TY - JOUR
T1 - The Effect of Spinopelvic Parameters on the Development of Proximal Junctional Kyphosis in Early Onset
T2 - Mean 4.5-Year Follow-up
AU - Gomez, Jaime A.
AU - Kubat, Ozren
AU - Tovar Castro, Mayra A.
AU - Hanstein, Regina
AU - Flynn, Tara
AU - Lafage, Virginie
AU - Hurry, Jennifer K.
AU - Soroceanu, Alexandra
AU - Schwab, Frank
AU - Skaggs, David L.
AU - El-Hawary, Ron
N1 - Publisher Copyright:
© Journal of Pediatric Orthopaedics. All rights reserved.
PY - 2020/7/1
Y1 - 2020/7/1
N2 - Background:Proximal junctional kyphosis (PJK) is a major complication after posterior spinal surgery. It is diagnosed radiographically based on a proximal junctional angle (PJA) and clinically when proximal extension is required. We hypothesized that abnormal spinopelvic alignment will increase the risk of PJK in children with early-onset scoliosis (EOS).Methods:A retrospective study of 135 children with EOS from 2 registries, who were treated with distraction-based implants. Etiologies included 54 congenital, 10 neuromuscular, 37 syndromic, 32 idiopathic, and 2 unknown. A total of 89 rib-based and 46 spine-based surgeries were performed at a mean age of 5.3±2.83 years. On sagittal radiographs, spinopelvic parameters were measured preoperatively and at last follow-up: scoliosis angle (Cobb method, CA), thoracic kyphosis (TK), lumbar lordosis (LL), pelvic incidence (PI), pelvic tilt (PT), sacral slope and PJA. Radiographic PJK was defined as PJA≥10 degrees and PJA≥10 degrees greater than preoperative measurement. The requirement for the proximal extension of the upper instrumented vertebrae was considered a proximal junctional failure (PJF). Analysis of risk factors for the development of PJK and PJF was performed.Results:At final follow-up (mean: 4.5±2.6 y), CA decreased (P<0.005), LL (P=0.029), and PI (P<0.005) increased, whereas PI-LL (pelvic incidence minus lumbar lordosis) did not change (P=0.706). Overall, 38% of children developed radiographic PJK and 18% developed PJF. Preoperative TK>50 degrees was a risk factor for the development of radiographic PJK (relative risk: 1.67, P=0.04). Children with high postoperative CA [hazard ratio (HR): 1.03, P=0.015], postoperative PT≥30 degrees (HR: 2.77, P=0.043), PI-LL>20 degrees (HR: 2.92, P=0.034), as well as greater preoperative to postoperative changes in PT (HR: 1.05, P=0.004), PI (HR: 1.06, P=0.0004) and PI-LL (HR: 1.03, P=0.013) were more likely to develop PJF. Children with rib-based constructs were less likely to develop radiographic PJK compared with children with spine-based distraction constructs (31% vs. 54%, respectively, P=0.038).Conclusions:In EOS patients undergoing growth-friendly surgery for EOS, preoperative TK>50 degrees was associated with increased risk for radiographic PJK. Postoperative PI-LL>20 degrees, PT≥30 degrees, and overcorrection of PT and PI-LL increased risk for PJF. Rib-based distraction construct decreased the risk for radiographic PJK in contrast with the spine-based constructs.Level of Evidence:Level III.
AB - Background:Proximal junctional kyphosis (PJK) is a major complication after posterior spinal surgery. It is diagnosed radiographically based on a proximal junctional angle (PJA) and clinically when proximal extension is required. We hypothesized that abnormal spinopelvic alignment will increase the risk of PJK in children with early-onset scoliosis (EOS).Methods:A retrospective study of 135 children with EOS from 2 registries, who were treated with distraction-based implants. Etiologies included 54 congenital, 10 neuromuscular, 37 syndromic, 32 idiopathic, and 2 unknown. A total of 89 rib-based and 46 spine-based surgeries were performed at a mean age of 5.3±2.83 years. On sagittal radiographs, spinopelvic parameters were measured preoperatively and at last follow-up: scoliosis angle (Cobb method, CA), thoracic kyphosis (TK), lumbar lordosis (LL), pelvic incidence (PI), pelvic tilt (PT), sacral slope and PJA. Radiographic PJK was defined as PJA≥10 degrees and PJA≥10 degrees greater than preoperative measurement. The requirement for the proximal extension of the upper instrumented vertebrae was considered a proximal junctional failure (PJF). Analysis of risk factors for the development of PJK and PJF was performed.Results:At final follow-up (mean: 4.5±2.6 y), CA decreased (P<0.005), LL (P=0.029), and PI (P<0.005) increased, whereas PI-LL (pelvic incidence minus lumbar lordosis) did not change (P=0.706). Overall, 38% of children developed radiographic PJK and 18% developed PJF. Preoperative TK>50 degrees was a risk factor for the development of radiographic PJK (relative risk: 1.67, P=0.04). Children with high postoperative CA [hazard ratio (HR): 1.03, P=0.015], postoperative PT≥30 degrees (HR: 2.77, P=0.043), PI-LL>20 degrees (HR: 2.92, P=0.034), as well as greater preoperative to postoperative changes in PT (HR: 1.05, P=0.004), PI (HR: 1.06, P=0.0004) and PI-LL (HR: 1.03, P=0.013) were more likely to develop PJF. Children with rib-based constructs were less likely to develop radiographic PJK compared with children with spine-based distraction constructs (31% vs. 54%, respectively, P=0.038).Conclusions:In EOS patients undergoing growth-friendly surgery for EOS, preoperative TK>50 degrees was associated with increased risk for radiographic PJK. Postoperative PI-LL>20 degrees, PT≥30 degrees, and overcorrection of PT and PI-LL increased risk for PJF. Rib-based distraction construct decreased the risk for radiographic PJK in contrast with the spine-based constructs.Level of Evidence:Level III.
KW - EOS
KW - PJK
KW - distraction
KW - distraction-based growth friendly implants
KW - early-onset scoliosis
KW - growth-friendly surgery
KW - pelvic tilt
KW - proximal junctional kyphosis
KW - spine
UR - http://www.scopus.com/inward/record.url?scp=85086007900&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85086007900&partnerID=8YFLogxK
U2 - 10.1097/BPO.0000000000001516
DO - 10.1097/BPO.0000000000001516
M3 - Article
C2 - 32501899
AN - SCOPUS:85086007900
SN - 0271-6798
VL - 40
SP - 261
EP - 266
JO - Journal of Pediatric Orthopaedics
JF - Journal of Pediatric Orthopaedics
IS - 6
ER -