Investigation performed at the Bioengineering Laboratory, Department of Orthopaedic Surgery, Louisiana State University Health Sciences Center, New Orleans, LouisianaDepartment of Orthopaedic Surgery, Louisiana State University Health Sciences Center, 2025 Gravier Street, Suite 400, New Orleans, LA 70112. E-mail address for R.V. Baratta: rbarat@lsuhsc.edu (Edwards, Greene, Baratta, Willis)Department of Pathology, Louisiana State University Health Sciences Center, 1901 Perdido Street, New Orleans, LA 70112 (Zieske)