An event regarding fractures in the distal flutes (crack/fracture) involving a securfit stem was reported.The event was confirmed.Method & results: -product evaluation and results: visual, dimensional, functional inspection, and material analysis were not performed as the item was not returned.-medical records received and evaluation: a review of the provided medical records and x-rays by a clinical consultant indicated: ¿the primary harm involved is mechanical failure of tha hip stems 10 years post implantation.No clinical outcome information is available other than that no corrective action was undertaken as a result of these failures.A single ap xray demonstrates that despite the fractures of the flutes noted both stems appear to be now well fixed ¿ albeit with the right stem in a subsided suboptimal position.¿ ¿the mechanical failures of these two stems appears to have been caused by under sizing of the implants at the time of implantation.In reviewing the x-ray both femurs demonstrate localized stem fixation and bony hypertrophy at the transitional region of the implant where the coated proximal body and the distal stem come together.This finding is consistent with of a lack of proximal loading or distal fixation of the implant.The most likely cause for this would be under sizing of the implant at the time of implantation.Under sizing would prevent initial primary mechanical fixation and support for the stem as well as abnormal stress distribution, repetitive micro motion and ultimately to fatigue fracture of the fluted distal stem.¿ -product history review: review of the device history records indicates devices were manufactured and accepted into final stock with no reported discrepancies.-complaint history review: there have been no other events for this lot.Conclusions: the reported event of fractures in the distal flutes of the implanted securfit plus max stems was confirmed.The clinician¿s review stated, ¿a single ap x-ray demonstrates that despite the fractures of the flutes noted both stems appear to be now well fixed ¿ albeit with the right stem in a subsided suboptimal position.¿ as noted in the clinicians review, the alleged root cause may have been caused by the under sizing of the implants at the time of implantation.No further investigation for this event is possible at this time as no devices and insufficient information was received by stryker orthopaedics.If devices and / or additional information become available to indicate further evaluation is warranted, this record will be reopened.
|