MAUDE Adverse Event Report: MEDACTA INTERNATIONAL SA AMISTEM H FEMORAL STEMS; AMISTEM H CEMENTLESS STEM LATERALIZED SIZE 4

Model Number	01.18.144
Medical Device Problem Code	Fracture (1260)
Health Effect - Clinical Code	Insufficient Information (4580)
Date of Event	12/27/2024
Type of Reportable Event	Serious Injury
Additional Manufacturer Narrative
Batch review performed on 10 jan 2025.Lot 123816: (b)(4) items manufactured and released on 21-nov-2012.Expiration date: 2017-oct-31.No anomalies found related to the problem.To date, (b)(4) items of the same lot have been sold with no similar reported event since the lot has been released on the market.Clinical evaluation performed by medical affairs department: a revision surgery was performed due to a fracture of the neck of a stem implanted 10 years earlier in the context of a total hip arthroplasty.The available x-ray clearly confirms this implant breakage at the mid-neck.The patient's medical history indicates that a revision surgery was performed 2-3 years early.During this revision, the stem was not changed, but the femoral head and the cup was replaced.Given the access to the joint during the revision procedure, it is likely that the neck of the stem was damaged, potentially in an almost invisible manner, by surgical instruments, such as the electrocautery.This could have created an indentation in the neck, which may be the origin of a fatigue fracture.We are providing an estimation of a possible cause for this adverse event, as the broken device is currently not available for analysis.
Event or Problem Description
Revision surgery due to amistem-h breakage at about 10 years and 3 months from the primary.The patient had undergone a prior revision surgery (reason unknown) 2 years earlier, during which the head and cup were revised.The surgeon revised the stem with a competitor device.
Additional Manufacturer Narrative
Clinical evaluation performed by medical affairs department: a revision surgery was performed due to a fracture of the neck of a stem implanted 10 years earlier in the context of a total hip arthroplasty.The available x-ray clearly confirms this implant breakage at the mid-neck.The patient's medical history indicates that a revision surgery was performed 2-3 years early.During this revision, the stem was not changed, but the femoral head and the cup was replaced.Given the access to the joint during the revision procedure, it is likely that the neck of the stem was damaged[?]potentially in an almost invisible manner[?]by surgical instruments, such as the electrocautery.This could have created an indentation in the neck, which may be the origin of a fatigue fracture.This hypothesis could be confirmed after visual inspection of the explanted device, and the correspondence between the surface damage and the crack initiation site support this theory.This is a possible adverse event following revision of some components of the total hip that does not include removal of the stem, described in the scientific literature.Visual inspection performed by r&d project manager during the analysis it is evaluated that the neck of stem is fractured in two separated parts.Some signs of surface damage, such as scratches and burns, are visible on the neck area.It is unclear whether these marks are a result of intraoperative manipulation of the head or due to the revision surgery.Particularly, in the middle of the neck radius a scratch is present that is in correspondance of the stiration typical of a fatigue crack propagation visible in the fracture surface.On the lateral side the final part of the fracture shows dimpled ductile features typical of overload.It is possible that during the revision of the head the surgeon hit the neck surface with an instrument which caused the small scratch from which originated the fatigue crack propagation.Based on the available information, it is highly probable that the neck of the stem became damaged at the surface, possibly by interaction with a power source (i.E.Electrosurgical knife) or high-energy contact with hard objects (e.G.Surgical instruments).This is a plausible mechanism to create a microcrack in the neck, which is likely to be the origin of a fatigue fracture.The investigation does not indicate any potential manufacturing related issue or systemic deficiency.

• Brand Name: AMISTEM H FEMORAL STEMS
• Common Device Name: AMISTEM H CEMENTLESS STEM LATERALIZED SIZE 4
• Manufacturer (Section D): MEDACTA INTERNATIONAL SA; strada regina; castel san pietro, switzerland 6874 ; SZ 6874
• Manufacturer (Section G): MEDACTA INTERNATIONAL SA; strada regina; castel san pietro, switzerland 6874 ; SZ 6874
• Manufacturer Contact: marco giannessi ; strada regina; castel san pietro, switzerland 6874 ; SZ 6874
• MDR Report Key: 21311199
• Report Number: 3005180920-2025-00010
• Device Sequence Number: 21042345
• Product Code: LZO
• UDI-Device Identifier: 07630030804205
• UDI-Public: 07630030804205
• Combination Product (Y/N): N
• Initial Reporter Country: IT
• PMA/510(K) Number: K093944
• Number of Events Summarized: 1
• Summary Report (Y/N): N
• Device Implanted Year: 2014
• Device Explanted Year: 2024
• Serviced by Third Party (Y/N): Unknown
• Reporter Type: Manufacturer
• Report Source: Company Representative
• Initial Reporter Occupation: Non-Healthcare Professional
• Type of Report: Initial,Followup
• Report Date (Section B): 06/06/2025

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 Expiration Date: 10/31/2017
• Device Model Number: 01.18.144
• Device Lot Number: 123816
• Was Device Available for Evaluation?: Device Returned to Manufacturer
• Type of Report(Section G): Thirty-Day
• Initial Date Received by Manufacturer: 01/07/2025
• Supplement Date Received by Manufacturer: Not provided
• Initial Report FDA Received Date: 02/05/2025
• Supplement Report FDA Received Date: 06/06/2025
• Was Device Evaluated by Manufacturer? (Y/N): Yes
• Date Device Manufactured: 11/21/2012
• 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
• Outcome Attributed to Adverse Event: Required Intervention
• Patient Age: 80 YR
• Patient Sex: Male