The Complex Process of Using the Interconnected Knee Arthroplasty Device Clearance Pathway.

Area of Science:

• Orthopedic device regulation and safety
• Medical device clearance pathways
• Total knee arthroplasty (TKA) device evolution

Background:

• The US Food and Drug Administration (FDA) has utilized a 3-tiered device classification system since 1976, based on consumer safety risk.
• The 510(k) premarket pathway allows clearance of orthopedic devices by demonstrating substantial equivalence to previously cleared 'predicate ancestors'.

Purpose of the Study:

• To trace the predicate lineage of modern total knee arthroplasty (TKA) devices cleared through the 510(k) pathway.
• To identify TKA devices cleared via 510(k) that are substantially equivalent to devices subsequently recalled by the FDA.

Main Methods:

• Searched FDA databases (May 1976–May 2021) using knee arthroplasty Classification Process Codes to identify TKA devices.
• Analyzed direct and indirect substantial equivalence claims to trace predicate device ancestry for 1220 relevant devices.
• Correlated cleared devices with FDA recall data to assess links to recalled predicate devices.

Main Results:

• Of 1220 knee devices, 1214 (99.5%) were cleared via the 510(k) pathway; 217 (17.9%) have been recalled.
• 204 devices (16.8%) are linked to at least one recalled predicate device through generational substantial equivalence claims.
• 90 devices (7.4%) have a direct link to a recalled predicate device.

Conclusions:

• The clearance of most TKA devices relies on a complex network of substantial equivalence to older predicates, often spanning decades with design modifications.
• A significant number of currently marketed TKA devices are linked to predicates that have since been recalled by the FDA.
• Findings suggest a need for updated regulatory strategies to enhance patient safety while managing regulatory burdens in medical device clearance.