Clinical Tips on Joint Aspiration and Injection
Doctors face daily challenges in the treatment of a wide range of medical conditions. Helpful hints and clinical tips on specific procedures are useful for the management of some patients.

In this article, the focus is on aspiration (drawing fluid out) and injection of the first metatarsophalangeal (MTP) joint. Patients with gout may need this procedure. The MTP joint is also known as the big toe or great toe. This joint is discussed because getting a needle into the area can be difficult.

When swelling is present, it can be a problem to recognize guiding points on the surface anatomy. There may be bone spurs along the joint line making access impossible. And the surgeon must avoid puncturing nerves, blood vessels, and tendons in the same area.

To help physicians navigate this procedure, supplies needed are listed. Then a review of surface anatomy along with patient and joint position are offered. A photo of the traction used to pull the joint space open is included. This information will help the physician find the right space between the joints in which to insert the needle.

The correct needle angle is important to avoid the bone and locate the pocket of fluid. It may be necessary to use the anatomy of the unaffected foot and toe as a model of what is normal. Comparing the healthy side to the swollen, involved toe can help guide the physician.

Specific techniques for preventing leakage of corticosteroids injected into the joint and spritzing the aspirant are included. Spritzing fluid taken from the joint is a way to spray a few drops onto a slide. The slide can then be analyzed under a microscope.

This article was the fifth in a special series on joint aspiration and injection. Previous reports have included basic information on this topic as well as techniques for specific sites. So far the elbow joint, elbow bursa, and shoulder joints have been discussed. Watch here for review of future topics on this subject.
References
Evan Bilstrom, MD, et al. Aspiration and Injection of the Metatarsophalangeal Joints. In The Journal of Musculoskeletal Medicine. December 2007. Vol. 24. No. 12. Pp. 517-518.