Purpose <p>This study aimed to identify independent risk factors for requiring multiple debridements in patients with postoperative spinal infections and to assess their clinical implications for management.</p> Methods <p>We conducted a retrospective cohort study of 135 patients who developed postoperative spinal infections at a single institution between 2014 and 2024. Data on demographic variables, comorbidities, surgical factors, infection characteristics, and laboratory markers were collected. Predictors for multiple debridements were identified using univariate and multivariable logistic regression, followed by nomogram construction. Kaplan-Meier survival analysis was employed to evaluate the relationship between the timing of debridement and clinical outcomes.</p> Results <p>37 patients (27.4%) required multiple debridements. Independent predictors included incision fat thickness (OR = 1.29; 95% CI:1.16–1.44, <i>p</i> &lt; 0.001), MRSA positivity (OR = 3.48; 95% CI:1.01–12.02, <i>p</i> = 0.048), and postoperative albumin (OR = 0.86; 95% CI:0.75–0.98, <i>p</i> = 0.035). The nomogram integrating these parameters achieved high discrimination (AUC = 0.886; 81.5% accuracy). Patients requiring multiple debridements had prolonged hospitalization (52.75 vs. 20.27 days, <i>p</i> &lt; 0.001), higher fixation failure (48.6% vs. 6.1%, <i>p</i> &lt; 0.001), and reduced infection resolution (8.1% vs. 100%, <i>p</i> &lt; 0.001). Debridement timing (≤ 3/7 days) showed no association with outcomes (<i>p</i> = 0.096).</p> Conclusion <p>Incision fat thickness and MRSA positivity were independent risk factors for multiple debridements in postoperative spinal infections, while higher postoperative albumin conferred protection. The nomogram provides a practical framework for clinicians to identify high-risk patients. This identification could potentially guide more vigilant monitoring and aggressive preventative strategies.</p>