MAUDE Adverse Event Report: AESCULAP AG ENDURO MENISCAL COMPONENT F2 12MM; KNEE ENDOPROSTHETICS

Model Number NR881M

Device Problem Fracture (1260)

Patient Problem Failure of Implant (1924)

Event Type  Injury  

Manufacturer Narrative

Manufacturing site evaluation: investigation on-going.Additional information / investigation results will be provided in a supplemental report.

Event Description

It was reported that there was an issue with nr881m - enduro meniscal component f2 12mm.According to the complaint description, the nut broken after 9 years from the implantation.A revision surgery was necessary.Additional information was not provided.The adverse event is filed under aag reference: (b)(4).Involved components: nb015k - enduro femoral component cemented f2l - lot 51985355 (400587746).

Manufacturer Narrative

Investigation: visual investigation: the rotation axis locknut is broken into two pieces.This case was discussed with a specialist from the development department.We received the rotation axis locknut in a broken condition -> broken into two pieces.Due to the small area, a detailed fracture surface analysis/statement regarding type of breakage is hardly possible.Nevertheless the breakage surface regarding part a /part b shows no abnormalities like blow holes or foreign material inclusions.The thread of the locknut shows visible damages.Furthermore it could be determined that one part (part b) of the broken rotation axis locknut shows a visible deformation.X-ray images show a part of the nut which has detached from the axle and is now free in the area of the joint.Device history records: the device quality and manufacturing history records (dhr) have been checked for all leading device(s) lot numbers and the products found to be according to our specification valid at the time of production.The current failure rate is within the risk analysis and therefore acceptable; severity was 4(5) and probability 2(5).Explanation and rationale: on the basis of the current information a clear conclusion regarding the mentioned failure cannot be drawn.We assume that the rotation axis locknut has been loosened postoperatively over time and was therefore free in the area of the knee joint.Probably the loosened screw got under high pressure/load during joint movements, so that the breakage occurred.Regarding the root cause for the loosening of the rotation axis locknut from the axis, it could be said that generally the thread can only loosen when the taper connection has not been connected correctly.One reason for loosening the rotation axis locknut postoperatively could be: when the connection between the axis taper and the femur could not firmly fitted, there is a gap and hence movement between the components.This leads to the femur safety nut unscrewing or to the axis breaking above the taper.Due to the fact that the implant combination was in the patient for approximately 7 years, this is only hypothetical.An excessive/unusual load by the patient over a long time period could also be responsible for the loosening of the rotation axis locknut postoperatively.Conclusion/preventive measures: based upon the investigation results, a clear root cause conclusion regarding the mentioned failure cannot be drawn.There is no indication for a material-, manufacturing- or design-related failure.Based upon the investigation results, a capa is not necessary.

Event Description

Update: this product, nr881m, is now considered to be an involved component, and no longer leading material.Leading material: nb015k - enduro femoral component cemented f2l - lot 51985355 (400587746) - not sold in usa.Involved component: nr881m - enduro meniscal component f2 12mm - lot 52124877.

• Brand Name: ENDURO MENISCAL COMPONENT F2 12MM
• Type of Device: KNEE ENDOPROSTHETICS
• Manufacturer (Section D): AESCULAP AG; po box 40; tuttlingen, 78501 ; GM 78501
• Manufacturer (Section G): AESCULAP AG; po box 40; tuttlingen, 78501 ; GM 78501
• Manufacturer Contact: christian von der gruen ; po box 40; tuttlingen, 78501 ; GM 78501
• MDR Report Key: 16373162
• MDR Text Key: 309507304
• Report Number: 9610612-2023-00029
• Device Sequence Number: 1
• Product Code: KRO
• Combination Product (y/n): N
• Reporter Country Code: GM
• PMA/PMN Number: K101815
• Number of Events Reported: 1
• Summary Report (Y/N): N
• Report Source: Manufacturer
• Source Type: Company Representative
• Reporter Occupation: Other Health Care Professional
• Type of Report: Initial,Followup
• Report Date: 07/11/2023

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: Health Professional
• Device Expiration Date: 02/29/2020
• Device Model Number: NR881M
• Device Catalogue Number: NR881M
• Device Lot Number: 52124877
• Was Device Available for Evaluation?: No
• Is the Reporter a Health Professional?: Yes
• Initial Date Manufacturer Received: 01/24/2023
• Initial Date FDA Received: 02/14/2023
• Supplement Dates Manufacturer Received: 06/15/2023
• Supplement Dates FDA Received: 07/11/2023
• Was Device Evaluated by Manufacturer?: Device Not Returned to Manufacturer
• Date Device Manufactured: 03/13/2015
• 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
• Treatment: NB015K - LOT 51985355.; NR881M - LOT 52124877.
• Patient Outcome(s): Required Intervention
• Patient Weight: 103 KG