MAUDE Adverse Event Report: SMITH & NEPHEW, INC. LGN CR HIGH FLEX XLPE SZ 1-2 9MM; PROSTHESIS, KNEE, PATELLOFEMOROTIBIAL, SEMI-CONSTRAINED, CEMENTED, POLYMER/METAL

Catalog Number	71453101
Medical Device Problem Codes	Material Erosion (1214); Material Deformation (2976)
Health Effect - Clinical Codes	Nerve Damage (1979); Metal Related Pathology (4530); Unequal Limb Length (4534); Joint Impingement (4834)
Date of Event	01/09/2025
Type of Reportable Event	Serious Injury
Event or Problem Description
It was reported that, after a b/l tkr performed on (b)(6) 2019, the patient experienced posteromedial swelling in her left knee on (b)(6) 2023, which gradually progressed.On (b)(6) 2024, the patient developed left-sided foot drop.It was found that the patient had an extensive implant wear with extensive foreign body reaction (wear particle) in the form of multi-loculated cysts in the posteromedial and posterior part of the knee crossing the midline.This adverse event was solved by revision surgery on (b)(6) 2025 in which one (1) unkn legion total knee prim tib insert xlpe, one (1) oxinium legion cr femur, sz 0 lt and one (1) unkn legion total knee prim tib baseplate were explanted, followed by popliteal cyst(s) excision and perineal nerve decompression on (b)(6) 2025.The patient's current health status is unknown.
Additional Manufacturer Narrative
H10: internal complaint reference: (b)(4).H3, h6: this complaint was opened by smith+nephew to document a patient complication reported that includes reference to the use of a smith+nephew product without evidence about a specific product problem.The reported complication relates to known inherent procedural risks that are appropriately documented in our risk files.Smith+nephew will continue to monitor trends in accordance with our post-market surveillance process and take necessary action as required if anticipated severity and/or occurrence rates are exceeded.Smith+nephew has no reason to suspect that the product failed to meet any specifications at the time of manufacture.Based on our review of all currently available information, we are unable to confirm a relationship between the reported event and the device or identify a definitive root cause.However, as the use of our product cannot be excluded as a potential cause or contributory factor to the reported issue, we are submitting this report in accordance with applicable regulations.If additional investigative findings or information becomes available that alters the conclusions of this report, a follow-up report will be submitted as required.
Event or Problem Description
It was reported that, after a b/l tkr performed on (b)(6) 2019, the patient experienced posteromedial swelling in her left knee on (b)(6) 2023, which gradually progressed.In nov-2024 the patient developed left-sided foot drop.It was found that the patient had an extensive implant wear with extensive foreign body reaction (wear particle) in the form of multi-loculated cysts in the posteromedial and posterior part of the knee crossing the midline.This adverse event was solved by revision surgery on (b)(6) 2025 in which one (1) lgn xlpe dished isrt sz 1-2 9mm, one (1) legion cr oxin fem sz3 lt and one (1) gns ii cmt tib size 2 {} left were explanted, followed by popliteal cyst(s) excision and perineal nerve decompression on (b)(6) 2025.The patient's current health status is unknown.
Additional Manufacturer Narrative
Additional information: a1, d4 (catalog number, lot number, expiration date, unique identifier (udi) #), d10, e1 (name prefix/title), g3/g4 (pma/510(k)number), h4.Corrected data: b5, d1.
Additional Manufacturer Narrative
Corrected data: b5.
Event or Problem Description
It was reported that, after a b/l tkr performed on (b)(6) 2019, the patient experienced posteromedial swelling in her left knee on (b)(6) 2023, which gradually progressed.In (b)(6) 2024 the patient developed left-sided foot drop.It was found that the patient had an extensive implant wear with extensive foreign body reaction (wear particle) in the form of multi-loculated cysts in the posteromedial and posterior part of the knee crossing the midline.This adverse event was solved by revision surgery on (b)(6) 2025 in which one (1) lgn cr high flex xlpe sz 1-2 9mm, one (1) legion cr oxin fem sz3 lt and one (1) gns ii cmt tib size 2 {} left were explanted, followed by popliteal cyst(s) excision and perineal nerve decompression on (b)(6) 2025.The patient's current health status is unknown.
Additional Manufacturer Narrative
Correction: a2: age.Additional information.H3,h6: the associated devices were returned and evaluated.The visual inspection revealed that the legion high flex insert significantly worn and discolored.One edge of the device has significant material loss and the post is no longer present.The insertion/extraction slot on the inferior surface is fractured and the lock detail is slightly deformed in several areas.The tibial baseplate was returned worn but intact; the femoral component was returned heavily damaged with significant material loss.The clinical/medical investigation concluded that, the reported patient fall in (b)(6) 2023 may have contributed to the adverse event through contact with a non-articulating surface, potentially involving third-body debris.Progressive swelling in the posteromedial area of the left knee reportedly began around the same time, eventually leading to left foot drop due to nerve impingement, as noted in the (b)(6) 2025 discharge summary (swelling for approximately 3 months, foot drop for 15 days).It is unclear whether the insert was properly locked during the revision procedure.While third-body particle abrasion remains a possible factor, the available information does not allow for a definitive conclusion regarding the clinical root cause.However, the duration between symptom onset, medical intervention, and revision surgery likely influenced the extent of component damage, soft tissue involvement, nerve compression, and metallosis.A review of the production orders did not reveal a manufacturing abnormality that could have caused or contributed to the reported incident.For the insert and tibial baseplate, a review of complaint history revealed a similar event for the listed part numbers over the previous 12 months, but no similar events for the batch based on the historical data, this failure mode will be monitored for future complaints for any necessary corrective actions.For the femoral component, a review of complaint history for the part number over the past 12 months and for the batch number based on historical data of the device did not reveal similar events for the listed device.A review of the instructions for use documents for knee systems revealed that possible adverse effects that wear of the polyethylene articulating surfaces of knee replacement components has been reported following total knee replacement.Higher rates of wear may be initiated by particles of cement, metal, or other debris which can cause abrasion of the articulating surfaces.Higher rates of wear may shorten the useful life of the prosthesis, and lead to early revision surgery to replace the worn prosthetic components.Additionally, revealed that, although rare, metal sensitivity or allergic reactions in patients following joint replacement have been reported.Implantation of foreign material in tissues can result in histological reactions involving macrophages and fibroblasts.A review of the risk management files revealed this failure mode was previously identified.The anticipated risk level is still adequate.A historical review concluded that there are no prior actions related to this products and event.At this time, we have no evidence to conclude that the product failed to meet any specifications at the time of manufacture.Factors that could contribute to the reported event include friction, joint tightness, patient anatomy, abnormal loading of limb, excessive forces and/or injury.Based on this investigation, the need for corrective action is not indicated.Should additional information be received, the complaint will be reopened.No further investigation is warranted for this complaint; however, we will continue to monitor for future complaints and investigate as necessary.We consider this investigation closed.

• Brand Name: LGN CR HIGH FLEX XLPE SZ 1-2 9MM
• Common Device Name: PROSTHESIS, KNEE, PATELLOFEMOROTIBIAL, SEMI-CONSTRAINED, CEMENTED, POLYMER/METAL
• Manufacturer (Section D): SMITH & NEPHEW, INC.; 1450 brooks rd.; memphis TN 38116
• Manufacturer (Section G): SMITH & NEPHEW, INC.; 1450 brooks rd.; memphis TN 38116
• Manufacturer Contact: holly topping ; 1450 brooks rd.; memphis, TN 38116 ; 5123913905
• MDR Report Key: 21845610
• Report Number: 1020279-2025-00648
• Device Sequence Number: 15778174
• Product Code: JWH
• UDI-Device Identifier: 00885556033432
• UDI-Public: 885556033432
• Combination Product (Y/N): N
• Initial Reporter Country: IN
• PMA/510(K) Number: K071071
• Number of Events Summarized: 1
• Summary Report (Y/N): N
• Device Implanted Year: 2019
• Device Explanted Year: 2025
• Serviced by Third Party (Y/N): N
• Reporter Type: Manufacturer
• Report Source: Other,Foreign,Health Professional,Company Representative
• Initial Reporter Occupation: Physician
• Type of Report: Initial,Followup,Followup,Followup
• Report Date (Section B): 09/05/2025

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 Catalogue Number: 71453101
• Device Lot Number: 18BM15413
• Was Device Available for Evaluation?: Device Returned to Manufacturer
• Is the Reporter a Health Professional?: Yes
• Type of Report(Section G): Thirty-Day
• Initial Date Received by Manufacturer: 03/25/2025
• Supplement Date Received by Manufacturer: Not provided; Not provided; 09/01/2025
• Initial Report FDA Received Date: 04/15/2025
• Supplement Report FDA Received Date: 04/30/2025; 07/04/2025; 09/05/2025
• Was Device Evaluated by Manufacturer? (Y/N): Device Not Returned to Manufacturer
• Date Device Manufactured: 02/21/2018
• Is the Device Labeled for Single Use? (Y/N): Yes
• Is This a Single-Use Device that was Reprocessed and Reused on a Patient? (Y/N): No
• Usage of Device: Initial
• Patient Sequence Number: 1
• Concomitant Medical Products and Therapy/Usage Dates: 71420162/18KM16059/GNS II CMT TIB SIZE 2 {} LEFT; 71421233/18JM01763G/LEGION CR OXIN FEM SZ3 LT
• Outcome Attributed to Adverse Event: Required Intervention; Other
• Patient Age: 60 YR
• Patient Sex: Female