Ventral Subdural Malposition – Highly Rare Complication ofLong-Lasting Cathetrization of the Lumbar Epidural Space

Overview

A case-report of a 53-year-old man with severe low back pain with subdural dislocation(between the dura and arachnoidea spinalis) of an epidural catheter hasbeen presented. The injection of 10 ml of 0.25% bupivacaine wih 2.5 mg of morphineevery 8 hours via epidural catheter provided excellent low back pain relief.After five and half months the same injection caused unexpected progressive lossof strength and sensation in both lower extremities, distal part of the trunk, paraesthesiain the upper right extremity and mild dyspnea within several minutesafter the injection. X-ray control after injecting 3 ml of ioversol revealed the ventralsubdural malposition of a catheter with spreading the radiopaque contrastmedium up to Th3 level. The diagnosis of subdural block must be considered inpatients with unusual presentation even after long-lasting successful epidural painmanagement. A radiopaque contrast medium radiograph may adequately demonstratesubdural placement in some cases, although computed tomography or magneticresonance image should be performed if any doubt arises.

Key words:
subdural block, epidural catheter, low back pain, chronic pain.