Devices › Prosthesis, knee, femorotibial, unicompartmental, semi-constrained, metal/polymer, mobile bearing
Device brand name · Knee prosthesis
Unknown Oxford Bearing: medical device reports filed with FDA
481 reports name it, 2017–2026. Manufacturer given most often on reports: Biomet UK. Product code NRA.
- 481
- device reports naming the brand
- 0% of all MAUDE reports · about 51 a year
- 42
- reports, 12 months to August 2026
- 72 in the 12 months before
- 0.2%
- classified as malfunction
- 3.8% across the product code
- 0.4%
- classified as death, as reported
- 2 reports · not verified by FDA
FDA's MAUDE database holds 481 reports that name the brand "Unknown Oxford Bearing" (knee prosthesis), received between February 2017 and August 2026; the manufacturer given most often on reports is Biomet UK. Spellings of one product vary from report to report.
42 reports arrived in the 12 months to August 2026, down 42% from 72 in the 12 months before. FDA releases MAUDE data monthly; reports can arrive months after an event, so the newest months grow in later releases. The event types recorded are injury (99.4%), death (0.4%) and malfunction (0.2%); across all prosthesis, knee, femorotibial, unicompartmental, semi-constrained, metal/polymer, mobile bearing reports (product code NRA) death is recorded in 1.1% and malfunction in 3.8%. Event type is the reporter's classification of the report, not a verified outcome.
The device problems coded most often are device dislodged or dislocated (24.1%), insufficient device problem information (21.6%) and fracture (4%). The patient problems coded most often are joint dislocation, pain and failure of implant. FDA states that "MDR data alone cannot be used to establish rates of events, evaluate a change in event rates over time or compare event rates between devices. The number of reports cannot be interpreted or used in isolation to reach conclusions about the existence, severity, or frequency of problems associated with devices." It adds that the reporting system "has limitations, including the potential submission of incomplete, inaccurate, untimely, unverified, or biased data."
Reports by month, five years
Reports by the month FDA received them. FDA releases MAUDE data monthly; reports can arrive months after an event, so the newest months grow in later releases.
By year received
Event type and report source
Event type, as classified on the report
Who filed the report
Grey bar: all 5,163 reports carrying product code NRA. Event type is the filer's classification and is not verified by FDA.
Device problems coded
| Device problem (FDA code) | Reports | Share | Share across product code |
|---|---|---|---|
| Device dislodged or dislocated | 116 | 24.1% | 11.1% |
| Insufficient device problem information | 104 | 21.6% | 28.3% |
| Fracturea broken bone | 19 | 4% | 6% |
| Unintended movement | 19 | 4% | 0.6% |
| Mechanical problema mechanical problem | 14 | 2.9% | 1.2% |
| Unstable | 14 | 2.9% | 2.7% |
| Naturally worn | 11 | 2.3% | 2.1% |
| Breakthe device broke | 10 | 2.1% | 1.3% |
| Migration or expulsion of device | 10 | 2.1% | 4.2% |
| Material integrity problema problem with the device material | 4 | 0.8% | 1% |
| Loose or intermittent connection | 3 | 0.6% | 4.4% |
| Malposition of device | 3 | 0.6% | 1% |
| Patient device interaction problem | 3 | 0.6% | 2.9% |
| Loosening of implant not related to bone-ingrowth | 2 | 0.4% | 3.3% |
| Degraded | 1 | 0.2% | 0.3% |
| Improper or incorrect procedure or method | 1 | 0.2% | 0.2% |
| Inadequacy of device shape and/or size | 1 | 0.2% | 0.4% |
| Material erosion | 1 | 0.2% | 0.3% |
| Migrationthe device moved from where it was placed | 1 | 0.2% | 0.7% |
| Missing information | 1 | 0.2% | 0.1% |
FDA's device problem codes as entered on the report; one report can carry several. Generic codes such as "no apparent adverse event" are left out.
Patient problems coded
| Patient problem (FDA code) | Reports | Share |
|---|---|---|
| Joint dislocationa dislocated joint | 88 | 18.3% |
| Painpain, site not specified | 61 | 12.7% |
| Failure of implant | 20 | 4.2% |
| Bone fracture(s) | 10 | 2.1% |
| Damage to ligament(s) | 7 | 1.5% |
| Medical device site infectioninfection at the device site | 7 | 1.5% |
| Impaired healingslow healing | 6 | 1.2% |
| Thrombosis/thrombus | 5 | 1% |
| Arthritis | 4 | 0.8% |
| Hemarthrosis | 4 | 0.8% |
| Hematomaa collection of blood under the skin or in tissue | 4 | 0.8% |
| Joint laxity | 4 | 0.8% |
| Post operative wound infection | 4 | 0.8% |
| Appropriate clinical signs, symptoms and conditions term/code not available | 3 | 0.6% |
| Joint impingement | 3 | 0.6% |
Patient problem codes are present mainly in reports filed since 2019 and are often blank.
In context
| Measure | Unknown Oxford Bearing | Product code NRA | All MAUDE reports |
|---|---|---|---|
| Reports | 481 | 5,163 | 26,136,888 |
| Share of that pool | — | 9.3% | 0% |
| Classified as death, per 1,000 reports | 4 | 11 | 9 |
| Classified as injury | 99.4% | 94.9% | 36.2% |
| Classified as malfunction | 0.2% | 3.8% | 62.3% |
| Filed by the manufacturer | 100% | 99.6% | 94.9% |
Shares are of reports, not of devices in use. FDA states that "MDR data alone cannot be used to establish rates of events, evaluate a change in event rates over time or compare event rates between devices. The number of reports cannot be interpreted or used in isolation to reach conclusions about the existence, severity, or frequency of problems associated with devices." It adds that the reporting system "has limitations, including the potential submission of incomplete, inaccurate, untimely, unverified, or biased data."
Other brands with product code NRA
| Brand | Reports | Latest 12 months | Classified as death |
|---|---|---|---|
| Unknown Knee | 1,847 | 18 | 1.5% |
| Unknown Oxford Knee | 276 | 0 | 3.3% |
| Unknown Oxford Tibial Component | 347 | 32 | 0% |
| Unknown Oxford Femoral Component | 317 | 30 | 0.3% |
| Unknown Tibial Component | 832 | 200 | 0% |
| Unknown Bearing | 317 | 84 | 0.3% |
| Unknown Femoral Component | 642 | 90 | 0.3% |
| Unknown Articular Surface | 473 | 78 | 0% |
| Unknown Femoral | 204 | 27 | 0% |
| Unknown NexGen Articular Surface | 243 | 26 | 0% |
| Unknown Tibial Tray | 405 | 25 | 0.2% |
Ordered by report count for navigation only. FDA states that "MDR data alone cannot be used to establish rates of events, evaluate a change in event rates over time or compare event rates between devices. The number of reports cannot be interpreted or used in isolation to reach conclusions about the existence, severity, or frequency of problems associated with devices." It adds that the reporting system "has limitations, including the potential submission of incomplete, inaccurate, untimely, unverified, or biased data." FDA also states that "common products may have a higher number of adverse events due to the higher total number of people using the product."
Questions about Unknown Oxford Bearing reports
How many FDA reports name Unknown Oxford Bearing?
481 medical device reports in the openFDA MAUDE release of 28 Sep 2026, covering reports received through August 2026; 42 in the latest 12 months.
What kinds of events are reported?
injury (99.4%), death (0.4%) and malfunction (0.2%). "Event type" is how the report was classified when filed: death, injury, malfunction or other.
What device problems are coded?
device dislodged or dislocated (24.1%), insufficient device problem information (21.6%), fracture (4%), unintended movement (4%) and mechanical problem (2.9%). These are FDA's device problem codes as entered on the report.
Who files these reports?
manufacturer reports (100%). Manufacturers and user facilities are required to report; voluntary reports come from health professionals and the public.
Do these reports show that Unknown Oxford Bearing was at fault?
No. FDA states that "MDR data alone cannot be used to establish rates of events, evaluate a change in event rates over time or compare event rates between devices. The number of reports cannot be interpreted or used in isolation to reach conclusions about the existence, severity, or frequency of problems associated with devices." It adds that the reporting system "has limitations, including the potential submission of incomplete, inaccurate, untimely, unverified, or biased data." FDA adds that "a causal relationship cannot be established between product and reactions listed in a report."
How do I report a problem with a medical device?
Through FDA MedWatch (Form FDA 3500 for health professionals and consumers), or to the manufacturer. See the guide on how to report.
Where this comes from. Counts are built from the openFDA Device Adverse Event (MAUDE) bulk export released 28 Sep 2026, which holds reports FDA received through 31 Aug 2026. Brand, generic and manufacturer names are as written on the reports; product code names come from FDA's device classification. A report counts here when any device it lists carries this brand name after punctuation and capitalisation are normalised. No report narrative, lot number, patient detail or reporter identity is published. See the methodology and sources; FDA's record is authoritative, and corrections are handled within five working days.
Drug data (FAERS) through 30 Jun 2026; device data (MAUDE) through 31 Aug 2026. Not medical advice.