MAUDE Adverse Event Report: Medacta International SA AMIStem H Femoral Stems; AMIStem-H Lat. size 7

Model Number	01.18.147
Medical Device Problem Code	Osseointegration Problem (3003)
Health Effect - Clinical Code	Aseptic loosening (4883)
Date of Event	08/26/2026
Type of Reportable Event	Serious Injury
Event or Problem Description
Revision surgery due to amistem h loosening.Multiple tests for infection were performed, all of which were negative.The stem was easily removed manually by the surgeons, without the need for any extraction devices.A cemented competitor`s stem was successfully implanted.
Additional Manufacturer Narrative
Batch review performed on 28 aug 2026 lot 178462: 15 items manufactured and released on 23-apr-2018.Expiration date: 2023-apr-05.No anomalies found related to the problem.To date, 10 items of the same lot have been sold with no similar reported event during the period of review.Investigation performed by r&d project manager from the informations and the images attached to the complaint, it is visible that the expianted stem is covered with patient blood.The ceramic femoral head is attached to the stem taper.Looking at the stem body some white spots are visible on its surface.It is not possible to identify if these sposts are ha or bone residual, or a combined effect.Absorption of ha from the stem body can indicate that metabolic activity was taking place and that, presumably, adequate bone contact was achieved at the time of surgery.The post-op x-ray analysis could possibly provide more insight, such as the evaluation of possible early rotational instability or initial stress-shielding.Some signs of minor damage and scratches are present on the neck of the explanted stem, which is likely due to the revision surgery and not relevant to the reported issue.Based on the analysis completed and information available, it is not possible to identify a root cause of the stem loosening reported.Clinical evaluation performed by medical affairs director approximately four years after primary cementless tha, the amistem h femoral stem was revised for loosening.Infection was reportedly investigated with multiple tests, all negative.The available radiographs show radiolucent lines at the stem-bone interface, particularly in the proximal femur, compatible with impaired fixation.No serial radiographic history is available to reliably assess progressive subsidence or migration.At revision, the stem could reportedly be removed manually without extraction instruments, further supporting limited osseointegration.Aseptic loosening of a cementless stem is a known complication and may result from a multifactorial process, including patient-specific biological factors and failure to achieve or maintain adequate osseointegration.The precise mechanism cannot be determined with the information at hand, and the device was not available for direct investigation.There are no elements suggesting a defective or malfunctioning device.Root cause:aseptic loosening is a possible literature-described adverse event after primary hip arthroplasties and causes are often unknown.There is no indication that any potential issue with the device may have caused or contributed to the event.

• Brand Name: AMIStem H Femoral Stems
• Common Device Name: AMIStem-H Lat. size 7
• Manufacturer (Section D): Medacta International SA; strada regina; castel san pietro 6874 ; SZ 6874
• Manufacturer Contact: marco giannessi ; strada regina; castel san pietro 6874 ; SZ 6874
• MDR Report Key: 50692324
• Report Number: 3005180920-2026-00924
• Device Sequence Number: 21231379
• Product Code: LZO
• UDI-Device Identifier: 07630030804236
• UDI-Public: 07630030804236
• Combination Product (Y/N): N
• PMA/510(K) Number: K093944
• Number of Events Summarized: 1
• Summary Report (Y/N): N
• Device Implanted Year: 2022
• Device Explanted Year: 2026
• Serviced by Third Party (Y/N): N
• Reporter Type: Manufacturer
• Report Source: Company Representative
• Type of Report: Initial
• Report Date (Section B): 09/09/2026

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: 04/05/2023
• Device Model Number: 01.18.147
• Device Lot Number: 178462
• Was Device Available for Evaluation?: No
• Type of Report(Section G): Thirty-Day
• Initial Date Received by Manufacturer: 08/26/2026
• Initial Report FDA Received Date: 09/09/2026
• Was Device Evaluated by Manufacturer? (Y/N): Device Not Returned to Manufacturer
• Date Device Manufactured: 04/23/2018
• 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
• Outcome Attributed to Adverse Event: Required Intervention
• Patient Age: 68 YR
• Patient Sex: Male
• Patient Weight: 209 LB