MAUDE Adverse Event Report: STRYKER GMBH TIBIAL COMP,SINGLECOATED US VERSION, LARGE; PROSTHESIS, KNEE, FEMOROTIBIAL, UNICOMPARTMENTAL, SEMI-CONSTRAINED, METAL/POLYME

Catalog Number 400263

Device Problem Device Operates Differently Than Expected (2913)

Patient Problem No Code Available (3191)

Event Date 09/17/2015

Event Type  Injury  

Manufacturer Narrative

(b)(4).Once the investigation has been completed any additional information will be reported in a supplemental report.

Event Description

On (b)(6) 2015 a revision of a star ankle was performed.It was reported that " activity of patient: very active, used femoral head allograft for a cyst.The reason for revision was that the talus subsidence.Patient's bone quality is good.Revised to fusion, used arthrex fusion plate.

Manufacturer Narrative

Investigation conclusion: evaluation revealed all three implants reported to be primary products.No further associated product was reported.Review of the device history records of the reported three implants revealed no conspicuities; deficiency in material or manufacturing was not found.The affected implants were documented as faultless prior to distribution.Thus, we exclude deviations in material and manufacturing.In the case presented a (b)(6) male patient had been treated with a scandinavian total ankle replacement approximately two years before he underwent a revision surgery due to a talus subsidence.A revision to an arthrex fusion plate was carried out on 09/17/2015.Incidentally, no product failure / malfunction was reported, the issue is about a talus subsidence, which hence inevitably resulted in a removal of the reported implants and a fusion to a arthrex fusion plate, as reported.The products were shipped to the external lab exponent in september 2015.The photos provided by exponent showed all reported items with traces of use, but without significant damage.All implants were found to be in a good general condition after explantation.Implant loosening and subsidence had already been clinically assessed by a consultant hcp: "in most cases, the trabecular bone structure will be adapted to the plasma spray coated surface of the metallic components in a remodeling process correspondent to the lines of forces resulting in a stable connection between bone and the metallic components.But, in the course of time this integration of the endoprosthesis to the bone structure may fail due to any reason and result in loosening of one or both metallic components.Septic and aseptic implant loosening is the main failure mode in total arthroplasty of the ankle joint.Depending on the individual kind of failure, it is possible to revise the endoprosthesis and to exchange the affected component(s)." "subsidence caused by collapse of the tibial bone or the talar bone structures or loss of the ligament stability of the ankle joint is a rare event, but will require removal of the endoprosthesis and ankle fusion." implant subsidence is furthermore nominated in the scientific literature: "component subsidence may result from poor bone quality, osteolysis-related bone loss, or poor component positioning.Early subsidence of a millimetre or less may represent settling of the components into a stable position and does not portend failure of the implants.(2) a rsa study of 15 rheumatoid patients had shown that "tibial components tend to subside into dor flexion, valgus, and proximally by less than a millimetre during the first 3 months, and stabilize by 6 months".Since most designs do not allow axial impaction of the component, this settling may represent the implant finding a stable position as weight-bearing is allowed.Patients with severe osteoporosis or avascular necrosis may not have strong enough bone to support the placement of a total ankle replacement." "a number of factors affect risk of subsidence.Initial implant positioning may contribute to subsidence.Subsidence tends to occur in the anterior distal tibia, dorsiflexing the tibial component, or in the anterior talus or posterior talus.Anterior translation of the talar component or excessive dorsiflexion of the tibial component should be avoided to prevent overloading the bone in these at risk areas." regarding the outstanding patient data (e.G pre-existing illnesses, unreasonable stresses) it could not be determined if the patient conditions were adequate for the used implants respectively if potential adverse effects may have contributed to the talus subsidence.As no x-ray documentation and as no surgery reports / medical records were available, a medical review was not possible.It could not be determined, whether the implant had been placed according to the anatomical requirements.It could furthermore not be determined, whether the components had been implanted in the correct positions.Nevertheless, based on the medical experiences cited and to the limited information given and referring to no found deviation in the manufacturing documents as well as to the photos provided by exponent, the event was not linked to a deficiency of the devices, but was rather most likely patient related.Since the issue is about subsidence of the talus and the event was not linked to a deficiency of the devices, review / trending of the complaint history was deemed not necessary in this case.Accordingly, the occurrence threshold or risk threshold can be neglected.No non-conformity was identified.

Event Description

On (b)(6) 2015 a revision of a star ankle was performed.It was reported that " activity of patient: very active, used femoral head allograft for a cyst.The reason for revision was that the talus subsidence.Patient's bone quality is good.Revised to fusion, used arthrex fusion plate.

• Brand Name: TIBIAL COMP,SINGLECOATED US VERSION, LARGE
• Type of Device: PROSTHESIS, KNEE, FEMOROTIBIAL, UNICOMPARTMENTAL, SEMI-CONSTRAINED, METAL/POLYME
• Manufacturer (Section D): STRYKER GMBH; bohnackerweg 1; postfach; selzach 2545 ; CH 2545
• Manufacturer (Section G): STRYKER GMBH; bohnackerweg 1; postfach; selzach 2545 ; CH 2545
• Manufacturer Contact: anna jusinski ; 325 corporate drive; mahwah, NJ 07430 ; 2018315000
• MDR Report Key: 5159283
• MDR Text Key: 28596362
• Report Number: 0008031020-2015-00416
• Device Sequence Number: 1
• Product Code: NTG
• Combination Product (y/n): N
• Reporter Country Code: US
• PMA/PMN Number: P050050
• Number of Events Reported: 1
• Summary Report (Y/N): N
• Report Source: Manufacturer
• Source Type: company representative
• Reporter Occupation: Other
• Type of Report: Followup
• Report Date: 09/25/2015

1 Device was Involved in the Event

1 Patient was Involved in the Event

• Is this an Adverse Event Report?: Yes
• Is this a Product Problem Report?: Yes
• Device Operator: Lay User/Patient
• Device Expiration Date: 07/31/2018
• Device Catalogue Number: 400263
• Device Lot Number: 130409/0401
• Was Device Available for Evaluation?: Device Returned to Manufacturer
• Date Returned to Manufacturer: 09/17/2015
• Is the Reporter a Health Professional?: No
• Initial Date Manufacturer Received: Not provided
• Initial Date FDA Received: 10/19/2015
• Supplement Dates Manufacturer Received: Not provided
• Supplement Dates FDA Received: 02/26/2016
• Was Device Evaluated by Manufacturer?: No
• Date Device Manufactured: 07/31/2013
• Is the Device Single Use?: Yes
• Is This a Reprocessed and Reused Single-Use Device?: No
• Type of Device Usage: Initial
• Patient Sequence Number: 1
• Patient Outcome(s): Required Intervention
• Patient Age: 63 YR