Selective Fusion in Adolescent Idiopathic Scoliosis with Curves Types 1B and 1C of the Lenke Classification

Study Design: Retrospective cohort. Objective: ( a) To compare the recommendations of Lenke and Peking Union Medical College (PUMC) classifications in choosing distal fusion levels in Lenke 1 adolescent idiopathic scoliosis (AIS) curves and ( b) to analyze whether the variability in distal fusion levels influences treatment outcomes. Methods: Hospital records of Lenke 1 AIS patients operated for single stage, posterior-only deformity correction were analyzed. Distal fusion levels recommended by Lenke and PUMC classifications were calculated and were compared with the actual distal fusion levels. The study population was divided based on whether the actual distal fusion levels were in agreement, shorter or longer than those recommended by Lenke classification. Subgroup analysis of Lenke 1C curves was done. The groups were compared with regard to the following outcome measures: Cobb angle correction, postoperative sagittal vertical axis, postoperative C7 offset, and Scoliosis Research Society–22r (SRS-22r) score at 24 months. Results: The distal fusion levels recommended by the 2 classifications were in agreement in 92 of 104 cases. In all the cases with disparity, Lenke classification recommended shorter fusions than the PUMC classification. No statistically significant difference was observed in the outcome measures—whether the actual distal fusion levels were in agreement, shorter, or longer than those recommended by the Lenke classification or whether or not the recommendations for selective fusion of any of these classifications were adhered to. Conclusion: Lenke classification can save fusion levels without compromising on treatment outcomes when compared with PUMC classification. Variability in choice of distal fusion levels is not clinically significant at 24-month follow-up.

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Does Thoracic Kyphosis Have Any Importance in Selective Versus Nonselective Fusion Preference in Patients With Lenke Type 5C Adolescent Idiopathic Scoliosis? A Contribution to the Guidance of the Lenke Classification

10.21203/rs.3.rs-340655/v1 ◽

2021 ◽

Author(s):

Gökhan Karademir ◽

Kerim Sarıyılmaz ◽

Okan Özkunt ◽

Mehmet Demirel ◽

Fatih Dikici ◽

...

Keyword(s):

Adolescent Idiopathic Scoliosis ◽

Idiopathic Scoliosis ◽

Thoracic Kyphosis ◽

Sagittal Plane ◽

Treatment Preference ◽

Level Of Evidence ◽

Lenke Classification ◽

Selective Fusion ◽

The Mean ◽

Age Range

Abstract BackgroundAlthough Lenke classification analyses the sagittal plane as (+), N, and (-), it does not consider it in the choice of treatment, and it has limitations with overall thoracic kyphosis (TK). To investigate the importance of TK for treatment preference in patients with Lenke 5C adolescent idiopathic scoliosis (AIS) by comparing radiological outcomes of the patients who underwent selective fusion (SF) or nonselective fusion (NSF). MethodsThirty-two patients with Lenke type 5C AIS were included and then divided into two groups as per the fusion procedure used in the surgical treatment. SF group including 17 patients (15 females; mean age = 16 years, age range, 14–21) with normal TK and NSF group including 15 patients (11 females; mean age = 17 years, age range, 13–26) with thoracic hyper-kyphosis. Thorocolumbar/lumbar (TL/L) Cobb, thoracic (T) Cobb, TK and lumbar lordosis (LL) were measured on standing spine radiographs preoperatively and at the final follow-up. The correction rates (CR) of each radiographic parameter were calculated.ResultsNo significant differences were observed in the mean CR of all radiographic parameters, except TK and LL correction rates. The mean CR of TK was significantly higher in NSF group (-17% [range, -100–69]) than in SF group (67% [range, 9–100]) (p = 0.000). Likewise, the mean CR of LL was found significantly higher in NSF group (12.47% [range, -100–51]) than in SF group (-2.41% [range, -75–47]) (p = 0.036).ConclusionIn patients in whom Lenke's sagittal modifier is N, SF can be performed efficiently. NSF should be preferred in those with Lenke's sagittal modifiers (+) as TK can be better controlled with NSF.Level of Evidence: 3

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Clinical predictive model of lumbar curve Cobb angle below selective fusion for thoracic adolescent idiopathic scoliosis: a longitudinal multicenter descriptive study

European Journal of Orthopaedic Surgery & Traumatology ◽

10.1007/s00590-021-03054-5 ◽

2021 ◽

Author(s):

Federico Solla ◽

Walid Lakhal ◽

Christian Morin ◽

Jerome Sales de Gauzy ◽

Gaby Kreichati ◽

...

Keyword(s):

Adolescent Idiopathic Scoliosis ◽

Idiopathic Scoliosis ◽

Cobb Angle ◽

Predictive Model ◽

Descriptive Study ◽

Lumbar Curve ◽

Selective Fusion ◽

Clinical Predictive Model

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Sagittal profile modifications in hybrid versus all screw technique in adolescent idiopathic scoliosis

Scientific Reports ◽

10.1038/s41598-020-79523-4 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Laura Scaramuzzo ◽

Antonino Zagra ◽

Giuseppe Barone ◽

Stefano Muzzi ◽

Leone Minoia ◽

...

Keyword(s):

Adolescent Idiopathic Scoliosis ◽

Idiopathic Scoliosis ◽

Cobb Angle ◽

Thoracic Kyphosis ◽

Sagittal Alignment ◽

Vertical Axis ◽

Sagittal Profile ◽

Sacral Slope ◽

Sagittal Vertical Axis ◽

Lenke Classification

AbstractAim of the study was to evaluate sagittal parameters modifications, with particular interest in thoracic kyphosis, in patients affected by adolescent idiopathic scoliosis (AIS) comparing hybrid and all-screws technique. From June 2010 to September 2018, 145 patients were enrolled. Evaluation included: Lenke classification, Risser scale, coronal Cobb angle, thoracic kyphosis (TK), lumbar lordosis (LL), sagittal vertical axis (SVA), pelvic incidence (PI), pelvic tilt (PT), sacral slope (SS). Patients were divided in two groups (1 all-screws and 2 hybrid); a further division, in both groups, was done considering preoperative TK values. Descriptive and inferential statistical analysis was conducted. 99 patients were in group 1, 46 in group 2 (mean follow-up 3.7 years). Patients with a normo-kyphotic profile developed a little variation in TK (Δ pre–post = 2.4° versus − 2.0° respectively). Hyper-kyphotic subgroups had a tendency of restoring a good sagittal alignment. Hypo-kyphotic subgroups, patients treated with all-screw implants developed a higher increase in TK mean Cobb angle (Δ pre–post = 10°) than the hybrid subgroup (Δ pre–post = 5.4°) (p = 0.01). All-screws group showed better results in restoring sagittal alignment in all subgroups compared to hybrid groups, especially in hypo-TK subgroup, with the important advantage to give better correction on coronal plane.

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A Decision Tree Can Increase Accuracy When Assessing Curve Types According to Lenke Classification of Adolescent Idiopathic Scoliosis

Spine ◽

10.1097/brs.0b013e3181bf280e ◽

2010 ◽

Vol 35 (10) ◽

pp. 1054-1059 ◽

Cited By ~ 6

Author(s):

Philippe Phan ◽

Neila Mezghani ◽

Marie-Lyne Nault ◽

Carl-Éric Aubin ◽

Stefan Parent ◽

...

Keyword(s):

Adolescent Idiopathic Scoliosis ◽

Decision Tree ◽

Idiopathic Scoliosis ◽

Lenke Classification

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What happens to the unfused upper thoracic curve after posterior spinal fusion for adolescent idiopathic scoliosis?

Journal of Neurosurgery Pediatrics ◽

10.3171/2020.10.peds20671 ◽

2021 ◽

pp. 1-7

Author(s):

M. Omar Iqbal ◽

Amer F. Samdani ◽

Joshua M. Pahys ◽

Peter O. Newton ◽

Suken A. Shah ◽

...

Keyword(s):

Adolescent Idiopathic Scoliosis ◽

Idiopathic Scoliosis ◽

Univariate Analysis ◽

Posterior Spinal Fusion ◽

Research Society ◽

Curve Correction ◽

Scoliosis Research Society ◽

Lenke Classification ◽

Upper Instrumented Vertebra ◽

Upper Thoracic

OBJECTIVE Spontaneous lumbar curve correction after selective thoracic fusion in surgery for adolescent idiopathic scoliosis (AIS) is well described. However, only a few articles have described the course of the uninstrumented upper thoracic (UT) curve after fusion, and the majority involve a hybrid construct. In this study, the authors sought to determine the outcomes and associated factors of uninstrumented UT curves in patients with AIS. METHODS The authors retrospectively reviewed a prospectively collected multicenter AIS registry for all consecutive patients with Lenke type 1–4 curves with a 2-year minimum follow-up. UT curves were considered uninstrumented if the upper instrumented vertebra (UIV) did not extend above 1 level from the lower end vertebra of the UT curve. The authors defined progression as > 5°, and divided patients into two cohorts: those with improvement in the UT curve (IMP) and those without improvement in the UT curve (NO IMP). Radiographic, demographic, and Scoliosis Research Society (SRS)–22 survey outcome measures were compared using univariate analysis, and significant factors were compared using a multivariate regression model. RESULTS The study included 450 patients (370 females and 80 males). The UT curve self-corrected in 86% of patients (n = 385), there was no change in 14% (n = 65), and no patients worsened. Preoperatively, patients were similar with respect to Lenke classification (p = 0.44), age (p = 0.31), sex (p = 0.85), and Risser score (p = 0.14). The UT curves in the IMP group self-corrected from 24.7° ± 6.5° to 12.6° ± 5.9°, whereas in the NO IMP group UT curves remained the same, from 20.3° ± 5.8° to 18.5° ± 5.7°. In a multivariate analysis, preoperative main thoracic (MT) curve size (p = 0.004) and MT curve correction (p = 0.001) remained significant predictors of UT curve improvement. Greater correction of the MT curve and larger initial MT curve size were associated with greater likelihood of UT curve improvement. CONCLUSIONS Spontaneous UT curve correction occurred in the majority (86%) of unfused UT curves after MT curve correction in Lenke 1–4 curve types. The magnitude of preoperative MT curve size and postoperative MT curve correction were independent predictors of spontaneous UT curve correction.

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Predicted final spinal height in patients with adolescent idiopathic scoliosis can be achieved by surgery regardless of maturity status

The Bone & Joint Journal ◽

10.1302/0301-620x.100b10.bjj-2017-1540.r2 ◽

2018 ◽

Vol 100-B (10) ◽

pp. 1372-1376 ◽

Cited By ~ 4

Author(s):

H. Bao ◽

Z. Liu ◽

M. Bao ◽

Z. Zhu ◽

P. Yan ◽

...

Keyword(s):

Adolescent Idiopathic Scoliosis ◽

Idiopathic Scoliosis ◽

Growth Restriction ◽

Fusion Surgery ◽

Group 4 ◽

Selective Fusion ◽

Group 3 ◽

Group 2 ◽

Group 1

Aims The aim of this study was to investigate the impact of maturity status at the time of surgery on final spinal height in patients with an adolescent idiopathic scoliosis (AIS) using the spine-pelvic index (SPI). The SPI is a self-control ratio that is independent of age and maturity status. Patients and Methods The study recruited 152 female patients with a Lenke 1 AIS. The additional inclusion criteria were a thoracic Cobb angle between 45° and 70°, Risser 0 to 1 or 3 to 4 at the time of surgery, and follow-up until 18 years of age or Risser stage 5. The patients were stratified into four groups: Risser 0 to 1 and selective fusion surgery (Group 1), Risser 0 to 1 and non-selective fusion (Group 2), Risser 3 to 4 and selective fusion surgery (Group 3), and Risser 3 to 4 and non-selective fusion (Group 4). The height of spine at follow-up (HOSf) and height of pelvis at follow-up (HOPf) were measured and the predicted HOS (pHOS) was calculated as 2.22 (SPI) × HOPf. One-way analysis of variance (ANOVA) was performed for statistical analysis. Results Of the 152 patients, there were 32 patients in Group 1, 27 patients in Group 2, 48 patients in Group 3, and 45 patients in Group 4. Significantly greater HOSf was observed in Group 3 compared with Group 1 (p = 0.03) and in Group 4 compared with Group 2 (p = 0.02), with similar HOPf (p = 0.75 and p = 0.83, respectively), suggesting that patients who undergo surgery at Risser grade of 0 to 1 have a shorter spinal height at follow-up than those who have surgery at Risser 4 to 5. HOSf was similar to pHOS in both Group 1 and Group 2 (p = 0.62 and p = 0.45, respectively), indicating that undergoing surgery at Risser 0 to 1 does not necessarily affect final spinal height. Conclusion This study shows that fusion surgery at Risser 0 may result in growth restriction unlike fusion surgery at Risser 3 to 4. Despite such growth restriction, AIS patients could reach their predicted or ‘normal’ spinal height after surgery regardless of baseline maturity status due to the longer baseline spinal length in AIS patients and the remaining growth potential at the non-fusion levels. Cite this article: Bone Joint J 2018;100-B:1372–6.

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