Inguinal hernia following oblique lateral interbody fusion: First case report and pathophysiological analysis

Background: Oblique lateral interbody fusion (OLIF) is a minimally invasive technique with various complications. Here, a 55-year-old female karate instructor with previous L4/5 laminectomy underwent L4/5 OLIF that resulted in an inguinal hernia. Case Description: A 55-year-old female karate instructor with previous L4/5 laminectomy underwent L4/5 OLIF for symptomatic foraminal stenosis. Postoperatively, she experienced immediate symptom relief, but developed a left lower abdominal bulge on postoperative day 13. Despite negative computed tomography findings, laparoscopic exploration at 6 months confirmed the presence of an indirect inguinal hernia, which was successfully repaired. Three surgical factors likely led to this hernia (1) retroperitoneal dissection requiring incision of the transverse fascia, causing mechanical stress, collagen reduction/inflammatory changes that weakened the posterior wall of the inguinal canal; (2) the lumbar corset increased the intra-abdominal pressure (2–4 mmHg average, peaks up to 10 mmHg) redirecting pressure caudally toward Hesselbach’s triangle; and (3) occupational activities required repetitive Valsalva maneuvers, thus imposing recurrent pressure loading on weakened fascial structures. Conclusion: This report documents that a 55-year-old female karate instructor with previous L4/5 laminectomy following a L4/5 OLIF developed a delayed inguinal hernia. Spine surgeons should include inguinal hernia in differential diagnosis of postoperative lower abdominal bulging, and emphasize the need for meticulous fascial reconstruction.