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A technical investigation was not possible to perform, as the devices were not at hand for investigation.No trend identified.The product combination was approved by zimmer.Possible causes for the reported event according to dfmea: increased wear due to clearance too small, rim loading; increased wear due to clearance too large; no self-polishing (run-in phase) leads to increased wear due to inadequate articulation material; increased level of ions due to chemical/crevice/corrosion; increased number of wear particles due to chemical corrosion; reduced rom, increased wear due to component malpositioning; increased wear due to component mismatch (wrong size), increased wear due to component damaged during operation - scratches on articulation surface; increased wear due to wrong pairing due to missing "metasul" sticker.Based on the given information and the results of the investigation, the complaint could not be confirmed as the alleged failure could not be identified or reproduced.The need for corrective measures is not indicated and (b)(4) considers this case as closed.Zimmer's reference number of this file in (b)(4).
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Trend analysis: no trend considering the following event is identified: revision due to pain, high ion levels, disability.Device history records (dhr): the device manufacturing quality records indicate that the released components met all requirements to perform as intended.Event summary: the mmc cup was revised after approximately 4 years and 3 months in vivo.The indication for the revision surgery was given through due to pain, increased disability and pseudocyst.The per reported that a subsequent metal ion test showed positive results for cobalt serum.However, the cobalt level could not be verified against a reference because the value was not reported.Review of received data surgery notes of implantation surgery and product stickers, dated 3 june 2010 the surgical note of the implantation surgery was reviewed and the relevant points can be summarized as follows: indications: patient had ongoing problems with pain and disability.Technique: standard posterolateral approach to open the hip joint.Dissection was carried down to the fascia using cautery.Standard posterior capsulotomy was performed.Leg lengths and offset were measured.Standard femoral neck osteotomy was made.Severe femoral and acetabular arthrosis was found.Joint fluid was clear and bone quality was good.Acetabulum is reamed in 2 mm increments until cancellous bleeding bone.Acetabular component size 56 was impacted and had excellent press fit.Femur is broached up to size 56.Hip reduction with trail head and neck and taken shows excellent range of motion and stability.Ml taper stem size 9 is impacted and had excellent press fit.Head size 48 is impacted.Hip was reduced and showed again excellent range of motion and stability.Closure of the hip.The ref.No.And lot no.On the product stickers match with the marking on the received components.For the stem following information is available: m/l taper with kinectiv technology, size 9 (ref.No.: 00-7713-009-00 / lot no.: 61409701).Surgery notes of revision surgery and product stickers, dated 9 september 2014 the surgical note of the revision surgery was reviewed and the relevant points can be summarized as follows: assistant: the patient was morbidly obese.Indications: patient had previously undergone a right total hip replacement.Laboratory studies revealed mild elevation of inflammatory markers.Mri is consistent with a small pseudocyst.Continued pain and increased disability, declining quality of life despite conservative care.Technique: previous incision is used.Dissection was carried down to the fascia standard posterior capsulotomy was perform.Joint fluid was clear and no sign of any infection.Small pseudocyst in the region of the posterior aspect of the hip.Pseudocyst is debrided and copiously irrigated.Dislocation of the hip, removal of the head and the neck.Stem itself is well fixed.Acetabular component was not frankly loose but was removed without difficulty.New implants are implanted.The product stickers show the following components: continuum shell, cluster, 58 ll (ref.No.: 00-8757-058-01/ lot no.: 61817933).Longevity highly crosslinked liner, neutral, 58 ll x 36 (ref.No.: 00-8751-013-36 / lot no.: 61494556).Biolox delta ceramic femoral head, 36/m, 12/14 (ref.No.: 00-8775-036-02 / lot no.: 2606704).Bone screw, self-tapping, ø6.5 mm, 20 mm length (ref.No.: 6250-65-30 / lot no.: 61801637).Devices analysis: the mmc cup shows damage most likely from the revision surgery, e.G.Coarse scratches on the articulation surface and damage of the coating.On the anchoring side approximately 20% of the coating shows remains of bone attachments.There is one area close to the equator where the titanium vacuum plasma spray coating is chipped off.This probably occurred during revision surgery.On the articulation surface numerous fine and some coarser scratches are recognizable.The articulation surface of the metasul ldh head shows several fine scratches.There are some isolated nicks and scratches probably deriving during or after removal.Some possibly organic deposit can be observed that appears like a rainbow colored film.The head adapter and the metasul ldh head are still assembled.The structure of the stem taper seems to be imprinted on the inner surface of the head adapter.The kinectiv modular neck shows surface changes in form of corrosion on the taper connection to the stem.Other than that the kinectiv modular neck is inconspicuous.Review of product documentation: the compatibility check was performed and showed that the product combination was approved by zimmer biomet.Root cause analysis: possible causes for the reported event according to dfmea: line 1: increased wear -> due to clearance too small ¿ rim loading.Line 2: increased wear - due to clearance too large.Line 6: no self-polishing ¿ (run-in phase) leads to increased wear - due to inadequate articulation material.D) line 7: increased wear - due to perpetual boundary lubrication of articulation due to inproper design parameters (e.G.Diameter, roughness, etc.).Line 11: increased level of ions - due to chemical/crevice/ corrosion.Line 12: increased number of wear particles - due to chemical corrosion.Line 16: reduced rom, increased wear -> due to component malpositioning.Line 17: reduced rom, increased wear - due to component malpositioning.Line 18: increased wear - due to component missmatch (wrong size).Line 19: increased wear - due to component damaged during operation - scratches on articulation surface.Line 20: increased wear - due to wrong pairing due to missing metasul sticker.Line 32: increased wear - due to component damaged during operation - scratches on articulation surface.Comparison to investigation results whether it is possible and justification: line 1: not possible -product investigation did not confirm any product issue.In addition, a systematic issue with design and/or material properties would have been detected as part of the issue evaluation assessment.Line 2: not possible - product investigation did not confirm any product issue.In addition, a systematic issue with design and/or material properties would have been detected as part of the issue evaluation assessment.Line 6: not possible - the product investigation did not reveal any issue related to the articulation surface.In addition, a systematic issue with design and/or material properties would have been detected as part of the issue evaluation assessment.Line 7: not possible - the roughness is 100% inspected.In addition, a systematic issue with design and/or material properties would have been detected as part of the issue evaluation assessment.Line 11: possible - the conducted product investigation shows signs of corrosion at the taper connection.Line 12: possible - the conducted product investigation shows signs of corrosion at the taper connection.Line 16: possible - no x-ray was received.Line 17: possible - no x-ray was received.Line 18: not possible - the product combination was compatible, correct sizes were used line 19: possible - even though the received implantation surgery report does not indicate any improper handling during implantation, the correct handling of components during surgery is out of zimmer control.Therefore, proper handling during implantation cannot be confirmed.K) line 20: not possible - the product combination was compatible.L) line 32: possible - even though the received implantation surgery report does not.Indicate any improper handling during implantation, the correct handling of components during surgery is out of zimmer control.Therefore, proper handling during implantation cannot be confirmed.Conclusion summary: the mmc cup was revised after approximately 4 years and 3 months in vivo.The indication for the revision surgery was given through due to pain, increased disability and pseudocyst.The per reported that a subsequent metal ion test showed positive results for cobalt serum.However, the cobalt level could not be verified against a reference because the value was not reported.The mmc cup shows remains of bone attachments on the anchoring surface.Both articulation surfaces do not show conspicuous features.The kinectiv modular neck shows surface changes in form of corrosion on the taper connection to the stem.It is unknown if and to which extent the observed corrosion contributed to the reasons for revision and whether there were other influencing factors.Based on the above described findings and the information received it remains unknown why it came to the reported reasons for revision mentioned above.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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