Figure 2

(left) Illustration of tibial defect filled with a 5 cm intercalary allograft and stabilized with a static, interlocking IM nail; these junctions were stimulated daily with LIPUS and/or modified with LAP; proximal (right) and distal (not shown) host graft junctions containing 2 cm of host bone and 2.5 cm of allograft were transected in the sagittal plane allowing for quantification of mineral apposition rate (MAR) in the cranial and caudal cortices as well as the interface regions; regions of interest (ROIs) evaluated were designated as periosteal, middle, and endosteal in the graft, host, and interface from which global averages were derived (animal treated as experimental unit); up to 10 fluorescent images were taken to evaluate MAR in the cranial and caudal callus regions.