P87. Does short segment reduction and fusion (TLIF) of spondylolytic spondylolisthesis normalize lumbar lordosis and improve spino-pelvic alignment?

• Published in: The spine journal Vol. 20; no. 9; p. S188
• Main Authors: Robinson, Tom, Boddice, Timothy, Fitzjohn, Harry, Shah, Rajesh R.
• Format: Journal Article
• Language: English
• Published: Elsevier Inc 01-09-2020
• ISSN: 1529-9430; 1878-1632
• DOI: 10.1016/j.spinee.2020.05.485

Spondylolytic spondylolisthesis is commonly associated with back pain and neurological symptoms. The primary localized kyphotic deformity at the level of the spondylolisthesis is compensated by increased lordosis across the remaining lumbar spine giving rise to a hyperlordotic lumbar spine. There is usually an associated increase in sacral slope and a corresponding decrease in pelvic tilt.
This study was done to investigate the influence of short segment reduction and fusion (TLIF) for spondylolytic spondylolisthesis on the increased lumbar lordosis and the spino-pelvic alignment.
Retrospective radiological analysis by two independent observers of standing preoperative and postoperative lumbar spine radiographs. Ethical approval was obtained for the study from the Institute Ethics Committee.
Thirty-seven consecutive patients from a single surgeon series of spondylolytic spondylolisthesis undergoing reduction and fusion (TLIF) performed between 2013 and 2019.
Measurements of the lumbar lordosis across the lumbar spine as a whole and individual motion segments, and sacral slope were taken using pre- and postoperative standing radiographs.
Two independent observers, blinded of each other, reviewed the pre- and postoperative standing radiographs. Using PACS software they measured the lumbar lordosis across the lumbar spine as a whole and individual motion segments, and sacral slope. The lumber lordosis was measured from the superior border of S1 to superior border of L1.
Twenty-seven fusions were performed at L5/S1, nine at L4/5 and one at L3/4. Normalization of lordosis was noted at all spinal levels, including distant from the surgical site. Overall mean lumbar lordosis reduced from 63.43 degrees to 48.89 degrees (p <0.0001) and sacral slope from 45.78 degrees to 39.12 degrees (p=0.0001). The lumbar lordosis was also mapped level-by-level with the greatest proportional change seen at L1/2, where a 27% reduction in the lordosis angle was noted. The greatest angular correction was consistently at L5/S1 with a mean reduction of 3.55 degrees (p=0.009). The decrease in sacral slope following reduction of the spondylolisthesis is likely to be a contributory factor for this reduction.
This study shows that short segment reduction and fusion for spondylolytic spondylolisthesis can normalize lumbar lordosis at all levels of the lumbar spine and this occurs level-by-level. There is also an associated spontaneous reduction in the sacral slope and therefore a corresponding improvement in the pelvic tilt leading to improved spino-pelvic alignment.
This abstract does not discuss or include any applicable devices or drugs.