In collaboration with ExplantLab, we are introducing Orthotype to identify patients who may be at risk of, or experiencing, an adverse reaction to the cobalt chrome alloy used in many orthopaedic implants.

What is Orthotype

Orthotype is a novel Human Leukocyte Antigens (HLA) based algorithmic test that has been developed by ExplantLab and registered for clinical use with the Medicines and Healthcare products Regulatory Agency (MHRA), UK. 

1 in 6 people carry an HLA genotype which places them at higher risk of a metal hypersensitivity reaction.

Download the Orthotype flyer (PDF 2MB)

Three tests are available


Results from a genetic test to identify if patients carry the ‘at risk’ HLA genotype for a potential reaction to cobalt chrome, plus the patients’ demographic factors, are combined in an algorithm to identify the patients’ overall risk of metal hypersensitivity. This can help guide prosthesis selection to minimise risk of an adverse reaction to an orthopaedic implant. 


For patients presenting with chronic pain post-implant, the Orthotype genetic test and algorithm are combined with cobalt chrome blood levels to provide a highly specific and sensitive test to detect an active Adverse Reaction to Metal Debris (ARMD) as a potential contributing factor, and guide management decisions. 

Post-op Plus

Orthotype Post-Op Plus combines our standard post-op test with an additional blood metal ion test to measure the concentration of titanium ions in a patient’s blood enabling the treating physician to also detect the presence of increased wear or loosening of a titanium component. 

How do I make a referral?

If you are referring samples for the first time, please email the laboratory using nhsbthiserologyfilton@nhs.net prior to sending the samples.

Complete the test request form (PDF 151KB), indicating if a pre-operative evaluation for implant testing or post-operative monitoring is required. Please follow our guidance information (PDF 554KB) for completing the Orthotype test request form. If you do not send a fully completed test request form with the sample, this will delay testing and reporting of the results.

It is the responsibility of the person completing the test request form, to ensure they obtain informed consent.

Information for patients on the Orthotyptest and data privacy is available: Orthotype™ patient information sheet (PDF 338KB).

Sample requirements

  • 2 x 6ml EDTA samples are required for pre-operative evaluation for implant
  • 3 x 6ml EDTA samples are required for post-operative monitoring

Sending samples

You may send samples using a carrier of your choice or use our routine transport runs which deliver / collect from your blood bank.

You are responsible to ensure samples are packaged in accordance with the current European agreement concerning Carriage of Dangerous Goods by Road Regulations and IATA (packaging instructions PI650) to prevent breakage or spillage in transit. 

Please use our ready-formatted address labels (Word 59KB).

Alternatively, label the sample package using the address provided below:

H&I Department
500 North Bristol Park
BS34 7QH

When your samples have been dispatched; please send another email to the laboratory and include the package tracking number, if appropriate.

Email: nhsbthiserologyfilton@nhs.net

Test results

We email a report to the person identified on the test request form within:

  • 12 working days of referral for pre-operative evaluation
  • 20 working days of receipt of samples in the laboratory for post-operative monitoring

Please see below examples of Orthotype reports: 

Contact us

If you'd like to find out more please email: HINatnl@nhsbt.nhs.uk