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Commentary

This is a thorough review of bone graft expander agents

used in augmenting autografts in performing lumbar

fusions. Will genetically engineered bone morphogenic

protein agents make such information obsolete? Perhaps

not—given the economic factors associated with the use of

the newer products.

Howard Morgan, MD

Department of Neurosurgery

University of Texas Southwestern Medical Center

Dallas, TX 75390, USA

N.E. Epstein / Surgical Neurology 69 (2008) 16–19 19