DOI: https://doi.org/10.36347/sjmcr.2026.v14i09.019

Pages: 2036-2038

Spinal anesthesia in patients with a history of posterior lumbar interbody fusion (PLIF) can be technically challenging due to altered anatomy, epidural fibrosis, and dural thickening. We reports a case where spinal anesthesia initially failed using a 25-gauge (G) Quincke needle despite free cerebrospinal fluid (CSF) flow, but was subsequently achieved by switching to a 22G Quincke needle. An 85-year-old female with a history of L4–5 PLIF was scheduled for open reduction and internal fixation of a femur fracture under spinal anesthesia. A paramedian approach was performed at the L3–4 level using a 25G Quincke needle. Free flow of clear CSF was observed; however, local anesthetic could not be injected due to absolute resistance, even after 360-degree needle rotation. Suspecting dural tenting and partial dural penetration, the needle was removed, and a 22G Quincke needle was inserted along the same trajectory. Following CSF re-confirmation, the anesthetic was injected smoothly without resistance, resulting in a successful sensory and motor block without complications. In patients with prior lumbar surgery, dural thickening or fibrosis can lead to dural tenting with a fine 25G needle, causing partial penetration where CSF flows out but drug administration is obstructed. Switching to a larger gauge (22G) needle with greater flexural rigidity can effectively overcome dural resistance and ensure successful intrathecal drug delivery.