Hemiosteoporosis Following Stroke: Importance of Pathophysiologic Understanding and Histologic Evidence

To the Editor: We read with interest the article by Ramnemark et al1 reporting that patients developed hemiosteoporosis during the first year after severe stroke. These authors concluded that hemiosteoporosis occurred independently of any weight change after stroke. Other reports have indicated that bone mass or bone mineral density (BMD) is reduced in stroke patients on the hemiplegic side, reflecting both degree of paralysis and vitamin D deficiency.2 3 4 In these investigations, bone changes were determined by bone mass or BMD with x-ray radiodensitometry2 3 or dual-energy x-ray absorptiometry,4 without histologic assessment. However, the diagnosis of osteoporosis requires histological demonstration that both bone matrix and bone mineral area are lost. Ramnemark’s report1 does not mention quantitative assessment of bone biopsy specimens. To our knowledge, histologically proved osteoporosis in patients after stroke has not been reported, although a well-established relationship exists between prolonged immobilization and osteoporosis in spinal cord injury.5 Our previous findings3 have shown lower …