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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: revitan, proximal part, cylindrical, uncemented, 55, taper 12/14; catalog#: 01.00402.055; lot#: 2878752.Biolox head hip impl win gen; catalog#: unknown; lot#: unknown.Therapy date: (b)(6) 2021.Additional information which was received on apr 28, 2021.This follow-up report is being filled to relay additional information, which was unknown at the time of the previous medwatch.The manufacturer received x-rays, other source documents (surgical reports) 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.D10, concomitant medical products: revitan, proximal part, cylindrical, uncemented, 55, taper 12/14; catalog#: 01.00402.055; lot#: 2878752 biolox head hip impl win gen; catalog#: 00877503604; lot#: 2903512 cerclage cable with crimp 1.8 mm diameter cable 36 inch (910 mm) length, catalog#: 00223200228; lot#: 63722686.Review of event description: it was reported that the revitan stem was revised due to a fracture of the connection pin on (b)(6) 2021.Review of received data: x-rays: various x-rays and radiological reports concerning the thorax, the right hip and the right knee are at hand.The evaluation of the x-rays concerning the right hip and the summary of the radiological reports are summarized below.The x-rays showing the situation after the revision of the revitan stem on (b)(6) 2021, the knee x-rays and the ct scan of (b)(6) 2021 are not evaluated.Concerning the x-rays of the right hip, there are differences in the positioning of the patient resulting in slight different radiographic projections.Thus, potential changes of the bone situation around the hip prosthesis as well as the position of the prosthesis components are not always clearly recognizable.X-rays (b)(6) 2017: situation after the implantation of a primary prosthesis in the right hip.Radiological report of the x-rays taken on (b)(6) 2017: normal position of the prosthesis.No evidence of a periprosthetic fracture.No signs of metal breakage.No signs of loosening.X-rays (b)(6) 2017: compared to the previous study date, there is a periprosthetic fracture of the right femur and the stem is subsided.Radiological report of x-rays taken on (b)(6) 2017: compared to the previous study date and with the ct scan of (b)(6) 2017 there is a known periprosthetic fracture after implantation of the right hip prosthesis and former hip prosthesis on the left side with a leg length difference of approximately 13 mm.X-rays (b)(6) 2017: a revitan stem is implanted in the right hip with two cerclage wires around the femur in the diaphysis.Medially, there is no bone visible in the proximal anchoring region of the proximal part of the revitan stem.All three views show an inhomogeneous bone structure between the medial cortical bone and the distal region of the proximal stem part and the proximal region of the distal stem part.Radiological report of x-rays taken on (b)(6) 2017: normal position of the artificial joint surfaces.No periprosthetic femur fracture.Inconspicuous postoperative image.X-rays (b)(6) 2021: the pelvis overview and the ap view have a different projection compared to the previous study date.They show that the proximal part of the revitan stem is slightly tipped medially.The tilting of the proximal stem part exposes laterally a radiolucent gap that is bordered by a sclerotic line on the bone side.In addition, along the medial side of the distal region of the proximal stem part there is a radiolucent gap recognizable that is bordered by a sclerotic line on the bone side.In the second views radiolucent gaps bordered by a sclerotic line on the bone side can be seen along the anteromedial and posterolateral side of the proximal stem part.Radiological report of x-rays taken on (b)(6) 2021: comparison with the previous examination of (b)(6) 2017: slightly different projection of the thp on the right side.No evidence of radiolucent lines.No material fracture and no dislocation of the prosthesis.No evidence of a prosthesis loosening.X-rays (b)(6) 2021: no obvious changes compared to the previous study date.X-rays (b)(6) 2021: situation after the revision of the revitan stem.Surgical report of (b)(6) 2017: pre-operative diagnosis: right coxarthrosis.Operation: implantation of a cementless total hip prosthesis (thp) in the right hip.Stem: merotan, size 15, cementless, merete.Cup: epicup, size 56/36 mm, xpe inlay, merete.Head: bio ball, 36 mm, merete.Surgical report of (b)(6) 2017: diagnosis: periprosthetic femur fracture with loosening of the stem, right hip procedure: the hip joint is opened through the old skin incision.The head is dislocated and the loosened stem is removed.The medullary canal is scraped, debrided and irrigated extensively.The femur fracture is reduced, held in place using forceps and two cerclage cables for a safe anatomical reduction.This is achieved without any problems under fluoroscopy.There is a correct reduction.The femur is reamed distally until size 20 using the appropriate profilers.Different lengths are tried out.Overall, the 20/200 distal stem and a proximal part size 55 show a very good result.The definitive stem is assembled and inserted.It fits excellently in both planes.Subsequent reduction with different heads is made.With size 36xl there is a stable situation.There is no tendency of dislocation.The fluoroscopy check shows a correct position and a correct reduction.There is a correct leg length and a correct offset.Implant card, (b)(6) 2017: apart from the implants listed on the first page of this report, according to the affixed product stickers, two cerclage cables with crimp were also implanted.Revision report of (b)(6) 2021: diagnosis: fracture of the connection pin of the revitan stem, right hip procedure: the hip joint is opened through the old skin incision.After the acetabulum is freed and the head is exposed, the dislocation of the prosthesis is performed.Subsequently, the proximal part of the revitan stem can be removed.The connection pin fracture is visible.Around the proximal part the typical tissue is visible, without any evidence of an infection.Debridement, microbiological and histopathological examination is made.Using fluoroscopy a bone osteotomy is marked and performed.The distal stem part is exposed with the chisel and then knocked out cranially via a hole in the stem.The further steps describe the preparation of the femur and implantation of a wagner prosthesis and a biolox delta head.Zimmer biomet product experience report (zper): the event description section mentions that post-operatively there was a normal course.Suddenly the patient had pain in the hip on (b)(6) 2021.The given height and weight of the patient results in a bmi of 29.5 which can be classified as overweight according to the bmi scale (bmi 25.0 ¿ 29.9) [1].Product evaluation: visual examination: the connection pin of the revitan stem is fractured in the non-blasted area.The fracture is located approximately 0 to 3 mm below the proximal end of the distal part.The proximal part of the connection pin is still assembled to the proximal part of the revitan stem.On the lateral side of both the proximal and distal fracture surface several ratchet marks can be observed pointing to several fracture origins.The proximal fracture surface exhibits a main large fracture level and an adjacent smaller fracture level.The distal fracture surface exhibits only one fracture level and therefore, it is assumed that smaller fragments from the proximal fracture surface are missing.On both fracture surfaces polished areas can be recognized medially.Some scratches can be seen on the middle region of the distal fracture surface.Macroscopically, as far as visible, no deficiencies that could have triggered or favored the fracture were found on the fracture surfaces.There is a wear mark on the lateral face surface of the distal stem body.Some scratches and nicks can be observed on the medial face surface of the stem body and inside of the posterior shoulder, respectively, most probably deriving from revision surgery.On the proximal part of the revitan stem, revision damage in the form of scratches and instrument marks can be seen in the neck and shoulder regions as well as on the proximal half of the medial and anterior region of the anchoring surface.Slightly polished areas can be seen on the anchoring surface on the posterolateral side.The distal end of the lateral side shows as well a slightly polished spot.There are no signs of bone ongrowth on the anchoring surface of the proximal stem part.On the proximal fracture part of the connection pin there is an approximately half circumferential stripe with some surface changes adjacent to the fracture surface.Closer inspection of the stripe with a low power microscope (leica mz16 a) revealed smeared material and signs of fretting.On the medial and anterior sides of the stripe the edge of the fracture surface is slightly deformed outwards.Adjacent to the stripe joins the original surface followed by the blasted area.Revision damage in the form of coarse scratches and instrument marks are visible on the anchoring surface of the distal part of the revitan stem.Bone attachments are visible on the entire anchoring surface.The biolox delta head is still mounted on the proximal stem part and shows metallic smearing on the bottom bevel and the articulation surface.Review of product documentation: device purpose: all involved devices are intended for treatment.Product compatibility: select product compatibility.Dhr review: review of the device history records identified no deviations or anomalies during manufacturing.Conclusion: on (b)(6) 2017 the patient received a primary thp in the right hip (merotan stem, epicup cup, xpe inlay and bioball head from merete).On (b)(6) 2017 a revision was performed due to a periprosthetic femur fracture and loosening of the prosthesis.Only head and stem were revised using zimmer biomet products (revitan stem and biolox delta head) while the epicup cup and xpe inlay from merete remained in situ.This combination is not approved by zimmer biomet and has to be considered off-label use.The revitan revision stem system package insert that accompanied the proximal part of the revitan stem describes this under the description section: all revitan revision stems have to be used in combination with tha systems approved by zimmer gmbh (see compatibility information on www.Productcompatibility.Zimmer.Com).[2].The revitan stem was revised due to a fracture of the connection pin on (b)(6) 2021.Based on the investigation the reported event can be confirmed.The fracture occurred due to fatigue in the non-blasted area of the connection pin, few millimeters below the proximal end of the distal stem part.The appearance of the fracture surfaces points to several fracture origins located on the lateral side of the stem.The proximal fracture surface exhibits a main large fracture level and an adjacent smaller fracture level whereas the distal fracture surface exhibits only one fracture level.Therefore, it is assumed that smaller fragments from the proximal fracture surface are missing.Macroscopically, as far as visible, no deficiencies that could have triggered or favored the fracture could be found on the fracture surfaces.On the proximal fracture part of the pin there is an approximately half circumferential stripe revealing some surface changes.It is unknown if the stripe existed already before the start of the fracture or developed exclusively as a concomitant phenomenon.Bone attachments could be observed on the distal part of the revitan stem but not on the proximal part.Further, slightly polished areas can be seen on the anchoring surface of the proximal part which indicates movement between the part and the bone.It is unknown if these existed already before the start of the fracture and are associated with it or developed exclusively as a concomitant.On the x-rays taken immediately after implantation of the revitan stem it can be observed that medially, there is no bone visible in the proximal anchoring region of the proximal part of the revitan stem.In addition, an inhomogeneous bone structure can be seen between the medial cortical bone and the distal region of the proximal stem part and the proximal region of the distal stem part.The next available x-rays dated (b)(6) 2021 show that the proximal part of the revitan stem is slightly tipped medially which exposes laterally a radiolucent gap that is bordered by a sclerotic line on the bone side.In addition, along the medial, anteromedial and posterolateral sides of the distal half of the proximal stem part radiolucent gaps can be recognized that are bordered by a sclerotic line on the bone side.Based on the above described findings, the proximal bone support of the revitan stem immediately after implantation and possibly throughout the entire time in vivo can be interpreted as suboptimal.Thus, it can be hypothesized that the suboptimal proximal bone support, especially on the medial side, in combination with other factors, e.G.The surface changes observed on the connection pin and the patient¿s overweight, may have caused the fracture.It is unknown to which extent each factor had an influence on the sequence of events and if there were other influencing factors.A field safety notice was issued on (b)(6) 2017 to inform surgeons and health care professionals on the use of the revitan revision system [3].The field safety notice jointly provided the latest version of the surgical technique which indicates that: the revitan hip system is not designed for use in a fully unsupported proximal femur.Bone stock of adequate quality must be present and appraised at the time of surgery.For patients with severe proximal deficiency, a surgeon should consider surgical options to ensure proximal bone support (such as medial and/or lateral strut grafts) or switching to a monoblock revision stem.[4].In addition, the revitan® revision stem system package insert that accompanied the proximal part of the revitan stem points to these facts under the warnings section: heavy patients who engage in high levels of physical activity and who do not have proximal bone support, especially medially, are subject to a risk of implant failure when a modular revision stem is used.In such cases the surgeon should consider surgical options to ensure proximal bone support or switching to a monobloc revision stem.[2].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).In conclusion, as the cause may be multifactorial an exact root cause could not be identified for the reported event.References: [1] wikipedia body-mass-index accessed on 25 nov 2021, https://en.Wikipedia.Org/wiki/body_mass_index [2] revitan revision stem system, art.No.D011 500 286 ¿ ed.05/14 [3] field safety notice for the revitan revision system, fa 2017-01 (zfa 2016-164) [4] revitan curved revision hip system surgical technique, 06.01169.012 - rev.2 2016-11 a4 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).
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