Cauda equina incarceration secondary to dural tears after lumbar microsurgical discectomy

Summary Even minor surgery can cause unexpected complications and symptoms. We report an unusual case of nerve root herniation after microsurgical discectomy. A patient who presented with low-back pain and right sciatica underwent microsurgical discectomy. Two days after the operation and after initial improvement, he suddenly experienced severe low-back pain and right sciatica again. Additionally, persistent muscle cramps and fasciculations in the right lower limb were noted. Magnetic resonance imaging revealed not only the recurrent ruptured disc fragment, but also a cerebrospinal fluid-like intensity accumulating within the epidural space and paraspinal muscle. At surgery, it was observed that nerve roots of the cauda equina were squeezed into the cavity of the intervertebral space. Surgical reposition of nerve roots and dural repair were performed, and the patient eventually recovered. Dural tears should be repaired at the time of the original operation even when the arachnoid appears intact. Dural substitution using polyglycolic acid mesh and fibrin glue is an alternative method for dural repair. An increase in abdominal pressure may play a role in cerebrospinal fluid leakage and extrusion of the cauda equina. The presence of muscle cramps and fasciculations after microsurgical discectomy or any intraspinal procedure may indicate a nerve pinch and entrapment. Nerve root incarceration should be considered in the differential diagnosis.