Towards a new concept to the neurological recovery for knee stabilization after anterior cruciate ligament reconstruction based on surface electrical stimulation

Background: The knee function is critical for locomotion, providing adaptation to the terrain and power for the propulsion. This work presents the concept of the Rehabot Knee project that relies on the hypothesis that an adequate neuromuscular control is crucial for the recovery of an injured knee, with or without surgery, in order to reach the expected level of activity in a reasonable timeframe. We develop a knee brace prototype intended to provide closed-loop electrical stimulation based on the detection of instability due to lack of neuromuscular control. The objective is to analyze kinetic and kinematic variables that might relate to the unilateral knee stability. A commercial knee brace for stabilization of the knee joint after anterior cruciate ligament reconstruction has been instrumented with wearable sensors, enabling estimation of interaction forces and rotational displacements around the orthotic knee joint. We present results of preliminary trials with a healthy subject performing diverse types of loading conditions. These results indicate the feasibility of the real-time detection of the induced loading conditions that might be related to anterior-posterior tibial displacement.