The Journal of Bone and Joint Surgery

Image Quiz

Pain in the Lateral Malleolus Fifty-two Months Following Open Reduction and Internal Fixation of an Ankle Fracture¹ (continued)

Answer: Late foreign-body reaction to an interosseous bioabsorbable polylactic acid screw

For larger view, click on image

Fig. 3

At the time of exploration, in October 1995, a 1-cm-diameter granulomatous lesion that was composed of relatively firm connective tissue was found at the entrance hole of the screw track; the lesion was partly extraosseous and partly intraosseous. The lesion was excised, and the bone was curetted. No remnants of the implant could be seen macroscopically, but histological examination revealed an abundance of polymeric particles that were birefringent under polarized light (Fig. 3). Particles that were smaller than 4 μm in diameter were located within the cytoplasm of mononuclear macrophages. Larger particles were surrounded by multinucleated foreign-body giant cells. The largest polymeric particles, 30 to 40 μm in diameter, were found in the extracellular space with few surrounding reactive cells. The cell population was composed mainly of macrophages. Lymphocytes comprised approximately 10% of all identifiable cells. Immunohistochemical analysis showed the lymphocytes to be CD3-positive and L26-negative; this antigenic marker pattern is typical of T-lymphocytes. The overall histological picture was indicative of a nonspecific foreign-body reaction. There was no evidence of an infection or a malignant lesion.

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