This follow-up report is being filled to relay investigation result.Additional and corrected information are filled in the following fields: additional: if follow-up, what type.Correction: date of report; concomitant medical products; pma/510k10.Dhr review: the device manufacturing quality records indicate that the released components met all requirements to perform as intended.Trend analysis: no trend considering the following event is identified: does not fit or function.Event description: it was reported that the durasul inlay 54 mm (ref: (b)(4), lot: 2962348) could not be anchored.The implantation was just possible with a new 54 mm inlay and removing the pole plug screw from the cup bottom.The surgeon has the impression that the depth of the slot on the pole plug screw for the admission of the inlay central pin is to small for that cup.To complete the procedure a new inlay 54 mm (locking screw was omitted) has been used.The cup remain implanted in patient.The surgeon also reported that the frequency of similar events had increased.A similar case had happened to him two weeks ago (see complaint: (b)(4).Also, other 3 similar events happened to other surgeons (see (b)(4).Review of received data: no medical data such as surgical notes or any other case-relevant documents received.Device analysis: visual examination: pole plug: the upper surface of the pole plug shows some scratches and indents.No conspicuousness could be identified on the thread or bottom surface.Durasul liner: mark of impactior could be seen on the rim.On outer surface of the rim, several severe damage marks/slits can be seen.Also, shallow indentations could be seen on several place on the outer sphere surface.These indentations are not aligned symmetrically to the center it could be an indication that the liner were not centered to the cup during insertion.Also, scratches could be seen on the outer surface.The central peg has round edge, a linear indent on the tip, shorter and wider shape, it might be compressed against the inner surface of the cup.Measurements: to ensure the pole plug has correct dimensions, relevant characteristics according to inspection plan were measured with caliper z 7568.Characteristic no.02 feature diameter 5 +0.2/0.Specification: max.5.2 mm; min.5.0 mm.Measured value: 5.03 mm.Characteristic no.08 feature dimension 3.8 +0.1/0.Specification: max.3.9 mm; min.3.8 mm.Measured value: 3.83 mm.Characteristic no.07 feature dimension 4.3 +0.1/0.Specification: max.4.4 mm; min.4.3 mm.Measured value: 4.33 mm.Conclusion: the characteristic of the pole plug is within specification.The relevant characteristics of the liner could not be measured, as the peg is slightly deformed and the rim is heavily damaged.In addition, the dimensions of the returned product could already be affected as disinfection before returning using autoclave was reported.Functional test: a fitting test between the returned pole plug and the liner was performed.The peg of the liner can be easily inserted in to the opening of the pole plug.However, the functional test between pole plug and the cup could not be performed as the cup was not explanted.Review of product documentation: the compatibility check was performed from www.Productcompatibility.Zimmer.Com and showed that the product combination was approved by zimmer biomet.Liner inspection plan: characteristic no.16 feature diameter (48.69mm +0.05/-0.05) with scope of testing: aql 1.0.Means of inspection: 3d measuring program.Characteristic no.17 feature diameter (48.63mm +0.05/-0.05) with scope of testing: aql 1.0.Means of inspection: 3d measuring program.Characteristic no.38 feature dimension (4.6mm +0.1/-0.1) with scope of testing: aql 1.0.Means of inspection: caliper.Pole plug inspection plan: characteristic no.02 feature dimension (5 +0.1/0.0) with scope of testing: aql 2.5.Means of inspection: gauge.Characteristic no.07 feature diameter (4.3 +0.1/0.0) with scope of testing: aql 0.65.Means of inspection: height gauge.Characteristic no.08 feature diameter (3.8 +0.1/0.0) with scope of testing: aql 2.5.Means of inspection: gauge.Shell inspection plan: characteristic no.52 feature diameter (48.68mm +0.02/-0.02) with scope of testing: aql 1.0.Means of inspection: 3d measuring machine.Characteristic no.53 feature diameter (48.535mm +0.015/-0.015) with scope of testing: aql 1.0.Means of inspection: 3d measuring machine.Characteristic no.40 feature thread m8x1 with scope of testing: aql 1.0.Means of inspection: plug thread gauge and scope of testing: 100%.Means of inspection: visual examination.Root cause analysis: root cause determination using sap rmw (allofit cup and pole plug): failure of shell and liner connection due to insufficient snap geometry between shell and liner not possible, as a systematic issue with design would have been detected as part of the issue evaluation assessment.Difficult alpha liner insertion due to deformation of shell due to load possible, as the condition of the shell is unknown.However, the shell remains in patient and a new liner was successfully inserted in the shell.Intraoperative complications due to excessive or lack of insertion force leading to wrong aligned pole plug possible, as the surgeon reported that the implantation was possible only when the pole plug was removed, although no conspicuous damage was identified on the returned pole plug.Root cause determination using sap rmw (durasul liner): loss of insert-shell connection, component loosening, dislocation due to insufficient insert stability due to design (snap geometry) not possible, as a systematic issue with design would have been detected as part of the issue evaluation assessment.Intraoperative complications due to inadequate handling during transport/storage possible, as no sufficient information to exclude this cause.Intraoperative complications due to wrong alignment of insert in shell possible, as the asymmetric locations of spike indentation on the liner indicates the off-centered alignment.Intraoperative complications due to wrong positioned insert in shell possible, as the asymmetric spike indentations on the liner indicates the off-centered positioning during insertion.Intraoperative complications due to excessive impaction force possible, as damage and slits was observed on the rim of the liner.Intraoperative complications due to excessive impaction force possible, as damage and slits was observed on the rim of the liner.Intraoperative complications due to lack of adequate impaction force possible, as the spike indentation is shallow.Conclusion: the pole plug and the liner were returned for investigation, the cup remained in the patient.The quality records of all products show that all specified characteristics (material, dimensions, surface, etc.) have met the specifications valid at the time of production.The measurement of the pole plug confirmed that the product met the specification.Fitting test also shows the successful fit between the returned products.Therefore, the hypothesis of incorrect depth of pole plug could not be confirmed.The observed marks of the liner show that it might have underwent several insertion attempts.The asymmetric indentation pattern and damage of the pole peg indicates possible off-centered positioning.Impaction applied on the wrongly positioned or off-centered liner could result in deformation of the pole peg and damage of the snap geometry.The liner would no longer be able to anchor.A new liner should therefore be used.As a new liner was successfully inserted int he shell, it is less likely the cup contributed to the event.However, it is possible that the pole plug was not screwed entirely into the apical hole leading to reduced total depth for liner to seat in.Other possible cause that contribute to the difficulty of liner insertion includes slightly deformed cup by the extremely hard bone condition, presence of soft tissue or debris between cup/liner and slightly decreased liner diameter due to rather cold storage environment.However, based on the given information and the results of the investigation, we were not able to identify a specific root cause for this issue.The need for corrective measures is not indicated and zimmer gmbh considers this case as closed.Zimmer biomet¿s reference number of this file is (b)(4).
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