Segmental coupling effects during correction of three-dimensional lumbar deformity using lateral lumbar interbody fusion.
PURPOSE
Lateral lumbar interbody fusion (LLIF) has been performed to correct spinal deformity associated with lumbar degenerative disease. Although its usefulness has been studied, there are no reports of quantitative evaluation in three dimensions. Our purpose is to quantitate 3D deformity of the patients with lumbar degenerative disease and correction of the deformity by LLIF using patient-specific 3D CT models.


METHODS
We measured the disc height and 3D alignment of the lumbar spine in 28 patients with degenerative disease undergoing LLIF using patient-specific 3D CT models created preoperatively and 3 months after surgery. The 3D alignment was calculated as wedge, lordosis and axial rotation angles at each motion segment. The disc height and the rotational angles were compared between before and after LLIF.


RESULTS
A strong positive correlation was found between the wedge angle and the axial rotation angles (r = 0.718, P < 0.001) in the patients with lumbar degenerative disease preoperatively. The wedge and axial rotation angles decreased after surgery (P < 0.001 and P < 0.001, respectively). A positive correlation was found between the corrected wedge angle and the corrected axial rotation angle (r = 0.46, P < 0.001).


CONCLUSION
The present study demonstrated positive correlations between the wedge deformity and the axial rotational deformity in the patients with lumbar degenerative disease. The axial rotational deformity was simultaneously corrected with LLIF only by leveling the intervertebral wedge deformity via cage insertion without additional correction procedure. These slides can be retrieved under Electronic Supplementary Material.
['Yamaguchi|Hiroto|H|', 'Nojiri|Hidetoshi|H|0000-0002-2359-3393', 'Miyagawa|Kei|K|', 'Inoue|Nozomu|N|', 'Kaneko|Kazuo|K|']
D000368:Aged D005260:Female D006801:Humans D008141:Lordosis D008159:Lumbar Vertebrae D008161:Lumbosacral Region D008297:Male D008875:Middle Aged D013123:Spinal Fusion
Lateral lumbar interbody fusion (LLIF) 3D alignment Degenerative lumbar scoliosis In vivo 3D CT analysis Lumbar intervertebral deformity