MAUDE Adverse Event Report: ENCORE MEDICAL L.P. UNIPOLAR HIP; SLEEVE, UNIPOLAR, OFFSET -3.5

Model Number	411-00-035
Health Effect - Clinical Code	No Known Impact Or Consequence To Patient (2692)
Date of Event	01/11/2019
Type of Reportable Event	Serious Injury
Additional Manufacturer Narrative
The reason for this revision surgery was reported as revision of acetabular components.The previous surgery and the surgery detailed in this event occurred 11.4 years 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 records (dhr) shows that the head, liner and shell used in the previous surgery met design and manufacturing requirements when released for use.The sleeve had two units with nonconformances that were not identified at the time of manufacture.Unit 45 of 50 taper diameter measured 0.5013 in.Where the specification was dia.0.500+/- 0.0012.An oversized condition of 0.0001 for this feature would cause the stem to taper lock with less engagement and did not contribute this failure mode.Unit 49 of 50 outer taper angle measure 5.7255 degrees where the specification was 5.7083 +0/-0.125 deg.This outer taper mates with the head which was achieved successfully.There were no non-conforming material reports (ncmr) associated with the products that may have contributed to the reported event.The devices were verified to have gone through an acceptable sterilization process and were within their expiration dates at the time of the previous surgery.Customer complaint history of the reported devices showed no present trends or on-going issues that are needing a review.There was no information submitted with this complaint about any patient activities, accidents or medical contraindications that may have contributed to the reported event.Rma examination results: the shell has been returned with scratches and gouges on the inner diameter and around the threaded hole.These marks are consistent with the process of implantation and explantation.Residual bone and tissue on the porous coating indicate that the implant achieved adequate fixation.The metal liner exhibits burnishing and wear consistent with a decade of implantation.The metal liner remains well fixed within the poly component.There is some additional damage on one side of the outside rim of the poly component which appears to be from the surgical explantation.The femoral head has been returned with minor wear on the polished exterior surface.The sleeve is well-fixed inside.The sleeve has been returned, still in taper lock with the femoral head.Its exterior has not been assessed because the sleeve cannot be separated from the femoral head, even with the use of the available head distractor tool.The head was sectioned for examination of the interior features.There is clearance between the head and sleeve, indicating an appropriate mating relationship between the components.The interior surface of the sleeve near the bottom has worn away over time into a shape that matches the proximal tip of the femoral stem.The femoral stem has substantial retained bone and tissue on the porous coated surface, as well as bone in the distal slot, indicating good fixation was achieved.Some sections of the porous coating are missing and appear to have been scraped away by a surgical instrument during the removal process.The stem has significant wear on the proximal end.The cerasiv grooves have worn away from about half of the taper surface.In the cross-section of the distal-proximal plane, the trunion measures 0.46 in., 0.04 below the nominal diameter of 0.50.The trunion has worn into a shape that matches the interior of the sleeve.The stem and the sleeve are both made of titanium (ti-6al-4v per astm f-136).The wear pattern indicates that the head was dissociated from the stem resulting in ongoing movement for an extended period of time.Additionally, the neck of the stem has two steps that are consistent with the places where the rim of the femoral head (step approximately 0.10 in.) and the sleeve (step approximately 0.03 in.) made contact.The head, which is made of cobalt chrome (astm f-75), shows no wear at the point of contact, but the stem shows considerable metal loss.
Event or Problem Description
Revision surgery: surgery performed to revise acetabular components.Proximal stem geometry was found to be notched.Stem removal performed.

• Brand Name: UNIPOLAR HIP
• Common Device Name: SLEEVE, UNIPOLAR, OFFSET -3.5
• Manufacturer (Section D): ENCORE MEDICAL L.P.; 9800 metric blvd; austin, tx 78758-5445
• MDR Report Key: 9678457
• Report Number: 1644408-2020-00070
• Device Sequence Number: 10888220
• Product Code: KWL
• UDI-Device Identifier: 00888912023412
• UDI-Public: (01)00888912023412
• Combination Product (Y/N): N
• Initial Reporter Country: US
• PMA/510(K) Number: K973614
• Number of Events Summarized: 1
• Summary Report (Y/N): N
• Device Implanted Year: 2007
• Device Explanted Year: 2019
• Reporter Type: Manufacturer
• Report Source: company representative
• Initial Reporter Occupation: Non-Healthcare Professional
• Type of Report: Initial
• Report Date (Section B): 02/06/2020

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?: No
• Operator of Device: Health Professional
• Device Expiration Date: 03/31/2012
• Device Model Number: 411-00-035
• Device Catalogue Number: 411-00-035
• Device Lot Number: 289392
• Was Device Available for Evaluation?: Yes
• Type of Report(Section G): Thirty-Day
• Initial Date Received by Manufacturer: 01/16/2020
• Initial Report FDA Received Date: 02/06/2020
• Is This a Single-Use Device that was Reprocessed and Reused on a Patient? (Y/N): No
• Patient Sequence Number: 1
• Outcome Attributed to Adverse Event: Required Intervention
• Patient Age: 57 YR