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WARNING LETTER

Red Oak Instruments, LLC MARCS-CMS 692368 —

Delivery Method:
VIA Electronic Mail
Product:
Medical Devices
Recipient:
Recipient Name
Mr. William C. Paske, PhD
Recipient Title
Owner
Red Oak Instruments, LLC

3331 Prosperity Court
Missouri City, TX 77459
United States

Issuing Office:
Center for Devices and Radiological Health

United States

WARNING LETTER
CMS # 692368

February 21, 2025

Mr. William C. Paske, PhD, Owner
Red Oak Instruments, LLC
3331 Prosperity Court
Missouri City, TX 77459

Dear Mr. Paske:

During an inspection of your firm, Red Oak Instruments, LLC (Red Oak, ROI, or “the firm”), located in Missouri City, Texas, on July 15, 2024, through July 26, 2024, an investigator from the United States Food and Drug Administration (FDA) determined that your firm is a manufacturer and distributor of the AC Powered Dynamometer RU-Fit (Model SR-3053) medical device. Under section 201(h) of the Federal Food, Drug, and Cosmetic Act (the Act), 21 U.S.C. § 321(h), these are devices intended for use in the diagnosis of disease or other conditions or in the cure, mitigation, treatment, or prevention of disease, or to affect the structure or function of the body.

We received your responses dated August 13, 2024, November 7, 2024, and February 5, 2025 concerning our investigator’s observations on the Form FDA 483 (FDA 483), List of Inspectional Observations, that was issued to your firm. We address the responses below, in relation to each of the noted violations, and any additional responses will be reviewed as part of your warning letter response.

Misbranded and/or Unapproved Device Violations

FDA has reviewed your website at https://www.redoakinstruments.com on January 15, 2025, and determined that the RU-FIT (Model SR-3053) is adulterated under section 501(f)(1)(B) of the Act, 21 U.S.C. § 351(f)(1)(B), because your firm does not have an approved application for premarket approval (PMA) in effect pursuant to section 515(a) of the Act, 21 U.S.C. § 360e(a), or an approved application for an investigational device exemption (IDE) under section 520(g) of the Act, 21 U.S.C. § 360j(g) for the device as described and marketed. The RU-FIT (Model SR-3053) is also misbranded under section 502(o) the Act, 21 U.S.C. § 352(o), because your firm introduced or delivered for introduction into interstate commerce for commercial distribution this device with major changes or modifications to the intended use without submitting a new premarket notification to FDA as required by section 510(k) of the Act, 21 U.S.C. § 360(k), and 21 CFR 807.81(a)(3)(ii).

Devices classified under 21 CFR 888.1240 AC-powered dynamometer are exempt from premarket notification unless they exceed the limitations on exemption at 21 CFR 886.9(a). However, there is evidence that the RU-FIT (Model SR-3053) is intended for uses that are different from those of legally marketed devices classified under 21 CFR 888.1240 AC-powered dynamometer. Generic devices of this type are intended “to assess neuromuscular function or degree of neuromuscular blockage by measuring, with a force transducer (a device that translates force into electrical impulses), the grip-strength of a patient's hand.” 21 CFR 888.1240 However, your firm is marketing the RU-FIT (Model SR-3053) for a different intended use, namely the device is intended to screen for possible mild traumatic brain injury (mTBI), also known as concussion.

Examples include:

From the RU-Fit (Model SR-3053) User Guide
• This device is intended to screen for possible head injuries in the cases of head impact where there is not any visible blood, other than minor scraps [sic].
• The SR-3053 should be used…to compare recognition and choice reaction times of an injured or non-injured individual.

From the RU-Fit (Model SR-3053) Training Presentation

  • “Head Impact Trauma Screen: Analysis”
  • “Recognition reaction times for the small, index fingers and thumb”
  • “Cognitive reaction times for the small, index fingers and thumb”
  • “Summary Sheet For Concussive Impact”

From the Red Oak Instruments website (https://www.redoakinstruments.com)

  • Since denial is a strong symptom of mTBI subjects, the necessary compliance is not always achievable. A better technology is needed. RedOak Instruments provides the needed technology.
  • Physicians, clinicians, military medics, emergency responders, coaches and trainers can now immediately evaluate the severity of a bloodless head injury on-site. This is especially important in the case of mTBI and other head injuries because denial of injury is a common reaction, and visible symptoms may be difficult to assess in the absence of visible blood such that the injury goes undetected.
  • RedOak Instruments, LLC is a USA based biomechanical and software-based company which provides objective physiological measurements to screen for injuries, ailments and to monitor recovery. The test will document the reduction or improvement of factors related to head injury including fine motor control, coordination and reaction time.
  • Additionally, ROI's RU-Fit model SR-3053 SensoKinetoGram offers objective monitoring for sports training programs to aid trainers and coaches as they develop and improve the coordination and reaction times of their athletes. 
  • Test the hands and protect the brain.

You state that “all systems are FDA cleared…” however you device is not cleared as presently marketed.

Assessments of reaction time and cognitive function are not measurements of the grip-strength of a patient’s hand, and screening for, or detection of, mTBI is a neurological evaluation following head injury, not an assessment of neuromuscular function following hand injury.

Further, we note that the RU-FIT (Model SR-3053) was previously cleared under K012492 with the following indications:

Any situation where the hand grip or pinch strength would be a valuable piece of data in the evaluation of a person who has sustained an injury or suffers a disease of his/her hand(s).

  • To measure grip or pinch strength in an injured and uninjured hand.
  • To conduct pre-employment screening for physically demanding job activities.
  • To establish an industrial strength testing program in general, and to match the strength of workers to the strength demands of specific job duties in the workplace.

Thus, your firm’s promotion of the device provides evidence that the device is intended for to screen for possible mild traumatic brain injury (mTBI), also known as concussion, which would constitute a major change or modification to its intended use, for which your firm lacks clearance or approval.

For a device requiring premarket approval, the notification required by section 510(k) of the Act, 21 U.S.C. § 360(k), is deemed satisfied when a PMA is pending before the agency. 21 CFR 807.81(b). The kind of information that your firm needs to submit in order to obtain approval or clearance for the device is described on the Internet at http://www.fda.gov/MedicalDevices/DeviceRegulationandGuidance/HowtoMarketYourDevice/default.htm. The FDA will evaluate the information that your firm submits and decide whether the product may be legally marketed.

Medical Device Reporting Violations

Our inspection also revealed that your firm has failed to adequately develop, maintain, and implement written MDR procedures as required by 21 CFR 803.17. For example, during the inspection, the firm identified the document titled “Complaint MDR SOP ROI-000-0007,” dated 12/11/2019 as its written MDR procedure. After reviewing the procedure, the following deficiencies were noted:

1. Your procedure does not establish internal systems that provide for timely and effective identification, communication, and evaluation of events that may be subject to MDR requirements, as required by 21 CFR 803.17(a)(1). For example:

a. There are no definitions of what your firm will consider to be a reportable event under 21 CFR Part 803. The exclusion of definitions from 21 CFR 803.3 for the terms ‘become aware’, ‘caused or contributed’, ‘malfunction’, ‘MDR reportable event’, and ‘serious injury’, and the definition for the term ‘reasonably suggests’, found in 803.20(c)(1) may lead your firm to make an incorrect reportability decision when evaluating a complaint that may meet the criteria for reporting under 21 CFR 803.50(a).
b. Your procedure does not include instructions for how your firm will evaluate information about an event to make MDR reportability determinations in a timely manner.

2. Your procedure does not establish internal systems that provide for a standardized review process to determine when an event meets the criteria for reporting under this part, as required by 21 CFR 803.17(a)(2). For example,

a. There are no instructions for conducting an investigation of each MDR reportable event and evaluating the cause of the event.
b. Your procedure, as written, does not specify who makes the decision for reporting events to FDA.
c. The flowchart in your firm’s procedure does not reference a process for investigating events identified as MDRs to ensure that MDRs are submitted to FDA within the required reporting timeframes, as required under 21 CFR 803.17(a)(1).

3. Your procedure does not establish internal systems that provide for timely transmission of complete medical device reports, as required by 21 CFR 803.17(a)(3). Specifically, the procedure does not include:

a. Instructions for how to obtain and complete the FDA 3500A form.
b. The circumstances under which your firm must submit an initial 30 days, supplemental or follow-up, 5-day report and the requirements for such reports.
c. A process for submitting initial and supplement or follow-up reports to FDA in an electronic format that FDA can process, review and archive. Information about the Final Rule for eMDR and the eMDR set-up process can be found on the FDA website at: https://www.fda.gov/medical-devices/mandatory-reporting-requirements-manufacturers-importers-and-device-user-facilities/emdr-electronic-medical-device-reporting
d. How your firm will submit all information reasonably known to it for each event. Specifically, which sections of the 3500A will need to be completed to include all information found in your firm’s possession and any information that becomes available as a result of a reasonable follow up within your firm.

4. Your procedure does not describe how your firm will address documentation and record-keeping requirements, as required by 21 CFR 803.17(b), including:

a. Documentation of adverse event related information maintained as MDR event files.
b. Information that was evaluated to determine if an event was reportable.
c. Documentation of the deliberations and decision-making processes used to determine if a device-related death, serious injury, or malfunction was or was not reportable, as required under 21 CFR 803.18(b)(1)(i).
d. Systems that ensure access to information that facilitates timely follow-up and inspection by FDA.

A device is deemed to be misbranded under section 502(t)(2) of the Act, 21 U.S.C. § 352(t)(2), if there was a failure or refusal to furnish any material or information required by or under section 519 of the Act, 21 U.S.C. § 360i, which includes adverse event reports required under 21 CFR Part 803, respecting the device.

Additionally, based on our records, as of October 29, 2024, there is no evidence that your firm established an active Electronic Submissions Gateway (ESG) production account for the electronic submission of MDR reports. Information about the ESG can be found at: How to Enroll in eMDR Program | FDA.

The adequacy of your firm’s response dated August 13, 2024, cannot be determined at this time. Your firm’s response outlined plans to implement corrections and corrective actions, including creating an eMDR account and updating their MDR procedure. However, your firm did not provide documentation confirming the completion of these systemic corrective actions, including its revised MDR procedure, as they are still ongoing.

Quality System Regulation (QSR) Violations

Our inspection also revealed that the RU-Fit model SR-3053 is adulterated within the meaning of section 501(h) of the Act, 21 U.S.C. § 351(h), in that the methods used in, or the facilities or controls for, their manufacture, packing, storage, or installation are not in conformity with the current good manufacturing practice requirements of the Quality System regulation found at Title 21, Code of Federal Regulations (CFR), Part 820. These violations include, but are not limited to, the following:

1. Failure to adequately establish design change procedures as required by 21 CFR 820.30(i).

Specifically, you did not document a (b)(4). You also did not document the design verification of the (b)(4).

The adequacy of your firm’s responses cannot be determined at this time. Your firm stated that it will update your Design Procedures to clarify when an ECO must be validated, or not, including training and that hardware changes will be documented that were not previously. You also state that you have rewritten your procedures, updated ECO forms, and “begun” documenting previously undocumented modifications. However, you have not provided evidence of corrective actions to show how you document design changes to ensure they are in compliance with 21 CFR 820.30(i).

2. Failure of design verification to confirm that design output meets design input requirements as required by 21 CFR 820.30(f).

Specifically, your firm lacks a Development Procedure Form to document design verification as required by section 9.3 of your Design Control procedure. Your firm did not document an update of acceptance limits for the (b)(4) based on statistical test results in version 1.1 of your Test Plan.

The adequacy of your firm’s responses cannot be determined at this time. Your firm stated that it updated form ROI 001-0030-3 to show that the requisite measured uncertainties are within the specified range and that you (b)(4). Your firm stated that multiple calibration tests were carried out to demonstrate stability and that (b)(4) specifications are in the DMR and components used in manufacturing of (b)(4) are listed in the Inspection Acceptance Form. Your firm also stated it has (b)(4). However, your firm has not provided evidence of corrective actions to show how your design verification confirms that design output meets design input requirements.

3. Failure to establish device acceptance procedures as required by 21 CFR 820.80(d).

Specifically, you provided calibration test data but did not have a finished device acceptance procedure with complete product specifications.

The adequacy of your firm’s responses cannot be determined at this time. You state that manufacturer certificates and testing data will be appended to calibration data, and you will confirm (b)(4) specifications. However, you have not provided evidence of corrective actions as to how you will develop and maintain a device acceptance procedure to ensure that each production run, lot, or batch of finished devices meets acceptance criteria.

4. Failure to maintain device history record procedures as required by 21 CFR 820.184.

Specifically, your Device History Record procedure states that you will record production run data, but you did not have such data for 107 RU-Fit devices you manufactured. You only had a bill of materials (BOM) provided as a Device Master Record (DMR).

The adequacy of your firm’s responses cannot be determined at this time. You state that your data is available in excel charts and printed to pdf files. However, you have not provided evidence of the files stored electronically in your DMR folder.

5. Failure to perform quality audits as required by 21 CFR 820.22.

Specifically, your Internal Audit procedure states that you will conduct audits annually, but you did not have evidence of the performance of quality audits from 2018 to 2023.

The adequacy of your firm’s responses cannot be determined at this time. You state that you could not perform audits due to staffing and funding but that conducted an audit in December of 2024 and is in your form ROI 001-0024-0 as a pdf file. you will conduct and document an audit in 2024. However, you have not yet provided evidence of the conduct of the audit in December 2024.

6. Failure of management with executive responsibility to review the suitability and effectiveness of the quality system at defined intervals and with sufficient frequency as required by 21 CFR 820.20(c).

Specifically, your Management Responsibility procedure states that you will conduct reviews annually, but you did not have evidence of the performance of management reviews from 2018 to 2023.

The adequacy of your firm’s responses cannot be determined at this time. You state that you will update your Management Responsibility procedure and will conduct and document a review in 2024, including a minimum of one per quarter. However, you have not yet provided evidence of the conduct of your three review meetings stated as conducted since August 2024.

Your firm should take prompt action to address any violations identified in this letter. Failure to adequately address this matter may result in regulatory action being initiated by the FDA without further notice. These actions include, but are not limited to, seizure, injunction, and civil money penalties.

Other federal agencies may take your compliance with the FD&C Act and its implementing regulations into account when considering the award of federal contracts. Additionally, should FDA determine that you have Quality System regulation violations that are reasonably related to premarket approval applications for Class III devices, such devices will not be approved until the violations have been addressed. Should FDA determine that your devices or facilities do not meet the requirements of the Act, requests for Certificates to Foreign Governments (CFG) may not be granted.

Please notify this office in writing within fifteen business days from the date you receive this letter of the specific steps your firm has taken to address the noted violations, as well as an explanation of how your firm plans to prevent these violations, or similar violations, from occurring again. Include documentation of the corrections and/or corrective actions (which must address systemic problems) that your firm has taken. If your firm’s planned corrections and/or corrective actions will occur over time, please include a timetable for implementation of those activities. If corrections and/or corrective actions cannot be completed within fifteen business days, state the reason for the delay and the time within which these activities will be completed. Your firm’s response should be comprehensive and address any violations included in this Warning Letter. If you believe that your products are not in violation of the FD&C Act, include your reasoning and any supporting information for our consideration as part of your response.

Your firm’s response should be sent to: Jessica Mu, Assistant Director at CDRHEnforcement@fda.hhs.gov. Please include in the subject line, CMS case #692368 when replying. If you have any questions about the contents of this letter, please contact: Raymond W. Brullo, Compliance Officer at raymond.brullo@fda.hhs.gov.

Finally, you should know that this letter is not intended to be an all-inclusive list of the violations at your firm’s facility. It is your firm’s responsibility to ensure compliance with applicable laws and regulations administered by FDA. The specific violations noted in this letter and in the Inspectional Observations, FDA 483, issued at the close of the inspection may be symptomatic of serious problems in your firm’s manufacturing and quality management systems. Your firm should investigate and determine the causes of any violations and take prompt actions to address any violations and bring the products into compliance.

Sincerely,
/S/

RDML Sean Boyd, MPH, USPHS  
Director  
Office of Regulatory Programs  
Office of Product Evaluation and Quality
Center for Devices and Radiological Health

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