FDA-510(K) -Human Factor Engineering/Usability Protocol

[srinu]

Hello Friends ,
I need a your thoughts or any experience about my questions.

1. Cadaver Accuracy / Performance Testing
   
   • Could you please confirm that Korean orthopedic surgeons—who have extensive experience with surgical navigation systems commonly used in the United States and who have been trained on our AR system—are acceptable for conducting the technical cadaver accuracy and performance evaluation?
2. Human Factors Validation (Summative HFE Study)
   We also understand that Human Factors Validation should involve test participants who represent the actual intended U.S. users.
   
   • Could you clarify whether this means that U.S.-licensed surgeons must perform the Human Factors Validation, even if Korean surgeons are technically proficient and experienced with U.S.-approved navigation platforms?
   • If Korean surgeons have documented training, extensive U.S.-system experience, and can perform all critical tasks realistically, would they still not be considered representative of intended U.S. users?
   • Could you please clarify whether this evaluation may be performed using sawbone models, or if it is necessary to conduct the testing on cadaver specimens?
3. Combined Studies
   For efficiency and consistency, we are considering a combined cadaver study that evaluates both technical accuracy and Human Factors critical tasks.
   
   • If such a combined study is conducted, must the participants be U.S.-licensed surgeons for the entire combined protocol, or is it acceptable to include Korean surgeons for the technical accuracy portion while ensuring that U.S.-representative surgeons perform the Human Factors portion?

 

[RA-QA&Cyber]

Considerations for your technical performance testing and Human Factors Validation will differ, as the expectations for user representativeness differ significantly between the two. For cadaver based accuracy and performance testing, FDA’s primary interest is in the quality of the methods, the measurement approach, and the repeatability of the results. The licensure status of the individuals performing these procedures is not usually a determining factor. If Korean orthopedic surgeons are highly experienced with navigation systems commonly used in the United States, have been fully trained on your AR system, and can execute the protocol consistently, they are generally acceptable for the technical accuracy portion of the study.

Human Factors Validation (summative HFE), however, is treated very differently. FDA is explicit that this validation must be conducted using participants who truly represent the intended U.S. user population. Based on my experience that typically means U.S licensed surgeons or surgeons who actively practice within U.S. clinical workflows and conditions. Even if Korean surgeons have extensive experience with U.S. approved navigation platforms and have documented training, they would not normally be considered representative users for the summative HFE component. This is because Human Factors Validation is not simply about technical proficiency it is about evaluating real-world use risks and workflow alignment specific to the U.S. clinical environment. However, some exceptions depend on your case.

Regarding study materials, the need for cadavers versus sawbone models depends on the purpose of the evaluation. For Human Factors Validation, FDA’s focus is on whether participants can realistically perform the critical tasks and whether potential use-related hazards are identified and mitigated. High-fidelity models or sawbones can often be acceptable for this purpose, provided they adequately represent the steps required to use the device. For accuracy or performance testing, sawbones typically do not offer the anatomical realism needed to validate true surgical accuracy, so cadavers are usually preferred for that portion.

If you choose to combine the cadaver accuracy study with the Human Factors Validation tasks in a single protocol, that approach can be workable as long as the requirements for each study type are clearly separated. Korean surgeons may participate in the technical accuracy portion without issue. However, only U.S. representative surgeons should perform the Human Factors critical tasks. I think as long as the protocol clearly distinguishes the two components and ensures that the Human Factors portion is conducted exclusively by the appropriate user group, FDA generally accepts combined study designs of this type.

 

[srinu]

Thank you for your detailed explanation @ (RA-QA& Cyber)

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Our device is an Augmented Reality–based Navigation System (AR System) intended for use in knee replacement surgery. I appreciate the clarity you have provided so far; however, I still have a few remaining questions. I have attached the FDA deficiency letter for your reference.


According to the FDA’s comments, they require both a performance accuracy evaluation and a human factors/usability validation. In our submission, we did not conduct cadaver-based verification testing; instead, we performed a human factors/usability study using sawbone models with three Korean surgeons.


My main concerns are as follows:

1. Based on the FDA’s expectations, it appears that sawbone models may be acceptable for certain usability elements, but the number of participants and the representativeness of those participants may not satisfy FDA requirements.
2. I would like to confirm your understanding of the FDA’s position regarding the need for cadaver-based accuracy testing versus sawbone-based studies.
3. Could you please review the attached FDA letter and share your interpretation, particularly regarding participant requirements, sample type expectations, and whether our current usability study would be considered insufficient?

Your insights will be extremely helpful in resolving my confusion and ensuring that we move forward in full alignment with FDA expectations. Thank you in advance for your guidance.

 

[Ed Panek]

Cadaver use is often acceptable for IDE work. To be certain request a meeting with FDA. Tell them your plan. Ask if this plan aligns with their expectations. They cant consult but they can say if your plan is in line with what they expect/require.

You may be able to FOIA this informtaion from competitors submission. The cost is minimal. Oftentimes manufacturers will provide a pdf of who/what/where their device has been tested clinically. Probably in the marketing section.