Gait patterns in children with hemiplegic spastic cerebral palsy

Three-Dimensional Instrumented Gait Analysis for Children With Cerebral Palsy: An Evidence-Based Clinical Practice Guideline

BACKGROUND

Children with cerebral palsy (CP) who walk have complex gait patterns and deviations often requiring physical therapy (PT)/medical/surgical interventions. Walking in children with CP can be assessed with 3-dimensional instrumented gait analysis (3D-IGA) providing kinematics (joint angles), kinetics (joint moments/powers), and muscle activity.

PURPOSE

This clinical practice guideline provides PTs, physicians, and associated clinicians involved in the care of children with CP, with 7 action statements on when and how 3D-IGA can inform clinical assessments and potential interventions. It links the action statement grades with specific levels of evidence based on a critical appraisal of the literature.

CONCLUSIONS

This clinical practice guideline addresses 3D-IGA's utility to inform surgical and non-surgical interventions, to identify gait deviations among segments/joints and planes and to evaluate the effectiveness of interventions. Best practice statements provide guidance for clinicians about the preferred characteristics of 3D-IGA laboratories including instrumentation, staffing, and reporting practices.Video Abstract: Supplemental digital content available at http://links.lww.com/PPT/A524.

Case report: The gait deviation index may predict neurotherapeutic effects of FES-assisted gait training in children with cerebral palsy

Background

Children with cerebral palsy (CP) show progressive loss of ambulatory function characterized by kinematic deviations at the hip, knee, and ankle. Functional electrical stimulation (FES) can lead to more typical lower limb kinematics during walking by eliciting appropriately timed muscle contractions. FES-assisted walking interventions have shown mixed to positive results in improving lower limb kinematics through immediate correction of gait during the application of FES, or long-term, persisting effects of non-FES-assisted gait improvements following multi-week FES-assisted gait training, at the absence of stimulation, i.e., neurotherapeutic effects. It is unknown, however, if children with CP will demonstrate a neurotherapeutic response following FES-assisted gait training because of the CP population's heterogeneity in gait deviations and responses to FES. Identifying the neurotherapeutic responders is, therefore, important to optimize the training interventions to those that have higher probability of benefiting from the intervention.

Objective

The purpose of this case study was to investigate the relationship between immediate and neurotherapeutic effects of FES-assisted walking to identify responders to a FES-assisted gait training protocol.

Methods

The primary outcome was Gait Deviation Index (GDI) and secondary outcome was root mean squared error (RMSE) of the lower extremity joint angles in the sagittal plane between participants with CP and a typically developing (TD) dataset. Potential indicators were defined as immediate improvements from baseline during FES-assisted walking followed by neurotherapeutic improvements at the end of training.

Case description

Gait analysis of two adolescent female participants with spastic diplegia (Gross Motor Function Classification System level II and III) was conducted at the start and end of a 12-week FES-assisted treadmill training protocol. Participant 1 had scissoring crouch gait, while participant 2 had jump gait.

Outcomes

The GDI showed both immediate (presence of FES) and neurotherapeutic (absence of FES after training period) improvements from baseline in our two participants. Joint angle RMSE showed mixed trends between immediate and neurotherapeutic changes from baseline. The GDI warrants investigation in a larger sample to determine if it can be used to identify responders to FES-assisted gait training.

Ankle Dorsiflexor Function after Gastrocsoleus Lengthening in Children with Cerebral Palsy: A Literature Review

Background and Objectives: Ambulant children with cerebral palsy can demonstrate persistent “foot drop” after successful gastrocsoleus lengthening (GSL) surgery for equinus deformity. This may be due to inadequate strength and/or selective motor control of the ankle dorsiflexor muscles. A procedure has been developed to reduce foot drop—Tibialis Anterior Tendon Shortening (TATS), to be performed in conjunction with GSL. However, it is currently unclear how ankle dorsiflexor function changes after surgery and which children could benefit from TATS. This review summarises changes in ankle dorsiflexor function after GSL for equinus, as reported in the literature. Methods: A search was performed of the Medline, Embase and PubMed databases from 1980 to 5 March 2021. Keywords included “cerebral palsy”, “equinus deformity”, “orthopedic procedures” and “gait analysis”. The search identified 1974 studies. Thirty-three cohort studies met the inclusion criteria for this review. Results: Twenty-two studies reported improvement in swing phase ankle dorsiflexion kinematics, after GSL. There was also evidence that clinical measures of ankle dorsiflexor strength improved after surgery. Four studies reported changes in selective motor control, with mixed results across the studies. Conclusions: There is good evidence that swing phase ankle dorsiflexion improves after GSL surgery. Although, there is limited evidence that this correlates with reduced foot drop or diminished need for an ankle-foot orthosis. Future research should be prospective, randomised, include a large sample size, and should focus on identifying the optimal candidates for TATS.

Instrumented gait analysis for management of gait disorders in children with cerebral palsy: A scoping review

BACKGROUND

The use of Instrumented Gait Analysis (IGA) for the clinical management of individuals with cerebral palsy (CP) has increased in recent years. Previous systematic reviews have been completed to evaluate and summarize the evidence related to the efficacy of IGA in general. However, a focused summary of research studies on IGA for children with CP related gait disorders is needed.

RESEARCH QUESTION

The purpose of the current work was to perform a scoping review to describe and categorize the range of existing literature about IGA as applied to the clinical management of children with CP related gait disorders.

METHOD

A health sciences librarian developed a search strategy to include four key inclusion criteria of original research study, population included children with CP, study employed IGA, available in English. The available literature was organized into six study categories: reliability and validity, documentation of subgroups or model development, IGA for clinical decision making, effectiveness of treatments that depend on IGA, cost effectiveness, IGA used to evaluate the outcome of surgical, medical or rehabilitation treatment.

RESULTS

909 studies met the inclusion criteria and were placed into the six study categories. 14 % of studies were in reliability and validity, 33 % in subgroups or modeling, 2% in IGA for clinical decision making, 2% in treatments that depend on IGA, 1% in cost effectiveness, and 49 % of studies had IGA used as an outcome measure for treatment.

SIGNIFICANCE

This scoping review has documented the wide range, diversity and extent of original research studies investigating the use of IGA for the clinical management of children with CP related gait disorders. The large volume of studies provides a basis for future work to develop a CPG about the use of IGA for the clinical management of children with CP related gait disorders.

Evaluation of Multilevel Surgeries in Children With Spastic Cerebral Palsy Based on Surface Electromyography

The root mean square (RMS) of the surface electromyography (sEMG) signal can respond to neuromuscular function, which displays a positive correlation with muscle force and muscle tension under positive and passive conditions, respectively. The purpose of this study was to investigate the changes in muscle force and tension after multilevel surgical treatments, functional selective posterior rhizotomy (FSPR) and tibial anterior muscle transfer surgery, and evaluate their clinical effect in children with spastic cerebral palsy (SCP) during walking. Children with diplegia (n = 13) and hemiplegia (n = 3) with ages from 4 to 18 years participated in this study. They were requested to walk barefoot at a self-selected speed on a 15-m-long lane. The patient's joints' range of motion (ROM) and sEMG signal of six major muscles were assessed before and after the multilevel surgeries. The gait cycle was divided into seven phases, and muscle activation state can be divided into positive and passive conditions during gait cycle. For each phase, the RMS of the sEMG signal amplitude was calculated and also normalized by a linear envelope (10-ms running RMS window). The muscle tension of the gastrocnemius decreased significantly during the loading response, initial swing, and terminal swing (p < 0.05), which helped the knee joint to get the maximum extension when the heel is on the ground and made the heel land smoothly. The muscle force of the gastrocnemius increased significantly (p < 0.05) during the mid-stance, terminal stance, and pre-swing, which could generate the driving force for the human body to move forward. The muscle tension of the biceps femoris and semitendinosus decreased significantly (p < 0.05) during the terminal stance, pre-swing, and initial swing. The decreased muscle tension could relieve the burden of the knee flexion when the knee joint was passively flexed. At the terminal swing, the muscle force of the tibial anterior increased significantly (p < 0.05), which could improve the ankle dorsiflexion ability and prevent foot drop and push forward. Thus, the neuromuscular function of cerebral palsy during walking can be evaluated by the muscle activation state and the RMS of the sEMG signal, which showed that multilevel surgical treatments are feasible and effective to treat SCP.

Bilateral symmetry in leg and joint stiffness in children with spastic hemiplegic cerebral palsy during gait

Deviations are often identified at individual joints in the gait analysis of patients with cerebral palsy. Previous gait studies on hemiplegic cerebral palsy (HCP) have focused mainly on deviations of the affected side. The current study aimed to quantify and compare the joint and leg stiffness, the contributions of skeletal and muscular components, and the associated joint angles and moments of the affected and nonaffected lower limbs during level walking in children with spastic HCP. A total of 12 children with spastic HCP and 12 healthy controls walked at a self-selected speed in a gait laboratory while their kinematic and forceplate data were measured and analyzed during loading response, midstance, terminal stance, and preswing. The altered joint kinematics and kinetics in the nonaffected limb in the HCP group appeared to be mainly a compensatory strategy to minimize the bilateral asymmetry in leg stiffness during the double-limb support phase and joint stiffness during the entire stance phase. The current results suggest that therapeutic planning and decision-making for children with HCP should consider not only the mechanics of the affected side but also the control of the nonaffected side.

Gait pattern analysis and clinical subgroup identification: a retrospective observational study

To identify basic gait features and abnormal gait patterns that are common to different neurological or musculoskeletal conditions, such as cerebral stroke, Parkinsonian disorders, radiculopathy, and musculoskeletal pain.In this retrospective study, temporal-spatial, kinematic, and kinetic gait parameters were analyzed in 424 patients with hemiplegia after stroke, 205 patients with Parkinsonian disorders, 216 patients with radiculopathy, 167 patients with musculoskeletal pain, and 316 normal controls (total, 1328 subjects). We assessed differences according to the condition and used a community detection algorithm to identify subgroups within each condition. Additionally, we developed a prediction model for subgroup classification according to gait speed and maximal hip extension in the stance phase.The main findings can be summarized as follows. First, there was an asymmetric decrease of the knee/ankle flexion angles in hemiplegia and a marked reduction of the hip/knee range of motion with increased moment in Parkinsonian disorders. Second, three abnormal gait patterns, including fast gait speed with adequate maximal hip extension, fast gait speed with inadequate maximal hip extension, and slow gait speed, were found throughout the conditions examined. Third, our simple prediction model based on gait speed and maximal hip extension angle was characterized by a high degree of accuracy in predicting subgroups within a condition.Our findings suggest the existence of specific gait patterns within and across conditions. Our novel subgrouping algorithm can be employed in routine clinical settings to classify abnormal gait patterns in various neurological disorders and guide the therapeutic approach and monitoring.

Factors associated with unaffected foot deformity in unilateral cerebral palsy

The aim of this study was to assess the angular components of the affected foot associated with valgus deformity of the unaffected foot and to redefine the actual leg-length inequality in unilateral cerebral palsy. We retrospectively reviewed the medical records and radiologic images of 76 patients with unilateral cerebral palsy. Weight-bearing plain radiography of both feet of each subject was obtained. Angular measurements focused on the collapse of the longitudinal arch, hind foot valgus and forefoot abduction. Patients were divided into two groups: with and without valgus deformity of the unaffected side. Leg-length discrepancy and pelvic obliquity angle were measured Among 76 patients, 40 (52%) had valgus deformities of the unaffected side. Independent t-test revealed no significant differences in age, affected side, type of deformity on the affected side, or application of bilateral biomechanical foot orthosis between patients with or without valgus deformity of the unaffected side. Patients with valgus deformity had significantly increased voluntary ankle dorsiflexion greater than neutral on the affected side, leg-length discrepancy and lateral talocalcaneal angle (P < 0.05). Laterally measured foot angles of both feet were significantly correlated. The optimal cut-off points for predicting valgus deformity were leg-length discrepancy >10 mm or affected limb/unaffected limb-length index <0.98. Leg-length discrepancy and lateral talocalcaneal angle of the affected foot were significantly increased in patients with valgus deformity of the unaffected side. The optimal cut-off point for predicting valgus deformity of the unaffected foot would be useful in clinical practice.

Knee Recurvatum in Children With Spastic Diplegic Cerebral Palsy

BACKGROUND

The purpose of this study is to determine which factors drive patients with diplegic cerebral palsy to walk without knee recurvatum despite hyperextension of the knee on physical examination.

METHODS

A retrospective review was conducted of all data collected in the Gait Analysis Laboratory between 1999 and 2014. Patients with spastic diplegic cerebral palsy and at least 5 degrees of knee extension on clinical examination were identified for the study. After IRB approval, a total of 60 children ranging in age from 4 to 17 were included in the study. There were 27 female patients. Gross Motor Function Classification System level was distributed in the population as follows: 34 patients at Gross Motor Function Classification System level I, 18 at level II, and 8 at level III. Patients were excluded from this study if they had extrapyramidal involvement, history of selective dorsal rhizotomy or lower extremity surgery. Patient who received botulinum toxin A injections within 1 year of the study were excluded as well. Patients were divided into 2 groups: children that walked with knee hyperextension (KH) and children that walked without knee hyperextension (KF, "knee flexion"). There were 15 subjects in the KH group and 45 subjects in the KF group. Motion Laboratory evaluation included a comprehensive examination, kinematics, and kinetic analysis with a VICOM system. All data were analyzed with unpaired t test to detect differences between the 2 groups. All statistical analysis was done only for the right legs (unless the right leg did not meet the exclusion then the left leg was analyzed) to meet the statistical requirement for independence. The Pearson correlation was applied to correlate the maximum knee extension in stance with maximum ankle dorsiflexion in stance.

RESULTS

The static measurement of dorsiflexion with knee flexed showed statistically significant difference (P=0.004) with KH group having 2.3±11.6 degrees and KF group having 13.1±12.2 degrees. There was also a statistically significant difference in the static measurement of dorsiflexion with knee extended (P=0.0014) with KH group having -3.3±9.0 degrees and KF group having 5.8±9.1 degrees. Maximum dorsiflexion in stance phase also showed significant difference (P=0.0022) with the KH group having 0.1±14.0 degrees and KF group having 11.5±11.2 degrees. Maximum dorsiflexion in stance phase also showed significant difference (P<0.001) with the DH group having 0.1 (SD) 14.0 degrees and KF group having 11.5 (SD) 11.2 degrees. There were no significant differences in popliteal angle measurements or any strength measurement.

CONCLUSIONS

Our study shows that the plantar flexion knee extension couple is the major contributing factor to cause patients with passive knee hyperextension to walk in a recurvatum pattern. This would have implications of further treatment of the knee hyperextension in stance.

LEVEL OF EVIDENCE

Level III-case-control study.

Systematic review on gait classifications in children with cerebral palsy: An update

BACKGROUND

Gait classification systems (GCSs) aim to aid clinicians and researchers in categorizing the gait of pathological populations, with the intent to improve the communication between them, to support treatment planning and enable the evaluation of patients over time. Throughout the years, various GCSs have been defined for children with cerebral palsy (CP), which were first summarized in a systematic review published in 2007.

RESEARCH QUESTION

The current systematic review aimed to: a) identify GCSs that have been more recently developed, b) appraise their methodological quality and c) specify the most commonly used multiple joint gait patterns for children with CP reported in literature.

METHODS

Four databases (Medline, EMBASE, CINAHL, Web of Science) were searched until July 2017. Several forms of validity and the reliability of these studies were assessed according to the principles of the consensus-based standards for the selection of health measurement instruments checklist or criteria defined in the original review. All published GCSs were also scrutinized in order to identify multiple joint patterns that have reached a predefined level of consensus.

RESULTS

Thirty-six studies were considered in this review, 15 of them being GCSs that were not included in the original review. The validity, reliability and clinical applicability of all GCSs was reported, including 3 studies from the original review. Six multiple joint patterns for children with CP reached a consensus in literature.

CONCLUSION

Since the previous review, obvious progress has been made in the field of GCSs for CP, resulting in improved methodological quality of the majority of published GCSs. This encouraged the applicability of GCSs in clinical or research settings. The six reliable, valid and commonly used multiple joint patterns, emerging from this systematic review, may aid clinical and research applications and create a common language among healthcare providers.

Gastrocnemius operating length with ankle foot orthoses in cerebral palsy

BACKGROUND

Many individuals with cerebral palsy wear ankle foot orthoses during daily life. Orthoses influence joint motion, but how they impact muscle remains unclear. In particular, the gastrocnemius is commonly stiff in cerebral palsy. Understanding whether orthoses stretch or shorten this muscle during daily life may inform orthosis design and rehabilitation.

OBJECTIVES

This study investigated the impact of different ankle foot orthoses on gastrocnemius operating length during walking in children with cerebral palsy.

STUDY DESIGN

Case series, within subject comparison of gastrocnemius operating length while walking barefoot and with two types of ankle foot orthoses.

METHODS

We performed gait analyses for 11 children with cerebral palsy. Each child was fit with two types of orthoses: a dynamic ankle foot orthosis (Cascade dynamic ankle foot orthosis) and an adjustable dynamic response ankle foot orthosis (Ultraflex ankle foot orthosis). Musculoskeletal modeling was used to quantify gastrocnemius musculotendon operating length and velocity with each orthosis.

RESULTS

Walking with ankle foot orthoses could stretch the gastrocnemius more than barefoot walking for some individuals; however, there was significant variability between participants and orthoses. At least one type of orthosis stretched the gastrocnemius during walking for 4/6 and 3/5 of the Gross Motor Functional Classification System Level I and III participants, respectively. AFOs also reduced peak gastrocnemius lengthening velocity compared to barefoot walking for some participants, with greater reductions among the Gross Motor Functional Classification System Level III participants. Changes in gastrocnemius operating length and lengthening velocity were related to changes in ankle and knee kinematics during gait.

CONCLUSION

Ankle foot orthoses impact gastrocnemius operating length during walking and, with proper design, may assist with stretching tight muscles in daily life. Clinical relevance Determining whether ankle foot orthoses stretch tight muscles can inform future orthotic design and potentially provide a platform for integrating therapy into daily life. However, stretching tight muscles must be balanced with other goals of orthoses such as improving gait and preventing bone deformities.

Gait pattern differences in children with unilateral cerebral palsy

Children with cerebral palsy (CP) often have atypical body posture patterns and abnormal gait patterns resulting from functional strategies to compensate for primary anomalies that are directly attributable to damage to the central nervous system. Our previous study revealed two different postural patterns in children with unilateral CP: (1) a pattern with overloading of the affected body side and (2) a pattern with under-loading of the affected side. The purpose of present study was to test whether different gait patterns dependent on weight distribution between the affected and unaffected body sides could be detected in these children. The study included 45 outpatients with unilateral CP and 51 children with mild scoliosis (reference group). The examination consisted of two inter-related parts: paedobarographic measurements of the body mass distribution between the body sides and three-dimensional instrumented gait analysis. Using cluster analysis based on the Gillette Gait Index (GGI) values, three gait patterns were described: a scoliotic gait pattern and two hemiplegic gait patterns, corresponding to overloading/under-loading of the hemi-side, which are the pro-gravitational gait pattern (PGP) and the anti-gravitational gait pattern (AGP), respectively. The results of this study showed that subjects with AGP presented a higher degree of deviation from the normal gait than children with PGP. This proof that there are differences in the GGI between the AGP and PGP could be a starting point to identify kinematic differences between these gaits in a follow-up study.

Gait pattern differences between children with mild scoliosis and children with unilateral cerebral palsy

This study was conducted to investigate the effects of asymmetrical body posture alone, i.e., the effects seen in children with mild scoliosis, vs. the effects of body posture control impairment, i.e., those seen in children with unilateral cerebral palsy on gait patterns. Three-dimensional instrumented gait analysis (3DGA) was conducted in 45 children with hemiplegia and 51 children with mild scoliosis. All the children were able to walk without assistance devices. A set of 35 selected spatiotemporal gait and kinematics parameters were evaluated when subjects walked on a treadmill. A cluster analysis revealed 3 different gait patterns: a scoliotic gait pattern and 2 different hemiplegic gait patterns. The results showed that the discrepancy in gait patterns was not simply a lower limb kinematic deviation in the sagittal plane, as expected. Additional altered kinematics, such as pelvic misorientation in the coronal plane in both the stance and swing phases and inadequate stance phase hip ad/abduction, which resulted from postural pattern features, were distinguished between the 3 gait patterns. Our study provides evidence for a strong correlation between postural and gait patterns in children with unilateral cerebral palsy. Information on differences in gait patterns may be used to improve the guidelines for early therapy for children with hemiplegia before abnormal gait patterns are fully established. The gait pathology characteristic of scoliotic children is a potential new direction for treating scoliosis that complements the standard posture and walking control therapy exercises with the use of biofeedback.

Categorization of gait patterns in adults with cerebral palsy: a clustering approach

Gait patterns in adults with cerebral palsy have, to our knowledge, never been assessed. This contrasts with the large number of studies which have attempted to categorize gait patterns in children with cerebral palsy. Several methodological approaches have been developed to objectively classify gait patterns in patients with central nervous system lesions. These methods enable the identification of groups of patients with common underlying clinical problems. One method is cluster analysis, a multivariate statistical method which is used to classify an entire data set into homogeneous groups or "clusters". The aim of this study was to determine, using cluster analysis, the principal gait patterns which can be found in adults with cerebral palsy. Data from 3D motion analyses of 44 adults with cerebral palsy were included. A hierarchical cluster analysis was used to subgroup the different gait patterns based on spatiotemporal and kinematic parameters in the sagittal and frontal planes. Five clusters were identified (C1-C5) among which, 3 subgroups were determined, based on spontaneous gait speed (C1/C2: slow, C3/C4: moderate and C5: almost normal). The different clusters were related to specific kinematic parameters that can be assessed in routine clinical practice. These 5 classifications can be used to follow changes in gait patterns throughout growth and aging as well to assess the effects of different treatments (physiotherapy, surgery, botulinum toxin, etc.) on gait patterns in adults with cerebral palsy.

Sensory feedback to ankle plantar flexors is not exaggerated during gait in spastic hemiplegic children with cerebral palsy

It is still widely believed that exaggerated stretch reflexes and increased muscle tone in ankle plantar flexors contribute to reduced ankle joint movement during gait in children with cerebral palsy (CP). However, no study has directly measured stretch reflex activity during gait in these children. We investigated sensory feedback mechanisms during walking in 20 CP children and 41 control children. Stretch responses in plantar flexor muscles evoked in stance showed an age-related decline in control but not CP children. In swing the responses were abolished in control children, but significant responses were observed in 14 CP children. This was related to reduced activation of dorsiflexors in swing. Removal of sensory feedback in stance produced a drop in soleus activity of a similar size in control and CP children. Soleus activity was observed in swing to the same extent in control and CP children. Removal of sensory feedback in swing caused a larger drop in soleus activity in control children than in CP children. The lack of age-related decline in stretch reflexes and the inability to suppress reflexes in swing is likely related to lack of maturation of corticospinal control in CP children. Since soleus activity was not seen more frequently than in control children in swing and since sensory feedback did not contribute more to their soleus activity, spasticity is unlikely to contribute to foot drop and toe walking. We propose that altered central drive to the ankle muscles and increased passive muscle stiffness are the main causes of foot drop and toe walking.

Identification of gait patterns in individuals with cerebral palsy using multiple correspondence analysis

Great importance has been placed on the development of gait classification in cerebral palsy (CP) to assist clinicians. Nevertheless, gait classification is challenging within this group because the data is characterized by a high-dimensionality and a high-variability. Thus, the aim of this study was to analyze without a priori, a database of clinical gait analysis (CGA) of CP patients, using multiple correspondence analysis (MCA). A retrospective search, including biomechanical and clinical parameters was done between 2006 and 2012. One hundred and twenty two CP patients were included in this study (51 females and 71 males, mean age ± SD: 14.2 ± 7.5 years). Sixteen biomechanical spatio-temporal and kinematic parameters were included in the analysis. This data was transformed by a fuzzy window coding based on the distribution of each parameter in three modalities: low, average and high. Afterward, a MCA was used to associate parameters and to define classes. From this, seven most explicative gait parameters used to characterize gait of CP patients were identified: maximal hip extension, hip range, knee range, maximal knee flexion at initial contact, time of peak knee flexion, and maximal ankle dorsiflexion in stance phase and in swing phase. Moreover, four main profiles of CP patients have been defined from the multivariate approach: an apparent equinus gait group (the most similar of the control group with diplegic and hemiplegic patients with a GMFCS 1), a true equinus gait group (the youngest group with diplegic and some hemiplegic patients with a GMFCS 1), a crouch gait group (the oldest group with a majority of diplegic and rare hemiplegic patients with a GMFCS 2) and a jump knee gait group (the greatest level of global spasticity of the lower limbs with a majority of diplegic and rare hemiplegic patients with a GMFCS 2). Thus, this study showed the feasibility of the MCA in order to characterize and classify a large database of CP patients.

Threshold of equinus which alters biomechanical gait parameters in children

The main aim of this study was to define the threshold angle of equinus beyond which significant changes in 3D lower limb kinematics and kinetics occur in typically developing children and to describe these changes.A customized orthosis was fitted on the right ankle of 10 typically developing children and was adjusted to +10° ankle dorsiflexion, 0°, -10°, -20° plantarflexion and maximum plantarflexion. Gait was analyzed using an optoelectronic system. A gait velocity of 1m/s was imposed.Most of the kinematic and kinetic changes were significantly altered from the -10° condition. In the sagittal plane, the results showed increased knee flexion at initial contact, increased knee flexion or hyperextension in stance, increased hip flexion at initial contact and increased anterior pelvic tilt. Other changes included increased knee varus, reduced hip adduction and more internal foot progression. The ankle plantarflexion moment was bi-phasic during stance, peak ankle power generation was reduced, peak knee extension moment was decreased and hip extension moments increased. On the contralateral side, there was a significant increase in ankle plantarflexion at initial contact and a significant decrease in knee flexion during swing phaseat maximum plantarflexion.Although slight modifications occurred for smaller degrees of equinus, the results suggest that significant kinematic and kinetic changes occurred during gait in both limbs from 10° of plantarflexion. The results of this study also provide some indications regarding the primary causes of gait deviations and secondary compensatory strategiesin children with a clinical dorsiflexion limitation.

The effect of tuning ankle foot orthoses-footwear combination on the gait parameters of children with cerebral palsy

BACKGROUND

There are a wide variety of ankle foot orthoses used in clinical practice which are characterised by their design, the material used and the stiffness of that material. Changing any of these three components will alter the effect of the ankle foot orthosis on gait.

OBJECTIVES

The purpose of this article is to provide an overview on the available research on ankle foot orthosis-footwear combination tuning on the gait characteristics of children with cerebral palsy through a structured review.

STUDY DESIGN

Literature review.

METHODS

A thorough search of previous studies published in English was conducted within all major databases using relevant phrases without any limits for the dates. These searches were then supplemented by tracking all key references from the appropriate articles identified including hand searching of published books where relevant.

RESULTS

To date, there are 947 papers in the literature pertaining to the study of ankle foot orthosis. Of these, 153 investigated the use of ankle foot orthosis for children with cerebral palsy. All the studies included in this review were of a within-subjects design and the evidence levels were generally low.

CONCLUSIONS

The overall results suggested that ankle foot orthosis-footwear combination tuning has the potential to improve the kinematics and kinetics of gait in children with cerebral palsy. However, the review highlights a lack of well-designed and adequately powered studies. Clinical relevance While the research described in this article indicates an improvement in the gait of children with cerebral palsy following tuning of their ankle foot orthosis-footwear combination, there is still a paucity of research with quantitative data on the effects of kinematics and kinetics of ankle foot orthosis-footwear combination tuning, comparing untuned ankle foot orthosis-footwear combinations with tuned ankle foot orthosis-footwear combination. Furthermore, current research does not identify the effect of tuning on energy efficiency.

Abnormalities in the uninvolved foot in children with spastic hemiplegia

BACKGROUND

Although the uninvolved foot in patients with hemiplegia has been thought to be normal, we frequently observed valgus deformity of the uninvolved foot among those patients. The purpose of this study was to evaluate by dynamic pedobarograph the prevalence and pattern of foot deformity in the uninvolved limb among children with hemiplegia.

METHODS

In this study, we included 119 patients with hemiplegia (67 males and 52 females) who underwent gait analysis from 2001 to 2008. The mean age at evaluation was 9.2 ± 3.4 years (range, 5.1 to 19.8 y). Patient demographics, passive range of motion, kinematics, kinetics, and dynamic pedobarographic data were obtained from the medical records. Coronal index [(CI): the impulse percentage under the medial column minus the impulse percentage under the lateral column] was calculated from the pedobarographic data.

RESULTS

Of 119 feet, 60 feet (50.4%) had a normal CI, whereas 52 feet (43.7%) showed a valgus CI. Only 7 feet (5.9%) had a varus CI. Compared with the patients with a normal CI, patients who had a valgus CI had increased ankle dorsiflexion at initial contact (-0.9 ± 4.1 vs. 0.8 ± 4.7, P=0.048) and knee extension moment (0.6 ± 0.31 vs. 0.73 ± 0.28, P=0.036) of the uninvolved foot. Actual limb-length discrepancy did not differ between the 2 groups (P=0.556).

CONCLUSIONS

Valgus foot deformity of the uninvolved foot is common among children with hemiplegia. It is associated with increased ankle dorsiflexion and knee extension moments of the uninvolved side. Longer follow-up will be needed to evaluate the effect of the valgus foot deformity of the uninvolved limb on the gait in patients with hemiplegia.

LEVEL OF EVIDENCE

Level III. Diagnostic.

Tibialis anterior tendon shortening in combination with Achilles tendon lengthening in spastic equinus in cerebral palsy

Equinus is the commonest deformity in cerebral palsy (CP). Many different surgical procedures have been described for the treatment of spastic equinus. In long standing equinus deformities the tibialis anterior muscle becomes elongated which is one reason for muscle weakness. Surgical tendon shortening of the tibialis anterior tendon was therefore introduced to rebalance muscle strength. All patients with CP who had a tibialis anterior tendon shortening (TATS) in combination with a tendo Achilles lengthening (TAL) were included in this study. A total of 29 patients had 30 surgical interventions (21 hemiplegic patients: 14 boys/7 girls, age 9-22 years; mean 15.2 years; 5 diplegics and 3 quadriplegics; 5 boys/3 girls, age 7-37.5 years; mean 14.8 years). Fifteen patients had additional surgery (soft tissue or bony procedures). The TATS was performed at the distal insertion with transosseous tendon fixation in the medial cuneiform bone at the original place. Movement Analysis Profile (MAP) for ankle dorsi-/plantarflexion, Gait Profile Score (GPS), Gait Deviation Index (GDI), and Gillette Gait Index (GGI) improved significantly for all patients compared pre- to postoperatively. In 93% of the patients active dorsiflexion of the ankle was possible postoperatively. We conclude that TATS in combination with TAL in spastic equinus in CP is a safe procedure and improves but not completely corrects foot positioning during gait. For the treatment of spastic equinus in CP we recommend shortening of the elongated antagonist (TATS) in combination with lengthening of the short agonist (TAL) for achieving optimal postoperative function.

The importance of being earnest about shank and thigh kinematics especially when using ankle-foot orthoses

This paper reviews and summarizes the evidence for important observations of normal and pathological gait and presents an approach to rehabilitation and orthotic management, which is based on the significance of shank and thigh kinematics for standing and gait. It discusses normal gait biomechanics, challenging some traditional beliefs, the interrelationship between segment kinematics, joint kinematics and kinetics and their relationship to orthotic design, alignment and tuning. It proposes a description of four rather than three rockers in gait; a simple categorization of pathological gait based on shank kinematics abnormality; an algorithm for the designing, aligning and tuning of AFO-Footwear Combinations; and an algorithm for determining the sagittal angle of the ankle in an AFO. It reports the results of research on Shank to Vertical Angle alignment of tuned AFO-Footwear Combinations and on the use of 'point loading' rocker soles.

Genu recurvatum in cerebral palsy--part A: influence of dynamic and fixed equinus deformity on the timing of knee recurvatum in children with cerebral palsy

The aim of the study was to confirm the hypothesis of the influence of the dynamic and fixed equinus deformity on the timing of knee recurvation (hyperextension). According to our hypothesis, dynamic equinus is linked to early and fixed equinus and to late knee hyperextension. A group 35 children with cerebral palsy (47 lower limbs) was divided into two subgroups according to the timing of maximum knee hyperextension. Clinical examination confirmed our hypothesis. Gait analysis and musculoskeletal modelling results were compared with 12 normally developing children. Both recurvatum groups had forefoot landing and neither achieved normal ankle dorsiflexion. Electromyographic examination revealed an abnormally high soleus activity in a single stance. Muscle length changes of medial gastrocnemius and soleus were in agreement with our hypothesis. Such a finding might simplify the decision as to which treatment to select for equinus deformity, present in patients with genu recurvatum.

Further evidence of validity of the Gait Deviation Index

In this paper, the relationship of the Gait Deviation Index (GDI) to gross motor function and its ability to distinguish between different Gross Motor Function Classification System (GMFCS) levels was determined. A representative sample of 184 ambulant children with CP in GMFCS levels I (n=57), II (n=91), III (n=22) and IV (n=14) were recruited as part of a population-based study. Representative gait cycles were selected following a 3D gait analysis and gross motor function was assessed using the Gross Motor Function Measure (GMFM). GDI scores were calculated in Matlab. Valid 3D kinematic data were obtained for 173 participants and both kinematic and GMFM data were obtained for 150 participants. A substantial relationship between mean GDI and GMFM-66 scores was demonstrated (r=0.70; p<0.001) with significant differences in mean GDI scores between GMFCS levels (p<0.001) indicating increasing levels of gait deviation in subjects less functionally able. The relationship between the GDI, GMFM and GMFCS in a representative sample of ambulators, lends further weight to the validity of the GDI scoring system. Furthermore it suggests that the subtleties of gait may not be wholly accounted for by gross motor function evaluation alone. Gait specific tools such as the GDI more likely capture both the functional and aesthetic components of walking.

Determination of gait patterns in children with spastic diplegic cerebral palsy using principal components

This study developed an objective graphical classification method of spastic diplegic cerebral palsy (CP) gait patterns based on principal component analysis (PCA). Gait analyses of 20 healthy and 20 spastic diplegic CP children were examined to define gait characteristics. PCA was used to reduce the dimensionality of 27 parameters (26 selected kinematics variables and age of the children) for the 40 subjects in order to identify the dominant variability in the data. Fuzzy C-mean cluster analysis was performed plotting the first three principal components, which accounted for 61% of the total variability. Results indicated that only the healthy children formed a distinct cluster; however it was possible to recognise gait patterns in overlapping clusters in children with spastic diplegia. This study demonstrates that it is possible to quantitatively classify gait types in CP using PCA. Graphical classification of gait types could assist in clinical evaluation of the children and serve as a validation of clinical reports as well as aid treatment planning.

The validity of an existing gait classification system when applied to a representative population of children with hemiplegia

This study describes sagittal plane gait patterns in a representative sample of children with hemiplegic cerebral palsy (CP). Ninety-four children were prospectively recruited to the study (age range 5-18 yrs, mean age 10 yrs 7 mo) and valid kinematic data was captured for 91 participants. Data was also captured for 49 children (age range 5-18 yrs, mean age 10 yrs) with no physical impairment. One representative gait cycle from each child was exported to an Excel template and run through an algorithm that facilitated the description of gait, using logical arguments derived from Winters' Classification. Children with hemiplegic CP, regardless of past surgery history, were allocated to the following gait types: Groups IV (n=9; 10%), III (n=7: 8%), II (n=5: 5%), I (n=32: 35%) and not classified (n=38: 42%). For children with no lower limb surgical history (n=61), gait types were: Groups IV (n=7: 12%), III (n=2: 3%), II (n=2: 3%), I (n=20: 33%) and not classified (n=30: 49%). The gait data taken from children with no physical impairment were not classified. The ability of the Winters' classification system to distinguish between children with higher levels of hemiplegic involvement and children with no physical impairment was demonstrated: the majority of children with hemiplegic CP present with relatively minor gait deviations. A more complete definition of sagittal plane ankle joint kinematics may account for those children that were not classified.

Power generation in children with spastic hemiplegic cerebral palsy

BACKGROUND

Spastic hemiplegic cerebral palsy is a challenging disorder often affecting children with high functional and cognitive level, who are good candidates for physiotherapy treatment, including co-ordination and muscle strengthening exercises. The goal of this study was to investigate hip and ankle power generation on both the hemiplegic and uninvolved sides in children with spastic hemiplegic cerebral palsy and no previous surgery.

METHODS

Ninety-nine patients with spastic hemiplegic CP with a mean age of 8.4 years were included. Medical records and gait analysis data were reviewed. Patients were classified using Winter's criteria and an independent sample t-test was used to compare groups.

RESULTS

The hip extensor power generation was higher in all Winter classification groups on both the hemiplegic and uninvolved sides, compared to age matched normal subjects. Comparing the power generation at the ankle, all groups had less power generation on both the hemiplegic and non-involved side.

CONCLUSIONS

We found a major power generation shift from the ankle to the hips in children with spastic hemiplegic cerebral palsy both on the hemiplegic and the uninvolved sides. This could be interpreted, as a way of compensating for decreased ankle power generation on the hemiplegic side. The results may suggest that muscle strengthening physiotherapy should be directed toward the hip power generators and co-ordination exercises should be focused distally to the knee and ankle. This may also suggest that power loss at the ankle, such as after tendon-Achilles lengthening, may be of less importance.

Classification of spastic hemiplegic cerebral palsy in children

BACKGROUND

The Winter classification of spastic hemiplegic cerebral palsy (CP) is based on sagittal kinematic data from 3-dimensional gait analysis used in preoperative decision making and postoperative evaluation. Our goal was to investigate how well children with spastic hemiplegic CP can be classified using Winter criteria. Second, we assessed if patients move between groups over time and/or with surgical intervention.

METHODS

One hundred twelve patients with spastic hemiplegic CP with a mean age of 8.1 years were included. Medical records and the full gait analysis data were reviewed. Patients were classified using Winter criteria, and an independent sample t test was used to compare groups.

RESULTS

We found 26 patients (23%) that could not be classified according to Winter criteria. We defined these patients as group 0. This group showed the least deviation from normal values. Each of the 5 groups in our study showed a higher mean velocity of gait and were younger than any of the groups from the Winter study. In regard to rotational alignment, kinetic variables, and, to a certain extent, muscle tone, group 0 showed the least deviation from normal values; however, most differences were subtle. When reclassifying patients after a mean of 3 years, 8 of 15 had deteriorated in the nonsurgical group, moving to a higher numbered group, whereas 19 of 31 surgically treated patients had improved.

CONCLUSIONS

The Winter classification failed to classify 23% (26/112) of our spastic hemiplegic CP children. We suggest that the classification be complemented with the less involved group 0. In this way, all patients can be classified, and thus, treatment plans can be established for all patients. The classification can be divided into ankle, knee, and hip joint involvement. The ankle involvement can be further divided into 3 separate groups. Treating physicians should be aware of the possibility that patients may move into another classification group over time.

LEVEL OF EVIDENCE

Diagnostic level 4. See instructions to authors for a complete description of levels of evidence.

An electromyographic analysis of obligatory (hemiplegic cerebral palsy) and voluntary (normal) unilateral toe-walking

This study compares lower extremity muscle activation during gait in patients with hemiplegic cerebral palsy (CP) with healthy subjects mimicking the patients. The purpose was to understand the differences between obligatory toe-walking as observed in hemiplegic CP gait and voluntary toe-walking. The results contribute to a better understanding by distinguishing between primary deviations in muscle activity as a direct consequence of the underlying neurological pathology of hemiplegic CP and secondary, compensatory deviations due to the biomechanics of toe-walking. Surface electromyographic (EMG), kinematic and kinetic data were compared between a group of 12 hemiplegic CP patients and a group of 10 healthy subjects walking normally and when mimicking hemiplegic gait. Integrated 3D gait analysis was performed with simultaneous EMG recordings of the medial gastrocnemius, tibialis anterior, rectus femoris, and semitendinosus muscles bilaterally. The EMG pattern of the toe-walking leg in the mimicking subjects was modified in gastrocnemius and tibialis anterior as compared with normal gait. This modified muscle activation pattern showed strong similarities to that of the patients and therefore can be regarded, at least in part, as activity required for toe-walking. A possible primary gait abnormality was observed in the rectus femoris where the patients showed a burst of EMG activity in mid-swing phase in contrast to the mimicking subjects who showed normal EMG during this phase.

Lower extremity kinetics for balance control in children with cerebral palsy

The authors examined and compared the effect of support-surface perturbations of various magnitudes on lower extremity kinetics of 7 children with cerebral palsy (CP) and 8 typically developing (TD) children. Results showed that the highest velocity tolerated without stepping was slower in children with CP than in either age-matched TD or younger TD children. Multimodal torque profiles were more frequent in children with CP than in TD controls. TD groups temporally and spatially organized torque activation, whereas children with CP activated all joints simultaneously and showed altered torque contribution patterns among joints. Those results suggest that impairments in reactive postural control in children with CP result not only from developmental delay but also from pathology. Evidence for pathology included increased numbers of torque bursts required to regain stability and less efficient temporal and spatial organization of torque activation patterns.

Cluster analysis for the extraction of sagittal gait patterns in children with cerebral palsy

Classification of gait disorders would facilitate standardisation of gait management and communication across professional boundaries. In the past, such classification was undertaken using a variety of approaches with often unclear methodology and validation procedures. This study describes the application of hierarchical cluster analysis on sagittal kinematic gait data derived from 56 children with cerebral palsy and 11 neurologically intact children in order to define existing clusters of gait patterns in the children's data. A structured rationale was developed to seek and validate the optimal number of homogenous gait types within the data resulting in 13 different gait clusters that were organised into 'crouch gait type', 'equinus gait type' and 'other gait type'. Applying cluster analysis in combination with visual assessment of gait data and a structured protocol, we have been able to define valid gait groupings.

Gait classification in children with cerebral palsy: a systematic review

This systematic review of the literature evaluates the validity of existing classifications of gait deviations in children with cerebral palsy (CP). Numerous efforts have been made to develop classification systems for gait in CP to assist in diagnosis, clinical decision-making and communication. The internal and external validity of gait classifications in 18 studies were examined, including their sampling methods, content validity, construct validity, reliability and clinical utility. Half of the studies used qualitative pattern recognition to construct the gait classification and the remainder used statistical techniques such as cluster analysis. Few adequately defined their samples or sampling methods. Most classifications were constructed using only sagittal plane gait data. Many did not provide adequate guidelines or evidence of reliability and validity of the classification system. No single classification addressed the full magnitude or range of gait deviations in children with CP. Although gait classification in CP can be useful in clinical and research settings, the methodological limitations of many classifications restrict their clinical and research applicability.

Gait analysis methods in rehabilitation

INTRODUCTION

Brand's four reasons for clinical tests and his analysis of the characteristics of valid biomechanical tests for use in orthopaedics are taken as a basis for determining what methodologies are required for gait analysis in a clinical rehabilitation context.

MEASUREMENT METHODS IN CLINICAL GAIT ANALYSIS

The state of the art of optical systems capable of measuring the positions of retro-reflective markers placed on the skin is sufficiently advanced that they are probably no longer a significant source of error in clinical gait analysis. Determining the anthropometry of the subject and compensating for soft tissue movement in relation to the under-lying bones are now the principal problems. Techniques for using functional tests to determine joint centres and axes of rotation are starting to be used successfully. Probably the last great challenge for optical systems is in using computational techniques to compensate for soft tissue measurements. In the long term future it is possible that direct imaging of bones and joints in three dimensions (using MRI or fluoroscopy) may replace marker based systems.

METHODS FOR INTERPRETING GAIT ANALYSIS DATA

There is still not an accepted general theory of why we walk the way we do. In the absence of this, many explanations of walking address the mechanisms by which specific movements are achieved by particular muscles. A whole new methodology is developing to determine the functions of individual muscles. This needs further development and validation. A particular requirement is for subject specific models incorporating 3-dimensional imaging data of the musculo-skeletal anatomy with kinematic and kinetic data.

METHODS FOR UNDERSTANDING THE EFFECTS OF INTERVENTION

Clinical gait analysis is extremely limited if it does not allow clinicians to choose between alternative possible interventions or to predict outcomes. This can be achieved either by rigorously planned clinical trials or using theoretical models. The evidence base is generally poor partly because of the limited number of prospective clinical trials that have been completed and more such studies are essential. Very recent work has started to show the potential of using models of the mechanisms by which people with pathology walk in order to simulate different potential interventions. The development of these models offers considerable promise for new clinical applications of gait analysis.

Electromyographic evaluation of the sound and involved side during gait of spastic hemiplegic children with cerebral palsy

The purpose of this study was to investigate the surface electromyogram (EMG) of the lower limbs of hemiplegic children with spastic cerebral palsy during gait. The EMG of seven muscles was analyzed for 17 children (5-12 years old). The EMG of the involved side was decreased for the examined shank muscles and increased for the hamstrings, during certain phases of the gait cycle, compared with the sound side. The rectus femoris of the involved side showed prolonged activation during the swing phase. The enhanced activation of the hamstrings may be beneficial/compensatory, preventing knee hyperextension. The presence of equinus foot obstructs the foot clearance and hence the prolonged rectus femoris EMG activity during the swing phase may contribute to shorten the lower limb by flexing the hip. Possible compensatory mechanisms of the proximal muscles of the involved lower limb that can be measured with instrumented gait analysis should be taken into account before the decision for a specific treatment.

Secondary gait compensations in individuals without neuromuscular involvement following a unilateral imposed equinus constraint

Ankle equinus is the most commonly identified impairment of individuals with spastic hemiplegia (SH). However, it is not clear how equinus at the ankle may contribute to gait deviations at other joints. The purpose of this study was to determine what compensatory gait deviations may occur as a result of an imposed, unilateral equinus constraint. Gait data were collected on 12 adult subjects with and without one ankle constrained in equinus using a unique taping method. Knee extension at initial contact, knee extension in mid stance, and hip extension at terminal stance were all found to be significantly reduced on the ipsilateral side as a result of the ankle constraint. On the unconstrained or contralateral side, subjects tended to adopt a foot-flat or toe-first initial contact pattern. This study suggests that stance phase limitations in both hip and knee extension in the gait of persons with hemiplegia are not necessarily caused by limited length of the involved side hamstrings and/or hip flexors, but rather that they can occur as the result of an ankle plantarflexor contracture alone. Deviations in the contralateral foot contact pattern can also occur secondary to unilateral equinus and should not be assumed to represent bilateral involvement.

Der Stellenwert der instrumentellen Ganganalyse bei der infantilen Zerebralparese

The technique of instrumented gait analysis enables the physician to exactly document spastic gait disorders. Time-distance parameters, joint kinematics and kinetics, dynamic EMG recordings and the measurement of energy consumption provide an extensive insight into gait problems. This method is used not only for diagnostic purposes but also to monitor the effects of therapeutic interventions. A significant limitation is the specialist knowledge necessary to interpret the data. For an adequate assessment, the gait data must be supplemented by clinical and radiological findings. When interpreting gait analysis reports, technical errors must always be born in mind. The subjectivity of individual interpretation is the major reason for the considerable variability in the treatment recommendations for similar patients.

Détermination d’un seuil de pression plantaire attendu : utilisation de l’approche adimensionnelle pour réduire la variabilité des pressions plantaires

OBJECTIVE

The aim of this study was to verify that the determination of walking velocities proportional to the leg lengths of the subjects together with the dimensionless expression of the results enable us to decrease the variability and to determine a plantar pressure threshold.

MATERIALS AND METHODS

Fifteen male subjects performed two walking tests on a treadmill at imposed velocities (V1 and V3) and similar velocities (V27 and V37). Similar velocities (Vsim =Nfr(g.Li)(0.5)) were determined from two fractions of the Froude number (Nfr), the gravitational acceleration (g) and the length of the lower limb (Li) of the subjects. An in-shoe plantar pressure measurement system allowed the pressure peaks to be recorded. The peak of pressure (p) was reported to the step length (a) and the weight of the subject (mg) for the dimensionless pressure peaks (Dim(P)=p.a2/mg) to be expressed. The coefficients of variability (CoV) and extends of the dimensionless pressure peaks (Epp) have been studied at the different imposed walking velocities.

RESULTS

The CoV and Epp of the dimensionless pressure peaks recorded at V27 and V37 (similar velocities) are from 2 to 9% and 3 to 22% lower than those observed at V1 and V3, respectively.

DISCUSSION-CONCLUSION

The analysis of the pressure peaks CoV and Epp shows that the method should allow a data bank usable to detect the effects of a disability on the plantar pressures to be elaborated. Indeed, our results enable us to define a plantar pressure pattern with a variability lower than those reported in most scientific articles.

Measurement of plantar pressure distribution in hemiplegic children: changes to adaptative gait patterns in accordance with deficiency

OBJECTIVE

A comparison of plantar pressure distribution in hemiplegic children with a healthy control group was performed to illustrate the link between the changing dynamics during the stance phase and the degree of deficiency.

DESIGN

Twenty three healthy control subjects and two groups of six hemiplegic children with minor and major spasticity were tested.

BACKGROUND

In previous studies, it was shown that the musculoskeletal dysfunction due to spasticity disturbed the hemiplegic gait pattern, for example reduced walking speed and step length. However, plantar pressure measurements which would help to understand the pathological gait mechanisms have not been studied.

METHODS

The stance phase parameters measured included spatio-temporal data and the relative impulse measurements during consecutive gait cycles. The relative impulses under eight plantar areas were determined with an in-shoe plantar pressure measurement device.

RESULTS

Each group had a specific plantar pressure distribution profile that varied with the degree of deficiency. The most significant differences were found beneath the midfoot, the first metatarsal head and the hallux.

CONCLUSION

The neuromuscular disorders and foot deformities due to the cerebral lesion modified the contact of the foot with the ground, and led to specific plantar pressure distribution profiles. The equinovarus, with clawed-toe deformity due to greater spasticity, seemed to be an important factor in disturbances of the terminal stance phase. However, the spastic hemiplegic subjects seemed to adopt a gait pattern required for optimal stability.

RELEVANCE

From previous work, comparable data were available only for the hemiparetic adult patients. In-shoe pressure data from spastic hemiplegic children can provide detailed information specific to each region of contact for the support of diagnosis, a clinical decision or the prescription of appropriate footwear, braces or othoses. Both peak pressure and local impulse have proven to be valuable for the understanding of foot function, lower extremity dysfunctions and walking strategies.

[Spasticity and dynamic plantar pressure distribution measurements in hemiplegic spastic children]

OBJECTIVE

The aim of this study was to analyse the plantar pressure distribution in nine hemiplegic spastic children to illustrate the dynamic alteration during stance phase linked spasticity grade.

MATERIAL AND METHODS

The graduation of the lower limbs muscle tone related to the Aschworth spasticity scale enabled us to identify two groups of hemiplegics subjects. The groups Asch 1 and Asch 3 have respectively presented a low and a strong spasticity. The peak pressures during consecutive gait cycles were determined under the feet of 30 healthy subjects and two cerebral palsy groups using a wearable footprint analysis system.

RESULTS

A statistical study showed a similarity between the two disabled groups. Peak pressures under the midfoot were significantly higher compared to the control group. While the plantar pressure distribution profile was specific for each group under all other anatomical structures. The significant alterations were observed under the forefoot and hallux.

DISCUSSION-CONCLUSION

Spasticity modifies the foot contact to ground and leads to a specific plantar pressure distribution profile linked to the spasticity grade. The equinovarus with clawed toes deformity due to higher spasticity seems to be an important factor in terminal stance phase perturbations. However spastic hemiplegic subjects seem to adopt a gait pattern in agreement with stability optimization criteria.

Common abnormal kinetic patterns of the knee in gait in spastic diplegia of cerebral palsy

We studied the kinetic characteristics of the knee in patients with spastic diplegia. Twenty three children with spastic diplegia were recruited and had their 46 limbs categorised into the following four groups: jump (n=7), crouch (n=8), recurvatum (n=14) and mild (n=17). In the crouch pattern, the patients usually had a larger and longer lasting internal knee extensor moments in stance suggesting that rectus femoris had a relatively high activation. In the recurvatum pattern, the internal knee flexor moment was large and long lasting in stance. The biceps femoris showed less activity on EMG although the knee flexor moment was large and we concluded that the soft tissue behind the knee joint provided this flexor moment. In the jump knee pattern there was abnormal power generation at the knee and ankle joints in initial stance, which did not contribute to normal progression but aided upward body motion. In the mild group the kinetic data was similar to that seen in normal children. Knowledge of kinetic patterns in these patients may help in their subsequent management.