PA and lateral views.

(3) How would you work up her pain?

Differential lidocaine injections would be my first choice, although I think that many different approaches may work well, too.

I like the differential lidocaine injections because they are quite specific (as to site) and reliable, quick, low-cost, and can be done at the time the problem first comes to light. The downside is that the test is site specific, not etiology specific. Just because the source of the pain is, for example, the radiocarpal joint, does nto tell you what within the radiocarpal joint is the cause.

The term "differential" comes from the fact that one can differentiate between several possible sites of pain. If there are two possible sites as the sources of pain, I will usually inject the site I think is NOT the source, to rule it out, and then inject the site that I think is the more likely source. The key is not the order of the injections, it is thinking of the technique and employing it.

One could also order a CT scan, but the downsides are the cost, time delay, and lack of specificity: one cannot assume that a CT abnormality is necessarily the source of pain. It is quite useful, however, in conjunction with the differential lidocaine test, if it has indicated that one specific site is the source of the pain.

The patient's pain did not resolve by five months after surgery. She was given a lidocaine/cortisone injection to the midcarpal joint 10/10/06, without relief. Next, she had a lidocarine/cortisone injection to the DRUJ on 10/31/2006, without relief. Finally, she had lidocaine/cortisone to 4th dorsal compartment on 11/18/06 with pain relief.

(4) What would be your next step? Do you need further workup, or would you proceed with treatment of her pain?

(5) What do you think is the most likely diagnosis?

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