Fig 1.
Two-dimensional angiography of the piglet hip pre- and post-embolization.
(A) Normal vascular anatomy of the porcine hip, Piglet 1. (B) Sub-selection of the DMFCA demonstrating ascending flow of a contrast agent toward the femoral head, Piglet 4. (C) Absence of perfusion within the DMFCA following its embolization after injection of a contrast agent into the deep femoral artery, Piglet 4. (D) Enhancement of the femoral head after sub-selection of the AMFCA prior to embolization, Piglet 8. (E) Absence of femoral head perfusion after sub-selective injection of a contrast agent into the embolized AMFCA, Piglet 8. Femoral head (*); femoral head and femur (dotted red line); DMFCA (white arrowheads); AMFCA (blue arrows).
Fig 2.
Histologically defined regions of interest.
Four distinct patterns were present in the examined sections, including (A) normal marrow and bone, (B) reduced cellularity of marrow without other changes, (C) fibrovascular repair tissue, and (D) necrosis of marrow and/or bone without evidence of repair. H&E, scale bars = 100 µm.
Fig 3.
Three-dimensional reconstruction of hip vascular anatomy.
(A), (B), and (C) depict the lateral, anterior (cranial), and medial aspects of the hip joint and its vasculature, respectively in a 6-week-old piglet on CT angiography with intra-arterial contrast injection. Femoral head (*); greater trochanter (GT); femoral neck (FN); DMFCA (white arrowheads); AMFCA (blue arrows).
Fig 4.
CE-MRI and histology of the hip joints following bilateral embolization of the DMFCA alone in Piglet 1.
Subtracted CE-MRI of T1-weighted TSE images acquired either (A) immediately after post-embolization, or (B) 7-days post embolization. Regions of ischemia appear black (*) and regions with perfusion appear either gray or white (arrow). Corresponding histology at 0.5 of the (C) right and (D) left hip obtained after euthanasia at 7-days postoperatively. Areas of fibrovascular repair (black dotted line); areas of necrosis (green line). Scale bars = 5 mm.
Table 1.
Embolization procedures and associated femoral head ischemia.
Fig 5.
CE-MRI and histology of the right hip following embolization of both the DMFCA and AMFCA in Piglet 8.
(A) Subtracted CE-MRI of T1-weighted TSE images acquired 7-days post embolization. (B) Corresponding H&E-stained histology at 0.5. Secondary center of ossification of the femoral head (yellow line); regions of increased signal on CE-MRI that correspond to regions of fibrovascular repair on histology (dotted line); regions of ischemia on CE-MRI that correspond to acute necrosis without repair on histology (green lines); histologically normal regions of the femoral head (++). Scale bar = 5 mm.
Table 2.
Pathologic changes present and regions affected after induction of femoral head ischemia.