Indego is a lightweight, modular exoskeleton helping people with little or no movement in the legs to stand and walk. Indego provides Users with trunk support and powered assistance at the hips and knees. The User’s ankle joints are supported by a flexible, height-adjustable carbon fiber ankle foot orthosis (AFO). While this AFO does not provide any powered assist, its flexibility can allow Users to transition over thresholds, ramps, grass, sidewalks and other uneven terrain.
Why all the excitement surrounding Indego Exoskeleton?
Physicians, physical therapists (PT), exercise specialists (ES), and persons with Spinal Cord Injury and other neurological conditions are excited about Indego for a number of reasons, including:
- Indego’s weight, size and modularity
- Indego offers two Software Suite Options, depending on the User’s abilities
- Indego can be used with a variety of stability aids depending on the User’s abilities or preferences
Weight, size and modularity
At only 26 pounds (13 kg), Indego is the lightest bilateral lower extremity exoskeleton on the market that provides as much or as little powered assist as the User requires. Indego is also modular, meaning it has five pieces (1 hip, 2 upper legs, 2 lower legs) that connect to form the device. Indego’s modularity allows the User to put it on, take it off, wear it in his or her own personal wheelchair, and/or easily transport Indego in a 22” (56 cm) duffle bag. The size, weight and modular design is also beneficial for rehabilitation professionals to work with patients over inside or outside surfaces for additional challenges.
Two software suite options: Motion+ and Therapy+
Motion+ and Therapy+ Software Suites are two available operational choices for use within the same Indego hardware. Both Suites offer Certified Indego Specialists (PT or ES) and Users with a variety of unique functions for exercise, gait training, or alternative mobility from a wheelchair. Some Indego Specialists see either Motion+ or Therapy+ as an obvious choice based on the patient’s clinical presentation. Others see the two software suites not as a choice, but as part of a progression (i.e. beginning with one software suite and progressing to the other).
The diagram below is a simplified representation of Motion+ and Therapy+.
Motion+ was originally designed for persons with significant paralysis in their trunk and legs, such as those with motor complete SCI or very weak AIS C individuals. Within Motion+, Indego operates like a “legged Segway”. To walk forward, the User must lean forward at the hips to change the thigh angle. To stop walking, the User must simply maintain upright after the lead foot is on the ground (stop leaning forward). This simple approach to walking is intuitive and easy for both the Indego Specialists and Users to learn. Since Motion+ walking is posture based, the User is in control of when they do or do not want to stand up, walk, stop or sit down. Motion+ mode could be used either in a rehabilitation center or at a person’s home.
Additional key features of Motion+ include:
- Stepping under Motion+ is “trajectory based,” meaning the steps are designed to follow a certain path for safety and predictability for the User.
- Within this “trajectory based” step, Users still have the “freedom” to incorporate their own muscles when able. This “freedom” can be accomplished by decreasing the amount of powered assist from left to right and for the hips or knees using the Variable Assist function. The amount of powered assist can be decreased in 10% increments at the left and right hip and knee joints from 100% to 0 % based on the User’s muscle performance.
- Adjustable levels of Indego Vibration provide the signal for motion, alerting the Indego Specialist and User that if they feel vibration, they are in a position to move. If they are not ready to move, they simply back out of the posture.
- Pre-Gait Training, which allows Users to perform a variety of Indego pre-gait activities, such as standing exercises, balance work and strengthening.
How fast can a person walk using Motion+? The average Indego walking speed in multiple clinical trials is approximately 0.5 m/s. This speed is largely dictated by the User’s lean, not just the iPod settings. This average speed in clinical trials may not be representative of the true maximal speed achievable within Indego. Additionally, a new option within the Motion+ Suite called Advanced Gait is currently being developed which, if deemed safe by the Indego Specialist, could allow Users to walk much faster than 0.5 m/s.
Therapy+, on the other hand, was designed specifically for rehabilitation use for persons with lower extremity weakness that are strong enough to at least initiate stepping, such as those with stroke or SCI with significant muscle preservation on one or both legs (i.e. a person with strong AIS C SCI). To walk forward, the User simply initiates the step, and Indego will assist as much or as little as is necessary. To stop walking, the User stops initiating the steps. This initiation based walking requires the User to be actively engaged and participating for the duration of the rehabilitation session. Indego Specialists can employ a number of different creative approaches using Therapy+ depending on the specific goals of the session (i.e. gait training, gait kinematics, strengthening, neuromuscular reeducation).
Additional key features of Therapy+ include:
- Stepping using Therapy+ is not “trajectory based”. Users are more free to move of their own volition and are not guided along a pre-determined path or stepping sequence. For example, Users can step twice with their right leg if their first step was too short, or if they begin to feel off balance. Stepping does not have to be sequentially right and left as in Motion+.
- Indego Specialists have many options within the iPod depending on the User’s presentation and needs, including:
- The ability to make a User’s weak leg seem lighter and easier to move (Gravity Reduction),
- The ability to provide assistance at the hip or knee during swing phase (Active Swing),
- The ability to provide support at the knee in stance for those who may hyperextend or buckle into flexion (Stance Support),
- The ability to set therapy goals for stepping using an audible chime (Auditory Feedback).
How fast can a person walk using Therapy+? Users can walk as fast as they are able to initiate stepping, depending on their safety and their goals.
Variety of stability aid options
Persons using Indego with either Motion+ or Therapy+ have choices for stability aids, depending on their goals, abilities, and/or preferences. The type of stability aid used is determined by the Indego Specialist, and could include a rolling walker, rolling walker with platform attachments, forearm crutches or canes, to name a few. For example, some persons with complete SCI may use a walker in the home or when needing to carry items, but outside in the community may choose to use bilateral forearm crutches. Persons using Therapy+ often use a single sided forearm crutch or cane, but could also use other devices depending on their specific presentation.
Indego has several unique features to offer rehabilitation staff and Users. Indego Specialists may choose to use either Motion+, Therapy+, or both, depending on their patient’s needs and session goals. Motion+ offers a guided, predictable, posture based stepping pattern for those with more significant leg weakness. Therapy+, on the other hand, offers a muscle-initiated approach for persons who have the leg strength to initiate steps with or without active assistance offered during swing and or stance phases.
If you are interested in learning more about the Indego exoskeleton, please visit our website or give us a call at 1-844-846-3346.
This article was contributed by Clare Hartigan, PT, MPT. Clare is the Program Manager for Lower Extremity Robotics at The Virginia C Crawford Research Institute, Shepherd Center. Clare received her Bachelor of Science in Biology, Cum Laude, from Bucknell University in 1986 and a Master in Physical Therapy, Highest Honor, from Emory University in 1989. She has been working in the field of neurologic rehabilitation her entire career. Since 1991, she has been employed at Shepherd Center and served multiple roles as a clinician, supervisor/manager and researcher. Her work with exoskeletons began in 2010 trialing patients with Esko, ReWalk and Indego exoskeletons. Clare has conducted Indego research from 2010 to the present. Currently as a Certified Indego Instructor, Clare has travelled across the world educating and teaching others about exoskeleton technology. Clare is a member of the American Physical Therapy Association and the Neurologic Section.
Shepherd Center, located in Atlanta, Georgia, is a 152 bed, private, not-for-profit hospital specializing in medical treatment, research and rehabilitation for people with spinal cord injury, brain injury and multiple sclerosis.