Aim:To evaluate the clinical and radiological outcomes after deformity correction with long-segment (>3 levels) posterior fixation and strategic TLIF in Adult Degenerative Lumbar Scoliosis and to find the correlation between clinical and radiological parameters.Material and Methods:Materials and Methods: This was a prospective single-centre study involving comprehensive clinical data. The Oswestry Disability Index (ODI), visual analog scale (VAS) outcomes, and Scoliosis Research Society (SRS-22) questionnaire were recorded to assess Health Related Quality Of Life (HRQOL). A correlation analysis determined the association between HRQOL and radiographic parameters.Results:Results: A total of 39 consecutive patients (15 males and 24 females) met the inclusion criteria with a mean follow-up of 24.5 ± 7.2 months, and the mean age was 60.13 ± 8.07 years. Factors associated with HRQOL were significantly improved post-operation. VAS back scores improved from 7.54 ± 1.33 to 2.42 ± 0.17 (p < 0.0001), and VAS leg scores improved from 6.72 ± 1.32 to 1.37 ± 0.28. ODI scores improved from 70.27 ± 18.04% to 27 ± 7.07% (p < 0.0001). SRS scores significantly improved in all domains except self-image. Coronal Cobb angles were corrected from 21.23 ± 8.13 to 3.4 ± 1.83 (88% correction, p = 0.014). Lumbar lordosis (LL) improved from 22.47 ± 12.32 to 39.73 ± 4.06 (p = 0.023). The Sagittal Vertical Axis (SVA) improved from 48.7 ± 22.7 mm to 37.17 ± 25.13 mm (p = 0.027). Significant changes were observed in Pelvic Tilt (PT) , Sacral Slope (SS) and Pelvic Incidence – Lumbar lordosis(PI-LL). Significant correlations were found between changes in VAS and LL, PT, SS, SVA, and PI-LL. No coronal parameter showed a correlation with clinical outcomes.Conclusion:Conclusion: Long-segment posterior fixation and strategic TLIF provide good clinical and radiological outcomes. Restoration of sagittal and spinopelvic parameters is more crucial than coronal deformity correction for good clinical outcomes.