At least every month I encounter a new patient for a second opinion about their planned Morton.s neuroma surgery. Many of these patients state they failed to get sigificant releif from a steroid injection on at least one attempt. I am usually suspicious that either the diagnosis is incorrect or that the injection was done blind (without the use of ultrasound images to guide the injection around the neuroma).
Most of the second opinions that I see did not have the benefit of ultrasound guided injection. Of course, before I recommend a more permanant solution to the problem (decompression vs removal vs ablation) I do recommend to try at least one ulrasound guided injection to the neuroma.
There are two reasons why I recommend this treatment. First, I perform a detailed scan of the anatomy be sure that a Morton"s neuroma exists, and to evaluate the other structures in the area for pathology. Second, performing the injection with the direct visualization of the nerve allows the injection to be as close to the nerve as possible without traumatizing the nerve.
Usually, an injection of steroid to a Morton's Neuroma under direct visualization with ultrasound will be more effective than a blind injection. Furthermore, many of these patients had significant and long lasting pain releif.
For a more scientic discussion...
A systematic review of ultrasound-guided and non-ultrasound-guided therapeutic injections to treat Morton's neuroma. Peter Morgan, Wendy Monaghan, Simon Richards. JAPMA 2014 Jul;104(4):337-48.