Technetium-99m sestamibi limb scintigraphy in post-traumatic reflex sympathetic dystrophy: preliminary results

Reflex sympathetic dystrophy (RSD) has widely variable clinical manifestations. Its pathogenesis remains partially unexplained. RSD is commonly divided into three stages; these stages are not always clearly separable, but staging remains important for correct treatment. Since the disease involves soft tissue alterations as well as bone changes, we decided to investigate whether technetium-99m sestamibi limb imaging can be used to evaluate the soft tissue appearance. Fifteen patients (seven females and eight males; age range 12-68 years) with clinically significant post-fracture RSD were evaluated with both three-phase bone scan (TPBS) and 99mTc-sestamibi limb scintigraphy. Although, in general, patients with similar duration of disease, clinical stage and TPBS activity tended to have similar patterns of sestamibi uptake, discordant uptake patterns were observed in some patients with clinical stage 1. Thus, of 12 patients with stage I disease, eight had increased 99mTc-sestamibi activity in the distal part of the affected limb, while three had normal activity and one had decreased activity. All three patients with stage II disease showed normal 99mTc-sestamibi uptake. Although most of the patients with increased 99mTc-sestamibi uptake had increased activity on all three phases of the bone scan, there were discordant results between the scan patterns in other patients. On the basis of these findings, we suggest that 99mTc-sestamibi imaging may contribute to the differentiation between clinical stages and may permit evaluation of the disease course and selection of appropriate therapy. 99mTc-sestamibi imaging is not, however, a primary diagnostic procedure for RSD.