A Novel "Flying Owl Sign" to Predict Favorable Patient-Reported Outcomes Following Full-Endoscopic Lumbar Discectomy

Area of Science:

• Radiology
• Neurosurgery
• Orthopedic Surgery

Background:

• Lumbar disc herniation (LDH) is a common condition causing significant pain and disability.
• Assessing specific imaging findings can improve understanding of LDH subtypes and surgical outcomes.
• Patient-reported outcomes (PROs) are crucial for evaluating surgical success in LDH management.

Purpose of the Study:

• To introduce and define the novel "Flying owl sign" on MRI for characterizing a specific type of LDH.
• To investigate the association between the presence of the "Flying owl sign" and PROs after full-endoscopic lumbar discectomy.
• To determine if the "Flying owl sign" is a predictive factor for surgical success and patient satisfaction.

Main Methods:

• Retrospective case-control study design.
• Inclusion of patients with LDH who underwent full-endoscopic lumbar discectomy.
• Utilized propensity score matching to create comparable groups.
• Multivariable logistic regression analysis to assess the relationship between the "Flying owl sign" and PROs.

Main Results:

• The "Flying owl sign" was identified in 10.21% of patients.
• Patients with the "Flying owl sign" showed significantly improved VAS scores (P=0.022).
• The "Flying owl sign" group reported higher patient satisfaction (P=0.016) and lower residual low back pain (P=0.013).
• Multivariate analysis confirmed the "Flying owl sign" as a protective factor for satisfaction (OR=3.544, P=0.018).

Conclusions:

• The "Flying owl sign" represents a specific LDH type, characterized by giant disc herniation and an intact posterior longitudinal ligament.
• "Flying owl sign" presence is associated with improved postoperative efficacy and patient satisfaction following discectomy.
• This imaging finding may help predict favorable outcomes and reduce residual pain after surgery for lumbar disc herniation.