The overall goal of this procedure is to collect, analyze, and display relevant human movement data in the shortest time possible. This is accomplished by first conducting a baseline movement analysis session to determine normal movement characteristics. The second step is to determine which movement characteristic will be modified based on the analysis of normal characteristics.
Next movement modification trials are conducted, which involves displaying real-time movement data in conjunction with a target depicting the amount of change to be achieved. The final step is to determine the effectiveness of the modified movement based on predetermined outcomes and plan for subsequent sessions of appropriate. Ultimately, real-time movement modification is used to provide a quick and accurate method of changing movement parameters.
The main advantage of this technique over standard motion analysis is that there's no delay between the collection and analysis of data. This method can help answer key questions in the movement disorders field, such as which movement modification techniques are most feasible and which ones are most effective for restoring function. Demonstrating the procedure will be Jud, a graduate student from the laboratory To begin system preparation for this protocol, first, clear the capture volume of any reflective material that may be observed by the cameras.
This decreases the chances of actual skin based markers being confused with stationary background markers during testing, and improves the overall accuracy of the session. Next, calibrate the cameras by aiming all cameras on stationary markers at fixed positions within the laboratory. Then extend the static calibration to dynamic movements using moving markers placed at known distances.
Be sure to cover as much of the capture volume as possible to optimize the calibration. Now, organize all materials, including reflective markers and measurement devices to be used for patient preparation. This improves efficiency during testing and reduces patient burden To begin patient preparation First, expose as much skin as possible over the joints and body segments intended to be measured.
Minimize the amount of loose fitting clothing and use tape or clips to constrain any pieces of clothing that may interfere with the ability of the cameras to visualize the reflective markers. Next, for maximum adherence between the marker and the skin, wipe the area clear. Using rubbing alcohol.
Now palpate for key anatomical landmarks based on the marker set to be used. Marking the skin at the actual landmark will improve accuracy for marker placement and provide information necessary in case markers fall off. During assessment, affix the reflective markers over the anatomical landmarks according to the specifications of the marker set.
Most marker sets will include a minimum of 12 to 15 markers placed bilaterally over the lower limbs and various anatomical landmarks of the upper body. It is important to note that the ability to recreate actual skeletal movement will depend on the positioning of skin based markers. As such, careful consideration must be made when determining the biomechanical model to be used.
Take measurements for important anthropometric data if required. Depending on the biomechanical model, these data may be needed to calculate segment lengths, positions of joint centers of rotation, and overall inertial properties of the moving segments and limbs during offline processing of biomechanics data. To begin motion analysis and delivery of real-time feedback, first, have the subject stand in the middle of the capture volume for an initial static trial lasting approximately three seconds.
This trial is necessary to ensure that all relevant markers are visible and to calculate segment orientations. Now using the data collection software label all markers as appropriate and create a template specific to the anthropometric characteristics of the individual. Matching marker.
Placement to the individual body size will improve the real-time tracking and analysis of data. It is especially important to create a model of movement that can incorporate redundancies of marker positioning. Next, perform a few initial motion analysis trials.
This is required to obtain baseline data and can also be used as the first mechanism of providing feedback of results to the patient. Have the therapist explain the purpose of the intended movement modification. This should include both biomechanical and clinical rationales for the modification and how it is unique to the given pathology.
Demonstration of the movement modification by the therapist will enhance motor learning by the patient. The movement modification will typically be determined based on the biomechanical and clinical presentation of the patient during treatment or the research question to be examined. If solely for research purposes.
Now begin the movement retraining session. If using a treadmill match the speed as closely as possible to the patient's self-selected walking speed on level ground, and provide a couple of minutes to reach a steady state walking. This also allows the patient to become familiar and comfortable with the equipment experimental setup and protocol.
Provide feedback to the patient during performance of the movement. Start with less technical methods, such as verbal feedback, then progress to realtime biofeedback. Real-time biofeedback should include clear display of a maximum of one movement variable at a time.
A combination of these approaches is beneficial during early training. Provide sufficient time for the patient to practice the new movement. Effective motor learning is not achieved instantaneously.
Instead, constant practice of the new movement characteristics will assist in ensuring reformulation of the motor program responsible for that movement. A typical retraining intervention may require eight to 10 focus training sessions each lasting between 30 and 60 minutes. Finally, perform a few follow-up motion analysis trials off the treadmill.
This is an important step to determine what immediate retention effects occurred as a result of the training. These data can also be used for more in-depth analysis of movement characteristics offline. Following the session.
During the debriefing, discuss the important findings and outcomes of the session with the patient. Important factors to focus on should include variability and performance adherence to the prescribed movement modification and further description of the rationale and importance of the modification. Also, obtain input regarding the session from the patient.
Given that each patient's preferences will likely differ, it may be necessary to modify the delivery of the intervention for a given individual. These preferences should be identified early to optimize effectiveness. Finally, determine the plan for subsequent training sessions if necessary, if a multi-session intervention is chosen.
Subsequent training sessions should use a faded feedback approach to enhance motor learning, provide less overall feedback and alternate between time blocks of feedback and no feedback in future sessions. Here we see sample lateral trunk lean angle during a normal walking trial and a trial where the patient was instructed to obtain a maximum amount of lateral trunk lean of approximately six degrees. Data depicted are from a single gait cycle where 0%is initial contact of one limb and 100%is toe off of the same limb.
Resultant effects on knee joint loading can be seen here. The general pattern of the knee joint movement and subsequent loading within the joint did not differ appreciably between the normal and modified trials. Instead, the magnitude was reduced throughout.
After watching this video, you should have a good understanding of how to perform a standard motion analysis session and supplement it with the ability to provide real-time performance information back to the patient.
