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This product is manufactured by zimmer biomet winterthur and is not cleared or distributed in the u.S.However, this report is being submitted as zimmer biomet winterthur manufactures a similar device that is cleared or distributed in the united states.D10: medical products: durasul, alpha insert, ll32; catalog#: 01.00013.412; lot#: 2627792.Weber stem cemented hip impl win; catalog#: unknown; lot#: unknown.Metasul, head, xl, 32/+8, taper 12/14; catalog#: 193208; lot#: 2574055.Therapy date: (b)(6) 2021.This follow-up report is being filled to relay additional information, which was unknown at the time of the previous medwatch.Additional information was received on jun 10, 2021 and jun 23, 2021.The manufacturer received other source documents 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).
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Investigation results were made available.Event description: it was reported that patient underwent a revision surgery due to pain, partial rupture of the hip abductors and clear wear granulomas with joint effusion.Review of received data: due diligence: no further due diligence required as all required information to support the conclusion is available or was already requested.Revision report of 27, april 2021: diagnosis: wear granulomas with increased joint effusion, osteolysis around the cup and insufficiency of the hip abductors due to a partial rupture of the gluteal tendon plate in the left hip.State after implantation of a total hip prosthesis (allofit shell, durasul insert, weber cl stem, metasul head) on the left side in 2012.Indication: the patient suffers from diffuse left-sided hip pain, which is load-dependent but also partly present at rest.There is a partial rupture of the hip abductors on the one hand and on the other hand clear wear granulomas with joint effusion.The indication for the cup revision and also for revision of the hip abductors is given.Procedure: the capsule is open.Already now there are clear wear granulomas and effusion in the joint.The hip abductors are released, the hip prosthesis is dislocated and the head is removed.A gradual careful circumferential debridement including the clear scarring, especially in the anterior region, is done and all is removed.The explant instrument is inserted at 12:00 position and it is cut around the cup without significant bone loss.Overall, the cup is still well fixed, especially in the posterior region.There are clear wear granulomas in the acetabular fossa as well as in the anterior region, as evident in the mri.The anterior wall is present, but somewhat thin.The wear granulomas are scraped and delivered for bacteriology and histology.After final debridement and irrigation, the acetabulum is prepared to implant a fitmore cup, a durasul insert and a biolox delta head.A small partial rupture can then be palpated on the anterior part of the trochanter major.The anterolateral gluteal tendon plate is fixed watertight with 3 well holding transosseous fiberwire as well as with a ethibond suture and finally adapted with a pds 1-0.Swissmedic report: apart from the information already stated above in the diagnosis, the event description of the swissmedic report states that the total hip prosthesis was implanted on (b)(6)2012 by dr.(b)(6).Email from the surgeon: the email mentions the height and weight of the patient, as indicated on the first page of this report.Note of the author: the given height and weight of the patient results in a bmi of 27 which can be classified as overweight according to the bmi scale (bmi 25.0 ¿ 29.9).X-rays: there are x-rays at hand (pelvis overview and second view) taken on (b)(6) 2020, (b)(6) 2021 and (b)(6) 2021.Concerning the pelvis overviews, there is nothing conspicuous to report about the cup and the acetabular bone.All three pelvis overviews show a radiolucent line between the bone cement and the bone, laterally along the proximal region of the stem.The second views have a high brightness/contrast around the cup and can therefore not be evaluated.On all x-rays it can be observed that there is no eccentricity of the femoral head within the polyethylene insert.On the mri scan taken on (b)(6) 2020 fluid- or fluid equivalent-filled formations can be observed in the anterior region of the cup and in the acetabular fossa.Product evaluation: visual examination: there are hardly any bone attachments visible on the anchoring side of the allofit shell.The teeth of the shell¿s macrostructure are damaged, almost all around the shell¿s circumference.On the inner side of the shell the area around the polar screw is polished.On the anchoring side of the durasul alpha insert the indentations from the shell¿s fixation spikes are only faintly visible.Except for some backside changes the anchoring side of the insert shows still machining marks.The pole pin is intact.On the articulation side of the insert there is some damage on the rim.On the rim the markings are barely visible.Investigation of the articulation surface under the low power microscope revealed a central loaded area and an unloaded area around it.Further investigation of these areas under the microscope, at 100- times magnification in bright field (bf), showed that the machining marks are still visible in the unloaded zone while they are no longer visible in the loaded zone.On the metasul head several spots, most probably deriving from the use of an electrosurgical instrument during revision surgery can be recognized on one side of the articulation surface and on the bottom bevel.On the head taper signs of fretting corrosion could be found.Wear measurement: the wear measurement was carried out on a 3d measuring machine type cmm5, sip geneva.The wear map does not show a clear wear zone and therefore a determination of the wear value is not possible.However, the diameter calculated out of all measuring points is still within the manufacturing tolerances.Review of product documentation: device purpose: all involved devices are intended for treatment.Product compatibility: the product combination was not approved by zimmer biomet.Dhr review: review of the device history records identified no deviations or anomalies during manufacturing.Conclusion: according to the indication in the revision report, an allofit shell, a durasul alpha insert and a metasul head were revised due to pain, partial rupture of the hip abductors and clear wear granulomas with joint effusion after 9 years in vivo.The diagnostic section of the revision report mentions also osteolysis around the cup.However, the procedure section of the revision report states nothing about osteolysis.Further, it is described that overall, the cup is still well fixed, especially in the posterior region and an explant instrument is used to cut around the cup.Clear wear granulomas were found in the acetabular fossa and in the anterior region and samples were taken for bacteriology and histology testing.However, the results are not at hand and therefore further conclusions about these cannot be drawn.The mri scan at hand shows the presence of fluid- or fluid equivalent-filled formations in the anterior region of the cup and in the acetabular fossa.Visual examination of the allofit shell shows that there are hardly any bone attachments on the anchoring surface and damage, most probably from the explant instrument is visible almost all around the circumference.The barely visible markings on the rim of the durasul alpha insert and the faintly visible indentations from the shell¿s fixation spikes could point to the fact that the component was subject to thermal disinfection.Therefore, it could be assumed that the component is not anymore in the same condition as after its revision.A wear measurement was performed but did not show a clear wear zone.However, the diameter calculated out of all measuring points is still within the manufacturing tolerances.On the articulation surface nothing could be observed that could indicate signs of abnormal wear.On the metasul head taper signs of fretting corrosion could be found.The conditions of mounting of the head on the stem taper, e.G.Impaction force, impaction angle, condition of the taper surfaces (dry, wet), are factors that influence the quality of the taper connection.Based on the received clinical information and the examination of the revised components it can only be assumed that the phenomena observed on the head taper could have possibly led to the wear granulomas and the increased joint effusion.Peer reviewed studies have shown that, the release of corrosion products from the opening of modular junctions into the surrounding periprosthetic tissue can result in particle-induced granulomas, leading to osteolysis and aseptic loosening.Based on the investigation the reported event can be confirmed.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).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 switzerland manufacturing gmbh considers this case as closed.Zimmer biomet's reference number of this file is (b)(4).The following reports are associated with this event: 0009613350-2021-00211-2, 0009613350-2021-00209-2, 0009613350-2021-00212-2.
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