Surgical Treatment of Lenke Type 5 Adolescent Idiopathic Scoliosis: A Systematic Review

Risk factors for proximal junctional kyphosis in a multicenter study of Lenke type 5 and 6 adolescent idiopathic scoliosis patients

PURPOSE

In Lenke type 5 and 6 curves, a major thoracolumbar or lumbar curve, the rates of PJK are reported as high as 50%. The purpose of this study was to confirm the rate of PJK, investigate possible risk factors, and evaluate surgical complications and the long-term effects of PJK on patient outcomes.

METHODS

A retrospective review of multicenter data identified 192 with patients with 2 year and 94 with 5-year follow-up. Included patients had a Lenke type 5 or 6 curve and underwent a selective thoracolumbar or lumbar curve fusion. All radiographs preoperatively and postoperatively (1 year, 2 years, and 5 years) were evaluated. Demographic and radiographic data was analyzed as risk factors for PJK using a multi-variate regression. Outcomes scores and complications were compared between groups.

RESULTS

17 patients (8.9%) developed radiographic PJK; 1 at 1 year, 7 at 2 years, and another 9 at 5 years. All 17 patients had an upper instrumented vertebra (UIV) within 3 levels or less caudal of the thoracic kyphosis apex (the most horizontal vertebra on the sagittal); no patient with a UIV 4 or more levels from the thoracic apex (n = 96) developed PJK (X2 = 13.03, p < 0.001). In addition, PJA > 8° was found to significantly increase the risk of PJK (p = 0.039). SRS scores were significantly worse for PJK patients at 5 years in the self-image and function (p < 0.01).

CONCLUSION

In Lenke 5/6 curves, no patient with a UIV 4 or more levels caudal to the thoracic kyphosis apex had PJK up to 5 years postoperatively. PJA greater than 8° was identified as a risk factor for PJK. Patients with radiographic PJK had worse SRS scores 5 years postoperatively.

Anterior fusion surgery with overcorrection in the treatment of adolescent idiopathic scoliosis with Lenke 1 AR curve type: how to achieve overcorrection and its effect on postoperative spinal alignment

BACKGROUND

The efficacy of anterior fusion with overcorrection in the instrumented vertebra for Lenke 1 AR type curves has been reported, but how to achieve overcorrection and how overcorrection affects spinal alignment are unclear. The purpose of this study was to identify the factors that cause overcorrection, and to investigate how overcorrection affects postoperative spinal alignment in the surgical treatment of Lenke 1 AR type curves.

METHODS

Patients who had anterior surgery for a Lenke type 1 or 2 and lumbar modifier AR (L4 vertebral tilt to the right) type scoliosis and minimum 2-year follow-up were included. The radiographic data were measured at preoperative, postoperative 1 month, and final follow-up. The UIV-LIV Cobb angle was determined as the Cobb angle between the upper instrumented vertebra (UIV) and the lower instrumented vertebra (LIV), and a negative number for this angle was considered overcorrection. The screw angle was determined to be the sum of the angle formed by the screw axis and the lower and upper endplates in the LIV and UIV, respectively. The change (Δ) in the parameters from postoperative to final follow-up was calculated. The relationships between the UIV-LIV Cobb angle and other radiographic parameters were evaluated by linear regression analyses.

RESULTS

Fourteen patients met the inclusion criteria. Their median age was 15.5 years, and the median follow-up period was 53.6 months. The median UIV-LIV Cobb angle was -1.4° at postoperative 1 month. The median screw angle was 4.7°, and overcorrection was achieved in 11 (79%) cases at postoperative 1 month. The screw angle (r2 = 0.42, p = 0.012) and Δ FDUV-CSVL (the deviation of the first distal uninstrumented vertebra from the central sacral vertical line, r2 = 0.53, p = 0.003) were significantly correlated with the UIV-LIV Cobb angle.

CONCLUSIONS

Screw placement in the UIV and LIV not parallel to the endplate, but angled, was an effective method to facilitate overcorrection in the instrumented vertebrae. The results of the present study suggest that overcorrection could bring spontaneous improvement of coronal balance below the instrumented segment during the postoperative period.

Influence of age and severity of Lenke 5 or 6 idiopathic scoliosis on postoperative quality of life in adult patients

INTRODUCTION

Thoracolumbar adolescent idiopathic scoliosis can continue to progress beyond skeletal maturity. Ideal timing of surgery remains undefined. Earlier intervention, with shorter instrumentation, incurs early partial loss of lumbar motion. Waiting for progression incurs a greater risk of extensive arthrodesis. The aim of the present study was to assess the quality-of-life impact of age and scoliosis severity at surgery.

MATERIAL AND METHODS

Patients with Lenke 5 or 6 adolescent idiopathic scoliosis, aged 16-45years, were analyzed based on a prospective clinical registry. Oswestry Disability Index (ODI) and Scoliosis Research Society (SRS)-22 scores were collected preoperatively and at 6months, 1year and 2years. Coronal and sagittal alignments were measured on full-spine radiographs, and curve flexibility was assessed on bending radiographs. A mixed linear model was used to assess the impact of age, Cobb angle and flexibility on quality of life.

RESULTS

Thirty-six patients were included. Mean ODI was 20.5% preoperatively and 13.8% at 2years (p=0.017). Mean SRS-22 was 3.2 preoperatively and 3.9 at 2years (p<0.001). Mean Cobb angle was 56.6° preoperatively and 23.2° at 2years (p<0.001), with mean preoperative reducibility of 68.1%. Age and ODI correlated preoperatively (r=0.6; p<0.001) and at 6months (r=0.5; p=0.002), as did age and SRS-22 (r=-0.6; p<0.001 and r=-0.6; p<0.001, respectively). Linear regression found a significant negative correlation between thoracolumbar Cobb angle and change in SRS-22 at 6months.

DISCUSSION

In 16-45 year-olds with Lenke 5 or 6 idiopathic scoliosis, age influenced SRS-22 score. Younger patients had better quality of life both pre- and post-operatively. Curve magnitude influenced postoperative score. The present study suggests that early surgical correction in younger patients, where instrumentation can be shorter, does not impair quality of life.

LEVEL OF EVIDENCE

IV; prospective registry study.

Development of Notch-Free, Pre-Bent Rod Applicable for Posterior Corrective Surgery of Thoracolumbar/Lumbar Adolescent Idiopathic Scoliosis

Adolescent idiopathic scoliosis (AIS), the most common pediatric musculoskeletal disorder, causes a three-dimensional spine deformity. Lenke type 5 AIS is defined as a structural thoracolumbar/lumbar curve with nonstructural thoracic curves. Although a rod curvature will affect clinical outcomes, intraoperative contouring of the straight rod depends on the surgeon's knowledge and experience. This study aimed to determine the optimum rod geometries to provide a pre-bent rod system for posterior spinal surgery in patients with Lenke type 5 AIS. These pre-bent rods will be beneficial for achieving proper postoperative outcomes without rod contouring based on surgeon experience. We investigated 20 rod geometries traced in posterior spinal reconstruction in patients with Lenke type 5 AIS. The differences between the center point clouds in each cluster were evaluated using the iterative closest point (ICP) method with modification. Before the evaluation using the ICP method, the point clouds were divided into four clusters based on the rod length using a hierarchical cluster analysis. Because the differences in the values derived from the ICP method were <5 mm for each length-based cluster, four representative rod shapes were generated from the length-based clusters. We identified four optimized rod shapes that will reduce operation time, leading to a decreased patient and surgeon burden.

Association Between Lenke Classification, The Extent of Lumbar Spinal Fusion, and Health-Related Quality of Life After Instrumented Spinal Fusion for Adolescent Idiopathic Scoliosis

STUDY DESIGN

Prospective cohort study.

SUMMARY OF BACKGROUND DATA

Lenke classification is used to define the curve type in adolescent idiopathic scoliosis (AIS). The association of Lenke classification and long-term postoperative health-related quality of life (HRQoL) remains unclear.

OBJECTIVE

The purpose of this study was to assess the association between Lenke classification and HRQoL in patients who underwent spinal fusion for AIS.

MATERIALS AND METHODS

In all, 146 consecutive patients (mean age 15.1 yr) operated for AIS between 2007 and 2019 with a minimum 2-year follow-up were included. Fifty-three (36%) patients reached the 10-year follow-up. Their HRQoL was assessed with the SRS-24 questionnaire preoperatively, at six months, two years, and 10 years after surgery.

RESULTS

The preoperative major curve was the largest in Lenke 3 (mean 63 ° ) and 4 (mean 62 ° ) groups and the lowest in Lenke 5 groups (mean 48 ° , P <0.05). These curves were corrected to a mean of 15 ° with no differences between groups. We found no evidence of differences between the preoperative HRQoL scores between the Lenke groups. The self-image domain of SRS-24 was lower in patients with isolated major thoracolumbar scoliosis (Lenke 5) when compared with double-thoracic (Lenke 2) group at the two-year follow-up (mean [95% CI] 3.6 [3.3-3.9] vs. 4.3 [4.1-4.6]). The postoperative satisfaction domain was lower in Lenke 5 group when compared with main thoracic (Lenke 1) group (mean [95% CI] 3.8 [3.5-4.0] vs. 4.3 [4.2-4.5]) and Lenke 2 group (mean 4.4, 95% CI 4.2-4.6) at the two-year follow-up. The mean total score of SRS-24 at the 10-year follow-up was highest in Lenke 1 group (mean 4.06, 95% CI 3.79-4.33) and lowest in Lenke 6 group (mean 2.92, 95% CI 2.22-3.61).

CONCLUSIONS

Lenke classification and especially its curve type (major thoracic vs. major thoracolumbar scoliosis) was associated with long-term health-related quality of life after instrumented spinal fusion for AIS.

How to make a more optimal surgical plan for Lenke 5 adolescent idiopathic scoliosis patients: a comparative study based on the changes of the sagittal alignment and selection of the lowest instrumented vertebra

BACKGROUND

The treatment of patients with Lenke 5 adolescent idiopathic scoliosis (AIS) is closely related to the pelvic because the spine-pelvis is an interacting whole. Besides, the choice of fusion segment is a significant issue; with the optimal choice, there will be fewer complications and restoring the pelvic morphology to some extent. This study aims to analyze the impact of changes in sagittal parameters and selection of the lowest instrumented vertebra (LIV) on spine and pelvic morphology for better surgical strategy.

METHOD

Ninety-four patients with Lenke 5 AIS who underwent selective posterior thoracolumbar/lumbar (TL/L) curve fusion were included in the study and grouped according to pelvic morphology and position of LIV. Spinopelvic parameters were measured preoperatively, postoperatively, and at the latest follow-up. The patient's preoperative and last follow-up quality of life was assessed with the MOS item short-form health survey (SF-36) and scoliosis research society 22-item (SRS-22).

RESULT

Patients being posterior pelvic tilt had the oldest mean age (P = 0.010), the smallest lumbar lordosis (LL) (P = 0.036), the smallest thoracic kyphosis (TK) (P = 0.399) as well as the smallest proximal junctional angle (PJA) while those being anterior pelvic tilt had the largest PJA. The follow-up TK significantly increased in both groups of anterior and normal pelvic tilt (P < 0.039, P < 0.006) while no significant changes were observed in the posterior pelvic tilt group. When LIV is above L4, the follow-up PJA was larger than other groups (P = 0.049, P = 0.006). When LIV is below L4, the follow-up TK and PT were larger and LL was smaller than other groups(P < 0.05). The SF-36 and SRS-22 scores were better in the LIV = L4 group than in other groups at the last follow-up (P < 0.05).

CONCLUSION

The correction of TK and LL after surgery can improve pelvic morphology. Besides, LIV is best set at L4, which will facilitate the recovery of TK, the improvement of symptoms, and the prevention of complications and pelvic deformities. Level of evidence Level III.

Risk factors and clinical impact of persistent coronal imbalance after posterior spinal fusion in thoracolumbar/lumbar idiopathic scoliosis

OBJECTIVE

Persistent coronal imbalance (PCI) can develop postoperatively. In this study, the authors aimed to clarify the risk factors and clinical impact of PCI after posterior spinal fusion (PSF) in idiopathic scoliosis (IS) patients with a major thoracolumbar/lumbar (TL/L) curve.

METHODS

Data on 108 patients with Lenke type 5C or 6C IS who underwent PSF with a minimum of 2 years of follow-up were retrospectively analyzed. PCI was defined as coronal imbalance persisting 2 years after surgery. Radiographic parameters and clinical outcomes were compared between the PCI (+) and PCI (-) groups. Multivariate regression analyses of associated factors were performed to determine the risk factors for PCI.

RESULTS

Of the 108 patients, 48 (44%) had immediate postoperative coronal imbalance, and 10 of these patients (9%) had coronal imbalance persisting 2 years after surgery. The PCI (+) group had significantly worse postoperative subtotal and satisfaction scores than the PCI (-) group. Preoperative apical vertebral translation (AVT) of the TL/L curve (AVT-TL/L) and postoperative coronal balance (CB) were identified as independent risk factors for PCI. The cutoff values of preoperative AVT-TL/L at 49.5 mm (area under the curve [AUC] 0.835, p = 0.001, 95% CI 0.728-0.941, sensitivity 70.0%, specificity 72.4%) and those of postoperative CB at -27.5 mm (AUC 0.837, p < 0.001, 95% CI 0.729-0.945, sensitivity 78.6%, specificity 70.0%) were used to predict PCI. In selective fusion cases, older age (OR 2.110, 95% CI 1.159-3.842, p = 0.015), greater preoperative AVT-TL/L (OR 1.199, 95% CI 1.029-1.398, p = 0.020), and less postoperative CB (OR 0.855, 95% CI 0.743-0.983, p = 0.027) were independent risk factors for PCI.

CONCLUSIONS

Preoperative AVT-TL/L and postoperative CB are important parameters for predicting PCI. PCI adversely affects postoperative clinical outcomes. In selective fusion surgery, PCI tends to occur in older patients due to reduced flexibility and compensatory abilities.

Long-Term Follow-up of Posterior Selective Thoracolumbar/Lumbar Fusion in Patients With Lenke 5C Adolescent Idiopathic Scoliosis: An Analysis of 10-Year Outcomes

STUDY DESIGN

Retrospective study.

OBJECTIVE

The aim of this study was to assess long-term radiographic and clinical outcomes in Lenke 5C adolescent idiopathic scoliosis (AIS) patients after posterior selective fusion.

METHODS

Lenke 5C AIS patients who underwent posterior selective thoracolumbar/lumbar (TL/L) fusion in our hospital from January 2007 to January 2010 were recruited. Radiographic parameters were measured preoperatively and at the 3-month, 1-year, 2-year, 5-year, and 10-year follow-ups. The SRS-22 (Scoliosis Research Society) questionnaire was used to assess the clinical outcomes.

RESULTS

We included 37 patients who underwent posterior selective TL/L fusion surgery in our study, and the mean follow-up time was 11.26 ± 0.85 years. The average preoperative Cobb angles of the thoracic and TL/L curves were 24.0 ± 9.0° and 45.4 ± 6.3°, respectively, which were corrected to 12.2° and 12.4° at the 3-month follow-up postoperatively, with correction losses of 2.2° and 1.5° at the 10-year follow-up. In the sagittal plane, the degree of thoracic kyphosis (TK) gradually increased over the follow-up period. The proximal junctional angle (PJA) also gradually increased from 6.7 ± 4.6 to 13.7 ± 5.6 during the follow-up period. For the clinical outcomes, correction surgery improved the SRS-22 scores in each domain, especially in the self-image domain.

CONCLUSIONS

Posterior selective TL/L fusion can effectively correct spinal deformities, leading to stable outcomes for 10 years postoperatively. During the follow-up period, the degree of TK presented an increasing trend that remained almost constant after the 1-year follow-up. Moreover, the variation in the PJA was highly significant in the postoperative period, and it showed an increasing trend until the 2-year follow-up.

Anterior versus posterior spinal fusion for Lenke type 5 adolescent idiopathic scoliosis: a systematic review and meta-analysis of comparative studies

PURPOSE

To review and compare clinical and radiologic outcomes between anterior spinal fusion (ASF) and posterior spinal fusion (PSF) for the treatment of Lenke type 5 adolescent idiopathic scoliosis (AIS).

METHODS

A systematic review was performed according to Preferred reporting Items for Systematic Reviews and Meta-analysis (PRISMA) guidelines. All level I-III evidence studies investigating the clinical and radiologic outcomes of ASF and PSF for the treatment of Lenke type 5 AIS were included.

RESULTS

Nine studies (285 ASF patients, 298 PSF patients) were included. ASF was associated with a significantly lower number of levels fused compared with PSF (p < 0.01) with similar immediate and long-term coronal deformity correction (p = 0.16; p = 0.12, respectively). PSF achieved a better correction of thoracic hypokyphosis in one study and lumbar hypolordosis in three studies. PSF was associated with a significant shorter length of stay (LOS) compared with ASF (p < 0.01). One long-term study demonstrated a significantly higher rate of proximal junctional kyphosis (PJK) with PSF compared with ASF. There were no significant differences in major complication or re-operation rates.

CONCLUSION

For the treatment of Lenke type 5 AIS, there is moderate evidence to suggest that ASF requires a lower number of instrumented levels to achieve similar immediate and long-term coronal deformity correction compared with PSF. There is some evidence to suggest that PSF may achieve better thoracic and lumbar sagittal deformity correction compared with ASF. There is some evidence to suggest a higher incidence of PJK at long-term follow-up with PSF compared with ASF. ASF is associated with a longer post-operative LOS compared with PSF.

Is there an indication for surgery in patients with spinal deformities? - A critical appraisal

Background

High-quality evidence exists to support physiotherapy and brace treatment for scoliosis and other spinal deformities. However, according to previous systematic reviews, it seems that no evidence exists for surgery. Nevertheless, the number of research articles focussing on spinal surgery highly exceeds the number of articles focussing on conservative treatment.

Objective

The purpose of this study is to conduct an updated search for systematic reviews providing high-quality evidence for spinal surgery in patients with spinal deformities.

Method

A narrative review including PubMed and the Cochrane database was conducted on April 12, 2020, with the following search terms: (1) spinal deformities, surgery, systematic review and outcome; (2) kyphosis, surgery, systematic review and outcome; (3) Scheuermann's disease, surgery, systematic review and outcome, and (4) scoliosis, surgery, systematic review and outcome.

Results

No reviews containing prospective controlled or randomised controlled studies were found providing evidence for surgery.

Conclusions

A general indication for spine surgery just based on the Cobb angle is not given. In view of the long-term unknown variables and the possible long-term complications of such treatment, a surgical indication for patients with spinal deformities must be reviewed on an individual basis and considered carefully. A current systematic review appears necessary in order to be able to draw final conclusions on the indication for surgery in patients with spinal deformities.

Clinical implications

In view of the increasing number of surgeons with an affiliation to industry, the indication for surgery needs to be given by independent conservative specialists for spinal deformities in order to provide an objective recommendation.

Indications for Lumbar Fusion in the Skeletally Mature Adolescent: How to Address Oblique Takeoff and Limb Length Discrepancy

BACKGROUND

Indications for posterior spinal fusion (PSF) with segmental spinal instrumentation (SSI) of a scoliotic deformity in a skeletally mature individual are based on the balance between the anticipated benefit of stopping future curve progression and the potential downside of loss of spinal mobility. The dilemma regarding PSF with SSI in the adolescent population is exacerbated by the patient's participation in athletics requiring flexibility and motion of the spine, the location of the curve, the presence of pelvic obliquity, and the impact of a limb length discrepancy. The purpose of this review is to discuss the potential advantages and disadvantages of PSF with SSI in a hypothetical skeletally mature adolescent with a 45-degree lumbar curve, pelvic obliquity, and limb length discrepancy.

DISCUSSION

Natural history studies of untreated adolescent idiopathic scoliosis (AIS) have shown that slow curve progression throughout adulthood is likely. Adults with untreated AIS may also have more back pain and dissatisfaction with their appearance. Although the clinical and radiographic outcomes of PSF with SSI are excellent, patients should be counseled about the impact of fusing the lumbar spine on back pain, decreased spinal mobility, and potential inability to return to athletics at the same level. Adults who undergo surgery for AIS have greater operative morbidity and number of levels fused compared with adolescents.

CONCLUSION

These factors should be presented when discussing observation versus PSF with SSI with patients and families. Delaying surgery until formal athletic participation is complete should be considered.

C-Arm-Free Anterior Correction for Adolescent Idiopathic Scoliosis (Lenke Type 5C): Analysis of Early Outcomes and Complications

BACKGROUND

Computer-assisted spinal surgery as a technique for reducing radiation exposure to the operating staff and the complications of spinal deformity are receiving considerable attention. However, no technical reports have described the technique for navigating anterior correction of adolescent idiopathic scoliosis without C-arm fluoroscopy. The purpose of this study was to evaluate the efficacy and safety of this new C-arm-free anterior correction for scoliosis.

METHODS

This study investigated 38 consecutive patients with Lenke type 5C curves who underwent selective lumbar or thoracolumbar fusion, comprising 26 patients with conventional anterior correction surgery, and 12 patients with C-arm-free navigation surgery. The 2 groups were evaluated immediately postoperatively and at the 2-year follow-up.

RESULTS

No vascular injuries, screw malpositioning, or major complications were associated with the surgical procedure in either group. Correction rates of the lumbar curve were satisfactory with no significant difference between groups (mean, 82.6% ± 5.7% vs. 80.7% ± 10.2%, respectively). However, mean time for fluoroscopy in group C was 133 ± 9.5 seconds (P < 0.0001). No significant differences in intraoperative blood loss (642 ± 123 mL vs. 731 ± 222 mL, respectively) or surgical time (251 ± 13 min vs. 301 ± 38 min, respectively) were seen between groups. Mean final follow-up Scoliosis Research Society Outcomes Questionnaire (SRS-22) was also excellent for both group C (4.2 ± 0.19) and group N (4.3 ± 0.20).

CONCLUSIONS

C-arm-free anterior correction offers safe, effective surgery for adolescent idiopathic scoliosis. The advantage of this new technique is no radiation exposure for medical staff at centers performing large numbers of spinal procedures.

Comparative Study of the Spinopelvic Alignment in Patients With Idiopathic Lumbar Scoliosis Between Adulthood and Adolescence

BACKGROUND

Understanding the natural history of the spinopelvic alignment in adolescent idiopathic scoliosis (AIS) is important in developing surgical strategies for patients with adult idiopathic lumbar scoliosis (AdLS). Because it is challenging to follow individuals without any treatments, we sought to estimate its natural history by comparing radiographic characteristics of patients with AIS and AdLS.

METHODS

We included patients with Lenke 5 AIS and patients with AdLS who were diagnosed with Lenke 5 AIS in adolescence. The Cobb angle of the curve and spinopelvic parameters were measured by whole spine radiographs. The AdLS patients were divided into 2 groups according to age <50 years (AdLS<50) or ≥50 years (AdLS≥50). Radiographic parameters were compared among the AIS, AdLS<50, and AdLS≥50 groups. The relationship between age and each parameter was analyzed using nonlinear regression analysis.

RESULTS

We analyzed 40 patients with AIS (all female, mean age 16.8 ± 3.2 years) and 35 patients with AdLS (34 female and 1 male, mean age 55.4 ± 12.1 years). Thoracolumbar/lumbar curve and thoracolumbar kyphosis was significantly greater in the AdLS<50 group compared with the AIS group, without progression after age 50 years. Lumbar lordosis and pelvic tilt deteriorated linearly with age. AIS and AdLS<50 patients maintained sagittal balance, which deteriorated in AdLS≥50 patients.

CONCLUSIONS

Our results may predict the following natural course of Lenke 5 AIS: (1) progression of scoliotic deformity of thoracolumbar/lumbar curve with increased thoracolumbar kyphosis; (2) subsequent lumbar hypolordosis followed by pelvic retroversion; and (3) sagittal imbalance after failure of compensation.

Assessing the unique characteristics associated with surgical treatment of dystrophic lumbar scoliosis secondary to neurofibromatosis type 1: a single-center experience of more than 10 years

OBJECTIVE

Dystrophic lumbar scoliosis secondary to neurofibromatosis type 1 (DLS-NF1) may present an atypical, unique curve pattern associated with a high incidence of coronal imbalance and regional kyphosis. Early surgical intervention is complicated and risky but necessary. The present study aimed to assess the unique characteristics associated with the surgical treatment of DLS-NF1.

METHODS

Thirty-nine consecutive patients with DLS-NF1 treated surgically at a mean age of 14.4 ± 3.9 years were retrospectively reviewed. Patients were stratified into three types according to the coronal balance classification: type A (C7 translation < 30 mm), 22 patients; type B (concave C7 translation ≥ 30 mm), 0 patients; and type C (convex C7 translation ≥ 30 mm), 17 patients. Types B and C were considered to be coronal imbalance. The diversity of surgical strategies, the outcomes, and the related complications were analyzed.

RESULTS

The posterior-only approach accounted for 79.5% in total; the remaining 20.5% of patients received either additional anterior supplemental bone grafting (12.8%) to strengthen the fixation or convex growth arrest (7.7%) to reduce growth asymmetry. The lower instrumented vertebra (LIV) being L5 accounted for the largest share (41%), followed by L4 and above (35.9%), the sacrum (15.4%), and the pelvis (7.7%). Type C coronal imbalance was found in 23 patients (59%) postoperatively, and the incidence was significantly higher in the preoperative type C group (14/17 type C vs 9/22 type A, p = 0.020). All the patients with postoperative coronal imbalance showed ameliorative transition to type A at the last visit. The rate of screw malposition was 30.5%, including 9.9% breached medially and 20.6% breached laterally, although no serious neurological impairment occurred. The incidence of rod breakage was 16.1% (5/31) and 0% in patients with the posterior-only and combined approaches, respectively. Four revisions with satellite rods and 1 revision with removal of iliac screw for penetration into the hip joint were performed.

CONCLUSIONS

Surgical strategies for DLS-NF1 were diverse across a range of arthrodesis and surgical approaches, being crucially determined by the location and the severity of dystrophic changes. The LIV being L5 or lower involving the lumbosacral region and pelvis was not rare. Additional posterior satellite rods or supplementary anterior fusion is necessary in cases with insufficient apical screw density. Despite a high incidence of postoperative coronal imbalance, improvement of coronal balance was frequently confirmed during follow-up. Neurological impairment was scarce despite the higher rate of screw malposition.

Critically Low Confidence in the Results Produced by Spine Surgery Systematic Reviews: An AMSTAR-2 Evaluation From 4 Spine Journals

STUDY DESIGN

A systematic cross-sectional survey of systematic reviews (SRs).

OBJECTIVE

To evaluate the methodological quality of spine surgery SRs published in 2018 using the updated AMSTAR 2 critical appraisal instrument.

METHODS

We identified the PubMed indexed journals devoted to spine surgery research in 2018. All SRs of spine surgical interventions from those journals were critically appraised for quality independently by 2 reviewers using the AMSTAR 2 instrument. We calculated the percentage of SRs achieving a positive response for each AMSTAR 2 domain item and assessed the levels of confidence in the results of each SR.

RESULTS

We identified 28 SRs from 4 journals that met our criteria for inclusion. Only 49.5% of the AMSTAR 2 domain items satisfied the AMSTAR 2 criteria. Critical domain items were satisfied less often (39.1%) compared with noncritical domain items (57.3%). Domain items most poorly reported include accounting for individual study risk of bias when interpreting results (14%), list and justification of excluded articles (18%), and an a priori establishment of methods prior to the review or registered protocol (18%). The overall confidence in the results was rated "low" in 2 SRs and "critically low" in 26.

CONCLUSIONS

The credibility of a SR and its value to clinicians and policy makers are dependent on its methodological quality. This appraisal found significant methodological limitations in several critical domains, such that the confidence in the findings of these reviews is "critically low."

INTRA- AND INTEROBSERVER ANALYSIS OF PEDICLE SCREW PLACEMENT IN SCOLIOSIS CORRECTION

ABSTRACT Objective To establish the statistical interobserver and intraobserver concordance of thoracic pedicle screw placement in scoliosis surgery, with a 4-week interval between the two analyses. Methods Of 55 patients that evaluated the intra- and interobserver concordances of the screw positions (according to the Abul-Kasim classification) using the Kappa coefficient. Results The intraobserver concordance ranged from a Kappa coefficient of 0.516 to 0.889 (“moderate” to “almost perfect”) between the two analyses performed four weeks apart. Interobserver concordance ranged from 0.379 to 0.633 (“reasonable” to “strong”). Conclusion The intraobserver concordance was always greater than the interobserver concordance. No concordance coefficient was classified as “insignificant” or “weak”. Level of Evidence III; Retrospective study.

Anterior instrumented fusion for adolescent idiopathic scoliosis

Adolescent idiopathic scoliosis (AIS) is a complex three-dimensional deformity of the spine consisting of a lateral curvature, apical vertebral rotation, and an impairment of the sagittal profile. Surgical options include anterior and posterior approaches. Anterior instrumented fusion is suitable in Lenke type 1 and 5 curves. It supplies excellent results in coronal plane correction and is superior in the restoration of the sagittal profile and apical derotation. Fusion is shorter compared to posterior correction, and the complication rate is low. Pulmonary function is impaired postoperatively but recovers within a few years.