The Effectiveness of a Three Phase Bone Scan for Making the Diagnosis of Complex Regional Pain Syndrome

ABSTRACT

BACKGROUND: Complex regional pain syndrome (CRPS) is still difficult to diagnose in the field of chronic pain management. CRPS is diagnosed by purely clinical criteria based on the characteristic signs and symptoms, which have to be differentiated from similar pain conditions like posttraumatic neuropathic pain. Until now, there has been a lack of objective diagnostic tools to confirm the diagnosis of CRPS. The aim of this study was to evaluate the usefulness of a three phase bone scan (TBS) for making the diagnosis of CRPS. METHODS: A total of 121 patients who had been diagnosed with CRPS were evaluated. All the patients were examined by performing a TBS as a part of the diagnostic work-up. A diffuse increased tracer uptake on the delayed image (phase III) was defined as a positive finding for CRPS. RESULTS: Forty-one patients (33.9%) out of 121 showed the positive results on the TBS. The patients with a duration of pain of less than 24 months had a significantly higher positive result (43.4%) on the TBS than did the patients with duration of pain longer than 24 months (12.1%). CONCLUSIONS: A TBS could give a better objective result for diagnosing CRPS for patients with a shorter duration of pain and a TBS gives little information for the diagnosis of CRPS in patients with a duration of pain longer than 24 months.