After 1 Year, Ultrasound-Guided Corticosteroid Injections Are Superior to Hyaluronic Acid Injections to Relieve Pain of Morton Neuroma

CLINICAL QUESTION

Are ultrasound-guided corticosteroid injections superior to hyaluronic acid injections for pain relief in patients with Morton neuroma?

BOTTOM LINE

In this small, unmasked randomized trial, patients who received ultrasound-guided corticosteroid injections experienced significantly greater pain reduction (but also experienced skin discoloration) than those who received hyaluronic acid injections. Because pain was the primary outcome, the lack of a placebo group is a serious omission. (Level of Evidence = 2b)

SYNOPSIS

The researchers recruited patients older than 16 years from a clinic in São Paulo, Brazil, who had Morton neuroma (confirmed by ultrasonography or magnetic resonance imaging) and whose pain exceeded a 3 out of 10 on a visual analog scale. They were randomized to receive three weekly injections of hyaluronic acid (40 mg/2 mL; n = 22 patients, 24 feet) or triamcinolone hexacetonide (40 mg/2 mL; n = 22 patients, 24 feet). The researchers evaluated the patients 1 month after injections and then again at 3, 6, and 12 months. During each follow-up interval, patients in both groups experienced clinically meaningful pain improvement, but the degree of improvement was greater in those treated with triamcinolone hexacetonide (1.7–3.4 [all are clinically meaningful pain differences]). The authors report similar improvement as measured by the American Orthopaedic Foot and Ankle Society score (a composite of pain, function, and alignment). The authors also report that skin discoloration occurred in six of the patients (six feet, 25%) who received triamcinolone hexacetonide injections but not in those treated with hyaluronic acid. Finally, none of the patients underwent surgery during the follow-up interval.