No abstract

No abstract

Heterotopic ossification is characterized by formation of normal bone in abnormal locations. It usually occurs in the muscle, after neurologic injury, burns or orthopedic surgery and sometimes occurs in abdominal wound incisions and scars. It is quiet rare to see heterotopic bone formation in the mesentery. Only 19 cases have been reported in the English literature. We report the 20th case of a 37-year-old man who presented with small bowel obstruction after surgery for appendicitis. During the surgery for small bowel obstruction, he was noted to have severe inflammation and fibrosis of the mesentery. Histologic examination revealed islands of mature bone formation in the mesentery. He had a protracted course in the hospital but ultimately recovered. We also summarize the existing reports in the English literature on this rare condition, which is difficult to diagnose preoperatively and is associated with considerable morbidity and mortality. (The Endocrinologist 2006;16: 323-328) Learning Objectives • Summarize what is known about heterotopic ossification in general and heterotopic mesenteric ossification (HMO) in particular. • Outline the salient features of 20 reported patients having HMO (including the present patient), emphasizing patient characteristics, presenting findings, relationship to previous abdominal surgery, growth rate, and appropriate treatment. • List possible factors that may cause or contribute to the development of HMO.H eterotopic ossification (HO), the formation of normal bone in abnormal locations, occurs in congenital/genetic disorders such as fibrodysplasia ossificans progressiva (FOP), 1 Albright hereditary osteodystrophy, 2 and progressive osseous heteroplasia. 3 HO may also be seen after neurologic injury, burns, muscle injury, or orthopedic surgery, especially total hip arthroplasty 4 as well as in some tumors. 5,6 HO in abdominal wound incisions and scars 7,8 has been reported, predominantly in men. The mechanism of HO is unknown. One theory suggests that injury and inflammation are followed by the transformation of undifferentiated mesenchymal cells into bone cells. 4 We report a patient who developed HO of the mesentery after abdominal surgery. His condition was further complicated by prolonged small bowel obstruction (SBO), abscess formation, and fistula formation. We summarize existing reports of this rare condition from the English literature. CASE REPORTA 37-year-old man was hospitalized with abdominal pain and suspected acute appendicitis for which he underwent laparotomy and appendectomy. The initial postoperative course was uneventful and he was discharged 3 days after surgery. He was readmitted 7 days later with symptoms of SBO and underwent reexploration the next day. A severe inflammatory process involving the mesentery, loops of the small bowel, and the abdominal wall was noted during the surgery. Dissection of loops of bowel to unravel the firm adherence caused multiple tears of the serosa necessitating