MAUDE Adverse Event Report: United Orthopedic Corporation Conformity stem, #4; Prosthesis, Hip, Semi-Constrained, Uncemented, Metal / Polymer, Non-Porous, Calcium Phosphate

Catalog Number	1110-3004
Medical Device Problem Code	Loosening of Implant Not Related to Bone-Ingrowth (4002)
Health Effect - Clinical Codes	Arthralgia (2355); Metal Related Pathology (4530); Cartilage damage (4833); Aseptic loosening (4883)
Date of Event	08/21/2026
Type of Reportable Event	Serious Injury
Event or Problem Description
A complaint case regarding the conformity stem was received by the french branch on (b)(6) 2026.An 82-year-old female patient underwent tha on (b)(6) 2024, using a femoral head and conformity stem manufactured by united orthopedic corporation, along with a serf novae? dual mobility cup from another manufacturer.Approximately 1 year and 9 months after implantation, the patient developed hip pain.A ct scan revealed loosening of the femoral stem without an associated periprosthetic fracture.Further testing was performed to rule out infection as a potential cause of the loosening.A revision surgery was performed on (b)(6) 2026.Additionally, significant black deposits were observed around the loosened femoral stem intraoperatively.Histopathological analysis of the blackish soft tissue confirmed the diagnosis of metallosis.
Additional Manufacturer Narrative
For this event, an investigation into the united conformity stem and femoral head was conducted.The review confirmed that no relevant abnormal notes were identified in the production records of either product.The final product dimensions, appearance, and inspection values all complied with the specification requirements.In addition, the conformity stem has been marketed for more than seven years, with over (b)(4) units sold worldwide, while the u2 femoral head has been marketed for more than eight years, with over (b)(4) units sold worldwide.To date, no other similar abnormal feedback have been received.As of the reporting date, the products involved in the customer complaint have not yet been obtained.Based on our review of all currently available information, current evidence does not establish a causal relationship between the device and the reported event, and the definitive root cause could not be identified.A follow up report will be submitted if the complaint products are received and /or further investigation results are available.Product information of explant products: 1.United hip system conformity stem #4 (product number: 1110-3004 / lot number: 23f289b)(udi: (b)(4).2.United hip system u2 femoral head, ?28mm, -3mm (product number: 1206-1028 / lot number: 24a830r)(udi: (b)(4).

• Brand Name: Conformity stem, #4
• Common Device Name: Prosthesis, Hip, Semi-Constrained, Uncemented, Metal / Polymer, Non-Porous, Calcium Phosphate
• Manufacturer (Section D): United Orthopedic Corporation; no. 57., park ave 2; science park; hsinchu city, hsinchu city 30075 ; TW 30075
• Manufacturer Contact: lois ho ; no. 57., park ave 2; science park; hsinchu city, hsinchu city 30075 ; TW 30075
• MDR Report Key: 50865561
• Report Number: 9681642-2026-00035
• Device Sequence Number: 18806838
• Product Code: MEH
• UDI-Device Identifier: 04711605583213
• Combination Product (Y/N): N
• Initial Reporter Country: FR
• PMA/510(K) Number: K183312
• Number of Events Summarized: 1
• Summary Report (Y/N): N
• Device Implanted Year: 2024
• Device Explanted Year: 2026
• Serviced by Third Party (Y/N): N
• Reporter Type: Manufacturer
• Report Source: Health Professional,Distributor
• Initial Reporter Occupation: Physician
• Type of Report: Initial
• Report Date (Section B): 09/23/2026

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 Catalogue Number: 1110-3004
• Device Lot Number: 23F289B
• Was Device Available for Evaluation?: No
• Is the Reporter a Health Professional?: Yes
• Type of Report(Section G): Thirty-Day
• Initial Date Received by Manufacturer: 08/24/2026
• Initial Report FDA Received Date: 09/23/2026
• 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: Other; Required Intervention
• Patient Age: 82 YR
• Patient Sex: Female