PHOTODYNAMIC BONE STABILIZATION SYSTEM

Description of Event or Problem

AN ILLUMINOSS IMPLANT USED WITH A MINI PLATE IN A COMMINUTED HUMERUS FRACTURE FAILED IN A 77 YEAR OLD PATIENT, AND THE USER EXPERIENCED DIFFICULTY REMOVING THE ENTIRE ILLUMINOSS DURING THE REVISION SURGERY, SO IT WAS LEFT PARTIALLY BEHIND WITH A NEW LOCKING PLATE. THE PATIENT HAD AN INFECTION PRESENT DURING THE REVISION AND REQUIRED MULTIPLE TREATMENTS OF IRRIGATION AND DEBRIDEMENT AND ANTIBIOTICS WHICH DID NOT CLEAR THE INFECTION. ALL HARDWARE WAS REMOVED FROM THE PATIENT, AND A CLAM SHELL OSTEOTOMY WAS REQUIRED TO REMOVE THE DISTAL PORTION OF THE ILLUMINOSS DEVICE.

Additional Manufacturer Narrative

A MEDICAL OVERSIGHT REVIEW WAS HELD IN WHICH THE EVENT WAS REVIEWED WITH A MEDICAL REVIEWER. IT WAS NOTED THAT IN THE INDEX PROCEDURE A METACARPAL PLATE WAS USED, WHICH IS NOT ANATOMY APPROPRIATE FOR THE HUMERUS FRACTURE. WHILE THE ARTICLE DOES NOT HAVE PRE-OP OR IMMEDIATELY POST OP THE INDEX PROCEDURE, THE X-RAYS AFTER THE IMPLANT BREAK SHOW A HIGHLY COMMINUTED FRACTURE. THE MEDICAL REVIEWER OBSERVED THAT THE INDEX PROCEDURE DOES NOT APPEAR TO HAVE APPROPRIATELY STABILIZED THE FRACTURE. THE COMMINUTION GOES ALL THE WAY UP INTO THE HUMERAL HEAD, AND THE PLATE USED WAS MUCH TOO SMALL TO STABILIZE THE FRACTURE, SO THE CONSTRUCT WAS DESTINED TO FAIL. THE MEDICAL REVIEWER STATED THAT THE REVISION WITH THE LARGE PLATE APPEARED MUCH MORE STABLE AND APPROPRIATE FOR THIS FRACTURE. THE MEDICAL REVIEWER ALSO STATED THAT BASED ON THE X-RAYS IT APPEARED THAT THE ILLUMINOSS IMPLANT SHOULD HAVE BEEN ABLE TO BE PULLED OUT FROM THE FRACTURE SITE BASED ON THE FLUTED SHAPE OF THE IMPLANT AND SEVERE COMMINUTION AT THE FRACTURE SITE, HOWEVER THE SURGEONS WERE UNABLE TO REMOVE THE DISTAL PORTION OF THE IMPLANT. THE MEDICAL REVIEWER OBSERVED THAT BECAUSE THE DISTAL PORTION OF THE ILLUMINOSS WAS LEFT IN THE PATIENT, THE PATIENT WOULD BE UNLIKELY TO BE ABLE TO CLEAR THIS INFECTION WHEN A FOREIGN BODY REMAINS. IT WAS NOTED THAT THE SURGEONS DID NOT USE THE ILLUMINOSS REMOVAL OR EXTRACTION SET, AND INSTEAD USED A SCHANZ PIN TO ATTEMPT TO REMOVE THE IMPLANT. THE ARTICLE STATES THAT THE ILLUMINOSS DEVICE WAS DIFFICULT TO REMOVE DUE TO INTERDIGITATION OF THE IMPLANT WITHIN THE ENDOSTEAL CANAL AND THE PLASTIC LINING OF THE DEVICE REMAINED ADHERENT TO THE CANAL. A SMOOTH SURFACED PET IS GENERALLY NOT CONDUCIVE TO INTERDIGITATION INTO BONE. INTERDIGITATION, OR INTEGRATION OF THE MATERIAL INTO THE BONE TISSUE TYPICALLY REQUIRES A SURFACE TEXTURE WHICH ALLOWS BONE CELLS TO ATTACH, GROW, AND PROLIFERATE AROUND AND INTO THE IMPLANT. SMOOTH PET LACKS THE SURFACE ROUGHNESS OR POROSITY WHICH IS TYPICALLY CONDUCIVE TO FACILITATE INTERDIGITATION. THE STABILIZATION COMES FROM THE VARIABILITY IN THE GEOMETRY OF THE IMPLANT WITHIN THE CANAL NOT DUE TO ADHERENCE OF THE IMPLANT TO THE BONE. WHILE IT IS UNLIKELY THAT THE ILLUMINOSS IMPLANT (ENCASED BY PET) BECAME INTERDIGITATED WITH THE ENDOSTEAL CANAL, IT IS POSSIBLE THAT THE PET LINING OF THE DEVICE REMAINED IN THE CANAL WHEN THE POLYMER PORTION OF THE IMPLANT WAS REMOVED, AS DESCRIBED IN THE ARTICLE. THE PET BALLOON DOES NOT ADHERE TO THE POLYMER PORTION OF THE IMPLANT WHEN IT IS CURED, SO IT IS POSSIBLE THAT WITH AN IMPLANT BROKEN INTO MULTIPLE PIECES, WHEN THE POLYMER CENTER PORTION IS REMOVED, THE PET BALLOON MAY NOT BE FULLY REMOVED WITH THE POLYMER CENTER. WHEN INFLATED THE ILLUMINOSS IMPLANT CONFORMS TO THE SHAPE OF THE INTERMEDULLARY CANAL, WHICH COULD RESULT IN THE PET BALLOON REMAINING IN THE CANAL WHEN THE POLYMER CENTER OF THE IMPLANT IS INITIALLY REMOVED. THE STABILIZATION COMES FROM THE VARIABILITY IN THE GEOMETRY OF THE IMPLANT WITHIN THE CANAL AND IS NOT DUE TO FIXATION OF THE IMPLANT TO THE BONE. THE PET LIKELY REMAINED IN THE CANAL DUE TO THE FRICTION BETWEEN THE ROUGH SURFACE OF THE BONE BEING GREATER THAN THE FRICTION BETWEEN THE PET AND THE POLYMERIC IMPLANT. THE VARIATIONS IN THE GEOMETRY OF THE BONE COULD ALSO HAVE CAUSED TEARING OF THE PET DURING REMOVAL. IN ADDITION, THE POLYMER IMPLANT SHRINKS ABOUT 1.5% WHEN IT CURES LEAVING A SMALL AMOUNT OF SPACE BETWEEN THE POLYMER AND THE PET. IN THIS CASE THE REMAINING PET WAS ABLE TO BE REMOVED WITH RONGEURS. A POSITIVE CULTURE WAS OBTAINED DURING THE INITIAL REVISION SURGERY PERFORMED, INDICATING THAT THE INFECTION WAS LIKELY CAUSED BY THE INDEX PROCEDURE OF THE ILLUMINOSS WITH THE MINI PLATE AND SCREWS. INFECTIONS CAN BE CAUSED BY MANY FACTORS INCLUDING POOR ASEPTIC TECHNIQUE DURING THE PROCEDURE OR NONSTERILE IMPLANTS OR INSTRUMENTS. OTHER RISK FACTORS FOR SURGICAL INFECTIONS INCLUDE PATIENT HISTORY (IMMUNODEFICIENCY, CANCER, DIABETES, HISTORY OF SMOKING ETC.) AND LENGTH OF TIME OF THE SURGICAL PROCEDURE. THE MEDICAL HISTORY OF THE PATIENT IN THIS ARTICLE IS UNKNOWN. THE OCCURRENCE OF INFECTION FOR THE ILLUMINOSS DEVICE IS LESS THAN THAT DOCUMENTED IN THE LITERATURE FOR OTHER STATE OF THE ART FRACTURE FIXATION DEVICES. THE INFECTION RATE FROM THE CLINICAL EVALUATION REPORT WHICH ANALYZED BOTH THE LITERATURE, AND THE COMPANY DATA (COMPANY RUN STUDIES) HAD AN OVERALL POPULATION OF 1044 THAT REPORTED ADVERSE EVENTS WITH A TOTAL OF 14 INFECTIONS. THIS IS A RATE OF 1.3%. THIS INCLUDES SUPERFICIAL INFECTIONS. (CER-1001_A). ULTIMATELY, THE CAUSE OF THE INFECTION IS UNKNOWN, AND IT IS UNKNOWN IF THE ILLUMINOSS DEVICE CAUSED OR CONTRIBUTED TO THE INFECTION BECAUSE THERE ARE MANY OTHER POTENTIAL CAUSES OF THE INFECTION (CONTAMINATION OF THE PLATE AND SCREWS USED, CONTAMINATION OF THE INSTRUMENTS USED IN THE PROCEDURE, ASEPTIC TECHNIQUE DURING THE PROCEDURE AND PATIENT MEDICAL HISTORY). CONCLUSIONS: 1. THE CAUSE OF THE IMPLANT FAILURE IS DUE TO AN INSUFFICIENT INITIAL FIXATION IN WHICH THE ILLUMINOSS WAS USED IN A HIGHLY COMMINUTED FRACTURE WITH AN ANATOMY INAPPROPRIATE PLATE (METACARPAL PLATE USED IN THE HUMERUS). 2. THE CAUSE OF THE DIFFICULTY REMOVING THE ILLUMINOSS IMPLANT IS DUE TO THE SURGEONS NOT USING THE ILLUMINOSS REMOVAL OR EXTRACTION SET AND ASSOCIATED TECHNIQUE TO REMOVE THE IMPLANTS PER THE LABELING. 3. THE CAUSE OF THE INFECTION IS UNKNOWN. INFECTIONS CAN BE CAUSED BY MANY FACTORS INCLUDING POOR ASEPTIC TECHNIQUE DURING THE PROCEDURE OR NONSTERILE IMPLANTS OR INSTRUMENTS. OTHER RISK FACTORS FOR SURGICAL INFECTIONS INCLUDE PATIENT HISTORY (IMMUNODEFICIENCY, CANCER, DIABETES, HISTORY OF SMOKING ETC.) AND LENGTH OF TIME OF THE SURGICAL PROCEDURE. IN THIS CASE, THE ILLUMINOSS WAS USED IN CONJUNCTION WITH A MINI PLATE AND MULTIPLE SCREWS, WHICH ALSO COULD HAVE BEEN THE SOURCE OF THE INFECTION.