Triphasic Bone Scintigraphy Is Not Useful in Diagnosis and May Delay Surgical Treatment of CRPS of the Hand.

Background: Triphasic bone scintigraphy (TPBS) is often used to diagnose complex regional pain syndrome (CRPS). The primary aim of this study is to determine if the diagnosis of CRPS in patients with a positive TPBS (TPBS +ve) is accurate. A secondary aim is to determine if there was delay in treatment of patients who underwent TPBS compared to those who did not have a TPBS. Methods: Of 225 consecutive patients presenting to the first author's practice with a diagnosis of CRPS, 65 had TPBS performed before referral with 62 having TPBS +ve. The remaining 160 were clinically diagnosed and a TPBS was not done (TPBS-ND). Patients were classified into five categories - wrong diagnosis, dystonic-psychogenic hand, causalgia, flare reaction and irritative carpal tunnel syndrome (ICTS). Patients with flare reaction and ICTS were considered as having true CRPS and the rest were considered as misdiagnosis. The patients' demographics, duration of symptoms, pre- and postoperative pain, functional score and patient satisfaction were compared. Results: Of the 62 TPBS +ve, there were 38 (61%) misdiagnosis. The proportion of misdiagnoses was fewer in the TPBS-ND group (45%; p = 0.036). Thirty-two of the 62 TPBS group (52%) and 92/160 (56%) of the TPBS-ND group had surgical treatment. At a mean follow-up of 19 months, pain dropped 6.5 ± 2.5 points in the TPBS +ve group. Disabilities of the arm, shoulder and hand (DASH) score fell by 56 ± 27. The mean single assessment numeric evaluation (SANE) score was 8.6 ± 2.3. These results did not differ substantially from those of the TPBS-ND group. Conclusions: A significant number of patients in this study who had TPBS +ve were misdiagnosed in this study. Outcomes after treatment of CRPS were consistently good despite the results of the TPBS. Patients with TPBS +ve had a significant delay to diagnosis. We conclude that TPBS is not useful in the management of CRPS. Level of Evidence: Level III (Therapeutic).