SUN-541 Complex Regional Pain Syndrome: Our Experience from 60 Cases

Complex Regional Pain Syndrome (CRPS) or Sudeck Disease is a chronic painful disease that usually affects an extremity and is accompanied by sensory, motor, autonomic, skin and bone abnormalities. AIMS: -Describe demographic characteristics, triggers and clinical manifestations in 60 patients diagnosed with CRPS -Describe diagnostic methods, treatments performed and clinical results obtained MATERIAL AND METHODS: Retrospective review of digital clinical records of 60 outpatients diagnosed with CRPS who were assisted in our bone clinic between June 2013 and September 2017. RESULTS: Median age was 55.3 ± 13 years (24 - 85 years), 76.6% were female. Surprisingly, 38% of the patients were health professionals. Half of them were referred by other specialists, mostly orthopaedists. Trauma with fracture was the most frequent triggering factor (65%). The second one was lower limb surgeries, predominantly Hallux Valgus. Lower limbs were the most affected (90%), especially feet (70%). Predominant signs and symptoms were pain (83%) and edema (58%). Average vitamin D value was 22.9 ng/dl. Most RX (67%) described typical findings (osteoporotic changes, erosions and a ground glass appearance). Three-phase bone scintigraphy with Tc99 showed a typical increased uptake pattern compatible with CPRS (90%). MRI showed edema and bone involvement in 80% of cases. DXA was performed in 26 patients. Mineral density and bone mineral content values were obtained from the affected limb and its contralateral healthy one, using a special ROI manually positioned. Values of the affected side were compared to the healthy contralateral limb and were significantly lower (between -13% and -16%). After bisphosphonate treatment, DXA scan was performed in 10 patients evidencing improvement and reduction of the difference between both limbs in all patients. Fifty patients were treated with bisphosphonates: IV 3mg ibandronate (22), IV 5 mg zoledronate (15), IV pamidronate (180 mg divided in 3 doses) (12) and oral alendronate (1). Clinical improvement was reported in 100% of patients treated with pamidonate, 94% with ibandronate and 76% with zoledronic acid. This last treatment showed a quicker effect and the recovery time was shorter. Only 14% reported flu-like syndrome as adverse event. CONCLUSIONS: As described in the literature, CRPS patients are relatively young (55 years), mostly women and fracture is the most common triggering factor. Involvement of the lower limbs was much more frequent in our cohort. DXA showed to be a good tool that allows quantification of BMD difference between both limbs and improvement after treatment. IV Bisphosphonates were the main treatment our patients received with excellent results and few adverse effects.