///2014 Abstract Details
2014 Abstract Details2019-07-18T14:34:47+00:00

Prolonged Postpartum Foot Drop in a Patient with Congenital Perineural Cysts

Abstract Number: T-51
Abstract Type: Case Report/Case Series

Li-Kuei Chen MD, PhD1 ; Barbara L Leighton MD2

Background:

A healthy 25 y/o parturient presented for elective cesarean delivery. We performed combined spinal-epidural anesthesia as a two-step procedure. We inserted the epidural catheter uneventfully at L3-4. The first attempt at placement of a 27 gauge spinal needle at L4-5 produced a severe right leg paresthesia. No drug was injected. The spinal needle was removed and reintroduced at L4-5. We obtained clear cerebrospinal fluid (CSF), there was no paresthesia, and we injected 11mg 0.5% hyperbaric bupivacaine intrathecally to achieve a T4 level. Neurologic examination on postoperative day 1 was normal except for weak right ankle dorsiflexion, numbness over the lateral right calf, significant right foot drop, and a limping gait requiring a walker. One month later, a significant right foot drop with a limping gait persisted. A plain film of the lumbar spine was negative. A nerve conduction velocity study showed reduced amplitude of compound muscle action potential in the right peroneal nerve and reduced amplitude of sensory action potential in the right superficial peroneal nerves. The F-wave study showed absence of F response and/or presence of A waves in the right peroneal and tibial nerves and prolongation of minimal F-wave latency in the left peroneal and tibial nerves. These findings suggested bilateral lumbosacral radiculopathy, more severe on the right side, or right superficial peroneal neuropathy. Two months after delivery, magnetic resonance imaging found perineural cysts bilaterally along the S1 and S2 nerve roots.(Figure) All symptoms resolved spontaneously 3 months after delivery.

Discussion:

Perineural (Tarlov) cysts form at the junction of sacral dorsal root ganglions and posterior nerve roots. They contain CSF but do not communicate with the subarachnoid space. Tarlov cysts enlarge with age and can cause pain and severe sensory and motor dysfunction. A case of new-onset cauda equina syndrome after uneventful combined spinal-epidural anesthesia has been reported in a patient with Tarlov cysts.(1) We do not know if the paresthesia during spinal placement contributed to our patient’s neuropathy.

1. Ishiguro S. Asian Spine J, 2013;7:232-5



SOAP 2014