TY - JOUR
T1 - Calculation of the target lumbar lordosis angle for restoring an optimal pelvic tilt in elderly patients with adult spinal deformity
AU - Yamato, Yu
AU - Hasegawa, Tomohiko
AU - Kobayashi, Sho
AU - Yasuda, Tatsuya
AU - Togawa, Daisuke
AU - Arima, Hideyuki
AU - Oe, Shin
AU - Iida, Takahiro
AU - Matsumura, Akira
AU - Hosogane, Naobumi
AU - Matsumoto, Morio
AU - Matsuyama, Yukihiro
PY - 2016/2/1
Y1 - 2016/2/1
N2 - Study Design. This investigation consisted of a cross-sectional study and a retrospective multicenter case series. Objective. This investigation sought to identify the ideal lumbar lordosis (LL) angle for restoring an optimal pelvic tilt (PT) in patients with adult spinal deformity (ASD). Summary of Background Data. To achieve successful corrective fusion in ASD patients with sagittal imbalance, it is essential to correct the sagittal spinal alignment and obtain a suitable pelvic inclination. We determined the LL angle that would restore the optimal PT following ASD surgery. Methods. The cross-sectional study included 184 elderly volunteers (mean age 64 years) with an Oswestry Disability Index score less than 20%. The relationship between PT or LL and the pelvic incidence (PI) in normal individuals was investigated. The second study included 116 ASD patients (mean age 66 years) who underwent thoracolumbar corrective fusion at 1 of 4 spine centers. The postoperative PT values were calculated using the parameters measured. On the basis of these studies, an ideal LL angle was determined. Results. In the cross-sectional study, the linear regression equation for the optimal PT as a function of PI was "optimal PT=0.47×PI-7.5." In the second study, the postoperative PT was determined as a function of PI and corrected LL, using the equation "postoperative PT=0.7×PI-0.5×corrected LL+8.1." The target LL angle was determined by mathematically equalizing the PTs of these 2 equations: "target LL=0.45×PI+31.8." Conclusion. The ideal LL angle can be determined using the equation "LL=0.45×PI+31.8," which can be used as a reference during surgical planning in ASD cases.
AB - Study Design. This investigation consisted of a cross-sectional study and a retrospective multicenter case series. Objective. This investigation sought to identify the ideal lumbar lordosis (LL) angle for restoring an optimal pelvic tilt (PT) in patients with adult spinal deformity (ASD). Summary of Background Data. To achieve successful corrective fusion in ASD patients with sagittal imbalance, it is essential to correct the sagittal spinal alignment and obtain a suitable pelvic inclination. We determined the LL angle that would restore the optimal PT following ASD surgery. Methods. The cross-sectional study included 184 elderly volunteers (mean age 64 years) with an Oswestry Disability Index score less than 20%. The relationship between PT or LL and the pelvic incidence (PI) in normal individuals was investigated. The second study included 116 ASD patients (mean age 66 years) who underwent thoracolumbar corrective fusion at 1 of 4 spine centers. The postoperative PT values were calculated using the parameters measured. On the basis of these studies, an ideal LL angle was determined. Results. In the cross-sectional study, the linear regression equation for the optimal PT as a function of PI was "optimal PT=0.47×PI-7.5." In the second study, the postoperative PT was determined as a function of PI and corrected LL, using the equation "postoperative PT=0.7×PI-0.5×corrected LL+8.1." The target LL angle was determined by mathematically equalizing the PTs of these 2 equations: "target LL=0.45×PI+31.8." Conclusion. The ideal LL angle can be determined using the equation "LL=0.45×PI+31.8," which can be used as a reference during surgical planning in ASD cases.
KW - adult spinal deformity
KW - elderly patients
KW - elderly volunteers
KW - pelvic tilt
KW - posterior corrective fusion
KW - posterior surgery
KW - sagittal plane balance formula
KW - spino-pelvic alignment
KW - spino-pelvic parameters
KW - surgical planning
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U2 - 10.1097/BRS.0000000000001209
DO - 10.1097/BRS.0000000000001209
M3 - Article
C2 - 26571165
AN - SCOPUS:84959533441
VL - 41
SP - E211-E217
JO - Spine
JF - Spine
SN - 0362-2436
IS - 4
ER -