Study of functional outcome in low grade spondylolisthesis operated by pedicular screw instrumentation and fusion

Background: Functional outcome following instrumental spinal surgery for spondylolisthesis in physically energetic patients is crucial. The present study was undertaken to evaluate the functional outcome of low-grade spondylolisthesis accompanied by low back pain with or without radiculopathy, with standard surgical procedure posterior lumbar interbody fusion with instrumentation. Method: In this study total of 40 patients were operated on for low-grade spondylolisthesis by posterior stabilization using a pedicular screw rod system and posterior lumbar interbody fusion. All the patients were followed up till 6 months after surgery and functional outcomes were noted. Results: Assessment of this series it was observed that, 57.5% of the patient had excellent outcome, 37.5% had a good outcome and 97.5% of the study population had satisfactory outcome (improvement in clinical results). There was a significant improvement in pain intensity, walking, lifting, standing, sleeping after surgery. The mean ODI difference between preoperative and post-operative at 6 months follow up was 36.12% (16.75). In the outcome, 62.5% of the patient consisted of severe disability and 32.5% were with moderate disability (total-95%) while postoperative 87.5% were with a minimal disability and only 2.5% of the study population had worsened i.e crippled. Conclusion: The study concluded that surgery in form of decompression with instrumentation and posterior lumbar interbody is a safe and effective method to treat spondylolisthesis. functional


Introduction
Chronic low back pain (LBP) affects the physical function and quality of life of a large number of individual and one of the causes of back pain is spondylolisthesis. In this condition one vertebra (usually L5) becomes misaligned anteriorly (slips forward) concerning the vertebra below. However, the incidence of spondylolisthesis is 5-6% in white males and 2-3% in females, the most common level is a lumbosacral junction (L5-S1) in 82% and

Materials and Methods
The present prospective observational study was conducted in the Department of Orthopaedics at K.  All patients were evaluated in the outpatient clinic regularly as follows 2 weeks, 3 weeks, 6 weeks, 12 weeks and finally at 6 months. ODI was used for assessment at 6 months again.

Results
A total of 40 cases of low-grade spondylolisthesis were enrolled in the study, among them, 17 (42.50%) were male and 23 (57.50%) were female.
The maximum numbers of patients were in the age group of 41-60 years (75%) (   After surgery, there was a significant improvement in the quality of activities of daily living including pain intensity, walking, lifting, standing, sleeping as shown in Table 3.  In the outcome of our study 62.5% of the patient consisted of severe disability and 32.5% were with moderate disability(total-95%) while postoperative 87.5% were with a minimal disability and only 2.5% of the study population had worsened i.e crippled, (Table 4).   In all our patients, deep vein antithrombotic prophylaxis was given with low molecular weight heparin (Rivaroxaban) for 5 days post-operatively and none of them developed DVT. In the present study spondylolisthesis indirect reduction was achieved through pedicle screws with the release of the disc and soft tissues. In addition to a wide neural decompression, a discectomy and curettage of the endplate were performed for the PLIF cage insertion which maintained the reduction and improved the neural foraminal dimensions significantly.
Moreover, the results of prospectively evaluated ODI based outcomes indicated that age and sex were not related to poorer outcome or complication in the current study. The surgery-related results indicated that outcomes were significantly improved after surgery, and these data support the need for a prospective randomized multicentre trial using various scoring system (Roland morris scale, quality of life) and radiological evaluation to determine the most appropriate method for the benefit of patients.
There are several strengths of the study: 1) All types of spondylolisthesis were taken into consideration i.e isthmic and degenerative spondylolisthesis, 2) only low-grade spondylolisthesis were presented in this series which have been less studied, 3) all patients had undergone the same surgery for a single level spondylolisthesis.

Conclusion
Posterior lumbar interbody fusion and spinal decompression is an effective method in the treatment of spondylolisthesis, as it provided good spinal fusion, less complication with satisfactory clinical outcome and reduction of a slip in low grade especially.
What does the study add to the existing knowledge?
This surgery has gradually gained good popularity since its inception amongst the patient population reporting at our institute. However, this procedure provides a better outcome and with experience, proper instrumentation, proper and fusion techniques, and gives excellent results with minimal complication rate. Good outcome was mainly related to the preoperative neurological deficits. Apart from surgical management, modification of the lifestyle is also recommended to avoid failure of the surgery.