Clinical and Radiological Outcomes of Surgery for Lumbar Degenerative Spondylolisthesis and Its Impact on Interbody Fusion Cage

Open Access

Abstract

Background: Lumbar degenerative spondylolisthesis (LDS) involves the slippage of a lumbar vertebra, typically less than 30-40%, to avoid severe neurological symptoms. Affecting 5-7% of the general population, it's common in older women, particularly at L4-L5 levels. Most LDS patients are asymptomatic or have mild symptoms manageable with conservative treatment, but surgery is needed for refractory cases. Surgical goals include neural decompression and spine stabilization, using techniques like decompression, fusion, and instrumentation. The introduction of interbody cages aims to enhance fusion and maintain vertebral reduction, though no universal surgical consensus exists. Aim of the study: The study aims to compare the radiological and clinical outcomes of surgical treatment for L4-L5 lumbar degenerative spondylolisthesis (LDS) with and without the use of an interbody fusion cage. Methods & Materials: The study was conducted at the Department of Orthopedics in Holy Family Red Crescent Medical College Hospital, Dhaka, Bangladesh form January 2024 to December 2024. It included fifty patients with L4-L5 lumbar degenerative spondylolisthesis (LDS), treated with decompression, pedicle screw, and rod instrumentation, along with posterolateral fusion (PLF), with or without transforaminal lumbar interbody fusion (TLIF). The patients were divided into two groups of 25 each (Group A: PLF only, Group B: PLF with TLIF). Intraoperative parameters were recorded, and outcomes were assessed using the visual analogue scale (VAS), Oswestry Disability Index (ODI), subjective satisfaction, radiologic union, and loss of reduction. Results were analyzed using SPSS software, version 26. Result: The study compared two patient groups for spinal surgery outcomes (mean age, 52.4±14.1 years; follow-up, 54.1±13.8 months). Baseline demographics and preoperative clinical scores were comparable between groups (p>0.05). TLIF significantly increased operative time (142.8 ± 21.5 vs. 110.6 ± 18.2 min; p<0.001) and blood loss (320.7 ± 68.3 vs. 230.4 ± 55.1 mL; p<0.001). At 12 months, both groups showed significant improvement in VAS and ODI scores, with no significant intergroup difference (p>0.05). Patient satisfaction was similar (PLF 72% vs. PLF+TLIF 80%, p=0.49). Radiologically, complete fusion was higher in the TLIF group (72% vs. 60%, p=0.21), with minimal loss of reduction; cage subsidence occurred in 12% of TLIF cases. Conclusion: In the surgical management of patients with L4-L5 lumbar degenerative spondylolisthesis (LDS), the use of interbody fusion cages may not lead to significant improvements in radiological and clinical outcomes. Additionally, these cages might be linked to an increased risk of complications and morbidity.