PROFEMUR® MODULAR FEMORAL NECK

Additional Manufacturer Narrative

THE ALLEGED COMPLAINT COULD NOT BE CONFIRMED. MPO RECEIVED A LEGAL FILE THAT ALLEGES THE PROFEMUR TITANIUM SHORT MODULAR NECK WAS FOUND TO HAVE CORRODED AFTER BEING REVISED APPROXIMATELY 171 MONTHS AFTER THE INDEX OPERATION DUE TO A DESCRIBED CUP LOOSENING. THE PATIENT WAS IMPLANTED WITH BILATERAL TOTAL HIP CONSTRUCTS CONTAINING CERAMIC-ON POLYETHYLENE BEARINGS AND A PROFEMUR TITANIUM MODULAR NECK. CERAMIC-ON-METAL ARTICULATION WAS BEING STUDIED THROUGH AN INVESTIGATIONAL DEVICE EXEMPTION (IDE), AND THE SURGERY DATES AND IMPLANTING SURGEON WERE CONFIRMED TO FALL WITHIN TIMEFRAMES OF THE STUDY. ANY IMPLANTATIONS OF CONSERVE BCH HEADS IN COMBINATION WITH CONSERVE CUPS WOULD BE OFF LABEL USAGE. THE EXPLANTED DEVICES HAVE NOT BEEN RETURNED TO MPO FOR INVESTIGATION. FURTHERMORE, MPO HAS NOT RECEIVED ANY RADIOGRAPHS, IMAGES, OR OPERATIVE NOTES TO CONFIRM THE ALLEGED CUP LOOSENING OR TO EVALUATE THE MODULAR NECK. IMAGES ARE INCLUDED IN THE PROVIDED LEGAL DOCUMENTATION, BUT THE IMAGES ARE NOT OF SUFFICIENT QUALITY TO EVALUATE. REVIEW OF THE DEVICE HISTORY RECORD (DHR) FOR THE SUBJECT MANUFACTURING LOTS INDICATES THAT THESE PRODUCTS MET ALL ESTABLISHED ACCEPTANCE CRITERIA THROUGHOUT MANUFACTURING PROCESSES. MPO HAS NOT RECEIVED ANY OTHER COMPLAINT REPORTS INVOLVING THE SUBJECT MANUFACTURING LOT, PHA01202 LOT 0601154069. THE CURRENT MICROPORT HIP SYSTEMS PACKAGE INSERT LISTS "DISLOCATION, MIGRATION AND/OR SUBLUXATION OF PROSTHETIC COMPONENTS FROM IMPROPER POSITIONING, TRAUMA, LOSS OF FIXATION AND/OR MUSCLE AND FIBROUS TISSUE LAXITY" AND "REACTIONS TO WEAR DEBRIS THAT MAY LEAD TO HISTOLOGICAL REACTIONS, PSEUDOTUMOR AND ASEPTIC LYMPHOCYTIC VASCULITIS-ASSOCIATED LESIONS (ALVAL)" AS POSSIBLE ADVERSE EFFECTS OF TOTAL HIP ARTHROPLASTY. THIS PACKAGE INSERT ALSO STATES: "ALWAYS FOLLOW THE RECOMMENDED SURGICAL TECHNIQUE. FAILURE TO ADHERE TO THE ADVISED ASSEMBLY INSTRUCTIONS MAY HAVE POTENTIAL TO INCREASE RISK OF FRETTING CORROSION, FATIGUE FRACTURE OR DISASSOCIATION OF THE PRODUCT. PRIOR TO ASSEMBLY, SURGICAL DEBRIS AND FLUID MUST BE CLEANED FROM THE INTERIOR OF THE FEMALE SEAT TO ENSURE PROPER LOCKING. ENSURE COMPONENTS ARE FIRMLY SEATED TO PREVENT DISASSOCIATION. THE FEMORAL HEAD, NECK TAPER OF THE FEMORAL COMPONENT, MODULAR NECK TAPERS, BODY TAPER, FEMALE SEAT OF THE PROXIMAL BODY MUST BE CLEAN AND DRY BEFORE ASSEMBLY. IMPACT ACCORDING TO THE RECOMMENDED SURGICAL TECHNIQUE. SCRATCHING OF FEMORAL HEADS, MODULAR NECKS AND PROXIMAL AND DISTAL STEM TAPERS SHOULD BE AVOIDED. REPEATED ASSEMBLY AND DISASSEMBLY OF THESE COMPONENTS COULD COMPROMISE THE LOCKING ACTION OF THE TAPER JOINT." THE POTENTIAL FOR MICROMOTION CAN RESULT IN PITTING FROM CREVICE CORROSION FROM YEARS OF CYCLIC LOADING. INVESTIGATION OF TITANIUM MODULAR NECK FRACTURES THROUGH MPO CAPA ACTIONS DETERMINED THE FOLLOWING FINDINGS REGARDING OBSERVED FRACTURE OCCURRENCES: "BASED ON OUR ANALYSIS AND TESTING, WE HAVE IDENTIFIED BOTH PATIENT-RELATED AND SURGICAL-RELATED FACTORS THAT CONTRIBUTE TO THE FRACTURE OF PROFEMUR® MODULAR NECKS. PATIENT-RELATED FACTORS INCLUDE HEAVY WEIGHT AND HIGH LEVELS OF ACTIVITY. SURGICAL-RELATED FACTORS INCLUDE THE ASSEMBLY OF THE MODULAR NECK TO THE STEM AND THE SELECTION OF THE LENGTH OF THE MODULAR NECK/FEMORAL HEAD COMBINATION, TYPICALLY REFERRED TO AS 'OFFSET.' ALTHOUGH RARE, IT IS POSSIBLE THAT STRESSES PRODUCED AT THE MODULAR NECK/ STEM TAPER INTERFACE BY HEAVY AND/OR HIGHLY ACTIVE PATIENTS WITH PREDOMINANTLY LONGER OFFSETS CAN EXCEED THE FATIGUE STRENGTH OF THE MODULAR NECK, RESULTING IN FRACTURE. IMPROPER ASSEMBLY OF THE MODULAR NECK TO THE STEM INCREASES THE RISK OF FRACTURE." SHORT TITANIUM MODULAR NECKS HAVE DISPLAYED A LOWER FRACTURE COMPLAINT RATE COMPARED TO LONG AND X-LONG TITANIUM MODULAR NECKS. LONG AND X-LONG MODULAR NECKS HAVE SINCE BEEN VOLUNTARILY RECALLED IN THE REPORTING COUNTRY THROUGH MPO REFERENCE DISTRIBUTED PRODUCT RISK ASSESSMENT (DPRA) #(B)(4). FURTHERMORE, AN ENGINEERING REPORT, REFERENCE NUMBER, WAS COMPLETED TO ASSESS THE POTENTIAL RISKS ASSOCIATED WITH CONSERVE BCH HEADS AND MODULAR TAPER CONNECTIONS. AS PART OF THIS TESTING, ALL SPECIMENS WITHSTOOD 1-MILLION CYCLES AT ISO LOAD VALUES WITHOUT NECK FRACTURE OR EVIDENCE OF EXCESSIVE FRETTING. THERE WERE NOT ANY TRENDS IDENTIFIED FOR THIS ITEM AND FAILURE PER MPO TRENDING PROCEDURES. NO ADDITIONAL ACTIONS ARE DEEMED NECESSARY AT THIS TIME. MPO WILL CONTINUE TO MONITOR THIS FAILURE TYPE THROUGH COMPLAINT TRACKING.

Additional Manufacturer Narrative

THIS EVENT WILL BE UPDATED ONCE THE INVESTIGATION IS COMPLETE. TRENDS WILL BE EVALUATED.

Description of Event or Problem

ALLEGEDLY, PATIENT'S LEFT HIP WAS A SUSPECTED LOOSE ACETABULAR COMPONENT. UPON A POST-SURGERY NON-DESTRUCTIVE CT EXAMINATION OF THE DEVICES REMOVED FROM PATIENT'S LEFT HIP IT WAS FOUND THAT THE MODULAR NECK OF THAT LEFT HIP HAD CORRODED AT THE NECK-STEM JUNCTION AND WAS IN THE PROCESS OF FRACTURING.