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This follow-up report is being filled to relay investigation result.Additional and corrected information are filled in the following fields: 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: do not fit or function event description: it was reported that the a durasul liners could not be anchored in the shell.The shell remain in patient and a new liner was implanted.It is unclear whether the pole plug was used.This is one of the similar events happend in kmg klinikum pritzwald.Dr.Ast reported that two similar events happened within 2 weeks (cmp-0448295 and cmp-0448312) that the implant do not anchor.New liner was implanted without the shell pole plug.The surgeon has the impression that the depth of pole plug is shallow for the peg of liner to seat in.Similar events had happened to other surgeons in the same hospital: cmp-0448327, cmp-0448347(this complaint) and cmp-0448353.Review of received data: no medical data such as surgical notes or any other case-relevant documents received.Device analysis: - visual examination: only the durasul liner was returned for investigation.Marks of the setting tool can be seen on the rim, the mark is deeper on one side and lighter on the other side.A set of clamping mark was observed on one side of the rim on both inner and outer surface.Another two dents were also identified on the rim.A significant circular cut locate on the outer surface.Two indentations can also be found on outer surface.- measurements: it was reported that the products were autoclaved before returning, due to the high temperature, the dimensions can no longer reflect the state during the event or the time of production.Nevertheless, the relavent dimensions was measured.According to inspection plan, relevant characteristics were measured with caliper z 7568.Characteristic no.16 feature diameter (48.69mm +0.05/-0.05) -specification: max.48.74 mm; min.48.64 mm -measured value: 48.52/48.96 mm (on different location) characteristic no.11 feature diameter (48.37mm +0.05/-0.05) -specification: max.48.42 mm; min.48.32 mm -measured value: 48.24/48.73 mm (on different location) characteristic no.33 feature dimension (4.0mm +0.1/-0.1) -specification: max.4.1 mm; min.3.9 mm -measured value: 3.99 mm characteristic no.38 feature dimension (4.6mm +0.1/-0.1) -specification: max.4.7 mm; min.4.5 mm -measured value: 4.63 mm -comment: the liner were slightly deformed in oval shape.However, it is unclear whether it is resulted from the handling, insertion or autoclave.Review of product documentation: - the compatibility check was not performed, as the ref number of shell is unknown.- liner inspection plan sap: - 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 sap: - 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 - the size of involved shell is unknown, therefore review of corresponding inspection plan could not be performed.- surgical technique sap: position the liner over the entrance plane of the shell and rotate clockwise.The peg of the polyethylene liner must be inserted into the pole plug hole.Complete seating of the liner with a light hammer blow.If the liner can still be rotated after light impaction, this indicates mispositionning, nonconcentric, or soft tissues interference between the liner and the shell surfaces.In such situation, remove the liner, clean both surfaces and introduce the liner back into the shell, making sure it is properly centered and repeat the seating procedure.Once the liner remains steady after light hammer blows, finalize seating with final impaction.Root cause analysis: root cause determination using sap rmw (shell): - 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, a new liner was inserted into the same shell, the possibility of this cause is low.- intraoperative complications due to inadequate handling during transport/storage => possible, as no sufficient information of exclude this cause.-intraoperative complications due to excessive insertion force, leading to wrong aligned pole plug => possible, as the pole plug has not been returned; the condition is unknown.- intraoperative complications due to lack of insertion force and/or unclean mating faces are used, leading to wrong aligned pole plug => possible, as the pole plug has not been returned; the condition is unknown.- intraoperative complications due to excessive or lack of insertion force leading to wrong aligned pole plug => possible, as the pole plug has not been returned; the condition is unknown.Root cause determination using sap rmw (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 of exclude this cause.Further, the liner has slightly deformed into oval shape.- intraoperative complications due to excessive assembly force , leading to wrong aligned inlays => possible, as the marks from setting instrument is deeper on one side.- intraoperative complications due to lack of assembly force and/or unclean mating faces are used, leading to wrong aligned inlays or loss of instrument-implant connection => possible, as the marks from setting instrument is deeper on one side.- intraoperative complications due to wrong alignment of insert in shell => not possible, as no indication of wrong alignment.Further, the circular cup on the bottom also shows the cup is centered.- intraoperative complications due to wrong positioned insert in shell => not possible, as no indication of wrong position.Further, the circular cup on the bottom also shows the cup is centered.- intraoperative complications due to excessive impaction force => possible, as a circular cut from the shell spike was observed which implies excessive primary impaction force and torque.- intraoperative complications due to excessive impaction force => possible, as a circular cut from the shell spike was observed which implies excessive primary impaction force and torque.- intraoperative complications due to lack of adequate impaction force => possible, as partially fitted snap geometry is possible due to lack of impaction force, although the the circular cut shows the spikes in the shell had been inserted into the liner.Conclusion: only the liner has been returned for investigation.The shell remain in patient, but it is unclear if the pole plug was implanted.As reported, the liner had been autoclaved before returning.The dimension could be affected by the high temperature, therefore could no longer reflect the state during the event.Nevertheless, the measurement was performed and shows the liner was slightly deformed to a oval shape.It is unclear if the deformation was resulted from the insertion, handling or the autoclaving.Nevertheless, 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 visual examination showed a unusual rotational cut at the bottom of the liner.It indicates the liner was well centered, however was rotated with heavy force after inserted by the spike of the shell.The excessive force and torque applied after contacting the shell spikes could reduce the anchoring stability.The uneven indentation mark from setting instrument could imply the instrument were not assembled optimally or the deviated direction of impacting force leading to a insufficient fit.Moreover, it is also possible that the pole plug was not aligned or 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 presence of soft tissue or debris between cup/liner and slightly decreased liner diameter due to rather cold storage environment.However, it is unknown to which extent each contributors played the role in the complaint event.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)(6).
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