The researchers looked at information from almost 4,500 Americans taking part in two arthritis studies. In one study, only 16 percent of patients with hip pain had X-ray evidence of osteoarthritis in the hip and only 21 percent of those with X-ray evidence of arthritis had hip pain.
In the other study, the rates were 9 percent and 24 percent, respectively, according to the findings reported recently in the journal BMJ.
"The majority of older subjects with high suspicion for clinical hip osteoarthritis did not have radiographic hip osteoarthritis, suggesting that many older persons with hip osteoarthritis might be missed if diagnosticians relied on hip radiographs to determine if hip pain was due to osteoarthritis," said study corresponding author Dr Chan Kim.
Kim is an instructor of medicine at Boston University School of Medicine.
A missed or delayed diagnosis of hip arthritis can have serious consequences. Up to 10 percent of patients with hip arthritis don't get enough exercise and are at increased risk for heart and lung disease, obesity, diabetes and falls, the researchers said.
"Given these findings, patients with suspected hip OA (osteoarthritis) should be treated regardless of X-ray confirmation," Kim said in a university news release.
Hip arthritis is a major health issue that causes pain and disability. Each year, more than 330,000 hip replacements are performed in the United States, according to the researchers.
Image: X-ray of a hip osteoarthritis from iStock