Infiltration of the coccyx region can be useful as a therapeutic procedure in coccydynia after exclusion of infection or other significant pathology.
After informed consent is obtained, the patient is positioned in the lateral Sims’ position with the left side down for right-handed clinicians. With the upper leg flexed, the buttocks are separated, allowing easy access to the sacrococcygeal junction. The patient is prepared in a standard aseptic fashion over an area large enough to allow palpation of landmarks, and sterile technique is used throughout the procedure. The area of tenderness is localized by palpating from the tip of the coccyx to the sacrococcygeal junction. The palpating hand is kept in position, and a 1½-in. (4-cm), 21-gauge needle is inserted at the point of maximal tenderness perpendicular to the skin. After negative aspiration, a 3-mL mixture of 20 mg of methylprednisolone acetate or equivalent and local anesthetic is injected into the tender area using a fan pattern (Fig. 67-49).
FIGURE 67-49. Coccygeal junction injection. Approach for coccygeal junction injection.
It is not necessary to advance the needle into the sacrococcygeal junction. Infiltration of the superficial tissue at the point of maximal tenderness is usually adequate.
Perianal numbness may be noted for 24 hours after injection. Serious complications are uncommon with appropriate needle placement.