Does the change of pelvic incidence predict the listhesis progression among pediatric patients with Low-Grade Spondylolisthesis

Abstract

Abstract Purpose Observational studies suggest that most low-grade patients treated nonoperatively will have a successful clinical outcome. However, the changes in pelvic incidence as related to the risk of progression remain unknown. Methods The complete records of 301 prospective patients (129 males 172 females) with low-grade spondylolisthesis aged 12.3 years ± 3.1 years were reviewed. Radiological parameters (pelvic incidence, lumbosacral angle, and percentage of slip) and quality of life were measured at the first visit and a minimum 2-year follow-up. Patients with an increase in pelvic incidence by more than 5 degrees at the last follow-up were included in group 1, and otherwise included in group 2. Results The average follow-up time is 4.6 ± 2.3 years. The slip percentage was 14.6 ± 8.8 at the initial visit and 15.8 ± 9 at the last follow-up (P < 0.05). There were 66 patients in group 1 and 233 patients in group 2. There was no difference in slip progression or lumbosacral progression between the two groups. The pelvic incidence was 56.1 ± 12.9 at the initial visit and 58.7 ± 13.4 at the last follow-up (P < 0.05). There was a significant increase in pelvic incidence during follow-up. The change in pelvic incidence was not related to lumbosacral angle or slip percentage. Conclusion Pelvic incidence increased significantly during follow-up, but the changes in pelvic incidence were not associated with the progression of spondylolisthesis in terms of slip percentage and lumbosacral angle. Pelvic incidence is not likely to be a risk factor for progression in low-grade spondylolisthesis.