Sorry you are having this problem. I cannot say I've had this experience and it doesn't sound like you should still be in pain from the procedure. Usually, even with complications, people are not still sore or whatever, this far afterward.

All I can think of is perhaps the doctor knicked the S1 nerve somehow. I think what you had was a caudal injection. This is often done after a lower lumbar fusion. The catheter is threaded up through the sciatic notch and up to the L5-S1 area. The medicine is injected through the catheter, and the medicine then spread out through the area of the S1 nerve root.

If this procedure does not provide any results, the doctor can do a similar procedure as a transforaminal steroid injection, which would go in to the foraminal space of the L5-S1 disk or that area....

Have you been in touch with the doctor who performed the procedure? If so, what did he have to say??