Key takeaways

A Medical Appeal Panel (MAP) overturned a Medical Assessment Certificate (MAC) applying a 40% deduction under section 323, on the basis that although the applicant had significant pre-existing pathology, he was largely asymptomatic prior to the injury.

Brief facts

The applicant, a forklift driver, alleged an injury to his left knee due to the nature and conditions of his employment with the respondent.

The claim was initially disputed. However, in 2021, the Personal Injury Commission (PIC) found the respondent liable for the applicant’s left knee injury (aggravation of a disease process) and confirmed that a total left knee replacement was reasonably necessary.

The worker then underwent the left knee replacement surgery and eventually brought a claim for lump sum compensation. The matter proceeded to a Medical Assessor (MA), who assessed 20% Whole Person Impairment (WPI) but applied a 40% section 323 deduction, as the worker had previously injured his left knee in 2002 with an earlier employer.
The applicant appealed the MAC on the grounds that the assessment was based on incorrect criteria and contained a demonstrable error under section 327(3)(c) and (d) of the Workplace Injury Management and Workers’ Compensation Act 1998.

Judgment

The applicant contended that the MA had erred in applying section 323 and that the standard 10% deduction should apply, as there was little evidence of a symptomatic condition despite the prior left knee injury in 2002 (for which he had undergone partial meniscectomy surgery at the time).

The respondent submitted that there was sufficient evidence to warrant a 40% section 323 deduction, relying on a x-ray from 2020 showing extensive osteoarthritic changes in the left knee, and a surgeon’s report confirming advanced osteoarthritis.
The MAP rejected the respondent’s argument. It agreed a section 323 deduction was appropriate due to the earlier left knee injury and osteoarthritis but found 40% excessive, applying the standard 10% deduction. The MAP noted that while the applicant had pre-existing osteoarthritis of the left knee, there was little evidence that it was symptomatic prior to commencing employment with the respondent.

Implications

The presumption of a standard 10% deduction under section 323 is difficult to displace. Even with prior injury, surgery and medical evidence supporting significant pre-existing pathology, symptoms experienced by the worker are critical in determining whether a higher deduction is justified. There must be compelling evidence that the standard 10% deduction is ‘at odds with the available evidence’ under section 323.