GMK TOTAL KNEE SYSTEM

Additional Manufacturer Narrative

R&D ANALYSIS REVISION SURGERY WAS PERFORMED APPROXIMATELY 4 YEARS AND 9 MONTHS AFTER THE PRIMARY PROCEDURE DUE TO REPORTED FEMORAL COMPONENT ASEPTIC LOOSENING. ACCORDING TO THE OPERATING SURGEON, THE PALACOS BONE CEMENT USED DURING THE PRIMARY PROCEDURE ADHERED TO THE PATIENT'S BONE BUT NOT TO THE IMPLANTED SENSITIN FEMORAL COMPONENT. DURING THE REVISION PROCEDURE, THE IMPLANTED GMK SPHERE SENSITIN PROSTHESIS WAS REVISED TO A GMK HINGE SENSITIN SYSTEM. THE REVISION SURGERY WAS COMPLETED SUCCESSFULLY. REVIEW OF THE AVAILABLE PHOTOGRAPHIC DOCUMENTATION INDICATES THE ABSENCE OR MINIMAL RESIDUALS OF BONE CEMENT WITHIN THE CEMENT POCKETS OF THE EXPLANTED FEMORAL AND TIBIAL COMPONENTS. BASED SOLELY ON THE AVAILABLE PHOTOGRAPHIC DOCUMENTATION, NO FURTHER TECHNICAL ASSESSMENT CAN BE PERFORMED. SUBOPTIMAL CEMENT FIXATION MAY RESULT FROM MULTIPLE FACTORS, MOST OF WHICH ARE UNRELATED TO THE DEVICE ITSELF. THESE FACTORS MAY INCLUDE, BUT ARE NOT LIMITED TO, CEMENT PREPARATION AND HANDLING, CEMENTATION TECHNIQUE, IMPLANT SEATING, INTRAOPERATIVE TEMPERATURE CONDITIONS, CEMENT CURING TIME, AND THE PRESENCE OF BLOOD, SALINE, OR OTHER FLUIDS AT THE CEMENT-IMPLANT INTERFACE. BASED ON THE INFORMATION CURRENTLY AVAILABLE, NO CONCLUSIVE EVIDENCE HAS BEEN IDENTIFIED TO DETERMINE A DEFINITIVE ROOT CAUSE. FURTHERMORE, THERE IS NO EVIDENCE INDICATING A MANUFACTURING DEFECT, MATERIAL NONCONFORMITY, OR DEVICE MALFUNCTION ASSOCIATED WITH THE IMPLANTED COMPONENTS. BATCH REVIEW PERFORMED ON (B)(6) 2026. GMK-SPHERE 02.12.0705L FEM COMPONENT CEMENTED TINBN COATED 5L (K202684) LOT. 174165: (B)(4) ITEMS MANUFACTURED AND RELEASED ON 18-DEC-2017. EXPIRATION DATE: 2022-DEC-06. NO ANOMALIES FOUND RELATED TO THE PROBLEM. TO DATE, (B)(4) ITEMS OF THE SAME LOT HAVE BEEN SOLD WITH NO SIMILAR REPORTED EVENTS DURING THE PERIOD OF REVIEW. GMK-SPHERE 02.12.0413FL TIBIAL INSERT - FLEX S4L - 13 MM (K140826) LOT. 1900376: (B)(4) ITEMS MANUFACTURED AND RELEASED ON 25-APR-2019. EXPIRATION DATE: 2024-APR-10. NO ANOMALIES FOUND RELATED TO THE PROBLEM. TO DATE, (B)(4) ITEMS OF THE SAME LOT HAVE BEEN SOLD WITH NO SIMILAR REPORTED EVENTS DURING THE PERIOD OF REVIEW. ROOT CAUSE: BASED ON THE AVAILABLE INFORMATION, NO DEFINITIVE ROOT CAUSE CAN BE ESTABLISHED. THE EVENT MAY BE RELATED TO SUBOPTIMAL CEMENT FIXATION, POTENTIALLY ASSOCIATED WITH CASE-SPECIFIC INTRAOPERATIVE FACTORS SUCH AS CEMENT HANDLING, CEMENTATION TECHNIQUE, IMPLANT SEATING, CURING TIME, OR THE PRESENCE OF FLUIDS AT THE CEMENT¿IMPLANT INTERFACE. NO MANUFACTURING DEFECT, MATERIAL NONCONFORMITY, OR DEVICE MALFUNCTION WAS IDENTIFIED.

Description of Event or Problem

REVISION SURGERY DUE TO FEMORAL COMPONENT LOOSENING AFTER ABOUT 4 YEARS AND 9 MONTHS FROM PRIMARY. THE SURGEON NOTED THAT THE PLACOS CEMENT THAT WAS USED IN THE PRIMARY ON THE SENSITIN IMPLANTS ADHERED TO THE PATIENT`S BONE BUT NOT TO THE IMPLANT. THE SURGEON REVISED THE GMK-SPHERE 5L TINBN COATED FEMORAL COMPONENT TO GMK-HINGE SIZE 4 L FEMORAL COMPONENT, REVISED THE SIZE 4 13MM FLEX INSERT TO A SIZE 3 17MM GMK-HINGE INSERT, AND REVISED THE GMK-SPHERE 4L FIXED TIBIAL TRAY TO A 3L GMK-HINGE FIXED TINBN COATED TIBIAL TRAY. THE SURGERY WAS COMPLETED SUCCESSFULLY.