Gait evaluation apparatus, gait training system, and gait evaluation method

A gait evaluation method performed by a gait training apparatus for evaluating a training gait of a paralyzed patient suffering from paralysis in an affected leg, the gait evaluation method comprising:

• providing the gait training apparatus including
• a gait assistance device configured to be attached to the affected leg, the gait assistance device including an actuator configured to control a motion of the affected leg, an upper leg frame, a lower leg frame rotatably connected to the upper leg frame, a foot frame rotatably connected to the lower leg frame, an angle sensor measuring an angle formed by the upper leg frame and the lower leg frame around a hinge axis, and a load sensor being disposed in the foot frame and measuring a vertical load applied to a sole of the patient;
• a treadmill that serves as a gait surface on which the patient walks;
• a frame, a top of the frame supporting a front side pulling unit, a rear side pulling device, and a harness pulling unit, the front side pulling unit including a front side wire connected to a front side of the gait assistance device, the rear side pulling device including a rear side wire connected to a rear side of the gait assistance device, and the harness pulling unit including a harness wire connected to a harness attached to the patient to prevent the patient from falling on the treadmill;
• and
• a display device mounted on the frame
• acquiring, according to a gait motion, a plurality of motion amounts of a paralyzed body portion, which includes the affected leg, the plurality of motion amounts obtained from image data received from a camera, a posture sensor provided on the patient, and the load sensor and the angle sensor provided on the gait assistance device,
• evaluating that the gait motion is an abnormal gait in a case where at least one of the motion amounts from the plurality of motion amounts meets any one of a plurality of abnormal gait criteria set in advance for a trial in which the patent continuously walks on the treadmill,
• transmitting, to the display device, a display signal that causes the display device to display a determination result indicating whether the gait motion is the abnormal gait, and
• operating the front side pulling unit and the rear side pulling unit according to movement of the affected leg, and operating the harness pulling unit based on movement of the patient
• wherein the abnormal gait criteria are set to different criteria in a swing phase and a stance phase of the affected leg, and
• wherein the abnormal gait criteria include at least two or more first criteria, which are criteria relevant to motion amounts of different parts of the paralyzed body portion, the first criteria being selected from a criterion relevant to a motion amount of a trunk, a criterion relevant to a motion amount of a knee joint, and a criterion relevant to a motion amount of a foot portion from an ankle, or at least two second criteria, which are criteria relevant to motion amounts of the same part of the paralyzed body portion in different directions, the second criteria including a criterion relevant to a motion amount of a trunk in a gait direction and a criterion relevant to a motion amount of the trunk in an orthogonal direction perpendicular to the gait direction,
• wherein the criterion relevant to the motion amount of the trunk, the criterion relevant to the motion amount of the trunk in the gait direction, and the criterion relevant to the motion amount of the trunk in the orthogonal direction perpendicular to the gait direction are each based on at least one of an inclination angle of the trunk of a forward direction during a stance of the affected leg being equal to or greater than a first predetermined reference angle, an inclination angle of the trunk toward a side of the affected leg during the stance of the affected leg being equal to or greater than a second predetermined reference angle, and an inclination angle of the trunk in the forward direction during a swing of the affected leg being equal to or greater than a third predetermined reference angle,
• wherein the criterion relevant to the motion amount of the knee joint is based on a bending angle of the knee joint during the stance of the affected leg being less than a fourth predetermined reference angle, and
• wherein the criterion relevant to the motion amount of the foot portion from the ankle is based on at least one of a distance along the gait direction from a hip joint to a foot joint when the affected leg has finished the swing phase and landed is less than a first predetermined reference distance, the vertical load applied to the sole of the patient is larger than a predetermined reference load, and a distance along the gait direction from the hip joint to the foot joint at a time of swinging at which the affected leg switches from the stance phase to the swing phase is equal to or greater than a second predetermined reference distance.

A gait training apparatus for training a gait of a paralyzed patient suffering from paralysis in an affected leg, the gait training apparatus comprising:

• a gait assistance device configured to be attached to the affected leg, the gait assistance device including an actuator configured to control a motion of the affected leg, an upper leg frame, a lower leg frame rotatably connected to the upper leg frame, a foot frame rotatably connected to the lower leg frame, an angle sensor measuring an angle formed by the upper leg frame and the lower leg frame around a hinge axis, and a load sensor being disposed in the foot frame and measuring a vertical load applied to a sole of the patient;
• a frame surrounding a gait surface on which the patient walks, a top of the frame supporting a front side pulling unit, a rear side pulling device, and a harness pulling unit, the front side pulling unit including a front side wire connected to a front side of the gait assistance device, the rear side pulling device including a rear side wire connected to a rear side of the gait assistance device, and the harness pulling unit including a harness wire connected to a harness attached to the patient to prevent the patient from falling;
• a display device mounted on the frame;
• and
• a controller including processing circuitry configured to:
• acquire, according to a gait motion, a plurality of motion amounts of a paralyzed body portion, which includes the affected leg, the plurality of motion amounts obtained from image data received from a camera, a posture sensor provided on the patient, and the load sensor and the angle sensor provided on a gait assistance device,
• evaluate that the gait motion is an abnormal gait in a case where at least one of the motion amounts from the plurality of motion amounts meets any one of a plurality of abnormal gait criteria set in advance for a trial in which the patient continuously walks on the gait surface,
• transmit, to the display device, a display signal that causes the display device to display a determination result indicating whether the gait motion is the abnormal gait,
• wherein the processing circuitry of the controller is further configured to operate the front side pulling unit and the rear side pulling unit according to movement of the affected leg, and operate the harness pulling unit based on movement of the patient,
• wherein the abnormal gait criteria are set to different criteria in a swing phase and a stance phase of the affected leg, and
• wherein the abnormal gait criteria include at least two first criteria, which are criteria relevant to motion amounts of different parts of the paralyzed body portion, the first criteria being selected from a criterion relevant to a motion amount of a trunk, a criterion relevant to a motion amount of a knee joint, and a criterion relevant to a motion amount of a foot portion from an ankle, or at least two second criteria, which are criteria relevant to motion amounts of the same part of the paralyzed body portion in different directions, the second criteria including a criterion relevant to a motion amount of a trunk in a gait direction and a criterion relevant to a motion amount of the trunk in an orthogonal direction perpendicular to the gait direction,
• wherein the criterion relevant to the motion amount of the trunk, the criterion relevant to the motion amount of the trunk in the gait direction, and the criterion relevant to the motion amount of the trunk in the orthogonal direction perpendicular to the gait direction are each based on at least one of an inclination angle of the trunk of a forward direction during a stance of the affected leg being equal to or greater than a first predetermined reference angle, an inclination angle of the trunk toward a side of the affected leg during the stance of the affected leg being equal to or greater than a second predetermined reference angle, and an inclination angle of the trunk in the forward direction during a swing of the affected leg being equal to or greater than a third predetermined reference angle,
• wherein the criterion relevant to the motion amount of the knee joint is based on a bending angle of the knee joint during the stance of the affected leg being less than a fourth predetermined reference angle, and
• wherein the criterion relevant to the motion amount of the foot portion from the ankle is based on at least one of a distance along the gait direction from a hip joint to a foot joint when the affected leg has finished the swing phase and landed is less than a first predetermined reference distance, the vertical load applied to the sole of the patient is larger than a predetermined reference load, and a distance along the gait direction from the hip joint to the foot joint at a time of swinging at which the affected leg switches from the stance phase to the swing phase is equal to or greater than a second predetermined reference distance.