The Quest of Sagittal Balance Parameters and Clinical Outcome after Short Segment Spinal Fusion

Sagittal imbalance leads to muscular distress and results in low back pain.

This study scrutinize the segmental impact of short spinal fusion on spinopelvic parameters and the global patient's clinical outcome.

A retrospective analysis evaluated 56-patients who underwent lumbar fusion surgery at Klinikum Dortmund, from July 2013 to February 2014. The population was allocated into two groups: (1-level group), (2-levels group). EOS imaging applied for radiological evaluation and measurements of the following spinopelvic parameters: pelvic incidence (PI), sacral slope (SS), pelvic tilt (SS), lumbar lordosis (LL), and sagittal vertical axis (SVA). The radiological measurements were implemented during the preoperative, postoperative, 3 months and 1 year follow-up visits. All patients completed clinical questionnaires.

Statistically, the Pearson correlation coefficient revealed in the 1-level group that the clinical parameters correlated with the PT (R=0.40), SSA (R=-0.38) and SVA (R=-0.41) (p<0.05). While clinically, the mean preoperative VAS and mean ODI improved significantly in both groups.There was also a high correspondence between LL and SS (R=0.90); this relationship persisted at the same level even after a year. For the 2-level group, the only parameter that was interrelated with clinical parameters was the SVA (R=0.49) (p<0.05). There was also a high correlation between LL and SS (R=0.88).

Scrutiny conducted showed: Patient with one level would improve clinically in terms of pain and radiculopathy, with only small alterations in spino-pelvic parameters. Meanwhile, two-level fusions have a statistically substantial clinical improvement interrelated to re-establishment of lumbar lordosis and sagittal vertical axis.