ALLOFIT-S ALLOCLASSIC, SHELL WITH POLAR SCREW PLUG, UNCEMENTED, 58/LL

Report

Report Number: 0009613350-2020-00338
Event Type: Injury
Date Received: July 24, 2020
Date of Event: July 8, 2020
Report Date: March 29, 2021
Manufacturer: ZIMMER SWITZERLAND MANUFACTURING GMBH
Product Code: KWA
PMA / PMN Number: N/A
Removal / Correction Number: N/A
Adverse Event: Yes
Product Problem: Yes
Report Source: Manufacturer report
Reporter Location: GM
Reporter Occupation: PHYSICIAN

Narratives

Additional Manufacturer Narrative · 0

INVESTIGATION RESULTS WERE MADE AVAILABLE. EVENT DESCRIPTION: IT WAS REPORTED THAT AN ALLOFIT SHELL AND AN ALLOFIT ALPHA INSERT WERE IMPLANTED IN THE RIGHT HIP ON (B)(6) 2020. THE INSERT DISLOCATED, LEAVING THE PATIENT WITH AN INSTABLE HIP JOINT, BARELY ABLE TO WALK. THE PATIENT WAS REVISED ON (B)(6) 2020. THE SHELL WAS ALSO REPLACED AS A NEW ALLOFIT INSERT COULD NOT BE ANCHORED WITHIN THE SHELL DURING REVISION SURGERY. REVIEW OF RECEIVED DATA: X-RAYS: A SINGLE AP INTRAOPERATIVE FLUOROSCOPIC IMAGE LABELED (B)(6) 2020, AN AP LOWER PELVIS AND A CROSS TABLE RIGHT HIP LABELED (B)(6) 2020 HAVE BEEN RECEIVED AND WERE REVIEWED BY A RADIOLOGIST. INITIAL FLUOROSCOPIC IMAGE DEMONSTRATES ANATOMIC ALIGNMENT OF THE RIGHT HIP ARTHROPLASTY. SUBSEQUENT IMAGES DEMONSTRATE LATERAL SUBLUXATION OF THE FEMORAL HEAD WITHIN THE ACETABULAR CUP WITHOUT FRANK DISLOCATION. THIS IS CONSISTENT WITH INTERVAL INSERT DISPLACEMENT. THERE IS NO FRACTURE OR EVIDENCE OF IMPLANT LOOSENING. BONE QUALITY IS OSTEOPENIC. SURGICAL REPORT: IMPLANTATION PROTOCOL, DATED (B)(6) 2020: DIAGNOSIS: FEMORAL NECK FRACTURE. TREATMENT: IMPLANTATION OF A HYBRID ENDOPROSTHESIS. LIST OF IMPLANTS: REF: 4268, LOT: 3010126 - ALLOFIT CUP 58/LL. REF: 01.00013.712, LOT: 3017962 - DURASUL INSERT LL/36. REF: 35.00.39-137, LOT: 3021648 - MÜLLER STEM LATERAL CEMENTED 13/75. REF: 01.01012.366, LOT: 3022367 - HEAD 36/M. REVISION REPORT, DATED (B)(6) 2020: DIAGNOSIS: LUXATION OF INSERT CONDITION AFTER HYBRID TEP RIGHT TREATMENT: REVISION OF RIGHT HIP WITH REPLACEMENT OF SHELL, INSERT AND HEAD INDICATION: CONDITION AFTER RIGHT HIP TEP AROUND 1 WEEK AGO DUE TO A FEMORAL NECK FRACTURE. SINCE 2 DAYS, THE PATIENT HAS BEEN COMPLAINING OF PAINFUL WEIGHT BEARING AND A CRACKING SOUND WHEN WALKING. RADIOGRAPHIC FOLLOW-UP SHOWS A DECENTERED HEAD, BUT NO TRUE DISLOCATION. DESCRIPTION OF PROCEDURE: ACCESS THROUGH OLD SCAR AND EXPOSURE OF THE INSERT, WHICH IS LUXATED MEDIOCAUDALLY, THE METAL HEAD IS STILL IN THE CUP. THE FEMORAL HEAD CAN BE DISLOCATED FROM THE CUP AND THE INSERT REMOVED. THE RELATIVELY DEEP SEATED ALLOFIT CUP IS NOW WELL EXPOSED AT ALL METAL EDGES AND AN IDENTICAL INSERT LL/36 IS INSERTED. DESPITE REPEATED ATTEMPTS, THE INSERT DOES NOT SEAT AND QUICKLY SHOWS DEFORMATION ON THE EDGES. THEREFORE, IT WAS DECIDED TO REPLACE THE CUP. AFTER REMOVING THE LOCKING SCREW, THE CUP CAN BE KNOCKED LOOSE WITH A CHISEL AND PULLED OUT. SUBSEQUENTLY, ACETABULAR FLOOR RECONSTRUCTION WITH TUTOGEN-SPONGIOSACHIPS. IMPLANTATION OF A LARGER ALLOFIT CUP 60/MM, A NEW INSERT MM/36 AND A NEW FEMORAL HEAD 36/M. PRODUCT EVALUATION: VISUAL EXAMINATION: THE ALLOFIT SHELL AND ONE ALLOFIT INSERT WERE RETURNED FOR EXAMINATION. THE LOT NUMBER ON THE RECEIVED POLYETHYLENE INSERT DOES NOT MATCH THE LOT NUMBER OF THE INSERT THAT WAS, ACCORDING TO THE SURGICAL PROTOCOL, IMPLANTED DURING INITIAL SURGERY ON (B)(6) 2020. BASED ON THE LOT MISMATCH AND THE VISUAL EXAMINATION DESCRIBED BELOW, IT IS ASSUMED THAT THE RETURNED INSERT IS THE INSERT THAT COULD NOT BE INSERTED INTO THE SHELL DURING REVISION SURGERY ON (B)(6) 2020 LEADING TO THE REMOVAL OF THE SHELL. THE DISLOCATED INSERT, IMPLANTED DURING THE INITIAL IMPLANTATION, HAS NOT BEEN RECEIVED. THE ANCHORING SURFACE OF THE SHELL HAS HARDLY ANY REMAINS OF BONE ATTACHMENTS. FURTHER, THE THREAD OF THE POLAR SCREW HOLE IS DEFORMED (WORN THREAD) AND PART OF IT HAS SHEARED OFF. ON THE INNER SHELL SURFACE, THE CHAMFER OF THE POLAR SCREW HOLE IS WORN. IN ADDITION, THE SURFACE AROUND TWO OUTER SCREW HOLES AND THE CHAMFER OF THE THIRD OUTER SCREW HOLE IS POLISHED AND SCRATCHED. FURTHER SCRATCHES CAN BE SEEN SPREAD OVER THE INNER SURFACE. THE RIM HAS SOME POLISHED, SCRATCHED AND INDENTED AREAS. ONE OF THE ANTI-ROTATION PINS (THE ONE CLOSER TO THE SCREW HOLES) IS MISSING. THE POLYETHYLENE INSERT HAS SCRATCHES AND SOME SHEARED OFF PARTS ON THE OUTER AND INNER SURFACES. FURTHERMORE, ONLY ONE PIN INDENTATION IS VISIBLE ON THE OUTER SURFACE AND A LESS PRONOUNCED INDENTATION AROUND 5 MM NEXT TO IT. IN ADDITION, ABOUT HALF OF THE POLAR PEG IS INDENTED. MEASUREMENTS: TO ENSURE THE SHELL HAS CORRECT DIMENSIONS, RELEVANT CHARACTERISTICS ACCORDING TO INSPECTION PLAN AND PRODUCT DRAWING WERE MEASURED WITH CALIPER Z 7568. CHARACTERISTIC NO. 16 FEATURE DIAMETER 56 +0.3/-0.3. SPECIFICATION: MAX. 56.30 MM; MIN. 55.70 MM. MEASURED VALUE: 55.93 MM. THE MEASURED DIAMETER IS WITHIN THE DEFINED SPECIFICATION. CHARACTERISTIC NO. 18 FEATURE HEIGHT 27.527 +0.2/-0.2. SPECIFICATION: MAX. 27.727 MM; MIN. 27.327 MM. MEASURED VALUE: 27.47 MM. THE MEASURED DIMENSION IS WITHIN THE DEFINED SPECIFICATION. REVIEW OF PRODUCT DOCUMENTATION: DEVICE PURPOSE: ALL INVOLVED DEVICES ARE INTENDED FOR TREATMENT. PRODUCT COMPATIBILITY: THE COMPATIBILITY CHECK WAS PERFORMED AND SHOWED THAT THE PRODUCT COMBINATION WAS APPROVED BY ZIMMER BIOMET. -DHR REVIEW: REVIEW OF THE DEVICE HISTORY RECORDS IDENTIFIED NO DEVIATIONS OR ANOMALIES DURING MANUFACTURING. INSPECTION PLAN: ALLOFIT CUP INSPECTION PLAN: CHARACTERISTIC NO. 79 FEATURE 2 SPIKES COMPLETELY INSERTED AND LOCKED WITH SCOPE OF TESTING: 50 OUT OF 50 (100%) VISUALLY AND 13 OUT OF 50 (26%) WITH GAGE. CHARACTERISTIC NO. 52 FEATURE SNAP DIAMETER 52.68 +0.02/-0.02 WITH SCOPE OF TESTING: 13 OUT OF 50 (26%) WITH GAGE. DURASUL INSERT INSPECTION PLAN: CHARACTERISTIC NO. 16 FEATURE SNAP DIAMETER 52.69 +0.05/-0.05 WITH SCOPE OF TESTING: 80 OUT OF 80 (100%) WITH GAGE. CONCLUSION: IT WAS REPORTED THAT AN ALLOFIT SHELL AND AN ALLOFIT ALPHA INSERT WERE IMPLANTED IN THE RIGHT HIP ON (B)(6) 2020. THE INSERT DISLOCATED, LEAVING THE PATIENT WITH AN INSTABLE HIP JOINT, BARELY ABLE TO WALK. THE PATIENT WAS REVISED ON (B)(6) 2020. THE SHELL WAS ALSO REPLACED AS A NEW ALLOFIT INSERT COULD NOT BE ANCHORED WITHIN THE SHELL DURING REVISION SURGERY. REVIEW OF THE PROVIDED X-RAYS CONFIRMED THE LATERAL SUBLUXATION OF THE FEMORAL HEAD WITHIN THE ACETABULAR SHELL INDICATING INSERT DISPLACEMENT ONE WEEK AFTER IMPLANTATION. THIS COMPLIES WITH THE DESCRIBED INTRAOPERATIVE FINDINGS FROM THE REVISION SURGERY, DESCRIBING A MEDIOCAUDALLY LUXATED INSERT WITH THE METAL HEAD STILL BEING PLACED WITHIN THE ACETABULAR SHELL. THIS IS ALSO SUPPORTED BY THE VISUAL EXAMINATION OF THE RECEIVED ALLOFIT SHELL WHICH REVEALED A WORN AND POLISHED AREA AROUND THE SCREW HOLES CLOSE TO THE RIM OF THE SHELL, INDICATING A DIRECT ARTICULATION OF THE METAL HEAD ON THE WALL OF THE ALLOFIT SHELL. FURTHER, ONE OUT OF THE TWO PINS OF THE ALLOFIT SHELL, SUPPOSED TO PREVENT ROTATION OF THE INSERT, IS MISSING. HOWEVER, IT REMAINS UNKNOWN AT WHAT POINT IN TIME THE PIN FELL OUT. THE MANUFACTURING RECORDS SHOW THAT BOTH PINS WERE PROPERLY PLACED AND LOCKED WITHIN THE ALLOFIT SHELL. THE RECEIVED INSERT HAS ONLY ONE PIN INDENTATION ON ITS OUTER SURFACE, INDICATING THAT THE PIN OF THE ALLOFIT SHELL WAS ALREADY MISSING PRIOR TO THE ATTEMPT TO ANCHOR THIS NEW INSERT. IN ADDITION, HALF OF THE POLAR PEG IS INDENTED, WHICH SUGGESTS THAT THE INSERT HAD NOT BEEN PROPERLY ALIGNED WITHIN THE ALLOFIT SHELL PRIOR TO IMPACTION. IT IS POSSIBLE THAT A PERFECT ALIGNMENT OF THE INSERT WAS PREVENTED BY DEFORMATIONS OF THE ALLOFIT SHELL THAT HAD OCCURRED DUE TO THE INSERT DISLOCATION. THE DISLOCATED INSERT, WHICH WAS IMPLANTED DURING INITIAL SURGERY, HAS NOT BEEN RETURNED, THEREFORE, A VISUAL EXAMINATION COULD NOT BE PERFORMED. INSERT DISLOCATION CAN BE CAUSED BY VARIOUS REASONS, SUCH AS INSUFFICIENT PRIMARY STABILITY OF THE INSERT DUE TO MALPOSITION WITHIN THE SHELL, INSUFFICIENT IMPACTION OF THE INSERT, REMNANTS OF SOFT TISSUE BETWEEN THE INSERT AND THE SHELL, AND DEFORMATION OF THE INSERT AND/OR THE SHELL DUE TO LOAD. THE QUALITY RECORDS SHOW THAT ALL SPECIFIED CHARACTERISTICS HAVE MET THE SPECIFICATIONS VALID AT THE TIME OF PRODUCTION. THEREFORE, THE INVESTIGATION DID NOT IDENTIFY A NONCONFORMANCE OR A COMPLAINT OUT OF BOX (COOB). DUE TO THE UNAVAILABILITY OF THE DISLOCATED INSERT AND BECAUSE THE CAUSE MAY BE MULTIFACTORIAL, THE INVESTIGATION DID NOT LEAD TO A SPECIFIC ROOT CAUSE. THE NEED FOR CORRECTIVE MEASURES IS NOT INDICATED AND ZIMMER SWITZERLAND MANUFACTURING GMBH CONSIDERS THIS CASE AS CLOSED. ZIMMER BIOMET'S REFERENCE NUMBER OF THIS FILE IS (B)(4)..

Additional Manufacturer Narrative · 0

ADDITIONAL INFORMATION WHICH WAS RECEIVED ON (B)(6) 2020. THIS FOLLOW-UP REPORT IS BEING FILLED TO RELAY ADDITIONAL INFORMATION, WHICH WAS UNKNOWN AT THE TIME OF THE PREVIOUS MEDWATCH. THE MANUFACTURER RECEIVED SURGICAL REPORT AND PER FOR REVIEW. SHOULD ADDITIONAL INFORMATION BECOME AVAILABLE AND / OR THE DEVICE(S) BE RETURNED FOR EVALUATION AND AN INVESTIGATION RESULT BE AVAILABLE, THAT CHANGES THIS ASSESSMENT, AN AMENDED MEDICAL DEVICE REPORT WILL BE SUBMITTED. ZIMMER¿S REFERENCE NUMBER OF THIS FILE IS (B)(4).

Description of Event or Problem · 0

INVESTIGATION DONE.

Description of Event or Problem · 0

PATIENT WAS IMPLANTED ON THE RIGHT SIDE AND UNDERWENT REVISION SURGERY DUE TO DISLOCATION OF INLAY AND INSTABILITY IN WALKING. THE CUP WAS REPLACED AS A NEW INLAY COULD NOT BE FIXED INTO IT. THE ENTIRE SECOND OPERATION WAS CARRIED OUT BECAUSE OF THE EVENT, AND RESULTED IN A DELAY FOR THE ENTIRE HEALING PROCESS, DURING THE REVISION OPERATION THERE WAS A FURTHER DELAY OF ABOUT 20 MINUTES BECAUSE A NEW INLAY COULD NOT BE ANCHORED AND THE ENTIRE CUP HAD TO BE CHANGED.

Additional Manufacturer Narrative · 1

CONCOMITANT MEDICAL PRODUCTS: ORIGINAL M.E. MLLER, STEM, PT-S30, STRAIGHT, LATERAL, CEMENTED, 13.75, TAPER 12/14. CATALOG#: 350039137; LOT#: 3021648. COCR HEAD, M¸ 36/0, TAPER 12/14. CATALOG #: 0101012366; LOT#: 3022367. THERAPY DATE: (B)(6) 2020. THE MANUFACTURER RECEIVED X-RAYS AND OTHER SOURCE DOCUMENTS FOR REVIEW. THE MANUFACTURER DID NOT RECEIVE THE DEVICE FOR INVESTIGATION. WHERE LOT NUMBERS WERE RECEIVED FOR THE DEVICES, THE DEVICE HISTORY RECORDS WERE REVIEWED AND FOUND TO BE CONFORMING. A CAUSE FOR THIS SPECIFIC EVENT CANNOT BE ASCERTAINED FROM THE INFORMATION PROVIDED. AS SOON AS SUPPLEMENTAL INFORMATION BECOMES AVAILABLE AN UPDATED REPORT WILL BE SUBMITTED. ZIMMER BIOMET¿S REFERENCE NUMBER OF THIS FILE IS (B)(4).

Description of Event or Problem · 1

PATIENT WAS IMPLANTED ON THE RIGHT SIDE AND UNDERWENT REVISION SURGERY DUE TO DISLOCATION OF INLAY AND INSTABILITY IN WALKING. THE CUP WAS REPLACED AS A NEW INLAY COULD NOT BE FIXED INTO IT.

Devices

Seq	Brand	Generic	Product Code	Manufacturer	Model	Lot	UDI-DI
783853	ALLOFIT-S ALLOCLASSIC, SHELL WITH POLAR SCREW PLUG, UNCEMENTED, 58/LL	ALLOFIT-S ALLOCLASSIC, SHELL WITH POLAR SCREW PLUG, UNCEMENTED	KWA	ZIMMER SWITZERLAND MANUFACTURING GMBH	N/A	3010126

Patients

Seq	Age	Sex	Outcome	Treatment
1	59 YR		Hospitalization\| R	SEE H10 NARRATIVE