29 May 2017

Imaging on a knees-to-know basis only

Bones Clinical

The first clinical care standards for knee osteoarthritis have emphasised that imaging and arthroscopy are unnecessary in most cases.

Over two million Australians live with knee osteoarthritis but rates of knee surgery vary up to four-fold around the country.

The clinical care standards aimed to reduce unwarranted variation and promote shared decision-making, Associate Professor Michael Yelland, a member of the working group that developed the standards, said.

The clinical care standards were released in May by the Australian Commission on Safety and Quality in Health Care, and were endorsed by nine health and consumer organisations, including the Australian Rheumatology Association.

Professor Yelland, a general and musculoskeletal medicine practitioner and associate professor at Griffith University, said the standards contained two key messages for GPs.

The first was to limit imaging to cases where there was doubt about the diagnosis of knee osteoarthritis.

“You can make a diagnosis on clinical grounds in someone over the age of 50 years, such as pain, stiffness, tenderness, and swelling,” he said.

X-ray was useful only if an alternative diagnosis was suspected, such as a non-trauma fracture or malignancy, the clinical care standards stated.

MRI should only be reserved for cases where there was a suspicion of serious pathology not detected by X-ray.

“In the over 50 age group, a lot of findings [from X-ray and MRI] are coincidental and not of any clinical significance,” said Professor Yelland.

MRI might detect age-related degeneration in the menisci, which did not require surgery, he said. This finding might become a distraction and even a concern for the patient.

The second takeaway message for GPs was that conservative treatments should be exhausted before making a referral to a specialist.

Evidence showed that knee arthroscopy did not have a role to play in uncomplicated osteoarthritis of the knee. There were exceptions, particularly in younger age groups where there might be tears to ligaments or menisci.

“But most of the time knee arthroscopy is no better than a placebo treatment,” said Professor Yelland.

“[But] there is quite a big body of evidence that education, self-management and particularly weight loss and exercise are effective,” said Professor Yelland.

“For example, for every kilogram in weight that you lose, it takes four kilograms of stress off the knee.”

Some surgical procedures might be appropriate in cases where pain and disability could not be sufficiently alleviated, he said.

“There is certainly still a role for knee replacements in those who have tried a whole gamut of conservative therapies.”

To read the full clinical care standards: bit.ly/2r1XzQG