Preoperative Coronal Balance Research Articles

Complications and health-related quality of life following lumbosacral hemivertebra resection and short segmental fusion: a retrospective cohort study

Previous literature has provided descriptions of postoperative complications. However, these studies have included heterogeneous cohorts of hemivertebra patients undergoing different surgical methods and addressing deformities at various locations. To assess independent risk factors for complications following lumbosacral hemivertebra (LSHV) resection and to further explored the potential association between complications and health-related quality of life (HRQOL). Retrospective cohort study. We retrospectively analyzed consecutive patients who underwent LSHV resection and short segment fusion at our institution between 2010 and 2022. In the current study, the outcome measure were complications and HRQOL. Between 2010 and 2022, a total of 64 consecutive patients with LSHV underwent hemivertebra resection. The diagnostic criteria for LSHV were delineated that the hemivertebra resides caudal to L5 and beyond. Electronic patient record and radiographic data were reviewed retrospectively in our electronic database. According to complications, the patients were divided into with and without complications, and further stratified as neurological, mechanical, and infectious complications. HRQOL outcomes were collected preoperatively, 3 months postoperatively, and at last follow-up using the Scoliosis Research Society-22 (SRS-22) questionnaire. Multivariate logistic regression models were used to determine independent risk factors affecting complications. A total of 64 patients were enrolled in this study for at least 2-year follow-up. The mean follow-up was 7.3±4.2 years. In the coronal plane, the mean main curve was corrected from 27.3° preoperatively to 8.0° postoperatively, and 9.3° at last follow-up. Global spine balance was significantly improved after surgery, and kept stable during the follow-up. In all, 18 complications were recorded in 15 (23.4%) patients. In the multivariate logistic regression model, 3 independent risk factors for complication were screened out, including age (OR=1.16, 95% CI 1.01-1.34, p=.042), anterior reconstruction (OR=3.40, 95% CI 1.03-11.2, p=.045), and preoperative CB (OR=1.06, 95% CI 1.00-1.12, p=.036). The mean SRS-22 total and domain scores for the entire cohort showed improvement at last follow-up. However, in the noncomplication group, the improvements in SRS-22 scores were more substantial. Postoperative neurological and mechanical complications are common medical events following LSHV resection. The age, anterior column reconstruction, and preoperative coronal balance were the independent risk factors. Compared to the noncomplication group, the improvements in HRQOL are blunted in the complication group.

Apical Vertebras Distribution Modifier for Coronal Balance Classification in Adult Idiopathic Scoliosis.

Background: We aimed to propose the apical vertebras distribution modifier to supplement the coronal balance (CB) classification for adult idiopathic scoliosis (AdIS). An algorithm to predict postoperative coronal compensation and avoid postoperative coronal imbalance (CIB) was proposed. Methods: Patients were categorized into CB and CIB groups according to the preoperative coronal balance distance (CBD). The apical vertebras distribution modifier was defined as negative (-) if the centers of the apical vertebras (CoAVs) were on either side of the central sacral vertical line (CSVL) and positive (+) if the CoAVs were on the same side of the CSVL. Results: A total of 80 AdIS patients, with an average age of 25.97 ± 9.20 years, who underwent posterior spinal fusion (PSF) were prospectively recruited. The mean Cobb angle of the main curve was 107.25 ± 21.11 degrees at preoperation. The mean follow-up time was 3.76 ± 1.38 (2-8) years. At postoperation and follow-up, CIB occurred in 7 (70%) and 4 (40%) CB- patients, 23 (50%) and 13 (28.26%) CB+ patients, 6 (60%) and 6 (60%) CIB- patients, and 9 (64.29%) and 10 (71.43%) CIB+ patients. Health-related quality of life (HRQoL) was significantly better in the CIB- group compared with that of the CIB+ group in the dimension of back pain. To avoid postoperative CIB, the correction rate of the main curve (CRMC) should match the compensatory curve for CB-/+ patients; the CRMC should be greater than the compensatory curve for CIB- patients; and the CRMC should be less than the compensatory curve for CIB+ patients, and the inclination of the LIV needs to be reduced. Conclusions: CB+ patients have the least postoperative CIB rate and the best coronal compensatory ability. CIB+ patients are at a high risk of postoperative CIB and have the poorest coronal compensatory capacity in the event of postoperative CIB. The proposed surgical algorithm facilitates the handling of each type of coronal alignment.

Kickstand rods and correction of coronal malalignment in patients with adult spinal deformity.

Coronal malalignment (CM) is a challenging spinal deformity to treat. The kickstand rod (KR) technique is powerful for correcting truncal shift. This study tested the hypothesis that the KR technique provides superior coronal alignment correction in adult deformity compared with traditional rod techniques. A retrospective evaluation of a prospectively collected multicenter database was performed. A 2:1 matched cohort of non-KR accessory rod and KR patients was planned based on preoperative coronal balance distance (CBD) and a vector of global shift. Patients were subgrouped according to CM classification with a 30-mm CBD threshold defining CM, and comparisons of surgical and clinical outcomes among groups was performed. Twenty-one patients with preoperative CM treated with a KR were matched to 36 controls. KR-treated patients had improved CBD compared with controls (18 vs. 35mm, P < 0.01). The postoperative CBD did not result in clinical differences between groups in patient-reported outcomes (P ≥ 0.09). Eight (38%) of 21 KR patients and 12 (33%) of 36 control patients with preoperative CM had persistent postoperative CM (P = 0.72). CM class did not significantly affect the likelihood of treatment failure (postoperative CBD > 30mm) in the KR cohort (P = 0.70), the control cohort (P = 0.35), or the overall population (P = 0.31). Application of the KR technique to coronal spinal deformity in adults allows for successful treatment of CM. Compared to traditional rod techniques, the use of KRs did not improve clinical outcome measures 1year after spinal deformity surgery but was associated with better postoperative coronal alignment.

Matching correction of main and compensatory curves is critical for immediate postoperative coronal balance in correction of severe adult idiopathic scoliosis.

To analyze the correlation between immediate postoperative coronal imbalance and the matching degree of the correction rates of the main curve and compensatory curves in the surgical treatment of severe adult idiopathic scoliosis. Patients were categorized into three types based on the preoperative coronal balance status (type A = balance, type B = shifted to cave side and type C = shifted to convex side), and each type was further divided into two subgroups based on the postoperative coronal balance status (balance and imbalance). Different coronal parameters before and after operations were calculated and compared. The rate of postoperative CIB was highest in type C patients (53.8%) and lowest in type A patients (31.5%). To avoid postoperative CIB, the value of the postoperative CRmain should fall within the range of 1.001 × CRcomp ± 2.84% in type A patients, 1.112 × CRcomp + 3.3% ± 5.02% in type B patients and 0.907 × CRcomp - 2.5% ± 4.38% in type C patients. Mismatch between the correction rates of the main curve and compensation curves is a critical cause of immediate postoperative CIB. The relatively equal correction of the main curve and compensatory curves is essential for type A patients to achieve postoperative coronal balance, while the correction rate of the main curve should be higher than the compensatory curves in type B patients and vice versa in type C patients. Three formulas for the three different types were developed to provide helpful guidance information for surgical planning.

Risk factors for postoperative coronal decompensation in adult lumbar scoliosis after posterior correction with osteotomy.

To determine potential risk factors for postoperative coronal imbalance following posterior osteotomy for adult scoliosis. A total of 74 patients underwent osteotomy for rigid adult lumbar scoliosis. A group of 20 patients with postoperative coronal imbalance was identified. Clinical data and surgical strategies were compared to determine the risk factors, including age, gender, etiology, Cobb angle, preoperative coronal balance distance, direction of preoperative imbalance, T1 tilt, tilt of upper instrumented vertebra (UIV), UIV translation, location of UIV (T6 above or below), fusion to L5 or S1, lower instrumented vertebra (LIV) tilt, LIV rotation, screw density, osteotomy procedure (PSO or SPOs) and use of iliac screws. Comparison between patients with and without postoperative coronal imbalance showed that postoperative coronal imbalance occurred in older patients and those with degenerative scoliosis as the etiology, UIV above T6, preoperative LIV rotation, preoperative LIV tilt and preoperative coronal imbalance towards the convex side and who underwent Smith-Petersen osteotomy. All seven parameters were included in the logistic regression analysis. UIV above T6 (P = 0.010), LIV rotation (P = 0.012) and preoperative coronal imbalance towards the convex side (P = 0.005) were identified as risk factors for postoperative coronal imbalance after osteotomy. Patients with preoperative coronal imbalance towards the convex side (UIV above T6) and LIV rotation were more likely to develop coronal imbalance than those without risk factors. Older patients and those with degenerative scoliosis were also at a relatively higher risk of postoperative coronal imbalance.

Short fusion with vertebrectomy during growth in congenital spinal deformity: is early surgical intervention recommended?

This was a multi-center retrospective cohort study included consecutive pediatric patients who were admitted to 8 institutions for the treatment of congenital spinal deformity from 1991 to 2012. The purpose of this study was to compare curve corrections and balances, reoperations, and complications at 2-year follow-up between those treated early vs. late. Although early intervention has been recommended, no empirical study has examined the optimal timing of short fusion among patients with congenital spinal deformity. Patients with congenital spinal deformity with formation failure undergoing vertebrectomy with short fusion (≤ 6 fusion segments) were categorized as early (surgery at ≤ 6years) and late (7-18years) fusion. Outcomes included coronal and sagittal curve corrections at immediate and 2-year evaluations; loss of curve correction from immediate to 2-year follow-up; coronal and sagittal balance at 2years; and inter-operative, major and minor short-term postoperative, and long-term postoperative complications and reoperations. Early fusion (N = 79) compared to late fusion (N = 96) was associated with greater percent curve correction at immediate (71% vs. 60%, p = 0.0046) and 2-year (63% vs. 52%, p = 0.0153) evaluations adjusting for surgeon experience and preoperative coronal balance. These associations were significant for males and those with 3-level fusions but not 4 to 6-level fusions. Early fusion compared with late fusion had more intraoperative (6% vs. 1%) and postoperative long-term complications (27% vs. 18%), as well as unplanned reoperations (13% vs. 9%). Early vs. late fusion had fewer short-term complications, both major (6% vs. 15%) and minor (6% vs. 15%). Patients who underwent early treatment achieved larger major curve correction by 10% compared to patients with late treatment when assessed at 2-year postoperative evaluation. However, early fusion should be considered with careful attention to possible increased risk of reoperations. Level III.

The application of a new intraoperative assessment method of coronal balance in surgical treatment of scoliosis

Objective To introduce a new method for assessing coronal balance in surgical treatment of scoliosis, and to explore its effectiveness in preventing postoperative coronal imbalance. Methods The data of forty-six consecutive patients, who underwent posterior surgery for spine deformity correction from January 2016 to December 2016, were retrospectively analyzed. The series included 19 males and 27 females with an average age of 28.24±21.16 years (7-76 years), and with lower instrumented vertebra (LIV) located at the level of L3 or below. Point-line method was used to evaluate coronal balance by determining whether the center of upper instrumented vertebra was located at the measuring rod passing through the centers of symphysis pubis and LIV among all patients during surgery. Preoperative, postoperative 1 week and 3 months Cobb angle, coronal balance distance (CBD), Oswestry Disability Index (ODI), Visual Analogue Scale (VAS), and Scoliosis Research Society Questionnaires-22 (SRS-22) were measured and recorded, and statistical analysis was conducted. And then, subgroup analysis was performed according to preoperative coronal imbalance classification to further evaluate the effectiveness of the new method. Results Among 46 patients in this study, the prevalence of preoperative coronal imbalance was 47.82% (22/46). Of them, ten patients were type B coronal imbalance and eleven patients were type C coronal imbalance. The prevalence of coronal imbalance at one week after operation was 17.39% (8/46), and the prevalence of coronal imbalance at final follow-up was 10.87% (5/46). The results showed that the mean main Cobb angle was 57.24°±26.51° and 14.71°±10.17° at pre-operation and immediate post-operation, respectively. The difference was statistically significant compared to preoperative value (t=13.211, P=0.000), and the average improvement rate was 73.53%±1.88%. Preoperative coronal balance distance CBD ranged from 2.76 mm to 66.73 mm, with an average of 22.54±13.97 mm; the mean CBD was 16.00±14.85 mm at immediate post-operation. The difference was statistically significant (t=3.665, P=0.001), with an average correction rate of 25.58%±52.39%. Our clinical outcome analysis showed that among 46 patients, the preoperative VAS was 8.11±0.89, and the final follow-up VAS was 4.15±0.79. There was a significant difference between pre-operation and the last follow-up (t=21.529, P=0.000). The preoperative ODI score was 49.76±5.84, and the final follow-up ODI score was 25.74±3.92. The difference was statistically significant (t=44.434, P=0.000). The preoperative SRS-22 was 10.57±2.13, and the final follow-up SRS-22 was 21.89±2.35. Compared to pre-operation, the difference was statistically significant (t=24.023, P=0.000). The subgroup analysis showed that in patients with type B coronal imbalance, the mean Cobb angle correction rate was 70.34%±6.02% at immediate post-operation, and there was a significant difference compared to pre-operation (t=5.437, P=0.000); the average CBD correction rate was 37.45%±29.03%, and significant difference was found (t=2.607, P=0.028). In type C patients, the average Cobb angle and CBD correction rate at immediate post-operation was 72.92%±3.67% and 44.79%±5.63%, respectively, and significant difference was found (t=7.319, P=0.000; t=7.545, P=0.000). Conclusion Point-line method was a simple and effective technique for intraoperative assessment of coronal balance, which could assist surgeons to objectively evaluate the result of restoration of the coronal alignment. The use of point-line method is contributed to improve clinical outcomes of spinal deformity correction surgery, and to prevent the occurrence of postoperative coronal imbalance. Key words: Scoliosis; Intervertebral disc degeneration; Spinal fusion; Treatment outcome

Midterm Results of Hemivertebrae Resection and Transpedicular Short Fusion in Patients Younger Than 5 Years: How Do Thoracolumbar and Lumbosacral Curves Compare?

Study DesignRetrospective case series with comparative analysis. ObjectiveTo analyze a consecutive cohort of very young patients operated for congenital scoliosis secondary to a single hemivertebra (HV) and compare thoracolumbar (TL) versus lumbosacral (LS) curve results. Summary of Background DataDespite the published successful results regarding early hemivertebra resection and short fusion for congenital hemivertebrae, literature lacks midterm results, especially in very young children. MethodsPatients under 5 years of age, operated by HV resection and transpedicular short fusion, with follow-up longer than 5 years, were included. Preoperative, postoperative (1-year), final radiographic parameters, and complications were recorded. Midterm results were analyzed and TL versus LS curves were compared. ResultsTwenty-three patients were included (14 TL and 9 LS HV). The mean age was 3.5 ± 1.7 years and the mean follow-up was 7.6 years (4.7–13.7). The mean preoperative Cobb angle (40.3° ± 6.7°), corrected 65% postoperatively and 50% at final follow-up. The compensatory cranial curve improved spontaneously from 25.3° ± 14.8° to 13.5° ± 12° and finally to 19.9° ± 10.7°. Preoperative coronal balance corrected postoperatively but worsened at the final follow-up. TL curves corrected more initially than LS curves (TL: −29°, 68%, vs. LS: −22°, 59%; p = .043); however, both groups lost correction at the final follow-up (TL: 4°, 56%, vs. LS: 7°, 39%; p = .186). The LS group had a larger preoperative compensatory curve, which corrected with surgery but lost more correction at the final follow-up (p = .046). Segmental kyphosis was especially corrected in the TL group (TL: −14° vs. LS: −2°, p = .018) and was maintained over time. ConclusionEarly hemivertebra resection and transpedicular short fusion allowed good coronal correction initially, which was difficult to maintain at midterm, especially at the LS junction. Sagittal plane correction was excellent in TL deformities and was maintained over time. Results were more challenging in the LS group compared with TL deformities. Guidance to avoid unwanted results is proposed. Level of EvidenceLevel III.

O 041 - Long-term outcome after hamstring lengthening in children with CP depends on preoperative hamstring length and velocity

Retrospective case series with comparative analysis.To analyze a consecutive cohort of very young patients operated for congenital scoliosis secondary to a single hemivertebra (HV) and compare thoracolumbar (TL) versus lumbosacral (LS) curve results.Despite the published successful results regarding early hemivertebra resection and short fusion for congenital hemivertebrae, literature lacks midterm results, especially in very young children.Patients under 5 years of age, operated by HV resection and transpedicular short fusion, with follow-up longer than 5 years, were included. Preoperative, postoperative (1-year), final radiographic parameters, and complications were recorded. Midterm results were analyzed and TL versus LS curves were compared.Twenty-three patients were included (14 TL and 9 LS HV). The mean age was 3.5 ± 1.7 years and the mean follow-up was 7.6 years (4.7–13.7). The mean preoperative Cobb angle (40.3° ± 6.7°), corrected 65% postoperatively and 50% at final follow-up. The compensatory cranial curve improved spontaneously from 25.3° ± 14.8° to 13.5° ± 12° and finally to 19.9° ± 10.7°. Preoperative coronal balance corrected postoperatively but worsened at the final follow-up. TL curves corrected more initially than LS curves (TL: −29°, 68%, vs. LS: −22°, 59%; p = .043); however, both groups lost correction at the final follow-up (TL: 4°, 56%, vs. LS: 7°, 39%; p = .186). The LS group had a larger preoperative compensatory curve, which corrected with surgery but lost more correction at the final follow-up (p = .046). Segmental kyphosis was especially corrected in the TL group (TL: −14° vs. LS: −2°, p = .018) and was maintained over time.Early hemivertebra resection and transpedicular short fusion allowed good coronal correction initially, which was difficult to maintain at midterm, especially at the LS junction. Sagittal plane correction was excellent in TL deformities and was maintained over time. Results were more challenging in the LS group compared with TL deformities. Guidance to avoid unwanted results is proposed.Level III.

Prevalence, Risk Factors, and Characteristics of the "Adding-On" Phenomenon in Idiopathic Scoliosis After Correction Surgery: A Systematic Review and Meta-Analysis.

A systematic review and meta-analysis. To discuss the prevalence, risk factors, and characteristics of the "adding-on" phenomenon in idiopathic scoliosis (IS). There are controversies on the prevalence and risk factors of the "adding-on" phenomenon. In addition, there is no comprehensive study to describe the characteristics of "adding-on" in IS patients. We performed a systematic online search using PubMed, EMBASE, Web of Science, the Cochrane Library, and China WeiPu Library to identify eligible studies. Effect size (ES), odds ratios (OR), and weight mean difference (WMD) with 95% confidence interval (CI) were used to evaluate the incidence, characteristics, and risk factors for "adding-on," respectively. The overall pooled prevalence of "adding-on" was 14%. Subgroup analysis showed that the prevalence of "adding-on" in Lenke 1A adolescent idiopathic scoliosis (AIS), Lenke 2 AIS, Lenke 5 AIS, and mixed AIS was 15%, 12%, 9%, and 16%, respectively. AIS patients with the "adding-on" phenomenon had smaller proximal thoracic curve (PTC), main thoracic curve (MTC), clavicle angle, T1 tilt angle and radiographic shoulder height (RSH), and larger correction of PTC. Age, Risser sign, preoperative PTC, preoperative MTC, preoperative lumbar curve (LC), preoperative coronal balance and sagittal balance, and T4 tile were identified as risk factors of "adding-on." Selection of lower instrumented vertebra (LIV) was also an important risk factor as LIV-Center Sacral Vertical Line (CSVL), LIV-end vertebra, LIV-Stable Vertebra, and LIV-Neutral vertebra, and deviation of LIV+1 was found to be significantly associated with "adding-on." Besides, postoperative MTC was also significantly different between patients with and without "adding-on." The pooled prevalence varied differently in different types of IS. Patients with "adding-on" had smaller PTC, MTC, angle, T1 tilt angle and RSH, and larger correction of PTC. Younger age, less skeletal maturity, smaller preoperative PTC, smaller preoperative MTC, smaller preoperative LC, larger preoperative coronal, sagittal imbalance, selection of LIV, and overcorrection of coronal and sagittal alignment were risk factors for "adding-on." 4.

Surgical treatment for severe and rigid scoliosis: a case-matched study between idiopathic scoliosis and syringomyelia-associated scoliosis

Background ContextTreatment guidelines for severe and rigid syringomyelia-associated scoliosis (SRSMS) are limited. Typically, surgeons apply practice guidelines for severe and rigid idiopathic scoliosis (SRIS) to treat SRSMS. No study has directly compared the results of surgical treatment between patients with SRSMS and those with SRIS. PurposeThe present study was performed to compare the outcomes of surgical correction of SRSMS and SRIS from clinical and radiographic perspectives. Study DesignThis is a retrospective, case-matched, single-center, institutional review board-approved study. Patient SampleA total of 26 patients with SRSMS or SRIS treated by an anterior and posterior vertebral column resection approach or an internal distraction approach were enrolled. Outcome MeasuresThe SRSMS and SRIS groups were compared on the following variables: fusion length, screw number, operation time, estimated blood loss, follow-up duration, different radiological parameters (including main thoracic curve, cranial compensatory curve, caudal compensatory curve, thoracic kyphosis, lumbar lordosis, thoracic apical vertebral translation, coronal balance, and sagittal vertical axis), Scoliosis Research Society (SRS)-22 scores, and complication rate. MethodsThirteen patients with SRSMS were matched with patients with SRIS on curve magnitude, the flexibility of the main curve, surgical procedure, age, and gender. All patients had a minimum of 2 years of follow-up. The radiographic parameters and demographic data from patients were evaluated before surgery, immediately after surgery, and at the latest follow-up. ResultsThe case matches were relatively ideal except one pair with the main curve in the opposite direction. There was no significant difference in fusion length, screw number, operation time, estimated blood loss, or follow-up duration between the two groups. No significant differences were found between the two groups in the main curve or caudal compensatory curve before surgery, immediately after the operation, or at the final follow-up. The correction of thoracic apical vertebral translation in the SRIS group was better than that in the SRSMS group. The SRSMS group had a larger preoperative, postoperative, and final follow-up cranial compensatory curve and a lower correction rate than did the SRIS group. There was no significant difference in preoperative coronal balance between the two groups. After surgery, the coronal balance in the SRSMS and SRIS groups averaged 24.4±13.2 mm and 12.1±7.9 mm, respectively, which was significantly different (p=.04). At the most recent follow-up, the coronal balance in the SRSMS group improved to 14.8±12.6 mm, and it was 11.8±8.6 mm in the SRIS group. No significant difference was found between the two groups (p=.56). There was no significant difference in thoracic kyphosis, lumbar lordosis, or sagittal vertical axis before surgery, immediately after the operation, or at the final follow-up. Before surgery and at the final follow-up, the two groups had similar scores on function, pain, self-image, mental health, and satisfaction. There was no significant difference in complication rates between the two groups. ConclusionsTypically, surgical correction outcomes are similar in patients with SRSMS and SRIS. Patients with SRIS tended to have a smaller cranial compensatory curve and better correction of the cranial compensatory curve and thoracic apical vertebral translation. Patients with SRSMS tended to have a higher proportion and greater amount of postoperative coronal imbalance, which may be improved during follow-up.

Onset and remodeling of coronal imbalance after selective posterior thoracic fusion for Lenke 1C and 2C adolescent idiopathic scoliosis (a pilot study)

BackgroundPostoperative coronal imbalance is a significant problem after selective thoracic fusion for primary thoracic and compensatory lumbar curves in adolescent idiopathic scoliosis (AIS). However, longitudinal studies on postoperative behavior of coronal balance are lacking. This multicenter retrospective study was conducted to analyze factors related to onset and remodeling of postoperative coronal imbalance after posterior thoracic fusion for Lenke 1C and 2C AIS.MethodsTwenty-one Lenke 1C or 2C AIS patients, who underwent posterior thoracic fusion ending at L3 or above, were included with a minimum 2-year follow-up. The mean patients’ age was 15.1 years at the time of surgery. Radiographic measurements were performed on Cobb angles of the main thoracic (MT) and thoracolumbar/lumbar (TLL) curves and coronal balance. Factors related to the onset of immediately postoperative coronal decompensation (IPCD) and postoperative coronal balance remodeling (PCBR), defined as an improvement of coronal balance during postoperative follow-up, were investigated using comparative and correlation analyses.ResultsMean Cobb angles for the MT and TLL curves were 57.3° and 42.3° preoperatively and were corrected to 22.8° and 22.5° at final follow-up, respectively. Mean preoperative coronal balance of −3.8 mm got worse to −21.2 mm postoperatively, and regained to −12.0 mm at final follow-up. Coronal decompensation was observed in two patients preoperatively, in ten patients immediately postoperatively, and in three patients at final follow-up. The preoperative coronal balance and lowest instrumented vertebra (LIV) selection relative to stable vertebra (SV) were significantly different between patients with IPCD and those without. PCBR had significantly negative correlation with immediately postoperative coronal balance.ConclusionsIPCD after posterior thoracic fusion for Lenke 1C and 2C AIS was frequent and associated with preoperative coronal balance and LIV selection. However, most patients with IPCD regained coronal balance through PCBR, which was significantly associated with immediately postoperative coronal balance. A fixation more distal to SV shifted the coronal balance further to the left postoperatively.

Assessment of Coronal Radiographic Parameters of the Spine in the Treatment of Adolescent Idiopathic Scoliosis.

To determine the most important preoperative factors that affect postoperative coronal parameters of scoliotic curves. All Adolescent Idiopathic Scoliosis (AIS) patients included in the study were classified according to Lenke and King Classification. The fusion levels were selected according to the rigidity of the existing curves (correction less than 50%), tilt of T1 and shoulders, sagittal angle of the curves and with considering stable and neutral end vertebra. The radiographic coronal parameters: shoulders tilt angle, iliolumbar angle and coronal balance were measured in all patients before, after, and in the last follow-up visit. One hundred twenty patients after mean of 25 months follow-up (18-40 months) were included in the study. Before operation, abnormal coronal balance (more than 2 cm shift) was noticed in 46 patents (38%) and in the last visit, was noted in 22 patients (18%). Multivariate regression analysis revealed a significant predictive value of the preoperative coronal balance on the last visit coronal balance (P value=0.01). Preoperative coronal balance is very important to make a balanced spine after surgery. Other parameters like Lenke classification or main thoracic overcorrection did not affect postoperative coronal decompensation.

The Surgical Overcorrection of Lenke Type 1 Deformities with Selective Fusion Segments: What Happens to the Coronal Balance?

PurposeThe aim of our study is to determine the alterations on coronal balance after overcorrection of Lenke type 1 curve, retrospectively.MethodsDatas of 34 patients (29 female, 5 male patients; mean age, 16.3±3.3 years; range, 13-24 years) surgically treated for scoliosis between 2004 and 2010 were reviewed, retrospectively. The adolescent idiopathic scoliosis patients with Lenke type 1 curve treated with only posterior pedicle screw and postoperative thoracic curves less than 10° by Cobb method on frontal plane were enrolled in this study. Mean follow-up period was 52.5±29.7 months.ResultsThe mean amount of the preoperative thoracic curves was measured as 41.2°±6.1° (range, 30°-56°). The mean amount of the early postoperative thoracic curves was measured as 6.5°±1.8° (range, 3°-9°). The mean amount of the thoracic curves was measured as 8.5°±4.6° (range, 3°-22°) during the last follow-up (p=0.01). The mean preoperative coronal balance was measured as 8.5mm(range, 1-30mm). The mean early postoperative coronal balance was measured as 3.5mm(range, 0-36 mm). The mean coronal balance was measured as 5.5mm(range, 0-38mm) during the last follow-up (p>0.05).ConclusionWe suggest that Lenke type 1B and 1C should be carefully evaluated and the fusion levels should be accurately selected in order to maintain the correction of coronal balance. We suggest that selective fusion with overcorrection in Lenke type 1A are applied to curves that can be corrected lumbar curve at the preoperative bending radiograph and curves that not have coronal decompensation and >10° distal junctional kyphosis, preoperatively.

Management of spinal cord injury-related scoliosis using pedicle screw-only constructs.

Almost all pediatric patients who incur a spinal cord injury (SCI) will develop scoliosis, and younger patients are at highest risk for curve progression requiring surgical intervention. Although the use of pedicle screws is increasing in popularity, their impact on SCI-related scoliosis has not been described. The authors retrospectively reviewed the radiographic outcomes of pedicle screw-only constructs in all patients who had undergone SCI-related scoliosis correction at a single institution. Medical records and radiographs from Shriner's Hospital for Children-Philadelphia for the period between November 2004 and February 2011 were retrospectively reviewed. Thirty-seven patients, whose mean age at the index surgery was 14.91±3.29 years, were identified. The cohort had a mean follow-up of 33.2±22.8 months. The mean preoperative coronal Cobb angle was 65.5°±25.7°, which corrected to 20.3°±14.4°, translating into a 69% correction (p<0.05). The preoperative coronal balance was 24.4±22.6 mm, with a postoperative measurement of 21.6±20.7 mm (p=1.00). Preoperative pelvic obliquity was 12.7°±8.7°, which corrected to 4.1°±3.8°, translating into a 68% correction (p<0.05). Preoperative shoulder balance, as measured by the clavicle angle, was 8.2°±8.4°, which corrected to 2.7°±3.1° (67% correction, p<0.05). Preoperatively, thoracic kyphosis measured 44.2°±23.7° and was 33.8°±11.5° postoperatively. Thoracolumbar kyphosis was 18.7°±12.1° preoperatively, reduced to 8.1°±7.7° postoperatively, and measured 26.8°±20.2° at the last follow-up (p<0.05). Preoperatively, lumbar lordosis was 35.3°±22.0°, which remained stable at 35.6°±15.0° postoperatively. Pedicle screw constructs appear to provide better correction of coronal parameters than historically reported and provide significant improvement of sagittal kyphosis as well. Although pedicle screws appear to provide good radiographic results, correlation with clinical outcomes is necessary to determine the true impact of pedicle screw constructs on SCI-related scoliosis correction.

Long-term 2- to 5-Year Clinical and Functional Outcomes of Minimally Invasive Surgery for Adult Scoliosis

A retrospective study. We assess MIS technique's clinical and functional outcomes during a 2- to 5-year period. Traditional surgical approaches for adult scoliosis are associated with significant blood loss and morbidity, in a population that is often elderly with multiple medical comorbidities. Minimally invasive surgery (MIS) represents a newer method of achieving similar long-term outcomes but considerably lower morbidity and complication rates. We reviewed 71 patients who underwent MIS correction of spinal deformity with fusion of 2 or more levels including: degenerative scoliosis (54), idiopathic scoliosis (11), and iatrogenic scoliosis (6). All underwent a combination of 3 MIS techniques: direct lateral interbody fusion (66), axial lumbar interbody fusion (34), and posterior instrumentation (67). Thirty-six patients were staged with direct lateral interbody fusion done first followed by the posterior instrumentation and fusion including axial lumbar interbody fusion done 3 days later. Mean age was 64 years (20-84 yr). Mean follow-up was 39 months (24-60 mo). Patients with 1-stage same-day surgery had a mean blood loss of 412 mL and a mean surgical time of 291 minutes. Patients with 2-stage surgery had a mean blood loss of 314 mL and surgical time of 183 minutes for direct lateral interbody fusion and 357 mL and 243 minutes, respectively for posterior instrumentation and axial lumbar interbody fusion. Mean hospital stay was 7.6 days (2-26 d). The mean preoperative Cobb angle was 24.7° (8.3°-65°), which corrected to 9.5° (0.6°-28.8°). Mean preoperative Coronal balance was 25.5 mm, which corrected to 11 mm. Mean preoperative sagittal balance was 31.7 mm and corrected to 10.7 mm. The mean preoperative lumbar apical vertebral translation was 24 mm and corrected to 12 mm. Fourteen patients had adverse events requiring intervention: 4 pseudarthrosis, 4 persistent stenosis, 1 osteomyelitis, 1 adjacent segment discitis, 1 late wound infection, 1 proximal junctional kyphosis, 1 screw prominence, 1 idiopathic cerebellar hemorrhage, and 2 wound dehiscence. A combination of 3 novel MIS techniques allows comparable correction of adult spinal deformity, with low pseudarthrosis rates, significantly improved functional outcomes, and excellent clinical and radiological improvement, but considerably lowers morbidity and complication rates at early and long-term follow-up.

Selective Thoracic Fusion in Lenke 1C Curves

Multicenter retrospective analysis of prospectively collected data. Evaluate radiographical and clinical characteristics of patients undergoing a selective thoracic fusion (STF) for Lenke 1C curves. STF of adolescent idiopathic scoliosis has been advocated for the so-called "false double major" curve (Lenke 1C/King type II). Despite these recommendations, many surgeons continue to perform nonselective fusions for this curve type. It is unknown to what extent other factors influence the surgeon's fusion-level selection. A prospective multicenter database included 264 patients with surgically treated Lenke 1C curves and were divided into 2 groups. The STF group included patients with the lowest instrumented vertebra at or cephalad to L1, whereas the nonselective fusion group included patients with the lowest instrumented vertebra at or caudal to L3. Preoperative radiographical, clinical (scoliometer), Scoliosis Appearance Questionnaire (SAQ), and Scoliosis Research Society (SRS) questionnaires were analyzed and compared. Only 138 of 264 patients (49%) underwent an STF. Sex ratio (90% vs. 86% female), average age (14.7 vs. 14.8 yr), and preoperative main thoracic Cobb angles (56.0° ± 9.9° vs. 55.3° ± 11.4°) were not significantly different (STF vs. nonselective fusion). However, the average thoracolumbar/lumbar (TL/L) preoperative Cobb angle was significantly smaller in the STF group (42.1° ± 8.6° vs. 47.0° ± 9.0°; P < 0.001), whereas the main thoracic: TL/L Cobb ratio (1.35 ± 0.20 vs. 1.18 ± 0.15; P < 0.001), apical vertebral translation, and rotation (1.82 ± 0.59 vs. 1.31 ± 0.53; P < 0.001), (1.16 vs. 0.98; P < 0.001) ratios were significantly greater in the STF group. Preoperative coronal balance, sagittal Cobb angles (including T10-L2 kyphosis) and Risser Grade were not significantly different. Preoperative TL/L scoliometer measures were significantly less in the STF group (8.1° ± 3.7° vs. 10.3° ± 5.4°; P = 0.001). On the SAQ, the STF group had less desire for an appearance change. Despite the recommendation to fuse only the structural thoracic curve in a 1C curve, only 49% of patients were treated with an STF. Those undergoing an STF had smaller TL/L Cobb angles, less TL/L clinical deformity, larger main thoracic: TL/L ratios, and less desire for an appearance change. 3.

Role of the upper and lowest instrumented vertebrae in predicting the postoperative coronal balance in Lenke 5C patients after selective posterior fusion

To investigate which pre- and postoperative radiographic parameters are significantly correlated with the immediate postoperative coronal balance (CB) in Lenke 5C AIS patients, and to identify any radiographic parameter that is correlated with the ultimate CB at a minimum follow-up of 2 years. Forty Lenke 5C AIS patients were recruited in the current study. Preoperative, immediate postoperative, and the latest follow-up radiographs were reviewed measuring various radiographic parameters related to UIV and LIV. The correlations between different parameters and CB were then studied. The average follow-up time was 35.2 months. Correlation analysis showed that the following radiographic parameters significantly associated with the immediate postoperative CB in Lenke 5C patients: preoperative CB (r = 0.66, p < 0.01), preoperative UIV translation (r = 0.61, p < 0.01), preoperative LIV tilt (r = 0.61, p < 0.01), postoperative UIV translation (r = 0.51, p < 0.05), and postoperative LIV tilt (r = 0.50, p < 0.05). At the last follow-up, only the final UIV tilt was inversely correlated with the ultimate CB (r = -0.58, p < 0.05). Seven patients presented with coronal imbalance immediately after surgery. However, only one of the seven patients presented with coronal imbalance at the last follow-up, and the other six achieved C7PL-CSVL distance within 10 mm. In Lenke 5C patients, preoperative UIV translation and LIV tilt are two important parameters that can predict the immediate postoperative CB. During the postoperative follow-up, UIV tilt may play a very important role in compensating for postoperative coronal imbalance.