MAUDE Adverse Event Report: STRYKER ORTHOPAEDICS-MAHWAH 11MM PRESS FIT BOWED STEM 150; PROSTHESIS, HIP, SEMI-CONSTRAINED, METAL/CERAMIC/POLYMER, CEMENTED OR NON-POROUS

Catalog Number 6495-5-211

Device Problem Break (1069)

Patient Problem Injury (2348)

Event Date 04/03/2019

Event Type  Injury  

Manufacturer Narrative

Review of the device history records indicate devices were manufactured and accepted into final stock with no relevant reported discrepancies.There have been no other similar events for the lot referenced.A supplemental report will be submitted upon completion of the investigation.

Event Description

It was reported that the patient's distal femur was revised due to the distal stem breaking at the junction of the implant and bone.Rep confirmed there was no periprosthetic fracture.Patient was revised to a larger stem.

Manufacturer Narrative

An event regarding crack/fracture involving a gmrs stem was reported.The event was confirmed through material analysis of the returned device.Method & results: product evaluation and results: visual inspection was performed as part of the material analysis report (mar), dated 04 (b)(6) 2019 which indicated: the stem was returned fractured.The part was examined with the aid of a stereo microscope at magnifications up to 50x.The fracture occurred approximately six inches from the proximal tip adjacent to the radius base of the distal collar.Biological material was adhered to the proximal stem.Marco features including beach marks are visible on the device.Macroscopic analysis of the fracture surface indicated that the fracture origin was located within the plasma spray region of stem.A material analysis has been performed.The report concluded: the stem fractured in fatigue.The fracture origin of the stem was adjacent to the radius base of the distal collar; within the plasma sprayed region.Eds showed that the stem was consistent with astm f136 alloy and the plasma spray was consistent with astm f1580 alloy - unalloyed titanium powder.Based on the given information, no identifiable material or manufacturing discrepancies were observed on the surfaces examined.-clinician review:a review of the provided medical records by a clinical consultant revealed: x-ray printouts, all undated and unlabeled, include an ap and lateral of the right distal femur and one ct cut, all consistent with an osteosarcoma of the distal right femur.Another ap and lateral of the right distal femur demonstrates a modular distal femoral replacement with three modular segments, an uncemented stem, and one cerclage cable approximately 6-centimeters proximal to the cut end of the femur and attached to the cemented hinged knee.Skin staples are in situ and the components are in nominal position.There are eight views of the right femur with remodeling of bone with fusiform cortical thickening consistent with a well-fixed stem with the previously described implants in situ and no skin staples noted.One ap and one lateral of the right distal femur demonstrating a transverse displaced fracture of the prosthetic stem at the stem/bone junction with the modular femoral replacement is noted.There is another ap and lateral of the right distal femur with an intact, thicker femoral stem in situ with the same distal femoral replacement, skin staples in situ, and the components in nominal position.There is no clinical or past medical history, no patient demographics, no operative reports, and no examination of the explanted components available.In this young, male patient, salvage surgery as an alternative to a major amputation apparently resulted in a four-year, eight-month survivorship before an inevitable fatigue fracture occurred at the base of the well-fixed stem, which cyclically loaded with a large lever arm of the distal femoral replacement attached to a constrained hinged knee.As the young patient grew, and was active, the fracture was inevitable and treated with revision to a thicker stem.Examination of the fracture surfaces of the explanted stem would confirm this mechanism and rule out factors associated with manufacturing or implant material problems.-product history review: indicated all devices were manufactured and accepted into final stock with no reported discrepancies.Complaint history review: there have been no other similar events for the lot referenced.Conclusion: based on the medical review, in this young, male patient, salvage surgery as an alternative to a major amputation apparently resulted in a four-year, eight-month survivorship before an inevitable fatigue fracture occurred at the base of the well-fixed stem, which cyclically loaded with a large lever arm of the distal femoral replacement attached to a constrained hinged knee.As the young patient grew, and was active, the fracture was inevitable and treated with revision to a thicker stem.Examination of the fracture surfaces of the explanted stem confirmed that the stem fractured in fatigue and no identifiable material or manufacturing discrepancies were observed on the surfaces examined.No further investigation is required at this time.If additional information becomes available to indicate further evaluation is warranted, this record will be reopened.

Event Description

It was reported that the patient's distal femur was revised due to the distal stem breaking at the junction of the implant and bone.Rep confirmed there was no periprosthetic fracture.Patient was revised to a larger stem.

• Brand Name: 11MM PRESS FIT BOWED STEM 150
• Type of Device: PROSTHESIS, HIP, SEMI-CONSTRAINED, METAL/CERAMIC/POLYMER, CEMENTED OR NON-POROUS
• Manufacturer (Section D): STRYKER ORTHOPAEDICS-MAHWAH; 325 corporate drive; mahwah NJ 07430
• MDR Report Key: 8570187
• MDR Text Key: 143726649
• Report Number: 0002249697-2019-01819
• Device Sequence Number: 1
• Product Code: LZO
• UDI-Device Identifier: 07613327033656
• UDI-Public: 07613327033656
• Combination Product (y/n): N
• PMA/PMN Number: K031217
• Number of Events Reported: 1
• Summary Report (Y/N): N
• Report Source: Manufacturer
• Source Type: health professional,other
• Type of Report: Initial,Followup
• Report Date: 09/17/2019

1 Device was Involved in the Event

1 Patient was Involved in the Event

• Date FDA Received: 05/01/2019
• Is this an Adverse Event Report?: Yes
• Is this a Product Problem Report?: No
• Device Operator: Health Professional
• Device Expiration Date: 03/31/2019
• Device Catalogue Number: 6495-5-211
• Device Lot Number: 130127B
• Was Device Available for Evaluation?: Device Returned to Manufacturer
• Date Returned to Manufacturer: 04/18/2019
• Date Manufacturer Received: 08/20/2019
• Is This a Reprocessed and Reused Single-Use Device?: No
• Patient Sequence Number: 1
• Patient Outcome(s): Hospitalization; Required Intervention
• Patient Age: 19 YR