Estimation of 3D Knee Joint Angles during Cycling Using Inertial Sensors: Accuracy of a Novel Sensor-to-Segment Calibration Procedure Based on Pedaling Motion.

This paper presents a novel sensor-to-segment calibration procedure for inertial sensor-based knee joint kinematics analysis during cycling. This procedure was designed to be feasible in-field, autonomously, and without any external operator or device. It combines a static standing up posture and a pedaling task. The main goal of this study was to assess the accuracy of the new sensor-to-segment calibration method (denoted as the 'cycling' method) by calculating errors in terms of body-segment orientations and 3D knee joint angles using inertial measurement unit (IMU)-based and optoelectronic-based motion capture. To do so, 14 participants were evaluated during pedaling motion at a workload of 100 W, which enabled comparisons of the cycling method with conventional calibration methods commonly employed in gait analysis. The accuracy of the cycling method was comparable to that of other methods concerning the knee flexion/extension angle, and did not exceed 3.8°. However, the cycling method presented the smallest errors for knee internal/external rotation (6.65 ± 1.94°) and abduction/adduction (5.92 ± 2.85°). This study demonstrated that a calibration method based on the completion of a pedaling task combined with a standing posture significantly improved the accuracy of 3D knee joint angle measurement when applied to cycling analysis.

Kinematic motion abnormalities and bimanual performance in children with unilateral cerebral palsy.

AIM: To evaluate the relationship between the movement abnormalities of the impaired upper limb in children with unilateral cerebral palsy (CP) and bimanual performance. METHOD: Twenty-three children with unilateral CP (mean age 11y 10mo [SD 2y 8mo]) underwent evaluation of bimanual performance (Assisting Hand Assessment [AHA]) and a three-dimensional movement analysis to measure deviations in the movement of their affected upper limb, and compared with 23 typically developing children (TDC) (mean age 11y 11mo [SD 2y 5mo]). Kinematic indices, such as the Global Arm Profile Score (APS), which summarizes the global movement deviation of the upper limb from the norm, and the Global Arm Variable Score (AVS), which represent movement deviations for a given joint, were calculated and correlated to AHA. RESULTS: Values of kinematic indices were significantly higher in children with unilateral CP than in TDC. A strong correlation between Global-APS and AHA score (r=-0.75) was found. Other significant correlations were found with Global-AVS, especially in distal joints. INTERPRETATION: Children with unilateral CP had more movement deviations than TDC. The global movement deviation of the impaired upper limb was strongly correlated with bimanual performance. The influence of distal abnormalities confirms the importance of considering these limitations in therapeutics. WHAT THIS PAPER ADDS: Children with unilateral cerebral palsy had more movement deviations than typically developing children in unimanual tasks. A strong relationship was found between movement deviations of the impaired upper limb and bimanual performance.

Satisfaction survey toward an innovative orthosis for children with cerebral palsy with pes planovalgus.

BACKGROUND: Pes planovalgus (PPV) is common in children with cerebral palsy and can cause pain and gait alterations over time. Initial treatment of flexible PPV includes orthotics, despite a lack of consensus on the type of orthosis. We developed an innovative ankle-foot orthosis (RAFO). RAFO is a one-piece orthosis designed to correct both the valgus and the flat of the foot. Its conception situated above the malleolar enables a moderate anti equinus effect. Its precise description and fabrication's process is detailed. OBJECTIVES: We wanted to assess user's satisfaction after several months of use and looked for clinical criteria of satisfaction. STUDY DESIGN: Retrospective. METHODS: We conducted a satisfaction study through a telephonic QUEST (Quebec User Evaluation of Satisfaction with Assistive Technology) survey analysing the device and the process in children and parents. 24 parents were contacted, whose child was wearing RAFO on a daily basis for at least 4 months. 20 parents answered the questionnaire. The results were then related to clinical data to research satisfaction' criteria. RESULTS: Mean QUEST satisfaction was 4.25/5 (4.18/5 for device and 4.38/5 for process). Advantages reported concerned weight and dimensions (95%), although 20% reported the necessity to change to a shoe size above, ease of use (90%) and level of comfort (80%). Parent's satisfaction regarding perceived effectiveness was 80%. Children with equinus due to triceps surae spasticity were more susceptible to develop pain with our orthosis. CONCLUSIONS: Parents were overall very satisfied with the orthosis. Its technical characteristics allowing both to be a corrector of flat foot and valgus and at the same time to be comfortable and discreet makes it innovative. The presence of spastic equinus is a limit for its utilization.

Validity and reliability of the chronic composite XA, an upper limb motor assessment using Active Range of Motion in patients with chronic stroke.

BACKGROUND: Upper limb (UL) spastic paresis has been classically evaluated with assessments of passive movements with limited functional validity. The aim of this study was to assess whether a composite measure of active range of motion (AROM, or XA) is valid and reliable in chronic post-stroke spastic paresis. AIM: The primary objective was to investigate the validity and reliability of a composite score, comprising multiple XA measurements, to assess UL spastic paresis in patients in chronic stages post-stroke. In addition to this, an exploratory analysis was conducted to identify which muscles should be optimally included in this composite score. DESIGN: A psychometric proprieties study. SETTING: Physical and Rehabilitation Medicine Department. POPULATION: twenty-eight chronic post-stroke participants with spastic paresis. METHODS: Composite UL XA measurement in twenty-eight chronic post-stroke participants (age=59±11 years; delay post-stroke=29±37 months) with spastic paresis was repeated twice about 40 days apart in a standardized body position. Concurrent and construct validity was evaluated exploring correlation with the Fugl-Meyer Assessment Upper Extremity (FMA-UE), Action Research Arm Test (ARAT), and grip strength (JAMAR™). Reliability was assessed by calculating intraclass correlation coefficients (ICC). Regarding the exploratory analysis, a linear regression analysis was performed to examine the value of including various muscles. RESULTS: Composite XA against the resistance of elbow, wrist and finger flexors showed strong correlation with FMA-UE and ARAT (r=0.88; P<0.001 and r=0.82; P<0.001 respectively) and a weak association with grip strength (r=0.43; P=0.03). Test-retest reliability was excellent (ICC=0.92). However, the most effective regression model also included XA against the resistance of shoulder adductors as well as forearm pronator (adjusted R2=0.85; AIC=170). CONCLUSIONS: The present study provided satisfactory psychometric data for the upper limb composite active movement (CXA), derived from the Five Step Assessment. For overall measurement of UL mobility after stroke, we strongly recommend including shoulder and forearm muscles to the score. CLINICAL REHABILITATION IMPACT: Composite XA is a valid and reliable measure of upper limb motor function in chronic post-stroke patients and could be used in clinical practice and research.

Reliability and minimal detectable change of body-weight distribution and body sway between right and left brain-damaged patients at a chronic stage.

PURPOSE: To assess the reliability and minimal detectable change (MDC) of weight-bearing asymmetry (WBA) and body sway (BS) during "eyes open" (EO) and "eyes closed" (EC) conditions for those with right brain damage (RBD) and left brain damage (LBD) at a chronic stage. METHODS: Sixteen RBD and 16 LBD patients participated in two sessions within 15 days, composed of two trials of 30 s using a double force platform. Intraclass correlation coefficient (ICC2,1), the standard error of measurement (SEM), and MDC were calculated for WBA and BS (area and velocity of sway). RESULTS: Reliability of WBA was excellent (>0.75) except for EC for LBD patients (low SEM was found). The condition of EC was similar to or less reliable than that of EO. The MDC of WBA was 5.4 and 7.3% for LBD and RBD patients, respectively. Velocity of sway should be favored over the area of sway due to better reliability, with an MDC of 9 and 13 mm/s for RBD and LBD patients, respectively. CONCLUSIONS: Parameters related to WBA and BS were highly reliable, without a difference between RBD and LBD patients, but less so in the condition of EC, and could be used for clinical rehabilitation and/or research.Implications for rehabilitationWeight-bearing asymmetry (WBA) and body sway (BS) are highly reliable posturography parameters.Reliability of WBA/BS is similar among right brain damaged (RBD) and left brain damaged (LBD) patients.A change of 5-7% can be interpreted as significant for WBA for chronic stroke.The minimal detectable change in measures is slightly higher for RBD patients.

The effects of repetitive neck-muscle vibration on postural disturbances after a chronic stroke.

OBJECTIVE: We aimed to test a repeated program of vibration sessions of the neck muscles (rNMV) on postural disturbances and spatial perception in patients with right (RBD) versus left (LBD) vascular brain damage. METHODS: Thirty-two chronic stroke patients (mean age 60.9±10 yrs and mean time since stroke 4.9±4 yrs), 16 RBD and 16 LBD, underwent a program of 10 sessions of NMV over two weeks. Posturography parameters (weight-bearing asymmetry (WBA), Xm, Ym, and surface), balance rating (Berg Balance Scale (BBS), Timed Up and Go (TUG)), space representation (subjective straight ahead (SSA), longitudinal body axis (LBA), subjective visual vertical (SVV)), and post-stroke deficiencies (motricity index, sensitivity, and spasticity) were tested and the data analyzed by ANOVA or a linear rank-based model, depending on whether the data were normally distributed, with lesion side and time factor (D-15, D0, D15, D21, D45). RESULTS: The ANOVA revealed a significant interaction between lesion side and time for WBA (P<0.0001) with a significant shift towards the paretic lower limb in the RBD patients only (P=0.0001), whereas there was no effect in the LBD patients (P=0.98). Neither group showed a significant modification of spatial representation. Nonetheless, there was a significant improvement in motricity (P=0.02), TUG (P=0.0005), and BBS (P<0.0001) in both groups at the end of treatment and afterwards. CONCLUSIONS: rNMV appeared to correct WBA in RBD patients only. This suggests that rNMV could be effective in treating sustainable imbalance due to spatial cognition disorders.