Alice Bonnefoy-Mazure

Trunk movements during gait in cerebral palsy

BACKGROUND Lower limb deficits have been widely studied during gait in cerebral palsy, deficits in upper body have received little attention. The purpose of this research was to describe the characteristics of trunk movement of cerebral palsy children in terms of type of deficits (diplegia/hemiplegia) and gross motor function classification system (1, 2 or 3). METHODS Data from 92 cerebral palsy children, which corresponds to 141 clinical gait analysis, were retrospectively selected. Kinematic parameters of trunk were extracted from thorax and spine angles in the sagittal, transverse and coronal planes. The range of motion and the mean positions over the gait cycle were analysed. Intra-group differences between the children with diplegia or hemiplegia, gross motor function classification systems 1 to 3 and typically developing participants were analysed with Kruskal-Wallis tests and post hoc tests. Pearson correlation coefficients between the gait profile score normalised walking speed and kinematic parameters of the thorax were assessed. FINDINGS The results revealed: 1) the range of motion of the thorax and spine exhibited more significant differences between groups than the mean positions; 2) greater levels of impairment were associated with higher thorax range of motion, and 3) the children with diplegia and gross motor function classification system 3 exhibited a greater range of motion for all planes with the exception of spine rotation. INTERPRETATION This study confirmed that greater levels of impairment in cerebral palsy are associated with greater thorax range of motion during gait. The thorax plays an important role during gait in cerebral palsy.

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.

Full body gait analysis may improve diagnostic discrimination between hereditary spastic paraplegia and spastic diplegia: a preliminary study.

Hereditary spastic paraplegia (HSP) and spastic diplegia (SD) patients share a strong clinical resemblance. Thus, HSP patients are frequently misdiagnosed with a mild form of SD. Clinical gait analysis (CGA) has been highlighted as a possible tool to support the differential diagnosis of HSP and SD. Previous analysis has focused on the lower-body but not the upper-body, where numerous compensations during walking occur. The aim of this study was to compare the full-body movements of HSP and SD groups and, in particular, the movement of the upper limbs. Ten HSP and 12 SD patients were evaluated through a CGA (VICON 460 and Mx3+; ViconPeak(®), Oxford, UK) between 2008 and 2012. The kinematic parameters were computed using the ViconPeak(®) software (Plug-In-Gait). In addition, the mean amplitude of normalised (by the patients height) arm swing was calculated. All patients were asked to walk at a self-selected speed along a 10-m walkway. The mean kinematic parameters for the two populations were analysed with Mann-Whitney comparison tests, with a significant P-value set at 0.05. The results demonstrated that HSP patients used more spine movement to compensate for lower limb movement alterations, whereas SD patients used their arms for compensation. SD patients had increased shoulder movements in the sagittal plane (Flexion/extension angle) and frontal plane (elevation angle) compared to HSP patients. These arm postures are similar to the description of the guard position that toddlers exhibit during the first weeks of walking. To increase speed, SD patients have larger arm swings in the sagittal, frontal and transversal planes. Upper-body kinematics, and more specifically arm movements and spine movements, may support the differential diagnosis of HSP and SD.

Effects of contracture on gait kinematics: A systematic review.

BACKGROUND Contractures of a major joint in the lower limbs may impair human walking in addition to other daily living activities. A contracture is defined as the inability of a joint to perform the full range of motion and excessive resistance during passive mobilization of the joint. Few studies have reported methods describing how to evaluate contractures. Understanding the association among all of these studies seems essential to improve patient management. Therefore, we conducted a systematic review on this topic to elucidate the influence of contractures on gait kinematics. METHODS An electronic search in the literature will be conducted. Studies were screened by title and abstract and full texts were evaluated secondarily for definitive inclusion. The quality of the included studies was assessed independently by the two review authors with the Modified Quality Assessment Checklist. The included studies were separated into three categories: pathological contracture versus healthy controls (descriptive), simulated contracture versus healthy controls (experimental), and pre- and post-kinematics after surgical muscle lengthening (surgery). FINDINGS From a total of 4402 references, 112 original articles were selected, and 28 studies were identified in this systematic review. No significant difference between raters was observed on the total score of the Modified Quality Assessment Checklist. INTERPRETATION Contractures influence walking depending on the location (muscle) and the contracture level (muscle-tendon length). After giving a definition of contracture, this review identified some contracture alterations, such as plantarflexion, knee flexion and hip flexion contractures, with a kinematic description and presented possible different compensations.

A descriptive analysis of the upper limb patterns during gait in individuals with cerebral palsy

Patients with cerebral palsy (CP) are characterized by a large diversity of gait deviations; thus, lower limb movements during gait have been well-analyzed in the literature. However, the question of upper limb movements and, more particularly, arm movements during gait has received less attention for CP patients as a function of the disease type (Hemiplegic, HE or Diplegic, DI). Thus, the aim of this study was to investigate upper limb movements for a large group of CP patients; we used a retrospective search, including upper limb kinematic parameters and 92 CP patients (42 females and 50 males, mean±standard deviation (SD); age: 15.2±6.7 years). The diagnoses consisted of 48 HE and 44 DI. A control group of 15 subjects (7 females and 8 males, age: 18.4±8.4 years) was included in the study to provide normal gait data. For the DI patients and CG, 88 arms and 30 arms were analyzed, respectively. For the HE patients, 48 affected arms and 48 non-affected arms were analyzed. The kinematic parameters selected and analyzed were shoulder elevation angles; elbow flexion angles; thorax tilt and obliquity angles; hand vertical and anterior-posterior movements; and arm angles. Several gait parameters were also analyzed, such as the gait profile score (GPS) and normalized speed. Statistical analyses were performed to compare CG with the affected and non-affected upper limbs of HE patients and with the two upper limbs of DI patients. The results show that HE and DI patients adopt abnormal upper limb movements. However, DI patients have greater shoulder, elbow, thorax and arm angle movements compared with HE patients. However, HE patients adopt different movements between their affected and non-affected arms. Thus, the patients used their upper limbs to optimize their gait more where gait deviations were more important. These observations confirm that the upper limbs must be integrated into rehabilitation programs to improve inter-limb coordination.

Validity and Reliability of Spine Rasterstereography in Patients With Adolescent Idiopathic Scoliosis.

Study Design. Test–retest study. Objective. This study aimed to evaluate the validity and reliability of rasterstereography in patients with adolescent idiopathic scoliosis (AIS) with a major curve Cobb angle (CA) between 10° and 40° for frontal, sagittal, and transverse parameters. Summary of Background Data. Previous studies evaluating the validity and reliability of rasterstereography concluded that this technique had good accuracy compared with radiographs and a high intra- and interday reliability in healthy volunteers. To the best of our knowledge, the validity and reliability have not been assessed in AIS patients. Materials. Thirty-five adolescents with AIS (male = 13) aged 13.1 ± 2.0 years were included. To evaluate the validity of the scoliosis angle (SA) provided by rasterstereography, a comparison (t test, Pearson correlation) was performed with the CA obtained using 2D EOS® radiography (XR). Three rasterstereographic repeated measurements were independently performed by two operators on the same day (interrater reliability) and again by the first operator 1 week later (intrarater reliability). The variables of interest were the SA, lumbar lordosis, and thoracic kyphosis angle, trunk length, pelvic obliquity, and maximum, root mean square and amplitude of vertebral rotations. The data analyses used intraclass correlation coefficients (ICCs). Results. The CA and SA were strongly correlated (R = 0.70) and were nonsignificantly different (P = 0.60). The intrarater reliability (same day: ICC [1, 1], n = 35; 1 week later: ICC [1, 3], n = 28) and interrater reliability (ICC [3, 3], n = 16) were globally excellent (ICC > 0.75) except for the assessment of pelvic obliquity. Conclusion. This study showed that the rasterstereographic system allows for the evaluation of AIS patients with a good validity compared with XR with an overall excellent intra- and interrater reliability. Based on these results, this automatic, fast, and noninvasive system can be used for monitoring the evolution of AIS in growing patients instead of repetitive radiographs, thereby reducing radiation exposure and decreasing costs. Level of Evidence: 4

Are clinical parameters sufficient to model gait patterns in patients with cerebral palsy using a multilinear approach

The aim of this study was to evaluate whether clinical parameters are sufficient using, a multilinear regression model, to reproduce the sagittal plane joint angles (hip, knee, and ankle) in cerebral palsy gait. A total of 154 patients were included. The two legs were considered (308 observations). Thirty-six clinical parameters were used as regressors (range of motion, muscle strength, and spasticity of the lower). From the clinical gait analysis, the joint angles of the sagittal plane were selected. Results showed that clinical parameter does not provide sufficient information to recover joint angles and/or that the multilinear regression model is not an appropriate solution.

Feasibility and reliability of using an exoskeleton to emulate muscle contractures during walking

Contracture is a permanent shortening of the muscle-tendon-ligament complex that limits joint mobility. Contracture is involved in many diseases (cerebral palsy, stroke, etc.) and can impair walking and other activities of daily living. The purpose of this study was to quantify the reliability of an exoskeleton designed to emulate lower limb muscle contractures unilaterally and bilaterally during walking. An exoskeleton was built according to the following design criteria: adjustable to different morphologies; respect of the principal lines of muscular actions; placement of reflective markers on anatomical landmarks; and the ability to replicate the contractures of eight muscles of the lower limb unilaterally and bilaterally (psoas, rectus femoris, hamstring, hip adductors, gastrocnemius, soleus, tibialis posterior, and peroneus). Sixteen combinations of contractures were emulated on the unilateral and bilateral muscles of nine healthy participants. Two sessions of gait analysis were performed at weekly intervals to assess the reliability of the emulated contractures. Discrete variables were extracted from the kinematics to analyse the reliability. The exoskeleton did not affect normal walking when contractures were not emulated. Kinematic reliability varied from poor to excellent depending on the targeted muscle. Reliability was good for the bilateral and unilateral gastrocnemius, soleus, and tibialis posterior as well as the bilateral hamstring and unilateral hip adductors. The exoskeleton can be used to replicate contracture on healthy participants. The exoskeleton will allow us to differentiate primary and compensatory effects of muscle contractures on gait kinematics.

Mechanics of standing and crouching sprint starts

ABSTRACT The aim of this study was to compare the kinetic and kinematic parameters of standing and crouch sprint starts. Parallel starts (PS), false starts (FS), jump starts (JS) and crouch starts (3PS) were compared. Eighteen participants performed each start on a force plate and six infrared cameras captured the three-dimensional coordinates of 36 retro-reflective markers. Performance during a five-metre sprint (T5m) was analysed. Duration of the start phase (Tstart), mean values of horizontal and total ground reaction forces (GRFs) (Fx_mean and Ftot_mean), ratio of force (RF), maximal power (Pmax) and kinetic energy (KE) of each limb were calculated. Significant differences were found for T5m, Tstart, KE, Pmax, Fx_mean, Ftot_mean and RF for the crouch start compared to the other starts (P ≤ 0.05). Significant correlations were found between T5m and Tstart (r = 0.59; P ≤ 0.001), and T5m and Pmax, Fx_mean and RF (−0.73 ≤ r ≤ −0.61; P ≤ 0.001). To conclude, the crouch start resulted in the best performance because Tstart was shorter, producing greater Pmax, Fx_mean with a more forward orientation of the resultant force. Greater KE of the trunk in each start condition demonstrated the role of the trunk in generating forward translation of the centre of mass (CM).

Gait evolution in a family with hereditary spastic paraplegia

BACKGROUND The degree of disability in patients with hereditary spastic paraplegia has been reported variable even in members of the same family (same gene mutation). Moreover, it has been established that patients with hereditary spastic paraplegia should be treated differently from cerebral palsy patients due to the progressive nature of this disease. However, the gait evolution of hereditary spastic paraplegia showing onset symptoms at an early age has been described as stable. Therefore, this study aims to evaluate the walking ability and the influence of treatments on gait evolution in a family with hereditary spastic paraplegia. METHODS Clinical gait analyses were performed in six hereditary spastic paraplegia patients from the same family with a follow-up of 4-15 years. RESULTS Based on the gait deviation index, results showed a large variation of walking ability in these patients and no statistical difference between the first and last examination. In fact, three patients have improved their gait (from childhood to adolescence) whereas three patients worsened their gait. CONCLUSIONS Gait alterations in a family with hereditary spastic paraplegia are heterogeneous. Gait evolution in hereditary spastic paraplegia with early symptoms had a tendency to improve gait until adolescence with adapted treatments and to decline in the adulthood.