.

Establishing surgical indications for hamstring lengthening and femoral derotational osteotomy in ambulatory children with cerebral palsy

PURPOSE

Surgical procedures, such as medial hamstring lengthening (MHL) and femoral derotational osteotomy (FDO), can improve the gait of children with cerebral palsy (CP); however, substantial variation exists in the factors that influence the decision to perform surgery. The purpose of this study was to use expert surgeon opinion through a Delphi technique to establish consensus for indications in ambulatory children with CP.

METHODS

A 15-member panel, all established experts with at least nine years' experience in the surgical management of children with CP, was created (mean of 20.81 years' experience). All panel members also had expertise of the use of movement analysis for the assessment of gait disorders in children with CP. The group initially focused on two of the most commonly performed procedures, MHL and FDO, in an attempt to gain consensus (> 80%). This was obtained through a standardized, iterative Delphi process.

RESULTS

For MHL, a total of 59 questions were surveyed: 41 indication questions and 18 outcome questions, for which there was consensus on ten indication questions and seven outcomes. For FDO, a total of 55 questions were surveyed: 43 indication questions and 12 outcome questions, for which there was consensus on 29 indication questions and eight outcomes.

CONCLUSION

This study is the first to use an expert panel to identify best-practice indications for common surgical procedures of children with CP. The results from this study will allow for more informed evaluation of practice and form the basis for future improvement efforts to standardize surgical recommendations internationally.

LEVEL OF EVIDENCE

Level IV.

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.

Interobserver reliability in the interpretation of three-dimensional gait analysis in children with gait disorders

AIM

To assess interobserver reliability in the interpretation of three-dimensional gait analysis (3DGA) of children with gait disorders within a single institution.

METHOD

Seven experienced interpreters in our institution participated in a quality-assurance program reviewing one unique patient's 3DGA data every 3 months. Between 2014 and 2017, 15 patients' data were interpreted (14 with spastic cerebral palsy, 1 with myelodysplasia). Interpreters were asked to select 'yes', 'no', or 'indeterminate' from a list of problems and treatment recommendations. Kappa and percent agreement calculations were performed to evaluate consistency.

RESULTS

Average percentage agreement in problem identification and treatment recommendation was greater than 84 percent and 90 percent for all interpreters respectively. Average kappa for the 10 most consistently identified problems and recommended treatments were 0.69 and 0.59 respectively. Interpreter consistency was moderate or better for the most commonly performed operations at our institution (0.44-0.59). Sagittal plane abnormalities of the hip and knee had the highest consistency.

INTERPRETATION

When institutional differences in data collection and regional variations in management philosophies are removed, interobserver consistency in 3DGA interpretation is moderate to substantial for many commonly selected items. Identification of areas with poor consistency may help address underlying causes and improve data processes.

WHAT THIS PAPER ADDS

Consistency in three-dimensional gait analysis interpretation and treatment recommendation is high within a single institution. There is moderate or better consistency for most commonly identified problems and recommended treatments. Sagittal plane problem identification of the hip and knee have the highest consistency. Lower consistency is seen in areas with poor objective measures, such as dystonia and balance.

Knee joint sagittal plane movement in cerebral palsy: a comparative study of 2-dimensional markerless video and 3-dimensional gait analysis

Background and purpose - Gait analysis is indicated in children with cerebral palsy (CP) to identify and quantify gait deviations. One particularly difficult-to-treat deviation, crouch gait, can progress in adolescence and ultimately limit the ability to ambulate. An objective quantitative assessment is essential to early identify progressive gait impairments in children with CP. 3-dimensional gait analysis (3D GA) is considered the gold standard, although it is expensive, seldom available, and unnecessarily detailed for screening and follow-up. Simple video assessments are time-consuming when processed manually, but more convenient if used in conjunction with video processing algorithms; this has yet been validated in CP. We validate a 2-dimensional markerless (2D ML) assessment of knee joint flexion/extension angles of the gait cycle in children and young adults with CP. Patients and methods - 18 individuals, mean age 15 years (6.5-28), participated. 11 had bilateral, 3 unilateral, 3 dyskinetic, and 1 ataxic CP. In the Gross Motor Function Classification System, 6 were at level I, 11 at level II, and 1 at level III. We compared 2D ML, using a single video camera with computer processing, and 3D GA. Results - The 2D ML method overestimated the knee flexion/extension angle values by 3.3 to 7.0 degrees compared with 3D GA. The reliability within 2D ML and 3D GA was mostly good to excellent. Interpretation - Despite overestimating, 2D ML is a reliable and convenient tool to assess knee angles and, more importantly, to detect changes over time within a follow-up program in ambulatory children with CP.

Real time non-instrumented clinical gait analysis as part of a clinical musculoskeletal assessment in the treatment of lower limb symptoms in adults: A systematic review

BACKGROUND

The aim of this review was to evaluate and summarise the current evidence on non-computerised or non-recorded real time adult gait assessment conducted within the clinical musculoskeletal setting. It was hoped a protocol for best practice and a framework for further research could be developed from this search.

RESEARCH QUESTION

Can a protocol for best practice and a framework for further research be established from previous literature relating to non-computerised or non-recorded real time adult gait analysis in a musculoskeletal clinical setting.

METHODS

A literature review with no limitation on date of publication was conducted on the 18th February 2017.

RESULTS

The review found no significantly informative papers relating to the search SIGNIFICANCE: The lack of research on the accuracy, reliability and therefore worth of this highly recommended area of musculoskeletal assessment raises concerns over current assessment and treatment pathways. Further work to develop a method by which gait analysis can be routinely employed in musculoskeletal clinics as a diagnostic tool is required, with any new approach undertaking robust methodological testing.

Clinical Gait Evaluation of Patients with Lumbar Spine Stenosis

OBJECTIVE

The third generation Intelligent Device for Energy Expenditure and Activity (IDEEA3, MiniSun, CA) has been developed for clinical gait evaluation, and this study was designed to evaluate the accuracy and reliability of IDEEA3 for the gait measurement of lumbar spinal stenosis (LSS) patients.

METHODS

Twelve healthy volunteers were recruited to compare gait cycle, cadence, step length, velocity, and number of steps between a motion analysis system and a high-speed video camera. Twenty hospitalized LSS patients were recruited for the comparison of the five parameters between the IDEEA3 and GoPro camera. Paired t-test, intraclass correlation coefficient, concordance correlation coefficient, and Bland-Altman plots were used for the data analysis.

RESULTS

The ratios of GoPro camera results to motion analysis system results, and the ratios of IDEEA3 results to GoPro camera results were all around 1.00. All P-values of paired t-tests for gait cycle, cadence, step length, and velocity were greater than 0.05, while all the ICC and CCC results were above 0.950 with P < 0.001.

CONCLUSIONS

The measurements for gait cycle, cadence, step length, velocity, and number of steps with the GoPro camera are highly consistent with the measurements with the motion analysis system. The measurements for IDEEA3 are consistent with those for the GoPro camera. IDEEA3 can be effectively used in the gait measurement of LSS patients.

A Mechanical Sensor Designed for Dynamic Joint Angle Measurement

Background. The measurement of the functional range of motion (FROM) of lower limb joints is an essential parameter for gait analysis especially in evaluating rehabilitation programs. Aim. To develop a simple, reliable, and affordable mechanical goniometer (MGR) for gait analysis, with six-degree freedom to dynamically assess lower limb joint angles. Design. Randomized control trials, in which a new MGR was developed for the measurements of FROM of lower limb joints. Setting. Reliability of the designed MGR was evaluated and validated by a motion analysis system (MAS). Population. Thirty healthy subjects participated in this study. Methods. Reliability and validity of the new MGR were tested by intraclass correlation coefficient (ICC), Bland-Altman plots, and linear correlation analysis. Results. The MGR has good inter- and intrarater reliability and validity with ICC ≥ 0.93 (for both). Moreover, measurements made by MGR and MAS were comparable and repeatable with each other, as confirmed by Bland-Altman plots. Furthermore, a very high degree of linear correlation (R ≥ 0.92 for all joint angle measurements) was found between the lower limb joint angles measured by MGR and MAS. Conclusion. A simple, reliable, and affordable MGR has been designed and developed to aid clinical assessment and treatment evaluation of gait disorders.

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.

Correlation between transverse plan kinematics and foot progression angle in children with spastic diplegia

In diplegic patients, the orientation of foot progression depends on multiple factors. We investigated the relationship between foot progression alignment, hip and pelvic rotations during gait, femoral anteversion, and tibial torsion. Kinematic and clinical parameters were evaluated for 114 children who walked independently and had not undergone previous surgery. Causes of intoeing presented combined in 72% of cases. Internal foot progression correlated with internal hip rotation and showed an inverse correlation with tibial torsion. Our results indicate that data from clinical examination and gait analysis should be evaluated carefully before making treatment recommendations, especially in terms of the correction of torsional problems, in patients with cerebral palsy.

Reliability of 3D upper limb motion analysis in children with obstetric brachial plexus palsy

Kinematics, measured by 3D upper limb motion analysis (3D-ULMA), can potentially increase understanding of movement patterns by quantifying individual joint contributions. Reliability in children with obstetric brachial plexus palsy (OBPP) has not been established.

OBJECTIVE

This study aimed to determine between session reliability and measurement errors of 3D-ULMA using the acromion method (AM) in children with OBPP.

APPROACH

Ten participants (mean 10 years, range 7-15 years, Narakas classification I-III) completed 3D-ULMA on two occasions, mean interval of 8.6 d (±2.8 d). Kinematic data were captured by a 4-CODA cx1 optoelectronic tracking system. Participants performed three trials of the modified Mallet scale tasks. Local coordinate systems, segment and joint rotations were defined as recommended by the International Society of Biomechanics. The intraclass correlation coefficient (ICC 2,K) and standard error of measurement (SEM) were calculated for task duration, range and joint angle at point of task achievement (PTA).

MAIN RESULTS

Results indicated poor reliability for spatiotemporal parameters and range. Moderate to excellent reliability at PTA was observed in 19/60 variables (ICC: 0.77-0.98; SEM: 3.5°-10.4°). The Abduction Task had the highest (ICC: 0.79-0.98; SEM: 3.5°-10.3°) with External Rotation the lowest reliability. Glenohumeral and thoracohumeral elevation had the most consistent reliability. Scapular protraction/retraction had consistently poor reliability (ICC: 0-0.72; SEM: 3.5°-10.2°) with axial rotation also poor (ICC: 0.00-0.91; SEM: 6.3°-32.8°). This study determined inconsistent test-retest reliability of 3D-ULMA, using AM, to track dynamic performance of functional tasks in children with OBPP. It is the first study to outline measurement error in this population. This information permits more reliable interpretation of future studies of kinematic patterns in children with OBPP.

Orthopedic surgery in cerebral palsy: Instructional course lecture

Orthopedic surgery (OS) plays an important role in the management of cerebral palsy (CP). The objectives of OS are to optimize functions and prevent deformity. Newer developments in OS for CP include emphasis on hip surveillance, minimally invasive procedures, use of external fixators instead of plates and screws, better understanding of lever arm dysfunctions (that can only be corrected by bony OS), orthopedic selective spasticity-control surgery, and single-event multilevel lever arm restoration and anti spasticity surgery, which have led to significant improvements in gross motor function and ambulation, especially in spastic quadriplegia, athetosis, and dystonia. The results of OS can be dramatic and life altering for the person with CP and their caregivers if it is performed meticulously by a specialized surgical team, at the appropriate age, for the correct indications, employing sound biomechanical principles and is followed by physician-led, protocol based, intensive, multidisciplinary, institutional rehabilitation, and long term followup. However, OS can be a double-edged sword, and if performed less than optimally, and without the supporting multidisciplinary medical and rehabilitation team, expertise and infrastructure, it often leads to significant functional worsening of the person with CP, including irretrievable loss of previous ambulatory capacity. OS must be integrated into the long term management of the person with CP and should be anticipated and planned at the optimal time and not viewed as a "last resort" intervention or failure of rehabilitation. This instructional course lecture reviews the relevant contemporary principles and techniques of OS in CP.

Validity of a Wireless Gait Analysis Tool (Wi-GAT) in assessing spatio-temporal gait parameters at slow, preferred and fast walking speeds

BACKGROUND

The wireless gait assessment tool (Wi-GAT) measures have been shown to have good to excellent concurrent validity with preferred walking speeds, however, the validity of the Wi-GAT measures at slow and fast walking speeds is unknown.

OBJECTIVE

To establish validity of the Wi-GAT spatio-temporal gait measures at slow, fast, and preferred walking speeds.

METHODS

Twenty two healthy adult volunteers, with a mean age of 25.7 (± 5.3) participated in this study. The spatio-temporal gait variables of each participant were concurrently recorded using the GAITrite and the Wi-GAT system, while the participants performed 3 trials for each walking speed in a randomized order. Intraclass correlation analyses were performed to establish the agreement between the measures recorded by the GAITrite and Wi-GAT systems.

RESULTS

Walking speed measured both by the Wi-GAT and the GAITrite systems showed excellent agreement for preferred (ICC = 0.979 p< 0.001), slow (ICC = 0.989 p< 0.001) and fast (ICC = 0.967 p< 0.001) walking speeds. Most gait parameters recorded at slow walking speed showed good (ICC > 0.70) to excellent (ICC > 0.85) agreement.

CONCLUSIONS

Gait parameters recorded by the Wi-GAT system showed fair to excellent validity for preferred and slow walking speeds.

Reliability and validity of Edinburgh visual gait score as an evaluation tool for children with cerebral palsy

Assessment of gait abnormalities in cerebral palsy (CP) is challenging, and access to instrumented gait analysis is not always feasible. Therefore, many observational gait analysis scales have been devised. This study aimed to evaluate the interobserver reliability, intraobserver reliability, and validity of Edinburgh visual gait score (EVGS). Video of 30 children with spastic CP were reviewed by 7 raters (10 children each in GMFCS levels I, II, and III, age 6-12 years). Three observers had high level of experience in gait analysis (10+ years), two had medium level (2-5 years) and two had no previous experience (orthopedic fellows). Interobserver reliability was evaluated using percentage of complete agreement and kappa values. Criterion validity was evaluated by comparing EVGS scores with 3DGA data taken from the same video visit. Interobserver agreement was 60-90% and Kappa values were 0.18-0.85 for the 17 items in EVGS. Reliability was higher for distal segments (foot/ankle/knee 63-90%; trunk/pelvis/hip 60-76%), with greater experience (high 66-91%, medium 62-90%, no-experience 41-87%), with more EVGS practice (1st 10 videos 52-88%, last 10 videos 64-97%) and when used with higher functioning children (GMFCS I 65-96%, II 58-90%, III 35-65%). Intraobserver agreement was 64-92%. Agreement between EVGS and 3DGA was 52-73%. We believe that having EVGS as part of the standardized gait evaluation is helpful in optimizing the visual scoring. EVGS can be a supportive tool that adds quantitative data instead of only qualitative assessment to a video only gait evaluation.

Validation of hip joint center localization methods during gait analysis using 3D EOS imaging in typically developing and cerebral palsy children

Localization of the hip joint center (HJC) is essential in computation of gait data. EOS low dose biplanar X-rays have been shown to be a good reference in evaluating various methods of HJC localization in adults. The aim is to evaluate predictive and functional techniques for HJC localization in typically developing (TD) and cerebral palsy (CP) children, using EOS as an image based reference. Eleven TD and 17 CP children underwent 3D gait analysis. Six HJC localization methods were evaluated in each group bilaterally: 3 predictive (Plug in Gait, Bell and Harrington) and 3 functional methods based on the star arc technique (symmetrical center of rotation estimate, center transformation technique and geometrical sphere fitting). All children then underwent EOS low dose biplanar radiographs. Pelvis, lower limbs and their corresponding external markers were reconstructed in 3D. The center of the femoral head was considered as the reference (HJCEOS). Euclidean distances between HJCs estimated by each of the 6 methods and the HJCEOS were calculated; distances were shown to be lower in predictive compared to functional methods (p<0.0001). Contrarily to findings in adults, functional methods were shown to be less accurate than predictive methods in TD and CP children, which could be mainly due to the shorter thigh segment in children. Harrington method was shown to be the most accurate in the prediction of HJC (mean error≈18mm, SD=9mm) and quasi-equivalent to the Bell method. The bias for each method was quantified, allowing its correction for an improved HJC estimation.

Trunk movements during gait in cerebral palsy

BACKGROUND

Lower limb deficits have been widely studied during gait in cerebral palsy, deficits in upper body have received little attention. The purpose of this research was to describe the characteristics of trunk movement of cerebral palsy children in terms of type of deficits (diplegia/hemiplegia) and gross motor function classification system (1, 2 or 3).

METHODS

Data from 92 cerebral palsy children, which corresponds to 141 clinical gait analysis, were retrospectively selected. Kinematic parameters of trunk were extracted from thorax and spine angles in the sagittal, transverse and coronal planes. The range of motion and the mean positions over the gait cycle were analysed. Intra-group differences between the children with diplegia or hemiplegia, gross motor function classification systems 1 to 3 and typically developing participants were analysed with Kruskal-Wallis tests and post hoc tests. Pearson correlation coefficients between the gait profile score normalised walking speed and kinematic parameters of the thorax were assessed.

FINDINGS

The results revealed: 1) the range of motion of the thorax and spine exhibited more significant differences between groups than the mean positions; 2) greater levels of impairment were associated with higher thorax range of motion, and 3) the children with diplegia and gross motor function classification system 3 exhibited a greater range of motion for all planes with the exception of spine rotation.

INTERPRETATION

This study confirmed that greater levels of impairment in cerebral palsy are associated with greater thorax range of motion during gait. The thorax plays an important role during gait in cerebral palsy.

Observational gait assessment tools in paediatrics--a systematic review

Instrumented gait analysis (IGA) is an expensive technique used to objectively detect gait abnormalities in children. Observational gait assessment is considered as a cost effective alternate for IGA in regular clinical practice. This article is aimed at systematically reviewing the available paediatric gait analysis tools and examines their reliability and validity compared to IGA. This review also examines the structure of these tools, their clinical use and limitations. Articles were searched from PubMed, CINHL, AMED, BNI, EMBASE, PEDro and Cochrane library from the earliest record on the database to December 2012. Hand searches were carried out in a few journals. Studies that examined children's gait using a structured assessment tool were included and analysed for their quality, reliability and validity. Pre-established criteria were used to judge the quality of methodology and reliability and validity. Five observational gait tools for children with Cerebral Palsy (CP) and one for children with Downs Syndrome were identified. Nine studies related to children with CP were enrolled for this review. None of the tools have accomplished the level of IGA's consistency. Edinburgh Visual Gait Score (EVGS) was found to have better reliability and validity than the other tools. Very limited studies were available for most of the gait assessment tools therefore their clinical use cannot be judged based on the existing evidence. EVGS was found to have better concurrent validity and reliability and it should be considered to assess CP gait in regular practice. Future work to investigate the use of low cost technology to improve observers' accuracy of EVGS is suggested.

A novel application of musculoskeletal ultrasound imaging

Ultrasound is an attractive modality for imaging muscle and tendon motion during dynamic tasks and can provide a complementary methodological approach for biomechanical studies in a clinical or laboratory setting. Towards this goal, methods for quantification of muscle kinematics from ultrasound imagery are being developed based on image processing. The temporal resolution of these methods is typically not sufficient for highly dynamic tasks, such as drop-landing. We propose a new approach that utilizes a Doppler method for quantifying muscle kinematics. We have developed a novel vector tissue Doppler imaging (vTDI) technique that can be used to measure musculoskeletal contraction velocity, strain and strain rate with sub-millisecond temporal resolution during dynamic activities using ultrasound. The goal of this preliminary study was to investigate the repeatability and potential applicability of the vTDI technique in measuring musculoskeletal velocities during a drop-landing task, in healthy subjects. The vTDI measurements can be performed concurrently with other biomechanical techniques, such as 3D motion capture for joint kinematics and kinetics, electromyography for timing of muscle activation and force plates for ground reaction force. Integration of these complementary techniques could lead to a better understanding of dynamic muscle function and dysfunction underlying the pathogenesis and pathophysiology of musculoskeletal disorders.

Spatio-temporal gait analysis in children with cerebral palsy using, foot-worn inertial sensors

A child's natural gait pattern may be affected by the gait laboratory environment. Wearable devices using body-worn sensors have been developed for gait analysis. The purpose of this study was to validate and explore the use of foot-worn inertial sensors for the measurement of selected spatio-temporal parameters, based on the 3D foot trajectory, in independently walking children with cerebral palsy (CP). We performed a case control study with 14 children with CP aged 6-15 years old and 15 age-matched controls. Accuracy and precision of the foot-worn device were measured using an optical motion capture system as the reference system. Mean accuracy ± precision for both groups was 3.4 ± 4.6 cm for stride length, 4.3 ± 4.2 cm/s for speed and 0.5 ± 2.9° for strike angle. Longer stance and shorter swing phases with an increase in double support were observed in children with CP (p=0.001). Stride length, speed and peak angular velocity during swing were decreased in paretic limbs, with significant differences in strike and lift-off angles. Children with cerebral palsy showed significantly higher inter-stride variability (measured by their coefficient of variation) for speed, stride length, swing and stance. During turning trajectories speed and stride length decreased significantly (p<0.01) for both groups, whereas stance increased significantly (p<0.01) in CP children only. Foot-worn inertial sensors allowed us to analyze gait spatiotemporal data outside a laboratory environment with good accuracy and precision and congruent results with what is known of gait variations during linear walking in children with CP.

Management of children with ambulatory cerebral palsy: an evidence-based review. Commentary by Hugh Williamson Gait Laboratory staff

The evaluation of complex interventions, such as Single Event Multilevel Surgery (SEMLS) requires more than randomized controlled trials. Rehabilitation following SEMLS is prolonged and the outcomes of interest may not be apparent for 5 years or more after the surgery. We suggest long term, prospective cohort studies with objective outcome measures be recognized as of equal importance to randomized controlled trials. The evidence in support of instrumented gait analysis (IGA) is also reviewed. We suggest that clinical levels of evidence are not an appropriate method to evaluate a measurement tool. Specifically, IGA should be evaluated in terms of validity, reliability and cost effectiveness. We demonstrate that the use of IGA has improved medium and long term outcomes in ambulant children with cerebral palsy in a center where IGA has been used routinely both for planning SEMLS and for monitoring outcomes.

Management of children with ambulatory cerebral palsy: an evidence-based review

This article reviews the current best evidence for musculoskeletal interventions in children with ambulatory cerebral palsy (CP). The effectiveness of interventions in CP must first consider what CP and its associated pathophysiology are and take into account the heterogeneity and natural history of CP to put definitions of "effectiveness" into perspective. This article reviews the current standards of the definition and classification of CP, discusses the natural history and specific goals for the management of ambulatory CP, as well as the outcome measures available to measure these goals. The current best evidence of effectiveness is reviewed for specific interventions in children with ambulatory CP including spasticity management with botulinum toxin A injections and selective dorsal rhizotomy; multilevel orthopaedic surgery to address contractures and bony deformity; and the role of gait analysis for surgical decision-making before orthopaedic surgery.

A candidate core set of outcome measures based on the International Classification of Functioning, Disability and Health for clinical studies on lower limb orthoses

BACKGROUND

Although many core sets of measurement concepts have been published in the literature, this has not been done for the field of lower limb orthoses.

OBJECTIVES

This paper provides an overview of the measurement concepts that are relevant in lower limb orthotic evaluations, and it proposes a candidate Core Set of outcome measures to be used in clinical studies on ankle-foot orthoses (AFOs) and knee-ankle-foot orthoses (KAFOs).

STUDY DESIGN

Literature review.

METHODS

The International Classification of Functioning, Disability and Health (ICF) was used as framework to select relevant concepts.

RESULTS AND CONCLUSION

Measurement concepts covering all ICF levels of functioning were identified as relevant for the Core Set, including functions of the joints and bones (b710-b729), muscle functions (b730-b749), gait pattern functions (b770), walking (b450), moving around in different locations (d460), and daily-life functioning (d5-d9). Further validation of this candidate Core Set through a formal decision-making process is needed to obtain consensus among experts in the field. Based on such a consensus, the next step will be to systematically review the literature and identify those measurement instruments that are best suited to assess the proposed concepts, based on their psychometric properties in a given sample and context. Thereafter, we suggest that this ICF Core Set of measurement instruments should be applied in orthotic studies on AFOs and KAFOs in ambulatory patients with gait problems.

CLINICAL RELEVANCE

Although many ICF Core Sets have been published, this has not been done for the field of lower limb orthoses. We feel that such a Core Set is urgently needed, to enable comparison of results, and establish evidence on the efficacy of orthotic treatment, which will improve patient care.

Efficacy of clinical gait analysis: A systematic review

The aim of this systematic review was to evaluate and summarize the current evidence base related to the clinical efficacy of gait analysis. A literature review was conducted to identify references related to human gait analysis published between January 2000 and September 2009 plus relevant older references. The references were assessed independently by four reviewers using a hierarchical model of efficacy adapted for gait analysis, and final scores were agreed upon by at least three of the four reviewers. 1528 references were identified relating to human instrumented gait analysis. Of these, 116 original articles addressed technical accuracy efficacy, 89 addressed diagnostic accuracy efficacy, 11 addressed diagnostic thinking and treatment efficacy, seven addressed patient outcomes efficacy, and one addressed societal efficacy, with some of the articles addressing multiple levels of efficacy. This body of literature provides strong evidence for the technical, diagnostic accuracy, diagnostic thinking and treatment efficacy of gait analysis. The existing evidence also indicates efficacy at the higher levels of patient outcomes and societal cost-effectiveness, but this evidence is more sparse and does not include any randomized controlled trials. Thus, the current evidence supports the clinical efficacy of gait analysis, particularly at the lower levels of efficacy, but additional research is needed to strengthen the evidence base at the higher levels of efficacy.

Video analysis software increases the interrater reliability of video gait assessments in children with cerebral palsy

The aim of this study was to determine the effect of using video analysis software on the interrater reliability of visual assessments of gait videos in children with cerebral palsy. Two clinicians viewed the same random selection of 20 sagittal and frontal video recordings of 12 children with cerebral palsy routinely acquired during outpatient rehabilitation clinics. Both observers rated these videos in a random sequence for each lower limb using the Observational Gait Scale, once with standard video software and another with video analysis software (Dartfish(®)) which can perform angle and timing measurements. The video analysis software improved interrater agreement, measured by weighted Cohen's kappas, for the total score (κ 0.778→0.809) and all of the items that required angle and/or timing measurements (knee position mid-stance κ 0.344→0.591; hindfoot position mid-stance κ 0.160→0.346; foot contact mid-stance κ 0.700→0.854; timing of heel rise κ 0.769→0.835). The use of video analysis software is an efficient approach to improve the reliability of visual video assessments.

Level of subject-specific detail in musculoskeletal models affects hip moment arm length calculation during gait in pediatric subjects with increased femoral anteversion

Biomechanical parameters of gait such as muscle's moment arm length (MAL) and muscle-tendon length are known to be sensitive to anatomical variability. Nevertheless, most studies rely on rescaled generic models (RGMo) constructed from averaged data of cadaveric measurements in a healthy adult population. As an alternative, deformable generic models (DGMo) have been proposed. These models integrate a higher level of subject-specific detail by applying characteristic deformations to the musculoskeletal geometry. In contrast, musculoskeletal models based on magnetic resonance (MR) images (MRMo) reflect the involved subject's characteristics in every level of the model. This study investigated the effect of the varying levels of subject-specific detail in these three model types on the calculated hip MAL during gait in a pediatric population of seven cerebral palsy subjects presenting aberrant femoral geometry. Our results show large percentage differences in calculated MAL between RGMo and MRMo. Furthermore, the use of DGMo did not uniformly reduce inter-model differences in calculated MAL. The magnitude of these percentage differences stresses the need to take these effects into account when selecting the level of subject-specific detail one wants to integrate in musculoskeletal. Furthermore, the variability of these differences between subjects and between muscles makes it very difficult to a priori estimate their importance for a biomechanical analysis of a certain muscle in a given subject.

Calculating gait kinematics using MR-based kinematic models

Rescaling generic models is the most frequently applied approach in generating biomechanical models for inverse kinematics. Nevertheless it is well known that this procedure introduces errors in calculated gait kinematics due to: (1) errors associated with palpation of anatomical landmarks, (2) inaccuracies in the definition of joint coordinate systems. Based on magnetic resonance (MR) images, more accurate, subject-specific kinematic models can be built that are significantly less sensitive to both error types. We studied the difference between the two modelling techniques by quantifying differences in calculated hip and knee joint kinematics during gait. In a clinically relevant patient group of 7 pediatric cerebral palsy (CP) subjects with increased femoral anteversion, gait kinematic were calculated using (1) rescaled generic kinematic models and (2) subject-specific MR-based models. In addition, both sets of kinematics were compared to those obtained using the standard clinical data processing workflow. Inverse kinematics, calculated using rescaled generic models or the standard clinical workflow, differed largely compared to kinematics calculated using subject-specific MR-based kinematic models. The kinematic differences were most pronounced in the sagittal and transverse planes (hip and knee flexion, hip rotation). This study shows that MR-based kinematic models improve the reliability of gait kinematics, compared to generic models based on normal subjects. This is the case especially in CP subjects where bony deformations may alter the relative configuration of joint coordinate systems. Whilst high cost impedes the implementation of this modeling technique, our results demonstrate that efforts should be made to improve the level of subject-specific detail in the joint axes determination.

Challenges Facing Quantification of Rat Locomotion along Beams of Varying Widths

Optoelectronic motion capture systems have been widely used to investigate temporal gait parameters in humans and animals in order to understand function and behavioural attributes of different pathologies, e.g. Parkinson's disease (PD). The aim of the present paper was to investigate the practicality of utilising this system to investigate the effects of a unilateral 6-hydroxydopamine (6-OHDA) lesion on rat locomotion while walking on beams of varying widths (graduated, narrow, and wide). Temporal gait parameters of ten male Lister Hooded rats (five controls and five hemiparkinsonian) were observed using passive markers placed in locations that were representative of their four limbs and their body axis. The results demonstrate that marker-based motion capture can provide an effective and simple approach to quantifying temporal gait parameters for rat models of PD. They also reveal how the width of the path affects the locomotion in both experimental cohorts. Such measurements can be compared with human motion analysis to explore correlations between the animal model and human behaviour, which is an important step for translational medicine.

Reproducibility and validity of video screen measurements of gait in children with spastic cerebral palsy

PURPOSE

To determine the reproducibility and validity of video screen measurement (VSM) of sagittal plane joint angles during gait.

METHODS

17 children with spastic cerebral palsy walked on a 10m walkway. Videos were recorded and 3d-instrumented gait analysis was performed. Two investigators measured six sagittal joint/segment angles (shank, ankle, knee, hip, pelvis, and trunk) using a custom-made software package. The intra- and interrater reproducibility were expressed by the intraclass correlation coefficient (ICC), standard error of measurements (SEM) and smallest detectable difference (SDD). The agreement between VSM and 3d joint angles was illustrated by Bland-Altman plots and limits of agreement (LoA).

RESULTS

Regarding the intrarater reproducibility of VSM, the ICC ranged from 0.99 (shank) to 0.58 (trunk), the SEM from 0.81 degrees (shank) to 5.97 degrees (trunk) and the SDD from 1.80 degrees (shank) to 16.55 degrees (trunk). Regarding the interrater reproducibility, the ICC ranged from 0.99 (shank) to 0.48 (trunk), the SEM from 0.70 degrees (shank) to 6.78 degrees (trunk) and the SDD from 1.95 degrees (shank) to 18.8 degrees (trunk). The LoA between VSM and 3d data ranged from 0.4+/-13.4 degrees (knee extension stance) to 12.0+/-14.6 degrees (ankle dorsiflexion swing).

CONCLUSION

When performed by the same observer, VSM mostly allows the detection of relevant changes after an intervention. However, VSM angles differ from 3d-IGA and do not reflect the real sagittal joint position, probably due to the additional movements in the other planes.

Model to estimate hamstrings behavior in cerebral palsy patients: as a pre-surgical clinical diagnosis tool

Crouch gait is the most common motion abnormality in children with cerebral palsy (CP). This paper presents a new biomechanical model based on a simple rescaling and adjustment to CP patients who develop crouch gait by subject-specific anthropometric data. The model estimates the length of hamstrings, as the distance between the origin and insertion of the muscle, and the velocity of shortening of hamstrings by the first derivative of the length with respect to time. This model has the potential to increase the benefits of three-dimensional biomechanical models as it can discriminate between short, spastic or normal hamstrings. The main advantage of this model in clinical use is that it does not require costly magnetic resonance imaging.

Can clinical gait analysis guide the management of ambulant children with bilateral spastic cerebral palsy?

BACKGROUND

The role of clinical gait analysis in the management of ambulant children with bilateral spastic cerebral palsy (BSCP) is controversial. We hypothesized that gait analysis would allow us to differentiate between children with BSCP who would benefit from surgical intervention and those in whom surgery was not indicated.

METHODS

We reviewed the outcome in 3 groups of children with BSCP referred for treatment recommendations based on gait analysis by looking at changes in the popliteal angle (PA), Gillette Gait Index (GGI), and minimum knee flexion in single support (MKFS) on a subsequent gait analysis. We identified 15 children in whom surgical intervention was not thought to be needed (SNR group) and 15 children who had multilevel surgery recommended but not performed (SND group). We randomly selected and reviewed 15 children referred during the study period who had multilevel surgery recommended and performed following gait analysis (OP group) for comparison.

RESULTS

The initial PA, MKFS, and GGI were greater in the OP and SND groups compared with the SNR group. Popliteal angle did not change between analyses in the SNR and SND groups and decreased in the OP group (P = 0.004). Minimum knee flexion in single support remained similar between analyses in the SNR group, increased in the SND group (P < 0.0001), and decreased in the OP group (P < 0.0001). The GGI remained similar in the SNR and SND groups but decreased in the OP group (P = 0.0002). The number of children in the SND group showing an increase of more than 10% in the GGI between analyses (8/15) was greater than that in the OP group (0/15) (P = 0.0022). The PA, MKFS, and GGI contributed significantly to the treatment recommendations (P = 0.0013, P = 0.0045, P = 0.0054, respectively), which were not affected by age and Gross Motor Functional Classification System level.

CONCLUSIONS

Gait analysis helped us to distinguish children with BSCP who would benefit from surgery from those in whom nonoperative management was appropriate, and its routine clinical use is encouraged in the management of these children.

LEVEL OF EVIDENCE

Level III, retrospective comparative study.