Perioperative Case Series: Qualitative Evaluation of Gait Cycle and Ground in Knee Arthroplasty Patients

Gait analysis is a quick and powerful tool with a wide range of clinical applications in various fields. However, due to the expensive and highly specialized equipment required, gait studies are mostly limited to academic research centers and small sample sizes and no large-scale, randomized controlled trials have been performed. Several authors have proposed inexpensive accelerometer-based systems to remedy this situation. Through mathematic transformation they adequately measure step time and length. With these systems however only temporal spatial gait parameters can be recorded; kinetic gait parameters, such as ground reaction force, cannot be measured. As these kinetic parameters are important for clinical studies, especially in fracture and rehabilitation research different methods are needed. Its availability is mainly limited to research centers, conventional gait analysis is further hindered by its stationarity and that it only allows momentary views of the patient's gait in a confined research environment. Even smaller, wearable systems have to be attached to an external apparatus, or are limited by their battery capacity, data storage and other device specific factors. Furthermore, the use of these systems is at an early clinical stage and their full potential not yet developed. As most disease processes are continuous, tools with long-term, continuous measuring capabilities are needed. For this reason a new pressure-measuring insole with built in battery and data storage was developed in cooperation with the AO Foundation(AO Foundation, Davos, Switzerland). The system offers complete independence from any external measures for up to 4 weeks and monitors a patient step during this time. The purpose of this pilot study is to investigate which how TKA arthroplasty may impact gait during early and medium term rehabilitation phase. This will be done through the use of the OpenGo Sensor Insole (Moticon GmbH).