Inflammatory reaction to implanted equine pericardium xenograft.

Equine pericardium xenograft is now widely used to augment Achilles tendon repair. In this article, we describe the case of a postoperative complication in a healthy 37-year-old male who underwent primary repair, augmented with equine pericardium, of his acutely ruptured Achilles tendon. At 4 months postoperative, an indurated and fluctuant subcutaneous soft tissue reaction was noted at the repair site. Further questioning led the patient to recall having an allergy to horses, although it had been a very long time since he had experienced any symptoms related to the allergy and, as such, he failed to mention this important fact at the time of his initial examination. At 11 months postoperative, the xenograft was removed and, thereafter, the wound healed uneventfully. At 6 months following removal of the xenograft, the patient displayed no evidence of allergy or Achilles tendon dysfunction.