A_Archipenko
Registered
Hello,
I ran into an interesting discussion lately and would like to hear your opinions.
In my experience, orthopedic medical device manufacturers have been successful with regulatory bodies (EU notified bodies, as well as FDA) by evaluating product families for biocompatibility.
Example:
1. Bone screws that are manufactured in identical ways, have the same design and indication, but differ only in size (length) and shape (thread count).
2. Bone plates that are manufactured in identical ways and have the same design and indication, but differ only in size (length) and shape (amount of threaded holes that receive bone screws).
Regarding worst-case device selection for biocompatibility assessment, the largest device would have been chosen since it has the highest design complexity in regards of thread count (screws), as well as threaded holes (plates). The rational behind this was that the more threads a device has, the risk of effectively cleaning the device (and leaving residues from the manufacturing process behind adversely affecting biocompatibility) would increase.
Any toxicological data could therefore be applied to smaller device sizes since they are lower risk.
I was now wondering if anyone used the opposite approach by using the smallest device and scaling data up to larger devices?
Thinking about this, my concern would be that it might be hard to rationalize the cleanability (and therefore removal of any manufacturing residuals) of the larger devices which have more threads, especially since usually the thread count (screws) or hole count (plates) does not scale linearly to the device size.
Another issue would be if the largest device has been tested, but the manufacturer now wants to expand the product family with even larger devices. What approach to biocompatibility risk assessment would one use in such a case?
Happy to hear any insights!
Archi
I ran into an interesting discussion lately and would like to hear your opinions.
In my experience, orthopedic medical device manufacturers have been successful with regulatory bodies (EU notified bodies, as well as FDA) by evaluating product families for biocompatibility.
Example:
1. Bone screws that are manufactured in identical ways, have the same design and indication, but differ only in size (length) and shape (thread count).
2. Bone plates that are manufactured in identical ways and have the same design and indication, but differ only in size (length) and shape (amount of threaded holes that receive bone screws).
Regarding worst-case device selection for biocompatibility assessment, the largest device would have been chosen since it has the highest design complexity in regards of thread count (screws), as well as threaded holes (plates). The rational behind this was that the more threads a device has, the risk of effectively cleaning the device (and leaving residues from the manufacturing process behind adversely affecting biocompatibility) would increase.
Any toxicological data could therefore be applied to smaller device sizes since they are lower risk.
I was now wondering if anyone used the opposite approach by using the smallest device and scaling data up to larger devices?
Thinking about this, my concern would be that it might be hard to rationalize the cleanability (and therefore removal of any manufacturing residuals) of the larger devices which have more threads, especially since usually the thread count (screws) or hole count (plates) does not scale linearly to the device size.
Another issue would be if the largest device has been tested, but the manufacturer now wants to expand the product family with even larger devices. What approach to biocompatibility risk assessment would one use in such a case?
Happy to hear any insights!
Archi