(66 days)
The EksoNR™ is intended to perform ambulatory functions in rehabilitations under the supervision of a trained physical therapist for the following populations:
· Individuals with multiple sclerosis (upper extremity motor function of at least one arm).
• Individuals with acquired brain injury, including traumatic brain injury and stroke (upper extremity motor function of at least 4/5 in at least one arm).
· Individuals with spinal cord injuries at levels T4 to L5 (upper extremity motor function of at least 4/5 in both arms).
· Individuals with spinal cord injuries at levels of C7 to T3 (ASIA D with upper extremity motor function of at least 4/5 in both arms).
The therapist must complete a training program prior to use of the devices are not intended for sports or stair climbing
The Ekso is a powered motorized orthosis. It consists of a fitted metal brace that supports the legs, feet, and torso. It is worn via straps on the body, legs, and feet. Battery powered motors drive knee and hip joints. It has an integrated solid torso containing the computer and power supply. It has a hand-held user interface to specify settings and initiate steps. The Ekso is used with a cane, crutch, or walker.
Here's an analysis of the provided text, extracting information related to acceptance criteria and the study proving the device meets them. Please note that the document is a 510(k) summary for a medical device (exoskeleton), which focuses on demonstrating substantial equivalence to a predicate device rather than presenting a formal "acceptance criteria" table as might be seen for an AI/ML diagnostic tool. Therefore, some requested information may not be directly available or applicable in the provided context.
Overview:
The document clears the EksoNR powered lower extremity exoskeleton. The primary purpose of this 510(k) submission (K220988) is to expand the indications for use of the already cleared EksoNR (predicate device K200574) to include individuals with multiple sclerosis (MS). The device itself is essentially unchanged from the predicate.
Acceptance Criteria and Device Performance
Given this is a 510(k) for an updated indication for an existing medical device (exoskeleton) rather than an AI/ML diagnostic, the concept of "acceptance criteria" isn't framed as statistical thresholds for sensitivity/specificity. Instead, the acceptance criteria are implicitly that the device is safe and effective for the expanded population, demonstrating gait ambulation effectiveness and no new safety concerns in the specified population, thus maintaining substantial equivalence to the predicate.
Table of Acceptance Criteria (Implicit) and Reported Device Performance:
| Acceptance Criteria (Implicit) | Reported Device Performance |
|---|---|
| Safety: Device is safe for the expanded MS population (no new adverse events). | ADEMBI MS Study: "There were no falls or other adverse events reported." |
| Kessler MS Study: "There were no falls or other adverse events reported." | |
| Overall Conclusion: "The clinical data reported no adverse events demonstrating the device is safe on this patient population when used in accordance with existing labeling." | |
| Effectiveness: Device effectively facilitates gait ambulation in the expanded MS population. | ADEMBI MS Study (n=17-18): |
- TUG scores improved significantly: from 24s at baseline to 20.61s at completion of all Ekso sessions.
- Average walking speed maintained: from 0.69m/s at baseline to 0.66m/s at completion of all Ekso sessions.
- Average cognitive MOCA scores improved slightly.
Kessler MS Study (n=8):
- TUG scores improved significantly: from 16.99s at baseline to 14.15s at completion of all Ekso sessions.
- Average walking speed maintained: from 10.37s at baseline to 10.63s at completion of all Ekso sessions (note: units here are stated as 's' which is unusual for speed, likely a typo and referring to time for a specific distance or a different test. See 6MWT below).
- Symbol digit modalities test (cognition) improved.
- 6 minute walk test (6MWT) distance increased: from 279.65m to 294.69m.
- Average functional reach test distance increased.
Overall Conclusion: "The supporting clinical data demonstrating the use of the product with patients with multiple sclerosis (MS), show that the device effectively facilitates gait ambulation in the expanded patient population." |
| Substantial Equivalence: Device remains substantially equivalent to the predicate (K200574). | "This device and the previously cleared (predicate) device (K200574) are essentially the same products."
"The device is essentially unchanged from the current (predicate) device."
"The indications for use are identical to that of the predicate device, with the addition of the following: Individuals with multiple sclerosis..."
"When used as instructed, the device is as safe to use with a broader population of patients with neurological conditions to include the already cleared ABI and SCI population and this new MS population." |
Study Details
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Sample sizes used for the test set and the data provenance:
- Test Sets:
- ADEMBI MS Study: 18 subjects total used the Ekso. (n=17 for TUG post-testing, n=18 for others).
- Kessler MS Study: 9 subjects total used the Ekso. (n=8 for pre/post testing).
- Data Provenance: Not explicitly stated regarding country of origin, but described as "Single center, prospective parallel-assignment, single-blinded, randomized controlled study" for ADEMBI MS and "Single center, randomized study" for Kessler MS. This implies prospective data collection for these specific studies. No specific mention of retrospective vs. prospective is made for the original 7 studies that supported the predicate.
- Test Sets:
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Number of experts used to establish the ground truth for the test set and the qualifications of those experts:
- This is not an AI/ML diagnostic device where ground truth is established by expert readers interpreting images or data. For an exoskeleton, the "ground truth" for effectiveness is whether the patient can ambulate and improve functional scores, as measured by standardized clinical tests (TUG, 6MWT), and the "ground truth" for safety is the absence of adverse events/falls during supervised use.
- The device is used under the supervision of a "trained physical therapist." While not "experts establishing ground truth" in the diagnostic sense, their training and supervision are crucial for the device's safe and effective use and thus for the clinical outcomes.
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Adjudication method (e.g., 2+1, 3+1, none) for the test set:
- Not applicable. This is a functional device study, not an imaging diagnostic study requiring adjudication of image interpretations for ground truth. Clinical outcomes were measured directly using standardized tests and adverse events were reported.
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If a multi-reader multi-case (MRMC) comparative effectiveness study was done, If so, what was the effect size of how much human readers improve with AI vs without AI assistance:
- Not applicable. This is not an AI-assisted diagnostic tool. No MRMC study was performed or needed. The device (
EksoNR) is the primary intervention.
- Not applicable. This is not an AI-assisted diagnostic tool. No MRMC study was performed or needed. The device (
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If a standalone (i.e. algorithm only without human-in-the-loop performance) was done:
- Not applicable. The device is a physical exoskeleton designed for human-in-the-loop use under therapist supervision. It does not operate as a standalone algorithm.
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The type of ground truth used (expert consensus, pathology, outcomes data, etc.):
- Outcomes Data: The primary ground truth is established through measured clinical outcomes using validated functional assessment tools (e.g., Timed Up and Go (TUG) test, 6-minute walk test (6MWT), cognitive assessments like MOCA/Symbol Digit Modalities Test) and direct observation/reporting of adverse events (falls). This is outcomes-based evidence of safety and functional improvement.
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The sample size for the training set:
- Not applicable in the context of device approval for an exoskeleton. This is not an AI/ML algorithm that requires a "training set" in the computational sense. The device itself is "trained" during the manufacturing and design process, and the physical therapists are trained for its use.
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How the ground truth for the training set was established:
- Not applicable. As above, there is no AI/ML "training set" for this device. The physical therapists are trained users, and their "ground truth" would be established through their professional education, experience, and the specific training program provided for the EksoNR device.
§ 890.3480 Powered lower extremity exoskeleton.
(a)
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.(b)
Classification. Class II (special controls). The special controls for this device are:(1) Elements of the device materials that may contact the patient must be demonstrated to be biocompatible.
(2) 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.
(3) Appropriate software verification, validation, and hazard analysis must be performed.
(4) Design characteristics must ensure geometry and materials composition are consistent with intended use.
(5) Non-clinical performance testing must demonstrate that the device performs as intended under anticipated conditions of use. Performance testing must include:
(i) Mechanical bench testing (including durability testing) to demonstrate that the device will withstand forces, conditions, and environments encountered during use;
(ii) Simulated use testing (
i.e., cyclic loading testing) to demonstrate performance of device commands and safeguard under worst case conditions and after durability testing;(iii) Verification and validation of manual override controls are necessary, if present;
(iv) The accuracy of device features and safeguards; and
(v) Device functionality in terms of flame retardant materials, liquid/particle ingress prevention, sensor and actuator performance, and motor performance.
(6) 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:
(i) Level of supervision necessary, and
(ii) Environment of use (
e.g., indoors and/or outdoors) including obstacles and terrain representative of the intended use environment.(7) A training program must be included with sufficient educational elements so that upon completion of training program, the clinician, user, and companion can:
(i) Identify the safe environments for device use,
(ii) Use all safety features of device, and
(iii) Operate the device in simulated or actual use environments representative of indicated environments and use.
(8) Labeling for the Physician and User must include the following:
(i) 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.
(ii) Specific instructions and the clinical training needed for the safe use of the device, which includes:
(A) Instructions on assembling the device in all available configurations;
(B) Instructions on fitting the patient;
(C) Instructions and explanations of all available programs and how to program the device;
(D) Instructions and explanation of all controls, input, and outputs;
(E) Instructions on all available modes or states of the device;
(F) Instructions on all safety features of the device; and
(G) Instructions for properly maintaining the device.
(iii) Information on the patient population for which the device has been demonstrated to have a reasonable assurance of safety and effectiveness.
(iv) Pertinent non-clinical testing information (
e.g., EMC, battery longevity).(v) A detailed summary of the clinical testing including:
(A) Adverse events encountered under use conditions,
(B) Summary of study outcomes and endpoints, and
(C) 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).