Browsing by Subject "DJK"

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    ItemOpen Access
    Despite a Multifactorial Etiology, Rates of Distal Junctional Kyphosis After Adult Cervical Deformity Corrective Surgery Can be Dramatically Diminished by Optimizing Age Specific Radiographic Improvement.
    (Global spine journal, 2024-11) Mir, Jamshaid M; Onafowokan, Oluwatobi O; Jankowski, Pawel P; Krol, Oscar; Williamson, Tyler; Das, Ankita; Thomas, Zach; Padon, Benjamin; Schoenfeld, Andrew J; Janjua, Muhammad Burhan; Passias, Peter G

    Study design

    Retrospective cohort study of a prospectively collected single-center database.

    Objective

    Distal Junctional Kyphosis (DJK) is one of the most common complications in adult cervical deformity (ACD) correction. The utility of radiographic alignment alone in predicting and minimizing DJK occurrence warrants further study. To investigate the impact of post-operative radiographic alignment on development of DJK in ACD patients.

    Methods

    ACD patients (≥18 yrs) with complete baseline (BL) and two-year (2Y) radiographic data were included. DJF was defined as DJK greater than 15° (Passias et al) or DJK with reop. Multivariable logistic regression (MVA) identified 3-month predictors of DJK. Conditional inference tree (CIT) machine learning analysis determined threshold cutoffs. Radiographic predictors were combined in a model to determine predictive value using area under the curve (AUC) methodology. "Match" refers to ideal age-adjusted alignment.

    Results

    140 cervical deformity patients met inclusion criteria (61.3 yrs, 67% F, BMI: 29 kg/m2, CCI: 0.96 ± 1.3). Surgically, 51.3% had osteotomies, 47.1% had a posterior approach, 34.5% combined approach, 18.5% anterior approach, with an average 7.6 ± 3.8 levels fused and EBL of 824 mL. Overall, 33 patients (23.6%) developed DJK, and 11 patients (9%) developed DJF. MVA controlling for age, and baseline deformity, followed by CIT found 3M cSVA <3.7 cm (OR: .2, 95% CI:.06-.6), and TK T4-T12 <50 (OR:.17, 95% CI:.05-.5, both P < .05) were significant predictors of a lower likelihood of DJK. Receiver operator curve AUC using age, T1S match, TS-CL match, LL-TK match, cSVA <3.7 cm, and T4-T12 <50 predicted DJK with an AUC of .91 for DJK by 2Y, and .88 for DJF by 2Y.

    Conclusion

    These findings suggest post-operative radiographic alignment is strongly associated with distal junctional kyphosis. When utilizing age-adjusted realignment in addition to newly developed thresholds, a suggested post-operative cSVA target of 3.7 cm and thoracic kyphosis less than 50, it is possible to substantially reduce the occurrence of distal junctional kyphosis and distal junctional failure.
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    ItemOpen Access
    Predicting development of severe clinically relevant distal junctional kyphosis following adult cervical deformity surgery, with further distinction from mild asymptomatic episodes.
    (Journal of neurosurgery. Spine, 2021-12) Passias, Peter G; Naessig, Sara; Kummer, Nicholas; Passfall, Lara; Lafage, Renaud; Lafage, Virginie; Line, Breton; Diebo, Bassel G; Protopsaltis, Themistocles; Kim, Han Jo; Eastlack, Robert; Soroceanu, Alex; Klineberg, Eric O; Hart, Robert A; Burton, Douglas; Bess, Shay; Schwab, Frank; Shaffrey, Christopher I; Smith, Justin S; Ames, Christopher P
    OBJECTIVE:This retrospective cohort study aimed to develop a formal predictive model distinguishing between symptomatic and asymptomatic distal junctional kyphosis (DJK). In this study the authors identified a DJK rate of 32.2%. Predictive models were created that can be used with high reliability to help distinguish between severe symptomatic DJK and mild asymptomatic DJK through the use of surgical factors, radiographic parameters, and patient variables. METHODS:Patients with cervical deformity (CD) were stratified into asymptomatic and symptomatic DJK groups. Symptomatic: 1) DJK angle (DJKA) > 10° and either reoperation due to DJK or > 1 new-onset neurological sequela related to DJK; or 2) either a DJKA > 20° or ∆DJKA > 20°. Asymptomatic: ∆DJK > 10° in the absence of neurological sequelae. Stepwise logistic regressions were used to identify factors associated with these types of DJK. Decision tree analysis established cutoffs. RESULTS:A total of 99 patients with CD were included, with 32.2% developing DJK (34.3% asymptomatic, 65.7% symptomatic). A total of 37.5% of asymptomatic patients received a reoperation versus 62.5% symptomatic patients. Multivariate analysis identified independent baseline factors for developing symptomatic DJK as follows: pelvic incidence (OR 1.02); preoperative cervical flexibility (OR 1.04); and combined approach (OR 6.2). Having abnormal hyperkyphosis in the thoracic spine, more so than abnormal cervical lordosis, was a factor for developing symptomatic disease when analyzed against asymptomatic patients (OR 1.2). Predictive modeling identified factors that were predictive of symptomatic versus no DJK, as follows: myelopathy (modified Japanese Orthopaedic Association score 12-14); combined approach; uppermost instrumented vertebra C3 or C4; preoperative hypermobility; and > 7 levels fused (area under the curve 0.89). A predictive model for symptomatic versus asymptomatic disease (area under the curve 0.85) included being frail, T1 slope minus cervical lordosis > 20°, and a pelvic incidence > 46.3°. Controlling for baseline deformity and disability, symptomatic patients had a greater cervical sagittal vertical axis (4-8 cm: 47.6% vs 27%) and were more malaligned according to their Scoliosis Research Society sagittal vertical axis measurement (OR 0.1) than patients without DJK at 1 year (all p < 0.05). Despite their symptomatology and higher reoperation rate, outcomes equilibrated in the symptomatic cohort at 1 year following revision. CONCLUSIONS:Overall, 32.2% of patients with CD suffered from DJK. Symptomatic DJK can be predicted with high reliability. It can be further distinguished from asymptomatic occurrences by taking into account pelvic incidence and baseline cervicothoracic deformity severity.
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    ItemOpen Access
    So Close yet So Far: The impact of undercorrection of cervical sagittal alignment during adult cervical deformity surgery - An Incremental correction analysis.
    (Journal of clinical neuroscience : official journal of the Neurosurgical Society of Australasia, 2024-10) Das, Ankita; Yung, Anthony; Onafowokan, Oluwatobi; Mir, Jamshaid; Fisher, Max R; Williamson, Tyler K; Cottrill, Ethan J; Buser, Zorica; Tretiakov, Peter S; Than, Khoi D; Shah, Neil V; Shaffrey, Christopher I; Passias, Peter G

    Background

    To compare degrees of cSVA correction and to theorize possible minimum and maximum thresholds of cSVA correction for patients to benefit clinically.

    Methods

    657 operative ACD patients in a retrospective cohort study of a prospectively enrolled database with complete baseline and two year radiographic and HRQL data were examined. Patients were grouped into an optimally corrected cohort (OC; postop cSVA ≤ 4 cm) and an undercorrected cohort (UC; postop cSVA > 4 cm) based on postoperative radiographs.

    Results

    265 patients met inclusion criteria (mean age 58.2 ± 11.4 years, BMI 28.9 ± 7.5, CCI 0.9 ± 1.3). 11.2 % of patients were UC, while 88.8 % of patients were OC. UC cohort experienced a significantly greater occurrence of radiographic complications (47.8 % v. 27.6 %, p = 0.046). UC also demonstrated a significantly greater rate of severe 6 M DJK (p < 0.001) and 1Y DJK (26.1 % v. 2.7 %, p < 0.001). In terms of HRQLs, the OC cohort demonstrated significantly greater 2Y EQ5D-Health values (76.9 v. 46.7, p = 0.012). Being UC was a significant predictor of moderate-high 1Y mJOA score (OR 3.0, CI 95 % 1.2-7.3, p = 0.015) Still, in terms of CIT, the threshold for DJF risk increased significantly (p = 0.026) when the cSVA were surgically corrected greater than 5 cm.

    Conclusion

    Undercorrection of cSVA yielded worse clinical outcomes and posed a significant risk for radiographic complications. Although undercorrection does not seem to be efficacious, surgical correction beyond certain thresholds should still be respected as there is a risk for DJK on either end of the spectrum.