PMID- 34388707
OWN - NLM
STAT- Publisher
LR  - 20240220
IS  - 1547-5646 (Electronic)
IS  - 1547-5646 (Linking)
DP  - 2021 Aug 13
TI  - Understanding sagittal compensation in adult spinal deformity patients: 
      relationship between pelvic tilt and lower-extremity position.
PG  - 1-8
LID - 2021.1.SPINE201660 [pii]
LID - 10.3171/2021.1.SPINE201660 [doi]
AB  - OBJECTIVE: In adult spinal deformity (ASD), quantifying preoperative 
      lower-extremity (LE) compensation is important in formulating an operative plan 
      to achieve optimal global sagittal alignment. Whole-body radiographs are not 
      always available. This study evaluated the possibility of estimating LE 
      compensation without whole-body radiographs. METHODS: In total, 200 consecutive 
      ASD patients with full-body radiographic assessment were categorized into the 
      following three groups according to their cranio-hip balance (distance from the 
      cranial sagittal vertical axis to the hip axis [CrSVA-H]): group 1, 
      anterior-shift (A-shift) group (CrSVA-H > 40 mm); group 2, balanced group, -40 mm 
      < CrSVA-H < 40 mm; and group 3, posterior-shift (P-shift) group, CrSVA-H < -40 
      mm. After analyzing the correlation between CrSVA-H, pelvic tilt (PT), and LE 
      parameters, the cutoff PT and PT/pelvic incidence (PI) values that correlated 
      with the presence of LE compensation were determined. Previously published data 
      from asymptomatic volunteers were used as a baseline threshold (sacrofemoral 
      angle [SFA] > 217.0 degrees  and knee flexion angle [KA] > 11.0 degrees ). RESULTS: Among the 
      hip, knee, and ankle, only KA showed a significant increase in the A-shift group 
      compared to the other two groups (p < 0.01). With a wide threshold (SFA > 208.0 degrees  
      and KA > 5.0 degrees ), 84.9% of the A-shift group showed LE compensation (hip or knee or 
      both), which was a significantly greater percentage than those in the balanced 
      and P-shift groups (48.4% and 51.9%, p < 0.01). With a narrow threshold (SFA > 
      217.0 degrees  and KA > 11.0 degrees ), 62.2% of the A-shift group showed any LE compensation, 
      which was also a higher percentage than the other two groups. The CrSVA-H was 
      moderately correlated with KA (r = 0.502), but had no correlation with PT, SFA, 
      and ankle dorsiflexion angle (AA). PT showed a moderate/strong correlation with 
      SFA, KA, and AA (r = 0.846, 0.624, and 0.622, respectively). With receiver 
      operating characteristic curves, the authors determined that a 23.0 degrees  PT with 
      PT/PI > 0.46 predicts the presence of any type of LE compensation with use of the 
      wide threshold. CONCLUSIONS: ASD patients with increased CrSVA-H, which 
      represents cranio-hip anterior imbalance, demonstrated a higher prevalence of LE 
      compensation, especially knee flexion, compared to those with neutral and 
      posterior shift of CrSVA. PT represents the extent of LE compensation in patients 
      with spinal sagittal malalignment. Using the cutoff value of PT determined in 
      this study, surgeons can preoperatively estimate the extent of LE compensation 
      without obtaining a full-body radiograph.
FAU - Shimizu, Takayoshi
AU  - Shimizu T
AD  - 1Department of Orthopaedic Surgery, Columbia University Medical Center, Och Spine 
      Hospital at NewYork-Presbyterian, New York, New York; and.
AD  - 2Department of Orthopaedic Surgery, Kyoto University, Graduate School of 
      Medicine, Kyoto, Japan.
FAU - Cerpa, Meghan
AU  - Cerpa M
AD  - 1Department of Orthopaedic Surgery, Columbia University Medical Center, Och Spine 
      Hospital at NewYork-Presbyterian, New York, New York; and.
FAU - Lenke, Lawrence G
AU  - Lenke LG
AD  - 1Department of Orthopaedic Surgery, Columbia University Medical Center, Och Spine 
      Hospital at NewYork-Presbyterian, New York, New York; and.
LA  - eng
PT  - Journal Article
DEP - 20210813
PL  - United States
TA  - J Neurosurg Spine
JT  - Journal of neurosurgery. Spine
JID - 101223545
SB  - IM
OTO - NOTNLM
OT  - adult spinal deformity
OT  - compensation
OT  - lower extremities
OT  - sagittal alignment
EDAT- 2021/08/14 06:00
MHDA- 2021/08/14 06:00
CRDT- 2021/08/13 20:24
PHST- 2020/09/12 00:00 [received]
PHST- 2021/01/11 00:00 [accepted]
PHST- 2021/08/13 20:24 [entrez]
PHST- 2021/08/14 06:00 [pubmed]
PHST- 2021/08/14 06:00 [medline]
AID - 2021.1.SPINE201660 [pii]
AID - 10.3171/2021.1.SPINE201660 [doi]
PST - aheadofprint
SO  - J Neurosurg Spine. 2021 Aug 13:1-8. doi: 10.3171/2021.1.SPINE201660.