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Device history records (dhr): as no lot numbers was provided for this devices, the device history records could not be reviewed.The missing device information has been requested but was not available.At zimmer (b)(4) all medical devices prior release to market undergo several quality inspections as defined in our quality procedures.Our quality inspection- and deviation procedures ensure that only products fulfilling the specification are sold.These procedures are part of the overall quality management system at zimmer (b)(4) and get regularly audited by our notified body, competent authorities and internal and external auditors.Thus, for all products sold to the market can be assumed having a complete and correct dhr.Trend analysis: no trend identified.Review of event description: a wagner sl revision stem (ref: 01.00101.916 lot: 2782216) has been received.It has been reported that in a hip revision surgery the awl ("drill") 16 and the stem 16 did not fit / match together, and it was necessary to use a stem 18.This caused a surgical delay of 20 minutes.Review of received data: no medical data such as x-rays, surgical notes or any other case-relevant documents were received.Devices analysis: visual examination: the wagner sl revision stem shows few normal signs of usage further no considerable deteriorations, deformations or imperfections can be seen.The involved awl of size 16 has not been returned.To ensure the stem has correct dimensions, relevant characteristic according to the inspection plan were measured.Characteristic no.23 feature "dimension (13.4 +0.3/0)¿, specification: max.13.7 mm; min.13.4 mm, measured value: 13.60 mm.Characteristic no.25 feature "dimension (16.0 +0.2/-0.1)¿, specification: max.16.2 mm; min.15.9 mm, measured value: 16.06 mm.Characteristic no.29 feature "dimension (12.37 +0.2/-0.1)¿, specification: max.12.47 mm; min.12.27 mm, measured value: 12.37 mm.Characteristic no.28 feature "dimension (9.77 +0.3/0)¿, specification: max.10.07 mm; min.9.77 mm, measured value: 9.94 mm.Conclusion: based on the diameters as measured above, the correct size of the stem can be confirmed.Further the dhr indicates that all components met all specifications.Functional test: a functional test was not performed as the measurements indicate that the implant components met all specifications, and it was not possible to re-create the situation occurring during the surgery.Review of inspection plan for ref 01.00101.916: characteristic no.23 feature "dimension (13.4 +0.3/0)¿ with scope of testing: aql1.0 means of inspection: "3d messmaschine".Characteristic no.25 feature "dimension (16.0 +0.2/-0.1)¿ with scope of testing: aql1.0.Means of inspection: ¿3d messmaschine¿.Characteristic no.29 feature "dimension (12.37 +0.2/-0.1)¿ with scope of testing: aql1.0.Means of inspection: ¿3d messmaschine¿.Characteristic no.28 feature "dimension (9.77 +0.3/0)¿ with scope of testing: aql1.0.Means of inspection: ¿3d messmaschine¿.Review of inspection plan sap document for ref 01.00109.016: characteristic no.9 feature "diameter (ø13.66 +0.06/-0.06)¿ with scope of testing: aql1.0.Means of inspection: ¿winkellehre typ b¿ characteristic no.10 feature "diameter (ø15.75 +0.15/-0.15)¿ with scope of testing: aql1.0.Means of inspection: ¿winkellehre typ b¿ characteristic no.20 feature "diameter (ø17 +0.2/-0.2)¿ with scope of testing: aql2.5.Means of inspection: ¿2d messprojektor¿ review of surgical techniques: in surgical technique it is described: "to check the depth of implantation and exact positioning of the prosthesis, the modular trial prosthesis are used.A trial prosthesis corresponding to the prosthesis size defined in pre-operative planning is assembled in advance, with a diameter corresponding to the awl last used, and inserted into the prepared medullary cavity." functional relationship analysis: the analysis protocol and resultant fit analysis evaluate the functional relationship between the scope of wagner sl revision stems and the awl.It is stated: "the difference in cross sections of each implant wagner sl revision stem at nominal conditions and instrument awl sl revision stem at nominal conditions is 0.25mm in diameter (0.125mm in radius).Awls are effective under ream relative to implant and are smaller in diameter.The acceptance criterion of 0.2 to 0.3mm for diameter difference between implant and awl has been met." root cause analysis: root cause determination using dfmea for ref 01.00101.916: wrong combination of implant and instruments due to lms marking is not readable under or lighting, marking.Parameters are not sufficient enough.Possible: for the wagner sl revision stem it can be confirmed it is labeled with correct information and the parameters are well readable.However, as the reported awl has not been returned it is possible it's lms marking was not readable so a wrong size was chosen during surgery.Migration of stem short and long term, splitting of femur, improper initial setting of the implant due to awl design doesn't correspond to the stem design (functionality).Not possible: as the functional relationship analysis confirms the awl's design correspond to the stem design.Malfunctioning of the device due to wrong handling of device due to wrong information, not possible: as nothing indicates the stem was handled wrongly.However, the reported event indicates the surgeon missed a relevant step (use of the trial prosthesis) and this might have played a role regarding the improper initial setting of the stem size 16.Wrong combination of the components due to lms marking is not readable under or lighting, marking parameters are not sufficient enough, possible.For the wagner sl revision stem it can be confirmed it is labeled with correct information and the parameters are well readable.However, as the reported awl has not been returned it is possible it's lms marking was not readable so a wrong size was chosen during surgery.Root cause determination using dfmea for ref 01.00109.016: instrument cannot be used with the mating instrument or mating implant as intended due to failure of instrument mating condition, not possible.As the functional relationship analysis (fra) confirms the awl's design correspond to the stem design.Damaged instruments, implants, body or wrong operational step due to surgeon or staff unfamiliar with instrument usage and handling, possible.As it cannot be excluded based on the available information.Damaged instruments, implants, body or wrong operational step due to surgeon or staff unfamiliar with instrument usage and handling, possible.As it cannot be excluded based on the available information.Conclusion summary: based on the returned product and the given information, the complaint could not be confirmed.The visual examination and the measurements did not confirm that the wagner sl revision stem was "oversized/ undersized" compared to product dimensions reported in inspection plan.Also the functional relationship analysis confirms the awl's design correspond to the stem's design.As the reported awl of size 16 has not been returned it is possible it was wrongly dimensioned or it's lms marking was worn/ not readable so a wrong size was chosen during surgery.Moreover, as the reported event does not mention any trial stem it is possible the surgeon missed this relevant step during surgery.Using a trial before setting the final implant would have supported the surgeon in assessing the correct position of the final implant.So in case this step was missed, it might have played a role regarding the improper initial setting of the stem size 16.The need for corrective measures is not indicated and zimmer (b)(4) considers this case as closed.Zimmer's reference number of this file is (b)(4).
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