Rising Knee Scan Rates Raise Concerns About Osteoarthritis Care
12 Nov 2026
A new report from the Australian Commission on Safety and Quality in Health Care (ACSQHC) has found a sharp rise in knee imaging among people aged 45 and over.
The Atlas Focus Report: Osteoarthritis of the Knee examined Medicare-funded imaging and hospital data. It also looked at rates of knee arthroscopy and knee replacement surgery.
The report found that CT knee scans increased by 83% over five years, rising from 261 to 478 scans per 100,000 people in 2023–24.
Knee ultrasounds also increased by 26%, while knee replacement surgery rose by 17% over the past decade.
The report warned that unnecessary imaging could lead to further referrals, additional tests and surgery that patients may not need.
The reasons behind the increase are not recorded in Medicare data. However, the report identified several possible factors, including patient expectations, time pressure, fear of missing other conditions and doctors' lack of confidence in diagnosing osteoarthritis without imaging.
Dr Phoebe Holdenson Kimura, Medical Advisor at the ACSQHC and a practising GP, said the increase in CT scans and ultrasounds was particularly concerning.
She explained that doctors can often diagnose knee osteoarthritis through a detailed patient history and physical examination, without needing imaging when there are no warning signs of other conditions.
The RACGP's guidelines for managing hip and knee osteoarthritis also state that imaging has a limited role in diagnosis. It may be considered when doctors suspect a condition other than osteoarthritis.
The ACSQHC report highlighted the need to improve access to first-line treatment before patients are referred for specialist care.
It identified barriers such as the cost of private physiotherapy, long waiting times for rheumatologists and delays in accessing public hospital surgery.
Exercise and weight management are among the recommended first-line treatments for knee osteoarthritis. Knee replacement surgery should generally be considered when patients have severe, ongoing pain that affects their daily activities.
Dr Holdenson Kimura said a non-surgical approach can be effective when patients receive the right information and support. However, she noted that GPs often face time pressures, especially when patients have several health concerns.
She said a proper assessment, explaining the diagnosis and educating patients about treatment options can be difficult to complete during a standard 10-minute consultation.
Radiologist Associate Professor John de Campo from the University of Melbourne also questioned the growing use of CT scans and ultrasounds.
He said these scans do not provide more useful information about joint damage than X-rays. Imaging also cannot measure a patient's pain or show how far they can walk.
He added that MRI scans can identify several joint changes that may not be related to the patient's symptoms.
There were some positive findings in the report. Knee arthroscopy rates fell by around half over the 10 years to 2023–24, in line with guidelines advising against the procedure for uncomplicated knee osteoarthritis.
Medicare-funded knee MRI scans increased by just 6%. The report suggested that restrictions introduced in 2018 on GP referrals for knee MRIs may have contributed to the smaller increase.
Rising Knee Scan Rates Raise Concerns About Osteoarthritis Care
Source: Australian Commission on Safety and Quality in Health Care (ACSQHC) – Atlas Focus Report: Osteoarthritis of the Knee; newsGP.