The reason for this revision surgery was reported as excessive wear.The previous surgery and the surgery detailed in this event occurred 2 years and 2 months apart.The healthcare professional indicated there was no delay in surgery and another suitable device was available for use.The revision surgery was completed as intended.The devices were returned to manufacturer and examined by registered medical assistant (rma) at djo surgical.A review of the device history record (dhr) shows that the poly insert met design and manufacturing requirements when released for use.There were no non-conforming material reports (ncmr) associated with the production of this lot that may have contributed to the reported event.The device was verified to have gone through an acceptable sterilization process and was within its expiration date at the time of implantation.The vendor's certificate of conformance was reviewed, and it confirms that the poly insert's material met specifications by conforming to astm f-468, gur 1050.No complaints have been filed against any other parts from this lot.Djo is aware of 16 other revisions surgeries due to worn poly inserts in the history of the epik system.There is no indication that there are any present trends or on-going issues that need review.A review of survivorship for epik knees, including a study of all wear-related complaints, has been conducted.It shows that djo's epik systems have a rate of survivorship (97.7%) that is higher than the industry standard, emphasizing that there is no larger manufacturing or design problem with epik parts.This analysis is attached to this complaint.The root cause of this complaint was a revision surgery due to excessive wear.There are several factors that may have contributed to the need to revise this epik system.The poly insert shows evidence of delamination, which is the product of oxidation, a factor known to accelerate wear.Additionally, point loading is common in unicondylar knee systems, meaning more load is focused in a single location of the poly insert.Furthermore, the location of this insert's wear is evidence of an off-center loading point, which is likely an indicator of surgical malalignment between the femur and the baseplate, which can also accelerate wear.Other patient contraindications that could have contributed to poly wear include obesity, abnormal gait, and degenerative bone disease.There are no indications of a product or process issue affecting implant safety or effectiveness.Rma examination: the femur has returned with significant bone/cement still attached, indicating good fixation to the bone.The articulating surface has several minor scuffs, signs of usual wear.The baseplate and poly insert have returned for examination, still stuck together.The baseplate has significant bone/cement still attached, indicating good fixation to the bone.The baseplate is otherwise undamaged, except a few marks around the rim which may have been from explantation.The poly insert has some delamination and some wear on the articulating surface.The insert's wear is off-center and the worn surface is smooth/shiny and pitted.
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