Steroid injections are commonly used to treat pain and inflammation in a joint, such as the hip, knee or shoulder, but new research has identified bone changes in patients who received a steroid injection in the hip.
In a study presented at the annual meeting of the Radiological Society of North America (RSNA), osteoarthritis patients who received a hip steroid injection had a significantly greater incidence of bone death and collapse compared to two control groups.
“Changes due to osteoarthritis, such as narrowing in the space between joints and the development of bony proliferations, typically develop slowly over time,” said Dr Connie Y. Chang, radiologist at Massachusetts General Hospital and assistant professor of radiology at Harvard Medical School in Boston. “When reading follow-up radiographs of patients who had received a hip injection, we noticed changes had developed rapidly in some patients.”
Dr Chang and a team of radiologists specialising in musculoskeletal diagnostic imaging and intervention, including hip injections, conducted a study involving 102 patients in order to find out whether their arthritis worsened following a hip steroid/anaesthetic injection.
Study participants had X-ray images taken of the treated hip at the time of the injection and during a follow-up appointment three to nine months later.
Two musculoskeletal radiologists independently reviewed these images and those of two control groups — 102 matched patients who had hip X-rays without steroid/anaesthetic injection and 44 patients who underwent imaging and a steroid/anaesthetic injection in the shoulder.
According to the RSNA, the radiologists reported new osteonecrosis in 22-24% of hip injection patients, compared to 5-9% in the hip control group and 5% in the shoulder injection control group. They observed bone collapse in 15-17% of hip injection patients, versus 4% of hip control patients and 2% of shoulder control patients.
Hip injection patients also showed increased imaging findings of osteoarthritis compared to the control groups, but these differences were not statistically significant.
Dr Chang noted that patients receiving hip injections have symptoms of hip pain severe enough to require the injection, which means they may be prone to faster progression of bony changes compared to the control groups. These considerations may be important as some specialists are requesting higher steroid doses and injections in younger patients, she explained.
“We need to look at what’s going on with the steroid/anaesthetic injectate and osteoarthritis patients to determine what’s causing the changes that occur in some patients,” Dr Chang said. “However, we don’t want to deter patients from getting an injection. These results are enough to warrant an investigation, but not enough to cancel a procedure.”