Implant manufacturers are invited to submit data regarding their orthopaedic implant products to ODEP in a defined format (an ODEP submission form). The Panel reviews this submission and rates the strength of the evidence presented by the manufacturer, resulting in the award (or not) of an ODEP rating.

Benchmarking starts before an implant is used in significant numbers. This is called the Pre-Entry stage. Full benchmarking starts at year 3 and manufacturers have to continue submitting data on a regular basis to achieve the higher benchmarks, as described below.

A lower ODEP rating number does not necessarily indicate that an implant is not as good as an implant with a higher number.  Rather, it means that there is not the number of years of use / evidence at that point in time to support a higher value.

Similarly, the letters “B”, “A” and “A*” refer to the strength of evidence provided by the manufacturer – with registry data typically carrying more weight than a peer reviewed publication, which in turn would carry more weight than an in-house manufacturer-initiated study.

Implants are expected to progress through the rating benchmarks from pre-entry through 3, 5, 7, 10, 13 and 15, as data becomes available.  Failure to follow this progression within a defined timescale will result in removal of a product’s ODEP rating.

ODEP reviews implant data at the product code (catalogue number) level.  This is to prevent “camouflage” where variants of implants can exist within a well-established brand name. For example, a “new” tray for a knee replacement may be introduced within a well-established brand name but might be reported as (for example) 3A rather than (for example) 10A of the more established implants within the brand.

The table below summarises the various elements involved in a single ODEP rating. NB! Please always refer to the full criteria for the relevant device when making a submission.

All ratings are updated at the end of each ODEP cycle, which typically occurs around 3–4 weeks after the appeal meeting. This includes ratings that were granted at the initial submissions review meeting as well as those granted at the appeals. This approach ensures fairness and consistency for all manufacturers. Manufacturers are requested to keep the latest ratings confidential until the official publication date. Digital certificates are usually issued after publication. All important dates are announced in the Events section of the ODEP website.

Unless otherwise specified, the 3-, 5, and 13-year ratings are valid for 2 years, and the 7-, 10- and 15-year ratings are valid for 3 years. ODEP may extend the validity of existing ratings by a 12-months’ “grace period”, to allow manufacturers to collect their clinical data that would demonstrate further progress through the benchmarks.

Products with the ODEP Pre-Entry status do not have the option of staying at Pre-Entry past 5 years unless the manufacturer can demonstrate exceptional circumstances. After 3 years manufacturers must produce annual data to confirm that the implant is not doing badly even if they do not have enough data to reach a year 3 benchmark.

The Pre-Entry A* status stays with the product as long as it is being monitored through the Beyond Compliance programme (unless the manufacturer progresses the implant through higher ODEP benchmarks, e.g. 3A, etc). If the product leaves Beyond Compliance before reaching the next benchmark, its rating is downgraded to the Pre-Entry status on the day of the withdrawal from Beyond Compliance.

Please note that there are also certain conditions, where ODEP requests a resubmission within 6 to 12 months’ time. This request is often made when the product’s confidence intervals are too close to the benchmark. If the Panel’s request is not met by the manufacturer and no submission is made within the specified period, the product’s rating will lapse, as no grace period applies in such cases.

If the panel become aware of a patient safety concern with a rated implant, they reserve the right to suspend the rating, pending investigation.  If that investigation, in consultation with the manufacturer, confirms that the clinical performance of the implant is not consistent with it continuing to hold an ODEP rating, the panel have the right to remove the rating, and mark the implant as Unacceptable or Withdrawn (as appropriate).

The validity of product ratings is provided to the manufacturers when new ratings are granted; it is also reflected on the ODEP website (see the “ODEP Ratings due for renewal” section of each product listing), and on the Digital Certificates.

In orthopaedics, and particularly in Knees, many implants have changed shape to become closer to average native knee anatomy and kinematics. The marketing adjectives used by industry to describe this, can cause confusion e.g. bespoke, personal, individualised, anatomic, patient specific. These terms have not defined implant classification or regulatory meaning. There are, however, two terms that do have specific definitions, namely Custom and Patient-Matched. 

“Custom” refers to a single implant made at the request and prescription of the surgeon to deal with a rare situation of abnormal anatomy e.g. dysplasia or fracture malunion, and under the MHRA rules it did not require a CE mark. It is not possible to provide an ODEP rating for these implants and ODEP believes that no other category of implant that is eligible for an ODEP rating, should use the term “custom/customised” in its product description or marketing.

“Patient Matched” refers to a hip or a knee replacement when the implant is intended for use in standard pathology (e.g. osteoarthritis) and anatomy and in large numbers. There is a process of acquiring more detailed anatomical information about the individual patient by means of x-rays and scans. A single femoral and tibial component are provided for use in theatre. Novel manufacturing techniques are used to either make the implants “from scratch” or to modify or select a best fitting implant for the individual from a very wide range of shapes within a specific design envelope. ODEP has decided to award Patient Matched ratings to enable clear description and outcome assessment of this group of implants that were previously not subjected to the same level of scrutiny as standard implants. Patient Matched ratings therefore provide an assessment of the process of producing the implant rather than just rating an implant. A Patient Matched rating does not imply any superiority over a standard ODEP rating. Implants that do not meet the above criteria are not eligible to apply for a Patient Matched rating. Patient Matched ratings are assessed at the same time periods and have to meet the same volume and revision-rate benchmarks as normal ODEP ratings. The same A*, A and B rating descriptions apply.

After the intended patient has had the imaging necessary to establish the anatomy of the joint being replaced, there are two methods of manufacturing the final product (see below). The final result is the same in that the design must stay within the design envelope which has been tested and approved by the regulatory body for the particular product. This means that the prosthesis is the closest approximation to the patient anatomy as allowed by the approved design envelope and such products can only be described as patient matched as that is the description as assigned by global regulatory bodies.

Products which are truly custom, patient specific or unique to an individual patient are examples of a totally different regulatory type. They should not be confused with patient matched implants which are actually a hybrid between off the shelf implants and implants individually made to be a perfect copy of the anatomy of an individual named patient.

ODEP recognises two types of Patient Matched implants:

Type 1: The implant is selected from a very large range of sizes and may have its shape slightly modified to better match the anatomy of the patient. This can only be done as long as the shape of the finished product stays within the design envelope for the brand which was approved by the regulatory body.

Type 2: The implant is individually designed and manufactured from scratch, often using additive layer manufacturing, but the design limitation of the finished product is exactly the same as described for type 1.

In summary – ODEP-rated Patient Matched (PM) implants must never be referred to as being Custom Made, Customised, Individualised, Patient specific etc as these are not the regulatory term which is used for this type of product and may cause confusion to medical professionals using the product or visiting the ODEP website.

The ODEP method has been specifically designed to maximise patient safety whilst recognising the need to support innovation. ODEP has two special categories for devices that have had insufficient use in the UK to support 3 years of evidence. The first is “Pre-entry”. This is not a benchmark rating.  Rather, it is where the manufacturer has obtained their UKCA/CE mark and has registered the implant with ODEP (in the expectation of applying for a benchmark rating at a future date).   The second category is “Pre-entry A*”. This is a benchmark rating that indicates that the device has achieved its UKCA/CE mark and is also going through the Beyond Compliance* process. 

This approach aims to help hospitals provide safe and effective care whilst also providing a means of continuous improvement.

*Beyond Compliance is a voluntary service evaluation programme manufacturers can elect to enter for their new or modified  orthopaedic implant, which closely monitors its performance during the early years of use, where data alone may provide insufficient evidence of safe use and closer engagement with implanting surgeons is also required.