Finding the Needle in the Haystack—An Unusual Case of Astasia-Abasia Following Sacro-Iliac Joint Injection for Chronic Low Back Pain

We present the case of a 60 yrs old male who, following a routine, uneventful, fluoroscopically guided L5/S1 facet joint rhizolysis and sacro-iliac joint (SIJ) injection developed an unexpected inability to stand or walk, a condition known as astasia-abasia. Initial concern had been that this neurological phenomenon was as a result of complications of his chronic pain intervention. Despite an essentially normal neurological examination and dedicated battery of neurological imaging and special testing, no cause was identified. Over a 7-day period of in-patient admission and physical rehabilitation symptoms resolved entirely. In the course of the workup for this episode, it was suggested that the phenomenon was the result of a side effect of dexamfetamine, an agent that had been prescribed for the patient by his neurologist for treatment of his narcolepsy. On the back of this episode, this treatment was discontinued by his neurologist following an outpatient consultation. Subsequent repeated SIJ injections were entirely uneventful and the patient experienced no further occurrences of this phenomenon.