La Trobe researchers have discovered that almost half the population has "creaky knees" in a study investigating how common the problem is and what it means for the health of our knees.
Knee crepitus, the audible crackling or grinding noise during knee movement, is common across all age groups but does not always reflect underlying knee problems.
La Trobe graduate researcher and physiotherapist Jamon Couch said people with creaky knees often felt there were more serious underlying health issues like arthritis, causing them to be fearful of exercising and using their knees.
"Health professionals often find it challenging to provide advice on the problem, owing to a lack of research on the meaning behind knee crepitus," Jamon said.
The research, published in the British Journal of Sports Medicinethis week, analysed the results of 103 studies involving more than 36,000 people and found that 41 per cent of the population had creaky knees.
"Knee crepitus was common in those with and without a knee injury. We discovered that 36 per cent of people without a knee injury had creaky knees, although it was far more common in those with an injury to their knee cartilage. We found that knee crepitus was present in 81 per cent of those with knee osteoarthritis," Jamon said.
"One of the more concerning discoveries we made was that people with knee crepitus were more than three times as likely to be diagnosed with osteoarthritis and twice as likely to exhibit knee joint changes linked to osteoarthritis on Magnetic Resonance Imaging (MRI) scans."
The cause of knee crepitus has been debated for decades, yet current evidence cannot confidently determine exactly why it occurs.
"Although investigation of the long-term consequences of knee crepitus is ongoing, people should generally not be concerned about their noisy knees and be encouraged to continue to exercise," Jamon said.
"If it's not painful, it's likely not doing any damage."