Assessment of the degree of permanent impairment where an upper limb arthroplasty has taken place
To provide decision makers with scheme guidance on the assessment of the degree of permanent impairment (PI), under section 24 of the Safety, Rehabilitation and Compensation Act 1988 (SRC Act), where an arthroplasty procedure1 of an upper limb has been undertaken.
Division 1 of the Guide to the Assessment of the Degree of Permanent Impairment (Approved Guide) does not provide impairment tables to assess the degree of PI where an arthroplasty procedure on an upper limb joint has been undertaken.
In these circumstances, the principles of assessment in Chapter 9 of the Approved Guide refer the decision maker to the American Medical Association’s Guides to the Evaluation of Permanent Impairment, 5th Edition (AMA5).
The Federal Court has previously considered shoulder arthroplasty assessment under the AMA52. Its decision provides guidance on how arthroplasty and associated upper extremity impairment (UEI) values are obtained under the AMA5 and then combined under the Approved Guide, to determine a single whole person impairment (WPI) value for the purpose of determining the degree of PI under the SRC Act.
As outlined above, the Approved Guide does not provide impairment tables to assess the degree of PI where an arthroplasty procedure on an upper limb joint has been undertaken. Where an employee has undergone an upper limb arthroplasty procedure, and is claiming a PI for that affected part of the limb, the following tables of the Approved Guide (Chapter 9) do not apply, and the decision maker should refer to the AMA5:
|Upper extremity tables||Affected joint|
Once the decision maker has obtained the AMA 5 UEI ratings for abnormal motion and arthroplasty they must be converted separately in to WPI values using the conversion table provided in the AMA5. Each WPI value obtained is then to be brought over to the Approved Guide and combined, using the Combined Values Chart.
The process for assessing the degree of PI value for an upper limb arthroplasty procedure is as follows:
Step 1: Use AMA5 to determine the impairment rating for abnormal motion and arthroplasty
- Determine the UEI rating for abnormal motion in accordance with Chapter 16—The Upper Extremities.
- Determine the UEI rating for arthroplasty in accordance with Chapter 16—The Upper Extremities.
Step 2: Use AMA5 to convert the UEI ratings to WPI
- Convert the individual UEI ratings for abnormal motion and arthroplasty into WPI values using Table 16-3.
Step 3: Use the Approved Guide to combine the WPI figures using the Combined Values Chart
- Combine the WPI rating for abnormal motion with the WPI rating for arthroplasty using the Combined Values Chart of the Approved Guide to calculate the total WPI for the upper extremity.
An employee has an accepted claim for a shoulder injury. An arthroplasty procedure is performed on their shoulder for which liability is accepted. Following the procedure, the employee continues to experience abnormal shoulder motion.
Following a period of recovery, the employee lodges a claim for permanent impairment in relation to the shoulder condition. The decision maker refers the employee to a Legally Qualified Medical Practitioner (LQMP) to assess their degree of PI under the SRC Act.
The assessor, using chapter 16 the AMA5, provides the following UEI information:
- UEI of 10% in respect of the arthroplasty. That number converts to a WPI rating of 6% in the AMA Guide
- UEI of 6% for the degree of abnormal motion. That number converts to a WPI rating of 4% WPI in the AMA Guide.
These two WPI ratings are then combined using the Combined Values Chart in the Approved Guide providing a final WPI rating of 10%. As this meets the minimum threshold for PI under section 24 the employee would be entitled to a PI and NEL payment under the SRC Act.
For further information regarding the Permanent Impairment provisions of the SRC Act see the scheme guidance on:
- Interest rate for late compensation payments for permanent impairment
- Assessing permanent impairment where multiple injuries are involved
Scheme e-guidance is also available through Comcare’s Learning Management System (LMS) on the permanent impairment provisions.
For further information, please contact Comcare’s Scheme Policy and Design team on 1300 366 979 or email: email@example.com.
 Arthroplasty (surgical repair of a joint) is an orthopaedic procedure where the articular surface of a musculoskeletal joint is replaced, remodelled, or realigned.
 Re Guppy v Australian Postal Corporation (2013) FCA 489 (8 May 2013)
This information is for: Government sector and self-insured licensees
Document number: SRC325
Last updated: March 2023
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