MAUDE Adverse Event Report: SMITH & NEPHEW ORTHOPAEDICS LTD BHR ACETABULAR CUP 50MM; PROSTHESIS, HIP, SEMI-CONSTRAINED, METAL/METAL, RESURFACING

Catalog Number 74120150

Device Problems Patient-Device Incompatibility (2682); Insufficient Information (3190); Appropriate Term/Code Not Available (3191)

Patient Problems Debris, Bone Shedding (1803); Failure of Implant (1924); Toxicity (2333); Injury (2348); Osteolysis (2377)

Event Date 07/27/2015

Event Type  Injury  

Event Description

It was reported that left hip revision surgery was performed due to elevated levels of cobalt and chromium and development of bone destruction.

Manufacturer Narrative

[(b)(4)].

Manufacturer Narrative

A bhr head (74121142, 30998 sn (b)(4) ¿ details partially visually confirmed) and bhr cup (74120150, laser marked as 22404 040) were received for investigation following left hip revision surgery for elevated levels of cobalt and chromium and bone destruction.The production records were reviewed for the devices.During the review it was noted that the bhr cup is etched with batch number 22404 but due to rework the chart stick identifies the part as with batch number 26199.All the released devices involved met manufacturing specifications at the time of production visual inspection was carried out on the returned devices.A wear patch was observed on the bearing surface of the bhr head.Fine scratches were noted on the bearing surface of the bhr cup.Wear analysis was performed to review linear wear on the bearing surface of the bhr head and bhr cup.The wear images a wear patch on the bearing surface for the head, and a wear patch on the bhr cup that indicates edge loading.Maximum linear wear for the bhr head was 45.9¿m.On the bhr cup maximum linear wear was 53.2¿m, for a combined head & liner maximum wear of 99.1¿m.The maximum combined linear wear on the bearing surface was 99.1 ¿m.Based on historic wear data, after 10.2 years in vivo, the measured combined linear wear for this device is higher than the expected wear for a non-edge loaded smith and nephew large diameter metal-on-metal device.The position of wear on the acetabular cup shows that edge loading has occurred.The available medical documents were reviewed.Review of the provided surgical report from the implantation indicates that the superior femoral neck was notched minimally.A provided report dated 4 months before the revision indicates that blood cobalt (12 ¿g/l) was elevated with respect to reference.A ct and an mri report both dated approximately 3 months before the revision indicate that there were subchondral cysts at the acetabulum and defects at the peg of the femoral component that extended into the intertrochanteric region.Only a discharge report was provided related to the revision.It contained no information that could explain or help determining the causes leading to this revision.Retrieval analysis indicated that wear was higher than expected and that edge loading occurred.The cause for the reported cysts and bone defects remains unclear without histopathological analysis.A relation between the elevated cobalt concentrations and the increased amount of wear from the articulating surface cannot be excluded.At that time, the contralateral right hip was also replaced by a bhr resurfacing that could have contributed to the cobalt concentration.Whether the bone defects led to a reduced fixation of the implant remains unknown.As no x-rays were provided, a potential involvement of the implant position with the edge loading and increased amount of wear cannot be excluded based on this investigation the root cause of the reported revision could not be determined conclusively.However, the position of the wear indicates that edge loading has occurred, which could explain the wear observed.If additional information become available in the future, this case will be reopened.No preventative or corrective action has been initiated as a result of this investigation.

• Brand Name: BHR ACETABULAR CUP 50MM
• Type of Device: PROSTHESIS, HIP, SEMI-CONSTRAINED, METAL/METAL, RESURFACING
• Manufacturer (Section D): SMITH & NEPHEW ORTHOPAEDICS LTD; aurora house; spa park; leamington spa CV31 3HL; UK CV31 3HL
• MDR Report Key: 7086221
• MDR Text Key: 93821236
• Report Number: 3005975929-2017-00439
• Device Sequence Number: 1
• Product Code: NXT
• UDI-Device Identifier: 03596010502568
• UDI-Public: 03596010502568
• Combination Product (y/n): N
• PMA/PMN Number: P040033
• Number of Events Reported: 1
• Summary Report (Y/N): N
• Report Source: Manufacturer
• Source Type: consumer,foreign,other
• Type of Report: Initial,Followup,Followup
• Report Date: 05/05/2019

1 Device was Involved in the Event

1 Patient was Involved in the Event

• Date FDA Received: 12/06/2017
• Is this an Adverse Event Report?: Yes
• Is this a Product Problem Report?: No
• Device Operator: Health Professional
• Device Expiration Date: 12/31/2007
• Device Catalogue Number: 74120150
• Device Lot Number: 26199
• Was Device Available for Evaluation?: No
• Date Manufacturer Received: 11/21/2017
• Patient Sequence Number: 1
• Treatment: FEMORAL HEAD, # 74121142, LOT # 30998; FEMORAL HEAD, # 74121142, LOT # 30998
• Patient Outcome(s): Hospitalization; Required Intervention
• Patient Age: 60 YR