The use of ultrasound to guide knee injections for osteoarthritis treatment led to a 42 percent reduction in pain, a doubled response rate to therapy and a 15 percent reduction in cost to patients, compared with conventional palpation-guided injections, according to a study that will be presented Nov. 11 at the Annual Scientific Meeting of the American College of Rheumatology in Atlanta.
Palpation-guided intraarticular knee injection is the conventional treatment to remove joint fluid and administer medication for patients with osteoarthritis (OA), which is the most common joint disease among middle-aged and geriatric patients. The researchers set out to measure the effects of performing the same procedure with the use of ultrasound guidance.
Ninety-four knees were randomly selected for treatment with 80 mg of triamcinolone using either palpation-guided anatomic injection or ultrasound-guided injection. Both procedures involved the drainage of fluid from the joint followed by the injection of the corticosteroid using the same needle. In the ultrasound cases, researchers were able to confirm needle placement and the administration of triamcinolone in real-time.
Patients administered the treatment with ultrasound-guidance reported a 48 percent reduction in pain during the procedure and an average of a 42 percent reduction at 2-week and 6-month followups, compared with patients who underwent the palpation-guided treatment. Ultrasound-guidance also resulted in a 107 percent increased response-rate to the treatment and a reduction in non-responsiveness of 52 percent relative to the control group.
The duration of relief after the procedure was extended by 36 percent in the ultrasound group, with all results reported as statistically significant.
"The study demonstrates that when physicians use ultrasound and a technique called hydrodissection performed with precise new mechanical syringes to inject the joint, the patient experiences less pain, improved safety, a better response to medications, and less need for other medical therapy," according to one of the researchers, Wilmer Sibbitt, Jr., MD, professor of rheumatology and neurology at the University of New Mexico Health Sciences Center in Albuquerque.
The study also found that the cost of the ultrasound-guided procedure was 15 percent lower (a $48 reduction) over the course of an average year's treatment. This drop resulted in a 59 percent savings, or $593 per year, for the average patient who responded to treatment.
"Rheumatologists are increasingly using ultrasound, and patients should be aware that joint injections may be more effective and less painful if their physician offers this option to them," Sibbitt reasoned.