The dura is the outside lining of the sack containing the nerves and spinal cord. Inside this sack are obviously the nerve roots and fluid called CSF or cerebral spinal fluid. A dural leak is a small tear of the dura and a subsequent leak of this spinal fluid. Repairing the leak is normally a simple matter of some small sutures and a patch of specialized material. Dural leaks are many times avoidable with proper surgical technique but occasionally unavoidable if there is substantial scar from previous surgery, adhesions from prior injury or injection or erosion of the dura from bone spurs. You might be required to lie flat in the hospital for 24 hours after a repair of the dura in the lower back. Lying down head flat on the bed decreases the pressure of the CSF in the lumbar spine and helps to allow the repair to heal.