• Explain to interested patients that this study did not include a control group, limiting the ability to assess the benefit of using ultrasound to guide cortisone injections.

Using ultrasound to guide cortisone injections may be an effective treatment for lateral hip pain resulting from gluteus medius tendinopathy, a small, uncontrolled study found.

Of 54 patients who received the treatment, 72% had a clinically significant reduction in pain one month later, and 70% were at least somewhat satisfied with the results, according to Étienne Cardinal, MD, of the University of Montreal Hospital Center, and colleagues.

There were no complications, they reported in the January issue of the American Journal of Roentgenology.

“Our study shows that a peritendinous ultrasound-guided corticosteroid injection may be an effective treatment of gluteus medius tendinopathy,” they wrote.

Although they recognized the need for randomized controlled trials to confirm a benefit, they wrote that “in a routine clinical setting, a specific indication for ultrasound-guided injection might be for the treatment of patients who did not respond initially to a blinded cortisone injection.”

But experts not involved in the study were skeptical of the need for ultrasound.

“This is an entirely unnecessary and expensive technique,” said Mark Brown, MD, PhD, of the University of Miami in Florida, adding that a control group receiving injections without an ultrasound guide would have had the same results.

“This is another example of expensive technology that adds nothing to the treatment of the patient being introduced without adequate evidence-based medicine,” he wrote in an e-mail.

Andrew Haig, MD, of the University of Michigan in Ann Arbor, wrote in an e-mail, “It seems absurd to add the expense and hassle of ultrasound when simply injecting the trochanter blindly has great results too.”

Mehul Desai, MD, MPH, of the George Washington University Hospital in Washington, remained open to the possibility that ultrasound added benefit.

“This procedure may allow us to diagnose issues of gluteus medius tendinopathy more accurately, and subsequently allow more targeted injections with the lowest possible amount of medications,” he said, “but that is not clear based on this study.”

The 54 patients (mean age 54.7) included in the study all had a diagnosis of gluteus medius tendinopathy with a history of trochanteric pain lasting at least six weeks.

Conservative treatment, including analgesis, nonsteroidal anti-inflammatory drugs, and physiotherapy, had failed.

After undergoing a baseline pain assessment, each patient received a gluteus medius peritendinous injection of 30 mg of triamcinolone combined with 3 mL of bupivacaine 0.5% with continuous ultrasound monitoring.

One month after treatment, pain on a 10-cm visual analog scale was reduced 55% from baseline — from 6.4 to 2.9 (P<0.001).

Nearly three-quarters (72%) had a reduction of at least 30%, deemed to be clinically significant.

On a 4-point rating scale, 70% of the patients reported being somewhat or very satisfied with the results.

Outcomes did not differ between patients with and without signs of bursopathy.

The study was limited, the researchers wrote, because the technique is dependent on the experience and skill of the sonographer and because there is no reference standard for the diagnosis of gluteus medius tendinopathy.