Complex regional pain syndrome of the lower extremity: a retrospective study of 33 patients.

Even when diagnosed early and treated appropriately, patients with complex regional pain syndrome (CRPS), a condition that can lead to severe painful dysfunction of the limb, may continue to have long-term pain. A retrospective study was conducted of 33 patients with a positive history of CRPS I, CRPS II, or sympathetically maintained pain (SMP) of the lower limb who were treated in either a clinical setting or a pain management center. The average age of individuals diagnosed with CRPS was 43.5 +/- 12.6 (mean +/-SD) years with 60% being female. The most common diagnosis was CRPS I (75.8%) followed by SMP (21.2%), and finally CRPS II (3.0%). The dominant etiology was confirmed as trauma (73%), with the remaining nine cases resulting from elective foot surgery. Fractures were the most common type of injury (45%) and excision of neuroma was the most frequent elective surgical procedure (30%). Time from injury to diagnosis in patients with foot and ankle trauma was 3.9 +/- 3.0 months and from elective surgery to diagnosis was 9.1 +/- 4.0 months (t test, p < .001). Thirteen patients were contacted for long-term follow-up with an average of 3.5 years after initial diagnosis. There was no difference when the pain rating at long-term follow-up was compared to the initial rating (6.2 +/- 1.2 vs. 7.3 +/- 0.6; p = .287), and 11 continue to have more than moderate pain. Thus, many patients with CRPS who seem to be successfully treated, and are discharged from care, still have severe pain years later.