May 8, 1981

Osteonecrosis vs Transient Osteoporosis

Author Affiliations

Rutgers Medical School Piscataway, NJ

JAMA. 1981;245(18):1817. doi:10.1001/jama.1981.03310430011002

To the Editor.—  Regarding the recent case report of osteonecrosis of the femoral head during pregnancy (1980;244:689), we have had recent experience with a pregnant woman of strikingly similar clinical course and laboratory findings in whom we favored the diagnosis of transient osteoporosis of the hip (TOH) over that of osteonecrosis.Although most typically an affliction of middle-aged men, there have been at least nine cases reported of the rare entity of TOH in which pregnancy was the only implicated pathogenic factor.1-3 The clinical signs of rapidly developing pain in the hip girdle, aggravated by weight bearing, and associated with Trendelenburg's gait are identical to those of osteonecrosis. Roentgenograms in TOH show homogeneous or mottled osteoporosis, not unlike those changes of early osteonecrosis, but fail to show progression to trabecular fracture and osteosclerosis.Radionuclide bone scanning in TOH shows greatly increased uptake centered in the epiphyseal area and