[Reflex sympathetic dystrophy secondary to lumbar disk herniation].

A 26-year-old woman noticed discoloration and swelling of the left foot after standing or sitting for a long period of time. Four months later, she developed dysesthesia in the left leg and foot and extreme tenderness of the left foot; developed subsequently claudication. At age 15, the patient had severe low back pain for 1 year and had been diagnosed as having lumbar disk herniation. Recurrent disk herniation was suspected, although myelogram and postmyelogram CT scan reportedly were nondiagnostic. The patient was admitted to our hospital 6 months following the onset of dysesthesia. Physical examination revealed weakness and atrophy of the entire left lower extremity, allodynia of the left foot, and dysesthesia in the left L5 myotomes. Hypertrichosis was obvious, and the left foot was cool on touch. Roentgenography of the left lower extremity revealed patchy osteoporosis of the distal epiphyse of the left tibia and fibula and in some of tarsal bones. Intravenous administration of phentolamine reduced tenderness, which was highly suggestive of reflex sympathetic dystrophy (RSD). A repeat CT scan revealed extraforaminal, left-sided disk herniation at L4/5. We diagnosed RSD secondary to L5 radiculopathy and performed a left L2, 3 lumbar sympathetic block. Allodynia was relieved, and the patient was able to walk without claudication. Reports of RSD secondary to lumbar disk herniation are rare. In one case, transient lumbar sympathetic block was effective in alleviating symptoms of RSD, although, required surgery. Our patient was more severely disabled than patients in other reports, yet, lumbar sympathetic block still was effective.(ABSTRACT TRUNCATED AT 250 WORDS)