Intermittent pneumatic soft tissue compression: Changes in periosteal and medullary canal blood flow.

We previously demonstrated that the use of intermittent pneumatic soft tissue compression (IPC) treatment enhanced fracture healing in an animal model, but the exact mechanism remained unknown. The purpose of this study was to determine the local and remote effects of IPC treatment on blood flow within the medullary canal and outside the periosteum of mid-tibial diaphysis. Blood flow was measured with a Laser Doppler blood flow meter in the lower limbs of 21 rabbits. Laser probes were inserted at three different sites of the mid-diaphysis on the right tibia: in the medullary canal (n = 21), outside the periosteum on the lateral side (n = 11), and outside the periosteum on the medial side (n = 10). IPC was applied for 30 min through cuffs that were placed around the feet and the lower part of the calf. While applying IPC to the left leg, no changes in blood flow occurred on the right leg (remote changes). However, while applying IPC to the right leg, significant localized changes were found on the right leg, including 47 and 89% increases in total amount of blood flow outside the lateral and medial periosteum, respectively. Although an altered blood flow pattern was observed in the medullary canal, no significant change in total amount of blood flow was observed at this level. In summary, the present study demonstrated that the use of IPC in an intact bone model results in a significant local increase in total blood flow, with minimal measurable effects on the contralateral limb.