Waiting time: Does it affect the physical functioning of people waiting for a total joint replacement?

This study will investigate people who are on the public waiting list for primary total hip and knee replacements. Data will include walking gait parameters, patient-reported outcome measures (questionnaires) and activity data. Data will be collected at one timepoint (pre-operative with respect to their date of referral onto the waiting list) during an appointment at the Royal Adelaide Hospital, which will take approximately 30-45 minutes. The appointment will consist of a series of questionnaires, body measurements and assessment of gait using wearable sensors and an instrumented treadmill. This study will be separated into 3 aims: 1) Test the reliability of the study methods using wearable sensors and an instrumented treadmill, 2) Test the validity of the study methods compared to the current reference standard of optical motion capture, 3) investigate whether associations exist between 1) symptom duration and 2) waiting time and walking gait. The gait capture system used at the RAH, utilises a split belt instrumented treadmill which allows individual force profiles of each leg of the participant. This allows us to determine whether the participant is favouring one limb over the other by how much force is exerted. This system also uses Inertial Measurement Units (IMUs), which have an accelerometer, magnetometer, and gyroscope. This allow the collection of gait data without the use of specialised laboratories and in settings where gait had previously not been able to be captured in, such as at home and outdoors. The key differences between Optical Motion capture (MoCap) and the proposed gait analysis methodology (IMUs and treadmill) is that less equipment is needed and the wearable sensors methodology can be used in other settings. Previous comparison studies using MoCap and IMUs have shown agreement in the gait data they collect. MoCap also requires a specialised laboratory with all the equipment set up, thus making the use of IMUs for gait analysis cheaper and less time consuming to perform. Another key difference is with the use of the treadmill, which allows the collection of multiple gait cycles of data compared to MoCap's use of force platforms.