Delta Fixation for High-Grade Spondylolisthesis: Technique, Indications and an Adult Case Report

Spondylisthesis is a condition with 4% prevalence, with high-grade spondylolisthesis (HGS) being 1/5th of total. Majority of HGS cases are reported in children, and uncommonly in adults. High-grade spondylolisthesis is resistant to conservative management and requires surgical fixation. There are multiple options in surgery such as anterior fusion, anterior-posterior fusion, posterolateral bone-only fusion, posterior lumbar interbody fusion, transvertebral pedicle screw fixation, and posterior trans sacral interbody fusion. The main challenge in these surgeries is to achieve adequate decompression, stabilization, and fusion. During these procedures, specially in the reduction of long-standing listhesis, the reduction maneuvers used may lead to neural damage. No reduction needed if sagittal balance balance is present. Methods: We report a case of a 62 yr old female, presenting with chronic low backache for 18 yrs with radiation to bilateral lower limb.  Patient had bilaterally positive SLR and hypoesthesia on the left L5 dermatome, with no motor deficit. Xray and MRI showed grade III spondylolisthesis at L4 over L5 with elongated pars interarticularis. The case was treated by Transdiscal fixation and posterior decompression. Conclusion: On follow-up, for 6 months the patient is asymptomatic with no pain on SLR though paresthesia persisted. The Delta fixation with transdiscal pedicle screws is a good option for adult long-standing high-grade spondylolisthesis with good sagittal balance.