PURPOSE: The goal of this study is to determine the relationship of radiological grading scales of lumbar degenerative disc disease (DDD) with postoperative pain intensity, functional impairment, and health-related quality of life (HRQoL). METHODS: Response to surgical treatment at 6 weeks (W6) on the visual analogue scale (VAS) for back and leg pain, Oswestry-Disability (ODI) and Roland-Morris Disability Index (RMDI), Timed Up and Go (TUG) test, EuroQol (EQ) 5D, and Short-Form Health-Survey (SF-12) physical component summary (PCS) was compared between patients with different Modic (MOD) and Pfirrmann (PFI) grades. Longitudinal outcomes at day 3 (D3), W6, 6 months (M6), and 1 year (Y1) were compared. RESULTS: The study included 338 patients (mean age, 58.6 years), of which n = 202 (59.8%) had MOD 1-3 and n = 217 (64.2%) PFI 4-5 changes. Patients with MOD 1-3 were as likely as patients without MOD changes to be treatment-responders at W6 in terms of VAS leg pain, ODI, RMDI, TUG, EQ5D, and SF-12 PCS. Similarly, patients with PFI 4-5 were as likely as patients with PFI 1-3 changes to be treatment-responders at W6. Longitudinal outcomes were similar at D3, W6, M6, and Y1 between patients with and without MOD changes. Patients with PFI 4-5 fared similar to those with PFI 1-3 except for inferior HRQoL on the SF-12 PCS metric at Y1. CONCLUSIONS: There was no distinct relationship between commonly used radiological grading scales of lumbar DDD with clinical outcome. Therefore, no prognosis should be made on the grounds of preoperative PFI and MOD classifications for patients undergoing spine surgery for lumbar DDD. KEYWORDS: