Can on-line gait training improve clinical practice? Study protocol for feasibility randomised controlled trial of an on-line educational intervention to improve clinician's gait-related decision-making in ambulant children and young people with cerebral palsy.

BACKGROUND: Instrumented gait analysis (IGA) is an assessment and research tool with proven impacts on clinical decision-making for the management of ambulant children and young people with cerebral palsy (CYPwCP) but is underused and variably understood by relevant clinicians. Clinicians' difficulties in gaining expertise and confidence in using IGA are multifactorial and related to access for clinical decision-making, limited training opportunities and inability to translate this training into clinical practice. METHODS: The primary aim of this study is to test the feasibility of an educational intervention to advance clinicians' application of gait analysis in CYPwCP, to inform a definitive trial. The secondary aim is to measure the effect that appropriate IGA training has on physiotherapists' knowledge, skills, confidence and behaviours. This will be a two-arm feasibility randomised controlled trial with an experimental and control group. The 6-week on-line intervention uses a multicomponent approach grounded in behavioural change techniques. A repeated measures design will be adopted, whereby participants will complete outcome measures at baseline, immediately after the intervention and at 4 months. The primary outcome measures (trial feasibility-related outcomes) are recruitment and engagement. The secondary outcome measures (trial research-related outcomes) are knowledge, skills, confidence and practice change. Outcome measures will be collected via online questionnaires and during observed skill assessments. Analysis of data will use descriptive statistics, two-way mixed ANOVA model and qualitative content analysis. DISCUSSION: This study will determine feasibility of the definitive randomised control trial of educational intervention delivered to advance clinicians' application of gait analysis in CYPwCP. This study offers the shift in emphasis from regarding IGA as a tool to a focus on clinicians' requirements for access, training and a well-defined role to optimise utilisation of IGA. The impact of this should be better engagement with IGA and clinical practice change. This study will contribute to a body of educational research into clinical education of healthcare professionals and IGA training offering insight into high levels of evaluation evidence including clinical behaviour change. TRIAL REGISTRATION: Protocol has been registered with the Open Science Framework (osf.io/nweq6) in June 2023.

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.

Clinicians' Experiences of Instrumented Gait Analysis in Management of Patients with Cerebral Palsy: A Qualitative Study.

AIM: To identify the interaction of instrumented gait analysis (IGA) training, expertise, and application in gait-related management of cerebral palsy. METHODS: Semi-structured interviews with 20 purposively sampled clinicians with varying professional backgrounds, expertise, and training, analyzed using the framework method. RESULTS: Fifteen sub-themes were identified within three domains: training, equipment/outputs, and roles/reasons under the core theme IGA practice. Findings were illustrated using the Experience/Equipment/Roles/Training (Exp-ERT) Framework which identifies four user categories - based on influencing factors, beset by barriers, with experience reported as a common enabling factor. Clinicians who encountered barriers in one of the domains were categorized as either "frustrated" or "hesitant" users. Those who were no longer using IGA for clinical decisions were designated "confident non-users". Finally, the 'confident experts' reported the required level of training and access to interpret IGA outputs for clinical decision-making. Expertise gained at any level of clinical practice was shown to initiate advancement within domains. CONCLUSIONS: Clinicians encounter a multitude of barriers to IGA practice that can result in failure to progress or impact on clinical decision-making. The Exp-ERT Framework emerges strongly from the data and could serve as an evaluation tool to diagnose barriers to confident expertise and support IGA-related professional development planning.

Understanding skeletal muscle in cerebral palsy: a path to personalized medicine?

Until recently, there has been little interest in understanding the intrinsic features associated with the pathomorphology of skeletal muscle in cerebral palsy (CP). Coupled with emerging evidence that challenges the role of spasticity as a determinant of gross motor function and in the development of fixed muscle contractures, it has become increasingly important to further elucidate the underlying mechanisms responsible for muscle alterations in CP. This knowledge can help clinicians to understand and apply treatment modalities that take these aspects into account. Thus, the inherent heterogeneity of the CP phenotype allows for the potential of personalized medicine through the understanding of muscle pathomorphology on an individual basis and tailoring treatment approaches accordingly. This review aims to summarize recent developments in the understanding of CP muscle and their relationship to musculoskeletal manifestations, in addition to proposing a treatment paradigm that incorporates this new knowledge.

3D ultrasound to quantify lateral hip displacement in children with cerebral palsy: a validation study.

AIM: To assess the validity of a new index, lateral head coverage (LHC), for describing hip dysplasia in a population of children with cerebral palsy (CP). METHOD: LHC is derived from 3D ultrasound assessment. Twenty-two children (15 males, seven females; age 4-15y) with CP undergoing routine hip surveillance were recruited prospectively for the study. Each participant had both a planar radiograph acquired as part of their routine care and a 3D ultrasound assessment within 2 months. Reimer's migration percentage (RMP) and LHC were measured by the same assessor, and the correlation between them calculated using Pearson's correlation coefficient. The repeatability of LHC was investigated with three assessors, analysing each of 10 images three times. Inter- and intra-assessor variation was quantified using intraclass correlation coefficients. RESULTS: LHC was strongly correlated with RMP (Spearman's rank correlation coefficient=-0.86, p<0.001). LHC had similar inter-assessor reliability to that reported for RMP (intraclass correlation coefficient=0.97 and intra-assessor intraclass correlation coefficient=0.98). INTERPRETATION: This is an initial validation of the use of 3D ultrasound in monitoring hip development in children with CP. LHC is comparable with RMP in estimating hip dysplasia with similar levels of reliability that are reported for RMP.

Reliability and feasibility of gait initiation centre-of-pressure excursions using a Wii® Balance Board in older adults at risk of falling.

BACKGROUND: Impairments in dynamic balance have a detrimental effect in older adults at risk of falls (OARF). Gait initiation (GI) is a challenging transitional movement. Centre of pressure (COP) excursions using force plates have been used to measure GI performance. The Nintendo Wii Balance Board (WBB) offers an alternative to a standard force plate for the measurement of CoP excursion. AIMS: To determine the reliability of COP excursions using the WBB, and its feasibility within a 4-week strength and balance intervention (SBI) treating OARF. METHODS: Ten OARF subjects attending SBI and ten young healthy adults, each performed three GI trials after 10 s of quiet stance from a standardised foot position (shoulder width) before walking forward 3 m to pick up an object. Averaged COP mediolateral (ML) and anteroposterior (AP) excursions (distance) and path-length time (GI-onset to first toe-off) were analysed. RESULTS: WBB ML (0.866) and AP COP excursion (0.895) reliability (ICC3,1) was excellent, and COP path-length reliability was fair (0.517). Compared to OARF, healthy subjects presented with larger COP excursion in both directions and shorter COP path length. OARF subjects meaningfully improved their timed-up-and-go and ML COP excursion between weeks 1-4, while AP COP excursions, path length, and confidence-in-balance remained stable. DISCUSSION: COP path length and excursion directions probably measure different GI postural control attributes. Limitations in WBB accuracy and precision in transition tasks needs to be established before it can be used clinically to measure postural aspects of GI viably. CONCLUSIONS: The WBB could provide valuable clinical evaluation of balance function in OARF.

Author Correction: Reliability and feasibility of gait initiation centre-of-pressure excursions using a Wii® Balance Board in older adults at risk of falling.

In the original publication, the article title was incorrectly published as 'Reliability and feasibility of gait initiation centre-of-pressure excursions using a Wii® Balance Board in older adults at risk of failing'. The correct title should read as 'Reliability and feasibility of gait initiation centre-of-pressure excursions using a Wii® Balance Board in older adults at risk of falling'.

Selective motor control and gross motor function in bilateral spastic cerebral palsy.

AIM: To investigate the relationship between selective motor control (SMC), muscle volume, and spasticity with gross motor function in adolescents and young adults with bilateral spastic cerebral palsy (CP). METHOD: Eleven male participants with CP (mean age 15y 7mo, standard deviation 3y 6mo, range 12y 1mo-23y 1mo) in Gross Motor Function Classification System (GMFCS) levels I to IV took part in this cross-sectional study. Magnetic resonance imaging (MRI) of both lower limbs of all participants were acquired, from which 18 muscles were manually segmented and muscle volume calculated by a single assessor. Muscle volumes were normalized to body mass and averaged between limbs for each individual. SMC was assessed using Selective Control Assessment of the Lower Extremity (SCALE). Spasticity was assessed using the Modified Ashworth Scale (MAS), and gross motor functional ability was assessed using the Gross Motor Function Measure (GMFM-66). RESULTS: GMFM-66 was strongly positively correlated to SCALE (r=0.901, p≤0.001) and lower limb muscle volume normalized to body mass (r=0.750, p=0.008). MAS was significantly correlated with GMFM-66 (r=-0.691, p=0.018). INTERPRETATION: SMC is a major factor influencing gross motor function in individuals with CP. Lower limb muscle volume and spasticity also influence gross motor function. WHAT THIS PAPER ADDS: Selective motor control is a major factor of gross motor function in adolescents and young adults with bilateral cerebral palsy (CP). Gross motor function is related to muscle size and level of spasticity in adolescents and young adults with bilateral CP.

Lower limb muscle volume estimation from maximum cross-sectional area and muscle length in cerebral palsy and typically developing individuals.

BACKGROUND: Deficits in muscle volume may be a significant contributor to physical disability in young people with cerebral palsy. However, 3D measurements of muscle volume using MRI or 3D ultrasound may be difficult to make routinely in the clinic. We wished to establish whether accurate estimates of muscle volume could be made from a combination of anatomical cross-sectional area and length measurements in samples of typically developing young people and young people with bilateral cerebral palsy. METHODS: Lower limb MRI scans were obtained from the lower limbs of 21 individuals with cerebral palsy (14.7±3years, 17 male) and 23 typically developing individuals (16.8±3.3years, 16 male). The volume, length and anatomical cross-sectional area were estimated from six muscles of the left lower limb. FINDINGS: Analysis of Covariance demonstrated that the relationship between the length*cross-sectional area and volume was not significantly different depending on the subject group. Linear regression analysis demonstrated that the product of anatomical cross-sectional area and length bore a strong and significant relationship to the measured muscle volume (R2 values between 0.955 and 0.988) with low standard error of the estimates of 4.8 to 8.9%. INTERPRETATION: This study demonstrates that muscle volume may be estimated accurately in typically developing individuals and individuals with cerebral palsy by a combination of anatomical cross-sectional area and muscle length. 2D ultrasound may be a convenient method of making these measurements routinely in the clinic.

A practical clinical kinematic model for the upper limbs.

A novel clinically practical upper limb model is introduced that has been developed through clinical use in children and adults with neurological conditions to guide surgery to the elbow and wrist. This model has a minimal marker set, minimal virtual markers, and no functional joint centres to minimise the demands on the patient and duration of data collection. The model calculates forearm supination independently from the humerus segment, eliminating any errors introduced by poor modelling of the shoulder joint centre. Supination is calculated by defining the forearm segment twice, from the distal and proximal ends: first, using the ulna and radial wrist markers as a segment defining line and second using the medial and lateral elbow markers as a segment defining line. This is comparable to the clinical measurement of supination utilising a goniometer and enables a reduced marker set, with only the elbow, wrist, and hand markers to be applied when only the wrist and forearm angles are of interest. A sensitivity analysis of the calculated elbow flexion-extension angles to the position of the glenohumeral joint centre is performed on one healthy female subject, aged 20 years, during elbow flexion and a forward reaching task. A comparison of the supination angles calculated utilising the novel technique compared to the rotation between the humeral and forearm segments is also given. All angles are compared to a published kinematic model that follows the recommendations of the International Society of Biomechanics.

The relationship between lower limb muscle volume and body mass in ambulant individuals with bilateral cerebral palsy.

BACKGROUND: Individuals with cerebral palsy have smaller muscle volumes normalised to body mass than their typically developing peers. The aim of this study is to investigate the relationship between lower limb muscle volume and body mass in young people with bilateral cerebral palsy and their typically developing peers. METHODS: Twenty-five participants with bilateral cerebral palsy (aged 14.7±3.0 years, GMFCS level I-III) and 25 of their typically developing peers (aged 16.8±3.3 years) took part in this study. None of the participants had undergone orthopaedic surgery, botulinum toxin injections, or serial casting in the previous year. All participants underwent magnetic resonance imaging of both lower limbs. Nine major muscles of each lower limb were individually manually segmented and the muscle volumes calculated. RESULTS: Body mass and total lower limb muscle volume were significantly linearly related in both the cerebral palsy (R2 = 0.75, p<0.001) and typically developing (R2 = 0.77, p<0.001) groups. The slope of the relationship between muscle volume and body mass was significantly shallower in the cerebral palsy group compared to the typically developing group (p=0.007). CONCLUSIONS: This cross-sectional study suggests that the increase in size of lower limb muscles relative to body mass is reduced in adolescents and young adults with cerebral palsy. Longitudinal studies are required to further investigate altered muscle growth trajectories in this group and their impact on long-term mobility.

A device for testing the dynamic performance of in situ force plates.

Force plates are often incorporated into motion capture systems for the calculation of joint kinetic variables and other data. This project aimed to create a system that could be used to check the dynamic performance of force plate in situ. The proposed solution involved the design and development of an eccentrically loaded wheel mounted on a weighted frame. The frame was designed to hold a wheel mounted in two orthogonal positions. The wheel was placed on the force plate and spun. A VICON™ motion analysis system captured the positional data of the markers placed around the rim of the wheel which was used to create a simulated force profile, and the force profile was dependent on spin speed. The root mean square error between the simulated force profile and the force plate measurement was calculated. For nine trials conducted, the root mean square error between the two simultaneous measures of force was calculated. The difference between the force profiles in the x- and y-directions is approximately 2%. The difference in the z-direction was under 0.5%. The eccentrically loaded wheel produced a predictable centripetal force in the plane of the wheel which varied in direction as the wheel was spun and magnitude dependent on the spin speed. There are three important advantages to the eccentrically loaded wheel: (1) it does not rely on force measurements made from other devices, (2) the tests require only 15 min to complete per force plate and (3) the forces exerted on the plate are similar to those of paediatric gait.

Selective motor control correlates with gait abnormality in children with cerebral palsy.

Children with bilateral cerebral palsy (CP) commonly have limited selective motor control (SMC). This affects their ability to complete functional tasks. The impact of impaired SMC on walking has yet to be fully understood. Measures of SMC have been shown to correlate with specific characteristics of gait, however the impact of SMC on overall gait pattern has not been reported. This study explored SMC data collected as part of routine gait analysis in children with bilateral CP. As part of their clinical assessment, SMC was measured with the Selective Control Assessment of the Lower Extremities (SCALE) in 194 patients with bilateral cerebral palsy attending for clinical gait analysis at a single centre. Their summed SCALE score was compared with overall gait impairment, as measured by Gait Profile Score (GPS). Score on SCALE showed a significant negative correlation with GPS (rs=-0.603, p<0.001). Cerebral injuries in CP result in damage to the motor tracts responsible for SMC. Our results indicate that this damage is also associated with changes in the development of walking pattern in children with CP.

Gastrocnemius muscle-tendon interaction during walking in typically-developing adults and children, and in children with spastic cerebral palsy.

BACKGROUND: Our understanding of the interaction of muscle bellies and their tendons in individuals with muscle pathology is limited. Knowledge of these interactions may inform us of the effects of musculoskeletal pathologies on muscle-tendon dynamics and the subsequent neurological control strategies used in gait. Here, we investigate gastrocnemius muscle-tendon interaction in typically-developing (TD) adults and children, and in children with spastic cerebral palsy (SCP). METHODS: We recruited six TD adults (4 female; mean age: 34 yrs. (24-54)), eight TD children (5 female; mean age: 10 yrs. (6-12)) and eight independently ambulant children with SCP (5 female; mean age 9 yrs. (6-12); 3 unilaterally-affected). A combination of 3D motion capture and 2D real-time ultrasound imaging were used to compute the gastrocnemius musculo-tendinous unit (MTU) length and estimate muscle belly and tendon lengths during walking. For the TD subjects, the measurements were made for heel-toe walking and voluntary toe-walking. RESULTS: The gastrocnemius muscle bellies of children with SCP lengthened during single support (p = 0.003). In contrast, the muscle bellies of TD subjects did not demonstrate an increase in length over the period of single support under heel-toe or toe-walking conditions. CONCLUSION: We observed lengthening of the gastrocnemius muscle bellies in children with SCP during single support, a phase of the gait cycle in which the muscle is reported consistently to be active. Repeated lengthening of muscle bellies while they are active may lead to muscle damage and have implications for the natural history of gait in this group.

Intramuscular fat in ambulant young adults with bilateral spastic cerebral palsy.

BACKGROUND: It is known that individuals with bilateral spastic cerebral palsy (BSCP) have small and weak muscles. However, no studies to date have investigated intramuscular fat infiltration in this group. The objective of this study is to determine whether adults with BSCP have greater adiposity in and around their skeletal muscles than their typically developing (TD) peers as this may have significant functional and cardio-metabolic implications for this patient group. METHODS: 10 young adults with BSCP (7 male, mean age 22.5 years, Gross Motor Function Classification System (GMFCS) levels I-III), and 10 TD young adults (6 male, mean age 22.8 years) took part in this study. 11 cm sections of the left leg of all subjects were imaged using multi-echo gradient echo chemical shift imaging (mDixon). Percentage intermuscular fat (IMAT), intramuscular fat (IntraMF) and a subcutaneous fat to muscle volume ratio (SF/M) were calculated. RESULTS: IntraMF was higher with BSCP for all muscles (p = 0.001-0.013) and was significantly different between GMFCS levels (p < 0.001), with GMFCS level III having the highest IntraMF content. IMAT was also higher with BSCP p < 0.001). No significant difference was observed in SF/M between groups. CONCLUSION: Young adults with BSCP have increased intermuscular and intramuscular fat compared to their TD peers. The relationship between these findings and potential cardio-metabolic and functional sequelae are yet to be investigated.

Bone strength is related to muscle volume in ambulant individuals with bilateral spastic cerebral palsy.

OBJECTIVE: The aim of this study is to investigate how bone strength in the distal femur and proximal tibia are related to local muscle volume in ambulant individuals with bilateral spastic cerebral palsy (CP). METHODS: Twenty-seven participants with CP (mean age: 14.6±2.9years; Gross Motor Function Classification System (GMFCS) levels I-III) and twenty-two typically developing (TD) peers (mean age: 16.7±3.3years) took part in this study. Periosteal and medullary diameter in the distal femur and cortical bone cross-sectional area (CSA) and thickness (CT) in the distal femur and proximal tibia were measured along with nine lower limb muscle volumes using MRI. Additionally, the polar section modulus (Zp) and buckling ratio (BR) were calculated to estimate bone bending strength and compressional bone stability respectively in the distal femur. The relationships of all measured parameters with muscle volume, height, age, body mass, gender, and subject group were investigated using a generalized linear model (GZLM). RESULTS: In the distal femur, Zp was significantly positively related to thigh muscle volume (p=0.007), and height (p=0.026) but not significantly related to subject group (p=0.076) or body mass (p=0.098). BR was not significantly different between groups and was not related to any of the variables tested. Cortical bone CSA was significantly lower in the CP group at both the distal femur (p=0.002) and proximal tibia (p=0.009). It was also positively associated with thigh muscle volume (p<0.001) at the distal femur, and with subject height (p=0.005) at the proximal tibia. CONCLUSIONS: Bending and compressional strength of the femur, estimated from Zp and cortical bone CSA respectively, is associated with reduced thigh muscle volume. Increasing muscle volume by strength training may have a positive effect on bone mechanics in individuals with CP.

Lower limb muscle volumes in bilateral spastic cerebral palsy.

AIM: Muscle weakness is a feature of individuals with spastic cerebral palsy (SCP) but there are few reports in the literature of muscle volume in this group. This study compares muscle volumes in adolescents and young adults with SCP with those of their typically developing (TD) peers. DESIGN: Measurements of the volumes of nine major lower limb muscles in 19 independently ambulant subjects with SCP (mean age 14.2 years (sd 2.7), 11 male, GMFCS I (n=5); GMFCS II (n=14)), 19 TD subjects (mean age 16.5 years (sd 3.0), 11 male) were made using magnetic resonance imaging. RESULTS: Lower limb muscles were smaller in the SCP group (p≤0.023 in all muscles) than the TD group with the exception of the vastii (lateralis+intermedius; p=0.868) and gluteus maximus (p=0.056). Average muscle volume deficit was 27.9%. Muscle volume deficits were significantly greater for distal muscles than proximal muscles (p<0.001). CONCLUSIONS: Reduced muscle size in adolescence and the natural history of sarcopenia in adulthood may contribute to the early loss of mobility of adults with SCP.

Effectiveness of rocker sole shoes in the management of chronic low back pain: a randomized clinical trial.

STUDY DESIGN: Multicenter, assessor-blind, randomized, clinical trial. OBJECTIVE: To compare the effectiveness of rocker sole footwear to traditional flat sole footwear as part of the management for people with low back pain (LBP). SUMMARY OF BACKGROUND DATA: During the past decade, persistent advertising has claimed that footwear constructed with a rocker sole will reduce LBP. However, there is no robust evidence to support these claims. METHODS: One hundred fifteen people with chronic LBP were randomized to wear rocker sole shoes or flat sole shoes for a minimum of 2 hours each day while standing and walking. Primary outcome was the Roland Morris Disability Questionnaire (RMDQ). In addition, participants attended an exercise and education program once a week for 4 weeks and wore their assigned shoes during these sessions. Participants were assessed without their knowledge of group allocation prerandomization, and at 6 weeks, 6 months, and 1 year (main outcome point). Analysis was by intention-to-treat method. RESULTS: At 12 months, data from 44 of 58 (77.2%) of the rocker sole group and 49 of 57 (84.5%) of the flat sole group were available for analysis. In the rocker sole group, mean reduction in RMDQ was -3.1 (95% CI [confidence interval], -4.5 to -1.6), and in the flat sole group, it was -4.4 (95% CI, -5.8 to -3.1) (a greater negative value represents a greater reduction in disability). At 6 months, more people wearing flat shoes compared with those wearing rocker shoes demonstrated a minimal clinically important improvement in disability (53.2% and 31.1%, respectively; P = 0.03). Between-group differences were not significant for RMDQ or any secondary outcomes (e.g., pain) at any time. People reporting pain when standing and walking at baseline (n = 59) reported a greater reduction in RMDQ at 12 months in the flat sole group (-4.4 [95% CI, -6.0 to -2.8], n = 29) than the rocker sole group (-2.0 [95% CI, -3.6 to -0.4], n = 30) (P < 0.05). CONCLUSION: Rocker sole shoes seem to be no more beneficial than flat sole shoes in affecting disability and pain outcomes in people with chronic LBP. Flat shoes are more beneficial for LBP aggravated by standing or walking. LEVEL OF EVIDENCE: N/A.