L5 Nerve Root Radiculopathy as a Rare Complication Following Oblique Lateral Interbody Fusion at L5/S1 Combined With Posterior Fixation via Percutaneous Pedicle Screws for Adult Spinal Deformity.

Oblique lateral interbody fusion (OLIF) is an established and less invasive surgical approach for patients with adult spinal deformities. This method can also be applied to the L5/S1 region (termed "OLIF51"); however, reports on L5 nerve root radiculopathy as a rare complication of OLIF51 are limited. Here, we present the case of a 77-year-old woman with progressive adult spinal deformity who was followed up after an initial OLIF for the L3/4 and L4/5 levels. An additional operation was performed to resolve ambulation difficulty and back pain related to adult spinal deformity. Circumferential fixation was performed over two sessions. Initially, OLIF51 was performed concurrently with OLIF for L1/2 and L2/3. Eight days later, posterior fixation surgery from T10 to the ilium via percutaneous pedicle screws was performed. Two days after the second operation, the patient started complaining of left L5 nerve root radiculopathy, for which medication and rehabilitation were both ineffective. Retrospectively, we identified that the left L5/S1 foramen narrowed after the lordotic correction by OLIF51 and posterior fixation. Additionally, posterior facetectomy for L5/S1 was performed, and the left L5 nerve root radiculopathy was resolved. L5 nerve root radiculopathy can develop as a rare complication of OLIF51. Neurosurgeons should be aware of this rare complication related to OLIF51.