Influence of low grade exercise on skeletal scintigraphy using Tc-99m methylene diphosphonate

Tc-99m methylene diphosphonate [MDP] bone scan is the basis of the skeletal imaging in nuclear medicine being a highly sensitive tool for detecting bone diseases. Mechanical stimulation induced by low grade exercise or whole-body vibration appears to be advantageous regarding the maintenance and/or improvement of skeletal mass in humans. We aimed to assess the physiological influence of low grade exercise on the quality of skeletal scintigraphy using Tc-99m MDP.

Tc-99m MDP bone scan was done for 92 volunteers [Group 1; G1]. Five days later, the same subjects were re-scanned [Group 2; G2] after an exercise on treadmill for 5 minutes. Image quality was assessed using quantitative measures whereby equal regions of interest (ROI) were drawn over the femoral diaphysis, and the contralateral adductor area. The total number of counts from the bone [B] ROI and soft tissue [ST] ROI was expressed as a ratio [B:ST ratio] and a mean value for each was established.

Statistically significant difference was found between the B:ST ratio means [p = 0.001] in G1 and G2.

This study raised a physiological influence of low grade exercise on the image quality of tc-99m MDP skeletal scintigraphy by increasing MDP osseous uptake.