Pedicle Involvement Is Associated with Preoperative Neurological Deficit in Metastatic Spinal Cord Compression: A Single-Institution Cohort Study

OBJECTIVE: To evaluate whether pedicle involvement - tumor invasion of Weinstein-Boriani-Biagini zones 3, 4, 9, or 10 - is associated with preoperative neurological deficit in metastatic spinal cord compression, and to compare early recovery between surgical approaches in this subgroup. METHODS: Thirty-nine patients with high-grade epidural spinal cord compression (grade ≥2) treated at a single tertiary center in Taiwan between September 2021 and December 2025 were reviewed retrospectively. The primary outcome was the American Spinal Injury Association motor score (AMS). Interobserver reliability was quantified by Cohen's kappa. Multiple linear regression was supported by variance inflation factors, bootstrap validation, and a prespecified incremental comparison against conventional radiographic measures. Early recovery (ΔAMS) was compared between corpectomy and laminectomy. Corpectomy showed greater early ΔAMS than laminectomy (median 14.5 vs. 4.5, P = 0.042) but longer operative time and greater blood loss; complication (47% vs. 17%) and 30-day mortality (16% vs. 0%) differences were nonsignificant but underpowered. CONCLUSIONS: In our practice, pedicle involvement was independently associated with lower preoperative AMS and added explanatory value beyond conventional radiographic measures. The surgical comparison was small, underpowered, and exploratory.