Eric Watelain

Biomechanics and physiological parameters during gait in lower-limb amputees: A systematic review

OBJECTIVE The purpose of this systematic review was to identify which biomechanical and physiological parameters are the most relevant, commonly used, able to discriminate and/or have specific clinical relevance for the gait analysis of lower-limb amputees (LLA). METHODS We performed an electronic search via the PubMed, EMBASE and ISI Web of Knowledge databases from 1979 to May 2009. Two independent reviewers assessed the title and abstract of each identified study. The quality assessment of the full text was undertaken using a 13-item checklist divided into three levels: A, B, and C. RESULTS The literature search identified 584 abstracts to be considered. After applying the inclusion criteria, we reviewed the full text of a total of 89 articles. The mean article quality was 8±2. No A-level article was found; the primary reason was a negative score in blinded outcome assessment. Sixty-six articles (74%) corresponded to a B-level, and two articles (2%) corresponded to a C-level. Twenty-one articles (24%) did not acquire enough points to be assigned to any level. In this study, we present and discuss the most commonly used and most relevant 32 parameters. Many of the parameters found were not reported in enough studies or in enough detail to allow a useful evaluation. CONCLUSION This systematic review can help researchers compare, choose and develop the most appropriate gait evaluation protocol for their field of study, based on the articles with best scores on the criteria list and the relevance of specific biomechanical and physiological parameters.

Are clinical measurements linked to the Gait Deviation Index in cerebral palsy patients

OBJECTIVE From a dataset of clinical assessments and gait analysis, this study was designed to determine which of the assessments or their combinations would most influence a low gait index (i.e., severe gait deviations) for individuals with cerebral palsy. DESIGN A retrospective search, including clinical and gait assessments, was conducted from August 2005 to September 2009. POPULATION One hundred and fifty-five individuals with a clinical diagnosis of cerebral palsy (CP) (mean age (SD): 11 (5.3) years) were selected for the study. METHOD Quinlans Interactive Dichotomizer 3 algorithm for decision-tree induction, adapted to fuzzy data coding, was employed to predict a Gait Deviation Index (GDI) from a dataset of clinical assessments (i.e., range of motion, muscle strength, and level of spasticity). RESULTS Seven rules that could explain severe gait deviation (a fuzzy GDI low class) were induced. Overall, the fuzzy decision-tree method was highly accurate and permitted us to correctly classify GDI classes 9 out of 10 times using our clinical assessments. CONCLUSION There is an important relationship between clinical parameters and gait analysis. We have identified the main clinical parameters and combinations of these parameters that lead to severe gait deviations. The strength of the hip extensor, the level of spasticity and the strength of the tibialis posterior were the most important clinical parameters for predicting a severe gait deviation.

Physical Performance Variables and Bone Mineral Density in a Group of Young Overweight and Obese Men

The aim of this study was to explore the relationships between performances obtained in different physical tests and bone parameters (bone mineral density [BMD], bone mineral content, hip geometry indices, and trabecular bone score [TBS]) in a group of young Lebanese overweight and obese adult men. Fifty-two overweight and/or obese (body mass index > 25 kg/m2) young men whose ages range from 18 to 35 yr participated in this study. Weight and height were measured, and body mass index was calculated. Body composition, BMD, cross-sectional area and section modulus (Z) of the femoral neck (FN), and TBS were measured by dual-energy X-ray absorptiometry. Maximum oxygen consumption (VO2 max, in liter per minute) was determined by direct measurement while exercising on a medical treadmill. One-repetition-maximum half-squat and maximum power (P max) of the lower limbs were measured using validated exercises. Lean mass was a positive determinant of whole-body bone mineral content (r = 0.71, p < 0.001), FN cross-sectional area (r = 0.51, p < 0.001), and FN Z (r = 0.58, p < 0.001). VO2 max (in liter per minute) was a positive determinant of whole-body BMD (r = 0.47, p < 0.001), total hip BMD (r = 0.43, p < 0.01), and FN BMD (r = 0.42, p < 0.01). VO2 max (in milliliter per minute per kilogram) was a positive determinant of TBS (r = 0.30, p < 0.05). One repetition maximum was a positive determinant of L1-L4 BMD (r = 0.33, p < 0.05). This study suggests that VO2 max (in liter per minute) is a positive determinant of BMD, and VO2 max (in milliliter per minute per kilogram) is a positive determinant of TBS in overweight and obese men.

Decreased Composite Indices of Femoral Neck Strength in Young Obese Men

The aim of the current study was to compare compression strength index (CSI), bending strength index (BSI) and impact strength index (ISI) among obese, overweight and normal-weight young women. 117 young women (20 obese, 36 overweight and 61 normal-weight) whose ages range from 18 to 35 years participated in this study. Body composition and BMD were evaluated by dual-energy X-ray absorptiometry (DXA). CSI, BSI and ISI values were significantly lower in obese and overweight women compared to normal-weight women (p < 0.001). In the whole population (n = 117), body mass index (BMI) was negatively correlated to CSI (r = −0.66; p < 0.001), BSI (r = −0.56; p < 0.001) and ISI (r = −0.54; p < 0.001). This study suggests that obesity is associated with lower CSI, BSI and ISI values in young women.

Physiological responses in handcycling. Preliminary study

INTRODUCTION In the field of sports for the disabled, this last decade has been marked by the development of handcycling. Although assessment of maximal capacity during arm exercises in cases of spinal cord injury (SCI) has been widely investigated, investigations of maximal capacity in handcyclists remain less frequent. OBJECTIVE The aim of this study was to investigate the physiological parameters of an incomplete quadriplegic athlete (cervical lesion C5-C6; ASIA-D) during an adapted incremental handcycling test and to judge the appropriateness of the test. Using such a test, it will then be possible to determine the individualized training program intensity needed to improve the athletes aerobic capacity. METHODS The athlete completed an incremental hand cycling test (i.e., an adapted Léger-Boucher test), with the handbike mounted on an ergotrainer. The athletes physiological parameters were recorded during the test, and the pedalling rate and the perceived exertion rate were estimated. Given the athletes pathology, ergonomic adaptations were necessary in order to improve comfort and propulsion quality. RESULTS The maximum values recorded (VO2peak = 1.16l/min; [La]=7.7 mmol/l; heart rate peak=133 beats/min; maximum respiratory frequency=85 cycles/min and averaged pedaling rate=95 tours/min) indicate that the incremental test, adapted for handcycling, is maximal, and consequently, it should be possible to individualize the training intensity. CONCLUSION This test is innovative and potentially applicable in a booming discipline garnering more and more interest. However, first it is necessary to extend this test to a larger population and to test the extended application in field.

Concomitant changes in clinical and posturographic data in elderly fallers during the course of an in-home anti-falling multimodal program--a preliminary investigation.

AIM OF THE STUDY The objective of this preliminary study was to evaluate the effectiveness, in terms of fall reduction, of an in-home strategy that we have developed for elderly fallers. We also aimed at finding links between the expected changes in the data obtained in static posturography and in clinical balance tests through our program. PATIENTS AND METHODS Twelve elderly patients living at home who were diagnosed as fallers (5 males and 7 females; 77.9±4.1 years) participated in the study. Our multimodal intervention lasted 6 months. Before this period, and one year later, an evaluation was conducted using cognitive (MMSE), clinical balance tests (i.e. Berg Balance Scale, Balance One leg, Timed Up and Go, and Functional Reach tests) and static posturography (where the area of body sway, velocity and medio-lateral and antero-posterior amplitudes were recorded twice, first with eyes open and then with eyes closed). RESULTS Among the 12 patients who were diagnosed as fallers, eight became non-fallers. When comparing data obtained after the intervention with those obtained beforehand, we found significant changes in all of the clinical balance tests and in the posturographic-derived variables indicating improvements in the balance control in our group of subjects. We also found significant correlations between the changes in the Berg Balance Scale scores and the changes in the area of body sway data, in antero-posterior amplitude both with eyes open and with eyes closed, and also in the medio-lateral amplitude in the eyes closed condition. CONCLUSIONS We prospectively demonstrated the relevance of our anti-falling intervention at home and of the use of posturography for clinical follow-up.

Adaptability and Prediction of Anticipatory Muscular Activity Parameters to Different Movements in the Sitting Position

Voluntary movement often causes postural perturbation that requires an anticipatory postural adjustment to minimize perturbation and increase the efficiency and coordination during execution. This systematic review focuses specifically on the relationship between the parameters of anticipatory muscular activities and movement finality in sitting position among adults, to study the adaptability and predictability of anticipatory muscular activities parameters to different movements and conditions in sitting position in adults. A systematic literature search was performed using PubMed, Science Direct, Web of Science, Springer-Link, Engineering Village, and EbscoHost. Inclusion and exclusion criteria were applied to retain the most rigorous and specific studies, yielding 76 articles, Seventeen articles were excluded at first reading, and after the application of inclusion and exclusion criteria, 23 were retained. In a sitting position, central nervous system activity precedes movement by diverse anticipatory muscular activities and shows the ability to adapt anticipatory muscular activity parameters to the movement direction, postural stability, or charge weight. In addition, these parameters could be adapted to the speed of execution, as found for the standing position. Parameters of anticipatory muscular activities (duration, order, and amplitude of muscle contractions constituting the anticipatory muscular activity) could be used as a predictive indicator of forthcoming movement. In addition, this systematic review may improve methodology in empirical studies and assistive technology for people with disabilities.

Sarcopenia and Hip Structure Analysis Variables in a Group of Lebanese Postmenopausal Women

The aim of the present study was to compare hip structural analysis variables in postmenopausal women with sarcopenia and postmenopausal women with normal skeletal muscle mass index. This study included 8 postmenopausal women (aged between 65 and 84 years) with sarcopenia and 60 age-matched controls (with normal skeletal muscle mass index (SMI)). Body composition and bone mineral density (BMD) were assessed by dual-energy X-ray absorptiometry (DXA). Weight, lean mass, Body mass index, femoral neck cross-sectional area (FN CSA), FN section modulus (Z), FN cross sectional moment of inertia (CSMI), intertrochanteric (IT) CSA, IT Z, IT CSMI, IT cortical thickness (CT), femoral shaft (FS) CSA, FS Z and FS CSMI were significantly higher (p < 0.05) in women with normal SMI compared to women with sarcopenia. In the whole population, SMI was positively correlated to IT CSA, IT Z, IT CSMI, IT CT, FS CSA, FS Z, FS CSMI, FS CT but negatively correlated to IT buckling ratio (BR) and FS BR. The present suggests that sarcopenia negatively affects hip bone strength indices in postmenopausal women.

Arm-trunk coordination in wheelchair initiation displacement: A study of anticipatory and compensatory postural adjustments during different speeds and directions of propulsion

Arm-trunk coordination during the initiation of displacement in manual wheelchair is a complex task. The objective of this work is to study the arm-trunk coordination by measuring anticipatory and compensatory postural adjustments. Nine healthy subjects participated in the study after being trained in manual wheelchair. They were asked to initiate a displacement in manual wheelchair in three directions (forward vs. left vs. right), with two speeds (spontaneous vs. maximum) and with two initial hands positions (hands on thighs vs. hands on handrails). Muscular activities in the trunk (postural component) and the arms (focal component) were recorded bilaterally. The results show two strategies for trunk control: An anticipatory adjustment strategy and a compensatory adjustment strategy with a dominance of compensation. These two strategies are influenced by the finalities of displacement in terms of speed and direction depending on the hands positions. Arm-trunk coordination is characterized by an adaptability of anticipatory and compensatory postural adjustments. The study of this type of coordination for subjects with different levels of spinal cord injury could be used to predict the forthcoming displacement and thus assist the user in a complex task.

Muscular Maximal Strength Indices and Bone Variables in a Group of Elderly Women

The aim of the present study was to explore the relations between muscular maximal strength indices and bone parameters (bone mineral density [BMD], hip geometry indices, and trabecular bone score [TBS]) in a group of elderly women. This study included 35 healthy elderly women whose ages range between 65 and 75 yr (68.1 ± 3.1 yr). BMD (in gram per square centimeter) was determined for each individual by dual-energy X-ray absorptiometry at the whole body, lumbar spine (L1-L4), total hip (TH), and femoral neck (FN). L1-L4 TBS and hip geometry indices were also evaluated by dual-energy X-ray absorptiometry. Maximal muscle strength of bench press (1-repetition maximum [RM] bench press), maximal muscle strength of leg press (1-RM leg press), and handgrip were measured using validated methods. 1-RM bench press was positively correlated to TH BMD (r = 0.40; p < 0.05), FN BMD (r = 0.41; p < 0.05), FN section modulus (r = 0.33; p < 0.05), and FN cross-sectional moment of inertia (r = 0.35; p < 0.05). 1-RM leg press was positively correlated to TH BMD (r = 0.50; p < 0.01), FN BMD (r = 0.35; p < 0.05), FN cross-sectional area (r = 0.38; p < 0.05), and TBS (r = 0.37; p < 0.05). Handgrip was correlated only to FN cross-sectional moment of inertia (r = 0.43; p < 0.01). This study suggests that 1-RM bench press and 1-RM leg press are positive determinants of BMD in elderly women.