Identification. A powered lower extremity exoskeleton is a prescription device that is composed of an external, powered, motorized orthosis that is placed over a person's paralyzed or weakened limbs for medical purposes.

Classification. Class II (special controls). The special controls for this device are:

Elements of the device materials that may contact the patient must be demonstrated to be biocompatible.

Appropriate analysis/testing must validate electromagnetic compatibility/interference (EMC/EMI), electrical safety, thermal safety, mechanical safety, battery performance and safety, and wireless performance, if applicable.

Appropriate software verification, validation, and hazard analysis must be performed.

Design characteristics must ensure geometry and materials composition are consistent with intended use.

Non-clinical performance testing must demonstrate that the device performs as intended under anticipated conditions of use. Performance testing must include:

Mechanical bench testing (including durability testing) to demonstrate that the device will withstand forces, conditions, and environments encountered during use;

Simulated use testing (i.e., cyclic loading testing) to demonstrate performance of device commands and safeguard under worst case conditions and after durability testing;

Verification and validation of manual override controls are necessary, if present;

The accuracy of device features and safeguards; and

Device functionality in terms of flame retardant materials, liquid/particle ingress prevention, sensor and actuator performance, and motor performance.

Clinical testing must demonstrate a reasonable assurance of safe and effective use and capture any adverse events observed during clinical use when used under the proposed conditions of use, which must include considerations for:

Level of supervision necessary, and

Environment of use (e.g., indoors and/or outdoors) including obstacles and terrain representative of the intended use environment.

A training program must be included with sufficient educational elements so that upon completion of training program, the clinician, user, and companion can:

Identify the safe environments for device use,

Use all safety features of device, and

Operate the device in simulated or actual use environments representative of indicated environments and use.

Labeling for the Physician and User must include the following:

Appropriate instructions, warning, cautions, limitations, and information related to the necessary safeguards of the device, including warning against activities and environments that may put the user at greater risk.

Specific instructions and the clinical training needed for the safe use of the device, which includes:

Instructions on assembling the device in all available configurations;

Instructions on fitting the patient;

Instructions and explanations of all available programs and how to program the device;

Instructions and explanation of all controls, input, and outputs;

Instructions on all available modes or states of the device;

Instructions on all safety features of the device; and

Instructions for properly maintaining the device.

Information on the patient population for which the device has been demonstrated to have a reasonable assurance of safety and effectiveness.

Pertinent non-clinical testing information (e.g., EMC, battery longevity).

A detailed summary of the clinical testing including:

Adverse events encountered under use conditions,

Summary of study outcomes and endpoints, and

Information pertinent to use of the device including the conditions under which the device was studied (e.g., level of supervision or assistance, and environment of use (e.g., indoors and/or outdoors) including obstacles and terrain).