Osteoma of the long bones and the spine. A study of eleven patients and a review of the literature.

The clinical features, radiographic and histopathological findings, treatment, and results are described for eleven patients who were managed for an extracranial osteoma at our medical center between 1980 and 1993. Ten of the patients were initially seen because of dull, aching bone pain that had been present for two weeks to thirty years. Radiographs demonstrated single or multiple homogeneous, well defined, radiodense foci with smooth round or lobulated margins. The histopathological features consistently included uniformly dense, compact, cortical-like, mature lamellar bone. The preoperative diagnosis was unclear for all patients, and osteoma was rarely considered in the differential diagnosis. For four patients, a tentative diagnosis of osteosarcoma was made, and a wide excision was carried out in two of these patients. Marginal excision with less than three millimeters of normal tissue around the lesion was performed in most patients. None of the osteomas recurred, and ten patients had relief of the pain. Awareness of the clinical, radiographic, and histopathological features of osteoma, as described, is valuable for making a differential diagnosis and for distinguishing osteomas from other lesions.

Hyponatremia and syndrome of inappropriate antidiuretic hormone secretion in adult spinal surgery.

STUDY DESIGN: Patients undergoing spinal surgery were monitored for sodium balance, fluid type, and volume input and output during surgery and for the first 3 postoperative days. OBJECTIVE: To prospectively document the true incidence of the syndrome of inappropriate antidiuretic hormone secretion and hyponatremia, and identify risk and protective factors for the development of the syndrome of inappropriate antidiuretic hormone secretion after spinal surgery. METHODS: Data on medical history, surgical procedure, estimated blood loss, and volumes and types of intraoperative and postoperative fluids were collected on 116 consecutive spinal surgery patients during March to July 1992. RESULTS: One hundred one spinal operations in 96 patients were evaluated. There were 48 males and 48 females, with a mean age of 52 years (range, 16 to 90 years). Hyponatremia developed in 45 (44.6%) patients. The etiology of hyponatremia was the syndrome of inappropriate antidiuretic hormone secretion in seven patients (6.9%), hypovolemia in 19 patients (18%), and other causes in six patients. CONCLUSIONS: Spine patients are at risk for hyponatremia and the syndrome of inappropriate antidiuretic hormone secretion. The incidence of the syndrome of inappropriate antidiuretic hormone secretion was 6.9%. Serum sodium should be monitored postoperatively. Patients who undergo a revision operation have an approximately two to four times greater risk of being affected by the syndrome of inappropriate antidiuretic hormone secretion than those who have primary surgery.