Aim: Low-cost active video games (AVG) are of growing interest for use in home-based physical therapy regimes. This study investigates typical upper-limb movement patterns and variations during AVG play in children with cerebral palsy.

Methods: Sixteen children (9.5 ± 1.6 years ) with hemiplegic or diplegic cerebral palsy (GMFCS Level I) participated in the study. A 7-camera Vicon MX 3D Optical Capture System was used to measure and record their upper limb movements as they played three different AVGs on the Nintendo Wii system.

Results: Play style during Wii sports games tended to be either realistic or non-realistic. All players used realistic movements when playing Wii Bowling, while 69% (n=11) and 63% (n=10) played realistically during Wii Tennis and Wii Boxing, respectively. Realistic movements tended to elicit greater use of: (a) the more proximal joints, and (b) the non-dominant/hemiplegic limb (in bilateral games). Play style may be influenced by personal or predisposing factors (e.g. MACS level, gender, experience with AVGs).

Conclusion: Movement patterns and styles vary widely between children during AVG play with the Nintendo Wii. The design of AVG-based therapies should consider these variations and their implications in order to maximize therapeutic benefit. Future studies should focus on measuring the efficacy of AVG-based therapies for home use.

A simple and cost effective technique of video gait analysis applicable within rehabilitation clinics and clinical gait laboratories has been developed. The purpose of this study was to determine intra- and inter- rater reliability of kinematic and temporo-spatial gait parameters measured using the commercially available ProTrainer system (Sports Motion Inc®, Cardiff, CA) software, a printed vinyl walk mat and a video camera. Twelve healthy adults, four stroke patients and three raters participated in the study. The experimental setup comprised the walk mat, paper ‘bulls-eye’ markers, four photoswitches mounted on tripods, a light indicator, video camera, and a computer with the software. Participants performed three gait trials each up and down the walk mat. Three raters evaluated the results using the ProTrainer system (Sports Motion Inc®, Cardiff, CA) software. Values were extracted for kinematic and temporo- spatial gait measurements. Data were analysed using Intraclass Correlation Coefficient (ICC) for intra-rater reliability to calculate ICC values with 95% Confidence Intervals. Cronbach’s coefficient alpha was used to quantify the intra-rater reliability. The ICC values for both intra and inter-rater reliability ranged between 0.731 and 1.000. The results suggest this gait measurement technique is simple, reliable, effective and easy to implement as a gait outcome measuring system.

Background Clinical assessment and conventional imaging, which are currently used to monitor fracture healing, do not provide information on the mechanical properties of the healing construct. This limits their use in patient management decisions. Differentially loaded radiostereometric analysis (DLRSA) is a technique developed to assess the mechanical properties of healing fractures in vivo. DLRSA measures the relative micromotion of tantalum beads inserted into bone fracture fragments in response to load across the fracture site. To date, these loads have been applied axially, although in fractures fixed with devices which are highly resistant to axial loads, such as locked intramedullary nails, torsional testing may be more sensitive to healing. The aim of this study was to establish a method to investigate DLRSA using torsional loading for clinical application.

Methods A device was designed and built to apply torsional loads to the tibia. The test case was an oblique plain corrective osteotomy of a tibial diaphysis stabilized with an intramedullary nail and with tantalum beads inserted into the two adjacent bone segments. Post surgical examinations were made at 2 weeks, 2, 4, and 6 months as well as 1 and 2 years. Healing was monitored with the use of plain film radiographs, computed tomography (CT) and DLRSA. Axial loads of 30kg and an external torsion of 5Nm were applied during DLRSA examinations and the resultant displacement and stiffness were calculated.

Results Torsional DLRSA demonstrated progressive changes in angular displacements and torsional stiffness consistent with the fracture healing observed by CT. By contrast, axial DLRSA was not informative and was more reflective of the stability of the fixation than healing bone.

Conclusion The addition of torsional assessments to DLRSA provides an important investigative option in assessing the biomechanical properties of bone healing in vivo .

Objective: Evaluate predictions of stance time symmetry and stance force symmetry from wireless bilateral instrumented shoe insoles designed for rehabilitation using smartphone applications to provide real-time feedback.

Design: Cross-sectional study.

Subjects: Five subjects with no known gait abnormalities.

Methods: Subjects performed ten trials of three conditions: walking without a limp, limping on the right foot, and limping on the left foot, with data captured simultaneously with two force plates and the instrumented shoe insoles. Linear regression analyses were used to develop prediction equations and significance.

Results: The regression between the instrumented shoe insole and the force plate resulted in R-squared values ranging from 0.952 to 0.998 for stance time symmetry using symmetry ratio, and from 0.936 to 0.994 for stance force symmetry using a cumulative loading measure for force. With peak and average loading measures, R-squared values were lower and more variable.

Conclusion: Symmetry based on stance times or stance forces was highly predicted using the instrumented shoe insoles. Instrumented shoe insoles and real-time feedback on a smartphone could be used in the future for improving patient compliance with weight-bearing regimens or other time or force based symmetry analyses outside of the gait laboratory setting.

Inexpensive, unobtrusive 3D motion tracking of human gait is of increasing interest for the medical and entertainment industries. Of particular interest are rehabilitative applications. For instance, being able to measure foot travel, e.g. stride length or foot clearance, would be very useful. Approaches using low-cost MEMS inertial measurement units have often been limited by requiring expensive calibration procedures and by the sensor’s inherent noise and bias drift. The authors apply two techniques to improve IMU based gait tracking: a novel calibration routine and a zero-velocity bias update algorithm. The application of these aids reduces error by an average of 99.55% over six trails. Results show a 5.96% tracking accuracy in the progressive direction, which corresponds to errors on the centimeter scale.