A Compact Forearm Crutch Based on Force Sensors for Aided Gait: Reliability and Validity

Abstract

Frequently, patients who suffer injuries in some lower member require forearm crutches in order to partially unload weight-bearing. These lesions cause pain in lower limb unloading and their progression should be controlled objectively to avoid significant errors in accuracy and, consequently, complications and after effects in lesions. The design of a new and feasible tool that allows us to control and improve the accuracy of loads exerted on crutches during aided gait is necessary, so as to unburden the lower limbs. In this paper, we describe such a system based on a force sensor, which we have named the GCH System 2.0. Furthermore, we determine the validity and reliability of measurements obtained using this tool via a comparison with the validated AMTI (Advanced Mechanical Technology, Inc., Watertown, MA, USA) OR6-7-2000 Platform. An intra-class correlation coefficient demonstrated excellent agreement between the AMTI Platform and the GCH System. A regression line to determine the predictive ability of the GCH system towards the AMTI Platform was found, which obtained a precision of 99.3%. A detailed statistical analysis is presented for all the measurements and also segregated for several requested loads on the crutches (10%, 25% and 50% of body weight). Our results show that our system, designed for assessing loads exerted by patients on forearm crutches during assisted gait, provides valid and reliable measurements of loads.

Technology-Based Feedback and Its Efficacy in Improving Gait Parameters in Patients with Abnormal Gait: A Systematic Review

“…Furthermore, it is not only the system that must be individualized, but also the type of feedback used. To exemplify this trend, consider the GCH Control System [ 27 ], an instrumented forearm crutch that controls the loads exerted on the crutch when the patient has to partially discharge his/her affected limb. It includes a feedback mechanism to send information about these loads to both the physiotherapist and the patient.…”

“…Researchers need to focus on providing clinical findings [ 24 ]. Therefore, the effects of these novel devices need to be measured [ 26 , 27 ] on different study populations, considering gait parameters, therapeutic guidelines adopted, clinical results obtained, systems of assessment used, etc. Similarly, we need to analyze the efficacy of different types of extrinsic feedback, in other words, that coming from an external source [ 28 ].…”

Desarrollo de una muleta sensorizada para medir la inclinación y el peso descargado

“…Esto no sucede si se coloca un sensor en el cuerpo, porque el movimiento del cuerpo provoca aceleraciones que pueden producir un desplazamiento relativo entre el sensor y los tejidos humanos [13]. Además, en los sistemas comercializados basados en sensores vestibles atados al cuerpo, el tiempo de ajuste y puesta en marcha varía entre 5 y 10 minutos con cada usuario [14,15], mientras que, en los prototipos de muletas sensorizadas, este tiempo es de unos pocos segundos [10,21].…”

“…Por ejemplo, se puede usar para prevenir caídas y detectar determinadas situaciones durante la marcha [12]. También se han utilizado muletas sensorizadas para medir el peso descargado sobre la muleta, de forma que el paciente pueda controlar la fuerza ejercida sobre la pierna afectada [9,10,21]. En [11], se utiliza un bastón instrumentado para estimar la intención de movimiento y poder controlar un exoesqueleto.…”

“…Estos dispositivos pueden incluir sensores como acelerómetros, giróscopos, magnetómetros, barómetros, sensores de fuerza y receptores de GPS [6].Los sensores vestibles también pueden ser integrados en dispositivos de ayuda para la marcha [8]. En concreto, varios trabajos han investigado el uso de pequeños sensores integrados en una muleta, la cual es un dispositivo pasivo utilizado en la rehabilitación de la marcha [2,9,10,11,12,16,21].Actas de las XXXIX Jornadas de Automática, Badajoz, 5-7 de Septiembre de 2018 80…”