Rating arthritis

Do you have a request for an assessment involving the measurement of arthritis?

Make sure you are using standard x-rays, as recommended in paragraph 3.28 (pp29-30 Impairment Assessment Guidelines (PDF, 1194 KB)). If you don’t have one, you can’t rate arthritis. Remember, for the knee, the person should be standing.

For a fair assessment, X-rays used must be in accordance with section 17.2h in AMA5 (p544) and the Impairment Assessment Guidelines (PDF, 1194 KB) (p29), and you should comment on whether this is so in the report – though other imaging modalities, clinical features and arthroscopy reports can support the diagnosis, they do not provide the objective data required to apply T17-31 and cannot be used.

You should also make a comparison with the contralateral side to ensure an objective rating is made for any pre-existing condition.

If you consider that the worker will be disadvantaged due to the lack of available suitable x-rays, please discuss this with the requestor on receipt of the assessment request and review of the supplied evidence.

Pre-existing arthritis?

You should provide information about why you consider there to be either a pre-existing condition or no pre-existing condition. This decision should be based on cartilage loss, not symptoms.

Your assessment should set out the objective evidence that indicates a pre-existing impairment, and whether such objective evidence allows for an estimation of %WPI under the relevant guides, quoting the tables used to determine any such pre-existing impairment. Plain x-rays often exist at or soon after the injury and these provide a baseline that allows comparison.

If you determine that there is no pre-existing impairment, describe what evidence (not based solely on the examinee's verbal history that there was none) has been relied upon to ascertain that any pre-existing injury or condition has completely resolved without residual impairment.

It’s important to scrutinise all material available in the referral documentation (e.g. doctor's notes and previous imaging studies), and not simply depend upon the history given by the examinee.