USTAR II Knee System Trial Hinge Box: Incomplete Screw Assembly Risk
United Orthopedic Corp. recalls USTAR II Knee System Hinge Box Trial models due to incomplete screw assembly preventing proper stem trail. Affected units include specific model numbers and lot codes.
Lower-risk recall
Due to an incomplete process of the component screw by a subcontractor which prevents the properly assembling of stem trail.
What happened, in plain English
United Orthopedic Corp. is recalling USTAR II Knee System Hinge Box Trial models (left and right) because a subcontractor's incomplete screw process may prevent proper assembly. This could lead to improper knee joint function during surgery. Read more at govinfonow.com/recall/314548-ustar-ii-knee-system-trial-hinge-box-incomplete-screw-assembly.
Source Summary by GovInfoNow · govinfonow.com/recall/314548-ustar-ii-knee-system-trial-hinge-box-incomplete-screw-assembly · Updated August 18, 2026 · FDA enforcement record: FDA #Z-2884-2026
Cite this page
“USTAR II Knee System Trial Hinge Box: Incomplete Screw Assembly Risk.” GovInfoNow, updated August 18, 2026. https://govinfonow.com/recall/314548-ustar-ii-knee-system-trial-hinge-box-incomplete-screw-assembly. Based on FDA recall #Z-2884-2026 (https://api.fda.gov/device/enforcement.json?search=recall_number:%22Z-2884-2026%22&limit=1).
Why it’s dangerous
The component screw was not fully processed by a subcontractor, which means the hinge box may not assemble correctly with the stem. This could cause improper alignment of the knee joint during surgery, potentially leading to complications.
Who’s affected
Patients who received the recalled USTAR II Knee System Hinge Box Trial models (left and right) during surgery are most at risk. The recall affects specific model numbers and lot codes used in knee replacement procedures.
How to tell if you have this one
Check if your USTAR II Knee System Hinge Box Trial has model numbers 9325-5711 to 9325-5716 or 9325-5721 to 9325-5726. Lot numbers 25FB41 to 25FB46 are also affected.
- Brand
USTAR II- Category
Medical device
All 4 products in this recall
FDA lists each product line separately under one recall event. Check your product description, lot or code numbers against each row. Every row shares the hazard and remedy on this page.
- Classification
Class II- Status
Ongoing- Distribution
US Nationwide distribution in the states of Texas and Michigan.
| Recall number | Product, codes & lots |
|---|---|
| Z-2883-2026 | Brand Name: U2 Total Knee System Product Name: PSA Box Trial, L, #1-6 and PSA Box Trial, R, #1-6 Model/Catalog Number: 9323-5511 thru 9323-5516 and 9323-5521 thru 9323-5526 Software Version: N/A Product Description: Knee femur prosthesis trial, reusable Component: No, N/A; Product Number; UDI-DI Code; Lot Code: Product Number 9323-5511; UDI-DI 04719886906929; Lot number 25FB54 Product Number 9323-5512; UDI-DI 04719886906936; Lot number 25FB55 Product Number 9323-5513; UDI-DI 04719886906943; Lot number 25FB56 Product Number 9323-5514; UDI-DI 04719886906950; Lot number 25FB57 Product Number 9323-5515; UDI-DI 04719886906967; Lot number 25FB58 Product Number 9323-5516; UDI-DI 04719886906424; Lot number 25FB59 Product Number 9323-5521; UDI-DI 04719886906974; Lot number 25FB29 Product Number 9323-5522; UDI-DI 04719886906981; Lot number 25FB30 Product Number 9323-5523; UDI-DI 04719886906998; Lot number 25FB31 Product Number 9323-5524; UDI-DI 04719886907001; Lot number 25FB32 Product Number 9323-5525; UDI-DI 04719886907018; Lot number 25FB33 Product Number 9323-5526; UDI-DI 04719886907025; Lot number 25FB34 |
| Z-2884-2026 | Brand Name: USTAR II Knee System Product Name: Hinge Box Trial, L, #1-6 and Hinge Box Trial, R, #1-6 Model/Catalog Number: 9325-5711 thru 9325-5716 and 9325-5721 thru 9325-5726 Software Version: N/A Product Description: Knee femur prosthesis trial, reusable Component: No, N/A; Product Number; UDI-DI Code; Lot Code: Product number 9325-5711; UDI-DI 04719886907032; Lot number 25FB41 Product number 9325-5712; UDI-DI 04719886907049; Lot number 25FB42 Product number 9325-5713; UDI-DI 04719886907056; Lot number 25FB43 Product number 9325-5714; UDI-DI 04719886907063; Lot number 25FB44 Product number 9325-5715; UDI-DI 04719886907070; Lot number 25FB45 Product number 9325-5716; UDI-DI 04719886907087; Lot number 25FB46 Product number 9325-5721; UDI-DI 04719886907094; Lot number 25FB35 Product number 9325-5722; UDI-DI 04719886907100; Lot number 25FB36 Product number 9325-5723; UDI-DI 04719886907117; Lot number 25FB37 Product number 9325-5724; UDI-DI 04719886907124; Lot number 25FB38 Product number 9325-5725; UDI-DI 04719886907131; Lot number 25FB39 Product number 9325-5726; UDI-DI 04719886907148; Lot number 25FB40 |
| Z-2885-2026 | Brand Name: U2 Total Knee System Product Name: Femoral valgus adaptor, left and right Model/Catalog Number: 9323-5333 and 9323-5334 Software Version: N/A Product Description: Manual Orthopedic Surgical Instrument Component: No; Product Number; UDI-DI Code; Lot Code: Product number 9323-5333; UDI-DI 04719886908084; Lot number 25FB50 Product number 9323-5334; UDI-DI 04719886908091; Lot number 25FB51 |
| Z-2886-2026 | Brand Name: U2 Total Knee System Product Name: Femoral valgus offset adaptor, 2mm, 4mm, 6mm, left and Femoral valgus offset adaptor, 2mm, 4mm, 6mm, right Model/Catalog Number: 9323-5335, 9323-5337, 9323-5339 and 9323-5336, 9323-5338, 9323-5340 Software Version: N/A Product Description: Manual Orthopedic Surgical Instrument Component: No; Product Number; UDI-DI Code; Lot Code: Product number 9323-5335; UDI-DI 04719886906554; Lot number 25FB64 Product number 9323-5337; UDI-DI 04719886906578; Lot number 25FB48 Product number 9323-5339; UDI-DI 04719886906592; Lot number 25FB52 Product number 9323-5336; UDI-DI 04719886906561; Lot number 25FB65 Product number 9323-5338; UDI-DI 04719886906585; Lot number 25FB49 Product number 9323-5340; UDI-DI 04719886906608; Lot number 25FB53 |
What to do — step by step
Check Product Details
Verify your USTAR II Knee System Hinge Box Trial model and lot number against the listed numbers to confirm if it's affected.
Where it went and when
Where it was distributed
Distributed nationwide; the notice names 2 states.
FDA distribution: “US Nationwide distribution in the states of Texas and Michigan.” States read from FDA’s own wording; “not listed” means the notice does not name it.
Named in the notice: Michigan, Texas.
Recall timeline
FDA published this recall 3 months after the firm started it.
- Firm started the recall
- FDA classified it Class II
- Published in FDA’s Enforcement Report
- Added to GovInfoNow
Dates from the agency record only; steps without a date are left out.
Questions people ask
Do I need to do anything if I have this product?
The recall does not require immediate action; you should check your product details to confirm if it's affected.
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Where this comes from
The facts (hazard, remedy, dates, manufacturer) are pulled from the official FDA recall record. The plain-language summary and step-by-step checklist are written by GovInfoNow to make the official notice easier to act on — they don’t replace it.
- Official source: FDA Recall #Z-2884-2026 (May 20, 2026) — FDA publishes no per-recall page; this is the official machine-readable enforcement record. Search FDA recalls for Z-2884-2026 to see it in context.
- Plain-language summary written by qwen3:4b on August 18, 2026, from the official record above. Not reviewed by a person — if it conflicts with the FDA notice, the notice is correct. Report an error on this page.
- GovInfoNow is an independent service and is not a government agency. We republish official FDA recall data; we don’t issue, amend or administer recalls.