Anterior thoracoscopic surgery followed by posterior instrumentation and fusion in spinal deformity

Severe persistent coronal imbalance following instrumented posterior spinal fusion for adolescent idiopathic scoliosis

STUDY DESIGN

Retrospective case-control study.

OBJECTIVE

The aim of this study was to identify the risk factors and health-related quality of life (HRQoL) impact of severe (> 4 cm) post-operative coronal imbalance at 2 years following posterior spinal fusion (PSF) for adolescent idiopathic scoliosis (AIS). Coronal imbalance is an unfavorable outcome following PSF for AIS, though the degree of imbalance in such patients is typically mild. We hypothesize that a small number of patients become and remain severely imbalanced post-operatively, though this phenomenon has not been well studied.

METHODS

Prospectively collected data from a large multicenter registry were reviewed. Patients with severe coronal imbalance (SCIB; > 4 cm) 2 years after PSF were included. Matched controls without SCIB at 2 years were included at a 3:1 ratio. Comparisons were made between demographics, pre-operative radiographic measures, surgical factors, residual post-operative radiographic measures, and 2-year SRS-22 scores.

RESULTS

Nine of 954 (0.9%) patients (88.9% females; mean age 14.8 ± 2.3 years) were found to be severely imbalanced at 2 years. These patients had significantly greater pre-operative bending thoracic curve magnitude (45° vs. 33°; p = 0.013), curve flexibility (22.9% vs. 63.3%; p = 0.004), and kyphosis (41° vs. 26.5°; p = 0.034) compared to matched controls. Pre-operative curve flexibility of < 20% was associated with a 23.8 times greater odds of SCIB (95% CI 2.1-250; p = 0.008). With respect to HRQoL, median SRS-22 pain (4.1 vs. 4.8; p = 0.041), self-image (3.9 vs. 4.6; p = 0.013), general function (4.5 vs. 5; p = 0.022), and total (4.1 vs. 4.7; p = 0.012) scores at 2 years were significantly lower in cases compared to controls.

CONCLUSIONS

In the present study, thoracic curve stiffness was a strong risk factor for severe post-operative coronal imbalance, which was associated with poor HRQoL measures. Increased pre-operative thoracic curve stiffness (< 20% flexibility) should raise surgeon awareness for altering surgical approach to minimize the risk of severe post-operative coronal imbalance.

LEVEL OF EVIDENCE

Level III.

Is Anterior Release Obsolete or Does It Play a Role in Contemporary Adolescent Idiopathic Scoliosis Surgery? A Matched Pair Analysis

STUDY DESIGN

A retrospective analysis of a prospectively collected database was performed.

OBJECTIVE

The purpose of this study is to compare 3-dimensional correction associated with the anterior release (AR) and contemporary posterior instrumentation versus posterior-only surgery.

SUMMARY OF BACKGROUND DATA

The role of AR as a tool in the treatment of adolescent idiopathic scoliosis (AIS) has seen a decline with the popularization of thoracic pedicle screw instrumentation.

METHODS

Five surgeons were queried for all surgical thoracic AIS cases from 2003 to 2010 treated with thoracoscopic AR/fusion and contemporary posterior instrumentation and fusion and thoracic pedicle screw instrumentation (>80% screws) with 2-year follow-up. These cases were then matched with posterior spinal fusion only cases from a multicenter prospective database. The 2 groups were matched on the basis of major curve magnitude within 5 degrees, T5-T12 kyphosis within 9 degrees, and angle of trunk rotation within 9 degrees. Radiographic and clinical parameters were compared for the 2 groups. Continuous variables were analyzed with analysis of variance and categorical dependent variables with the χ test.

RESULTS

A total of 47 cases of AR were matched to 47 (1:1 match) posterior spinal fusion cases. Preoperative parameters were similar between groups (P>0.05). Postoperatively, AR cases had a lower major curve (20 vs. 25 degrees, P=0.034; 72% vs. 66% correction, P=0.037). T5-T12 kyphosis was greater in the AR cases (26 vs. 20 degrees; P=0.005). The angle of trunk rotation was similar for the groups. Anchor density was lower in the AR group (1.6 vs. 1.9; P<0.0001). There were 3 complications associated with the AR: 1 pneumothorax and 2 conversions to minithoracotomies for failure to maintain single lung ventilation.

CONCLUSIONS

AR improves coronal and sagittal plane correction in contemporary AIS surgery with a satisfactory complication profile with less pedicle screw density required for clinically similar corrections. A further prospective study on the benefits of AR may help define specific indications.

The Adolescent Idiopathic Scoliosis International Disease Severity Study: Do Operative Curve Magnitude and Complications Vary by Country?

BACKGROUND

The prevalence of adolescent idiopathic scoliosis (AIS) in diverse regions of the world has been studied. Access to care varies widely, and differences in disease severity and operative treatment outcomes are not well understood. This study aimed to determine variation in disease presentation and operative complications for AIS patients from an international cohort.

METHODS

This is a retrospective study carried out at seven surgical centers in the United States (Manhattan and Miami), Ghana, Pakistan, Spain, Egypt, and China. A total of 541 consecutive patients with AIS were evaluated. Preoperative major curve magnitude, operative parameters, and complications were compared among sites using analysis of variance with post hoc tests and Pearson correlation coefficients. Univariate and multivariate forward stepwise binary logistic regressions determined the variables most predictive of complications.

RESULTS

Countries with lowest-access to care (Ghana, Egypt, and Pakistan) displayed larger curves, more levels fused, longer operative time (OT), and greater estimated blood loss (EBL) than the other countries (p ≤ .001). Increasing curve magnitude was correlated with greater levels fused, longer OT, and greater EBL in all groups (p = .01). In the univariate regression analysis, Cobb magnitude, levels fused, EBL, and OT were associated with complication occurrence. Only OT remained significantly associated with complication occurrence after adjusting for Cobb magnitude, levels fused, and site (odds ratio [OR] = 1.005, 95% confidence interval 1.001-1.007, p = .003). Complications were greatest in Pakistan and Ghana (21.7% and 13.5%, respectively) and lowest in Miami (6.5%).

CONCLUSIONS

Larger curve magnitudes in the least-access countries correlated with more levels fused, longer OT, and greater EBL, indicating that increased curve magnitude at surgery could explain the difference in operative morbidity between low- and high-access countries. With OT as the prevailing predictive factor of complications, we suggest that increased curve magnitude leads to longer OTs and more complications. A lack of access to orthopedic care may be the largest contributor to the postponement of treatment.

LEVEL OF EVIDENCE

Level II.

Comparative Analysis of Combined (First Anterior, Then Posterior) Versus Only Posterior Approach for Treating Severe Scoliosis: A Mean Follow Up of 8.5 Years

STUDY DESIGN

A retrospective, one center, institutional review board approved study.

OBJECTIVE

Two methods of operative treatments were compared in order to evaluate whether a two-stage approach is justified for correction of bigger idiopathic scoliosis curves. Two stage surgery, combined anterior approach in first operation and posterior instrumentation and correction in the second operation. One stage surgery included only posterior instrumentation and correction.

SUMMARY OF BACKGROUND DATA

Studies comparing two-stage approach and only posterior approach are rather scarce, with shorter follow up and lack of clinical data.

METHODS

Three hundred forty eight patients with idiopathic scoliosis were operated using Cotrel-Dubousset (CD) hybrid instrumentation with pedicle screw and hooks. Only patients with curvatures more than or equal to 61° were analyzed and divided in two groups: two stage surgery (N = 30) and one stage surgery (N = 46). The radiographic parameters as well as duration of operation, hospitalization time, and number of segments included in fusion and clinical outcome were analyzed.

RESULTS

No statistically significant difference was observed in correction between two-stage group (average correction 69%) and only posterior approach group (average correction 66%). However, there were statistically significant differences regarding hospitalization time, duration of the surgery, and the number of instrumented segments.

CONCLUSION

Two-stage surgery has only a limited advantage in terms of postoperative correction angle compared with the posterior approach. Posterior instrumentation and correction is satisfactory, especially taking into account that the patient is subjected to only one surgery.

LEVEL OF EVIDENCE

3.

Posterior-only surgery with preoperative skeletal traction for management of severe scoliosis

PURPOSE

The surgical treatment of severe adolescent spinal deformities is challenging and carries substantial risks of mortality and morbidity. To mitigate this risk, surgeons have employed various methods as this study designed to evaluate the safety and effectiveness of preoperative halo-femoral or halo gravity traction (HGT) followed by posterior-only surgery in the management of severe scoliosis.

METHOD

A total number of 23 patients with severe scoliosis treated by preoperative skeletal traction (halo gravity or halo femoral) followed by posterior fusion and instrumentation in one stage. All patients were followed for a minimum of 2 years after surgery.

RESULTS

The average age of the patients was 12.7 years at the time of surgery. Mean of the Cobb angle improved from 99.9° ± 8.2° preoperatively to 75.3° ± 8° post-traction and 49.5° ± 7.7° postoperatively. Kyphosis angle corrected from 56.4° ± 9.5° to 38.6° ± 5.8°. The preop-FVC% was 41 ± 6.1% and after 1 year follow-up FVC% was 45.7 ± 7.7%. No patients required an anterior release due to amount of their deformity.

DISCUSSION

Despite the benefits of modern instrumentation procedures, the treatment of severe scoliosis can be very competing. We think that by applying preoperative halo femoral traction and halo-gravity traction, managing severe scoliosis will be in safe and easy manner and can lead to better deformity correction and less neurological complications and facilitate to avoid anterior operation for severe scoliosis and its related complications.

Spinal fusion for pediatric neuromuscular scoliosis: national trends, complications, and in-hospital outcomes

OBJECTIVE The objective of this study was to determine if the recent changes in technology, surgical techniques, and surgical literature have influenced practice trends in spinal fusion surgery for pediatric neuromuscular scoliosis (NMS). In this study the authors analyzed recent trends in the surgical management of NMS and investigated the effect of various patient and surgical factors on in-hospital complications, outcomes, and costs, using the Nationwide Inpatient Sample (NIS) database. METHODS The NIS was queried from 2002 to 2011 using International Classification of Diseases, Ninth Edition, Clinical Modification codes to identify pediatric cases (age < 18 years) of spinal fusion for NMS. Several patient, surgical, and short-term outcome factors were included in the analyses. Trend analyses of these factors were conducted. Both univariate and multivariable analyses were used to determine the effect of the various patient and surgical factors on short-term outcomes. RESULTS Between 2002 and 2011, a total of 2154 NMS fusion cases were identified, and the volume of spinal fusion procedures increased 93% from 148 in 2002 to 286 in 2011 (p < 0.0001). The mean patient age was 12.8 ± 3.10 years, and 45.6% of the study population was female. The overall complication rate was 40.1% and the respiratory complication rate was 28.2%. From 2002 to 2011, upward trends (p < 0.0001) were demonstrated in Medicaid insurance status (36.5% to 52.8%), presence of ≥ 1 comorbidity (40.2% to 52.1%), and blood transfusions (25.2% to 57.3%). Utilization of posterior-only fusions (PSFs) increased from 66.2% to 90.2% (p < 0.0001) while combined anterior release/fusions and PSF (AR/PSF) decreased from 33.8% to 9.8% (< 0.0001). Intraoperative neurophysiological monitoring (IONM) underwent increasing utilization from 2009 to 2011 (15.5% to 20.3%, p < 0.0001). The use/harvest of autograft underwent a significant upward trend between 2002 and 2011 (31.3% to 59.8%, p < 0.0001). In univariate analysis, IONM use was associated with decreased complications (40.7% to 33.1%, p = 0.049) and length of stay (LOS; 9.21 to 6.70 days, p <0.0001). Inflation-adjusted mean hospital costs increased nearly 75% from 2002 to 2011 ($36,805 to $65,244, p < 0.0001). In the multivariable analysis, nonwhite race, highest quartile of median household income, greater preexisting comorbidity, long-segment fusions, and use of blood transfusions were found to increase the likelihood of complication occurrence (all p < 0.05). In further multivariable analysis, independent predictors of prolonged LOS included older age, increased preexisting comorbidity, the AR/PSF approach, and long-segment fusions (all p < 0.05). Lastly, the likelihood of increased hospital costs (at or above the 90th percentile for LOS, 14 days) was increased by older age, female sex, Medicaid insurance status, highest quartile of median household income, AR/PSF approach, long-segment fusion, and blood transfusion (all p < 0.05). In multivariable analysis, the use of autograft was associated with a lower likelihood of complication occurrence and prolonged LOS (both p < 0.05). CONCLUSIONS Increasing use of IONM and posterior-only approaches may combat the high complication rates in NMS. The trends of increasing comorbidities, blood transfusions, and total costs in spinal fusion surgery for pediatric NMS may indicate an increasingly aggressive approach to these cases.

Treatment for severe idiopathic upper thoracic scoliosis in adolescence

STUDY DESIGN

To review the study of severe upper thoracic scoliosis (>90 degrees) in adolescence treated with pedicle screw constructs.

OBJECTIVE

The purpose of the present study was to analyze the treatment for upper thoracic scoliosis in adolescence.

SUMMARY OF BACKGROUND DATA

Upper thoracic scoliosis is an uncommon spinal deformity in young children. Upper thoracic scoliosis is special.

METHODS

There were 21 patients (11 boys and 10 girls) with severe upper thoracic scoliosis and their mean age was 15 years (range, 13-18 y). The mean Cobb angle was 102.2 degrees (90-118 degrees) The clavicle angle ranged from 18 to 23 degrees, with an average of 21 degrees. Patients with the major curve of scoliosis located in the upper thoracic spine were treated with a posterior spinal fusion with a pedicle screw-only construct. There was a minimum 2-year follow-up. Follow-up information was obtained clinically and radiologically.

RESULTS

All patients underwent a posterior spinal fusion with a pedicle screw-only construct. Their shoulders were nearly balanced. The preoperative major curve was 102.2±8.9 degrees with a flexibility of 25.8%±8.1% in a side-bending film. The deformity was corrected to 29.7±5.9 and 32.1±5.6 degrees at the most recent follow-up. There was a 3.9-degree correction loss during the postoperative follow-up. There were no neurological or vascular complications at 2 years of follow-up. There was no crankshaft phenomenon.

CONCLUSIONS

The pedicle screw constructs can be safely used for severe upper thoracic scoliosis. Curve correction is powerful for these curves, which are stiff and difficult to manage. Screw accuracy was excellent in this review.

Comparative analysis of perioperative differences between hybrid versus pedicle screw instrumentation in adolescent idiopathic scoliosis

STUDY DESIGN

Retrospective review of patients with adolescent idiopathic scoliosis (AIS).

OBJECTIVE

The objective of the study was to compare perioperative parameters and outcomes between pedicle screw and hybrid instrumentation for the treatment of AIS.

SUMMARY OF BACKGROUND DATA

Pedicle screws have been shown to allow for better correction and fewer revisions than hybrid systems. However, no study has compared perioperative parameters and their effects on patient morbidity between these 2 types of instrumentation.

METHODS

Fifty-six pediatric patients with AIS were included in the study. Twenty-seven patients were treated with hybrid instrumentation and 29 patients were treated with all pedicle screw (APS) instrumentation. Intraoperative and perioperative measures were compared.

RESULTS

The mean preoperative major Cobb angle was 58.7 degrees in the hybrid group and 54.5 degrees in the APS group (P = 0.222). Patients in the hybrid group required more time in the intensive care unit (2.0 vs. 1.1 d, P = 0.041), more time to initial mobilization (5.1 vs. 2.1 d, P < 0.001), and more days using patient-controlled analgesia (5.7 vs. 4.4 d, P = 0.020). The hybrid group averaged less estimated blood loss than the APS group (619.6 vs. 947.4 mL, P = 0.011). There was no difference in surgical time (P = 0.183) or length of stay (P = 0.072) between the groups. Thoracolumbosacral orthoses were used in 81.5% of patients in the hybrid group, but in no patients in the APS group (P < 0.001). Postoperative complications occurred in 37.0% of patients in the hybrid group and 17.2% of patients in the APS group (P = 0.095).

CONCLUSIONS

This study demonstrates several advantages of pedicle screw constructs over hybrid constructs in the surgical treatment of AIS. The benefits of pedicle screw systems extend directly to the patient and can lower the overall cost of treatment.

Treatment of severe scoliosis with posterior-only approach arthrodesis and all-pedicle screw instrumentation

PURPOSE

Posterior-only approach arthrodesis by all-pedicle screw instrumentation has a correction rate similar to correction obtained by traditional combined anterior/posterior approach surgery and avoids the complications associated with the thoracic approach.

METHODS

We treated 25 patients, with a mean age 16.5 years, with severe adolescent idiopathic scoliosis by posterior-only approach using all-screw instrumentation arthrodesis. Mean scoliosis curve in Cobb degrees was 95° Cobb. All cases were treated by the same senior surgeon, by free hand technique, without intraoperative neurophysiologic monitoring and spine navigation aids.

RESULTS

Mean scoliosis curve after surgery was 37° Cobb. Mean follow-up was 4 years. No perioperative complications, curve progression or arthrodesis malunion were reported at the follow-up.

CONCLUSIONS

Posterior spinal fusion with pedicle screw-only instrumentation obtains a good and stable correction of severe scoliosis; compared to hybrid instrumentation, it allows a greater coronal correction of the deformity and less correction loss at the follow-up.

Intraoperative skull-femoral (skeletal) traction in surgical correction of severe scoliosis (>80°) in adult neglected scoliosis

STUDY DESIGN

Retrospective review.

OBJECTIVE

To evaluate the effectiveness, safety, and reliability of intraoperative skeletal traction in the surgical correction of severe adult neglected scoliosis.

SUMMARY OF BACKGROUND DATA

Literature shows that curves more than 80° that do not reduce to 50° to 55° on bending radiographs require an anterior release. A combined anterior and posterior approach is often used for treating severe rigid scoliosis. However, anterior approach has its own complications in the form of increased morbidity, increased blood loss, operative time, and pulmonary complications. Corrective surgery gets even more challenging if the patients are adults.

METHODS

Ten patients with severe scoliosis (>80°) and low flexibility index (<0.5) treated with intraoperative skeletal traction were part of this study. The patients were operated between April 2008 and May 2010. Eight patients with neglected adolescent idiopathic scoliosis and 2 with neuromuscular scoliosis were included. The mean age was 27.4 years (19-36). Corrective surgery and fusion was performed using intraoperative skeletal traction.

RESULTS

The Cobb angle improved from a mean of 89.35° preoperatively to 40.25° postoperatively giving a mean correction of 55.29%. Apical vertebral rotation (Nash and Moe) improved from a mean of grade 3(2-4) to a mean of grade 2(1-3). Apical vertebral translation improved from a mean of 2.19 cm preoperatively to 0.98 cm postoperatively (55.41% correction). There were no intraoperative adverse events or postoperative complications. All patients had good shoulder balance and were satisfied with the correction achieved.

CONCLUSION

Intraoperative skull-femoral traction can be a safe and effective method to assist correction of severe and rigid scoliosis. It facilitates surgical exposure and pedicle screw insertion. It obviates the need of an anterior release surgery and associated morbidity, thus reducing the hospital stay and costs. It provides a much simpler way to correct the sagittal and coronal imbalance, as well as the pelvic obliquity.

Metastatic spine disease in the elderly: diagnostic and management considerations

Metastatic spine disease is becoming a more frequent problem in cancer patients as advancements in treatment for primary tumors prolong patient survival. Elderly patients over 60 years of age make up the majority of these cases, with the incidence of metastatic disease several folds higher in the elderly than in any other age group. These patients are also the most challenging group to treat, given higher rates of comorbidities and decreased tolerance to medical, surgical and radiation therapies. Advancements in therapeutic strategies, including minimally invasive surgeries and stereotactic radiosurgery, have provided increasingly attractive treatment options for elderly patients owing to their decreased procedure-associated morbidity. This article will discuss efficacy and limitations of conventional, as well as more recent, treatment modalities with an emphasis on their role in the management of elderly patients.

Posterior-only surgery with strong halo-femoral traction for the treatment of adolescent idiopathic scoliotic curves more than 100°

The aim of this study was to investigate the feasibility and clinical efficacy of treatment of adolescent idiopathic scoliosis of >100° via posterior-only surgery with strong halo-femoral traction and posterior wide release. From December 2003 to August 2006, 121 patients with adolescent idiopathic scoliosis were treated in our hospital; among them, 29 patients with curves over 100° were included in this study. From December 2003 to June 2005, group A included the first 12 patients who underwent combined anterior release followed by two-week halo-femoral traction and then posterior instrumentation. From July 2005 to August 2006, 17 patients in group B underwent posterior surgery alone with strong halo-femoral traction and posterior wide release. All of the patients were followed-up for a minimum of 31 months (mean, 36 months; range, 31-41 months). There were no severe complications. All of the patients achieved bony fusion without instrumentation breakage or pseudarthrosis. There were no statistically significant differences between the two groups in gender, age, type of adolescent idiopathic scoliosis, preoperative coronal major curve values, major curve flexibility, or final follow-up major curve correction rate. The average operative time, blood loss and hospital stay in group B were less than those in group A. In adolescent idiopathic scoliosis with Cobb >100°, posterior-only surgery with strong halo-femoral traction and posterior wide release can provide comparable curve correction with shorter operative time, less blood loss and shorter hospital stay when compared to combined anteroposterior surgery.

Comparative analysis between shape memory alloy-based correction and traditional correction technique in pedicle screws constructs for treating severe scoliosis

The three-dimensional correction of severe rigid scoliosis has been improved by segmental pedicle screw instrumentation. However, there can be significant difficulty related to the use of a rigid rod, especially in the apex region of severe scoliosis. This study is a retrospective matched cohort study to evaluate the advantages of Nitinol shape memory alloy (SMA) rod-based correction by comparing the clinical and radiographic results obtained from using a temporary SMA rod and those from a standard rod in the correction of severe scoliosis. From May 2004 to September 2006, patients with matched curve type, ages at surgery, operative methods and fusion levels in our institute and instrumented with either SMA rods (n = 14) or traditional correction techniques (n = 16) were reviewed. In SMA group, the SMA rods served as a temporary intraoperative tool for deformity correction and were replaced by standard rods. The blood loss at surgery averaged 778 +/- 285 ml in the traditional group and 585 +/- 188 ml in the SMA group (P < 0.05). Operative time averaged 284 +/- 53 min in the SMA group and 324 +/- 41 min in the traditional group (P < 0.05). In the SMA group, the preoperative major curve was 92.6 degrees +/- 13.7 degrees with a flexibility of 25.5 +/- 7.3% was corrected to 29.4 degrees +/- 5.7 degrees demonstrating a 68.4% immediate postoperative correction. In the traditional group, the preoperative major curve was 88.6 degrees +/- 14.6 degrees with a flexibility of 29.3 +/- 6.6% was corrected to 37.2 degrees +/- 7.3 degrees demonstrating a 57.8% immediate postoperative correction. There was a statistic difference between the SMA group and traditional group in correction rate of the major thoracic curve. In the SMA group, one case suffered from deep infection 2 months postoperatively. In the traditional group, 6 of 16 cases suffered pedicle screw pull out or loosening during placement of the standard rod at the apex vertebrae on the concave side. In three cases, the mono-axial pedicle screws near the apex were abandoned and in five cases replaced with poly-axial pedicle screws. This study shows that the temporary use of SMA rod may reduce the operative time, blood loss, while improve the correction of the coronal plane when compared with standard techniques.

Posterior fusion only for thoracic adolescent idiopathic scoliosis of more than 80 degrees: pedicle screws versus hybrid instrumentation

The treatment of thoracic adolescent idiopathic scoliosis (AIS) of more than 80 degrees traditionally consisted of a combined procedure, an anterior release performed through an open thoracotomy followed by a posterior fusion. Recently, some studies have reassessed the role of posterior fusion only as treatment for severe thoracic AIS; the correction rate of the thoracic curves was comparable to most series of combined anterior and posterior surgery, with shorter surgery time and without the negative effect on pulmonary function of anterior transthoracic exposure. Compared with other studies published so far on the use of posterior fusion alone for severe thoracic AIS, the present study examines a larger group of patients (52 cases) reviewed at a longer follow-up (average 6.7 years, range 4.5-8.5 years). The aim of the study was to evaluate the clinical and radiographic outcome of surgical treatment for severe thoracic (>80 degrees) AIS treated with posterior spinal fusion alone, and compare comprehensively the results of posterior fusion with a hybrid construct (proximal hooks and distal pedicle screws) versus a pedicle screw instrumentation. All patients (n = 52) with main thoracic AIS curves greater than 80 degrees (Lenke type 1, 2, 3, and 4), surgically treated between 1996 and 2000 at one institution, by posterior spinal fusion either with hybrid instrumentation (PSF-H group; n = 27 patients), or with pedicle screw-only construct (PSF-S group; n = 25 patients) were reviewed. There were no differences between the two groups in terms of age, Risser's sign, Cobb preoperative main thoracic (MT) curve magnitude (PSF-H: 92 degrees vs. PSF-S: 88 degrees), or flexibility on bending films (PSF-H: 27% vs. PSF-S: 25%). Statistical analysis was performed using the t test (paired and unpaired), Wilcoxon test for non-parametric paired analysis, and the Mann-Whitney test for non-parametric unpaired analysis. At the last follow-up, the PSF-S group, when compared to the PSF-H group had a final MT correction rate of 52.4 versus 44.52% (P = 0.001), with a loss of -1.9 degrees versus -11.3 degrees (P = 0.0005), a TL/L correction of 50 versus 43% (ns), a greater correction of the lowest instrumented vertebra translation (-1.00 vs. -0.54 cm; P = 0.04), and tilt (-19 degrees vs. -10 degrees; P = 0.005) on the coronal plane. There were no statistically significant differences in sagittal and global coronal alignment between the two groups (C7-S1 offset: PSF-H = 0.5 cm vs. PSF-S = 0 cm). In the hybrid series (27 patients) surgery-related complications necessitated three revision surgeries, whereas in the screw group (25 patients) one revision surgery was performed. No neurological complications or deep wound infection occurred in this series. In conclusion, posterior spinal fusion for severe thoracic AIS with pedicle screws only, when compared to hybrid construct, allowed a greater coronal correction of both main thoracic and secondary lumbar curves, less loss of the postoperative correction achieved, and fewer revision surgeries. Posterior-only fusion with pedicle screws enabled a good and stable correction of severe scoliosis. However, severe curves may be amenable to hybrid instrumentation that produced analogous results to the screws-only constructs concerning patient satisfaction; at the latest follow-up, SRS-30 and SF-36 scores did not show any statistical differences between the two groups.

Operative treatment of adolescent idiopathic scoliosis with posterior pedicle screw-only constructs: minimum three-year follow-up of one hundred fourteen cases

STUDY DESIGN

Preoperative review of a prospective study, single institution, consecutive series. OBJECTIVE.: To analyze the intermediate-term follow-up of consecutive adolescent idiopathic scoliosis (AIS) patients treated with pedicle screw constructs.

SUMMARY OF BACKGROUND DATA

There have been no reports of the intermediate-term findings in North America following posterior spinal fusion with the use of pedicle screw-only constructs.

METHODS

One hundred and fourteen consecutive patients having a minimum 3-year follow-up (mean 4.8 +/- 1.1; range, 3.0-7.3 years) with AIS were evaluated. The average age at surgery was 14.9 +/- 2.2 years. Radiographic measurements included preoperative (Preop), postoperative (PO), 2-year (2 years), and final follow-up (FFU). A chart review evaluated PFTs, Scoliosis Research Society scores, presence of thoracoplasty, Risser sign, Lenke classification, and complications.

RESULTS

The most frequent curve pattern was Lenke type 1 (45.6%), followed by type 3 (21.9%). The average main thoracic curve measured 59.2 degrees +/- 12.2 SD Preop, and corrected to 16.8 degrees +/- 9.9 PO (P < 0.0001). Sagittal thoracic alignment (T5-T12) decreased from 25.8 degrees to 15.5 degrees at FFU (P = 0.05). Nash-Moe grading for apical vertebral rotation (AVR) in the proximal thoracic curve decreased from 2.0 Preop to 1.1 at FFU (P < 0.0001), and AVR in the thoracolumbar/lumbar spine decreased from 1.6 Preop to 1.1 at FFU (P < 0.0001). Importantly, the horizontalization of the subjacent disc measured -8.3 degrees Preop which decreased to -0.9 degrees PO (P < 0.001). PFT follow-up averaged 2.4 years with a 7.1% improvement in FVC (P = 0.004) and 8.8% in FEV1 (P < 0.0001). SRS scores averaged 83.0% at latest follow-up. Age, gender, Risser sign, or complications did not have a significant effect on outcomes. There were 2 cases of adding-on, 3 late onset infections, 1 with a single pseudarthrosis, but no neurologic complications.

CONCLUSION

This is the largest (N = 114), consecutive series of North American patients with AIS treated with pedicle screws having a minimum of 3-year follow-up. The average curve correction was 68% for the main thoracic, 50% for the proximal thoracic, and 66% for the thoracolumbar/lumbar curve at final follow-up.

Financial analysis of circumferential fusion versus posterior-only with thoracic pedicle screw constructs for main thoracic idiopathic curves between 70 degrees and 100 degrees

PURPOSE

Reports on thoracic pedicle screw (TPS) constructs have demonstrated their safety and efficacy; however, concerns exist regarding their increased cost. This is a review of adolescents with main thoracic scoliosis surgically treated with anterior release and posterior fusion or posterior fusion only. The objectives were to compare the radiographic outcomes and financial data of two surgical treatments: anterior/posterior spinal fusion (APSF) versus posterior spinal fusion (PSF-TPS) alone with TPSs, in patients with large 70-100 degrees main thoracic adolescent idiopathic scoliosis (AIS) curves.

METHODS

We identified 43 patients with main thoracic Lenke type 1-4 AIS curves between 70 and 100 degrees who had been treated with either APSF or PSF-TPS.

RESULTS

Both groups had equivalent radiographic corrections postoperatively. The PSF-TPS group patients had higher implant charges, but the APSF group had higher surgeon procedural charges, operating room charges, anesthesia charges, and inpatient room charges. Total charges were $75,295 for the APSF group and $71,236 for the PSF-TPS group (P > 0.05). Analyses of two subgroups of the APSF group, anterior release via thoracotomy versus VATS and same-day versus staged surgeries, failed to change any of the above findings.

CONCLUSION

Based on this financial analysis, there was no statistically significant differences between the APSF and PSF-TPS groups, with equivalent radiographic corrections.

Clinical Analysis of Video-assisted Thoracoscopic Spinal Surgery in the Thoracic or Thoracolumbar Spinal Pathologies

OBJECTIVE

Thoracoscopic spinal surgery provides minimally invasive approaches for effective vertebral decompression and reconstruction of the thoracic and thoracolumbar spine, while surgery related morbidity can be significantly lowered. This study analyzes clinical results of thoracoscopic spinal surgery performed at our institute.

METHODS

Twenty consecutive patients underwent video-assisted thoracosopic surgery (VATS) to treat various thoracic and thoracolumbar pathologies from April 2000 to July 2006. The lesions consisted of spinal trauma (13 cases), thoracic disc herniation (4 cases), tuberculous spondylitis (1 case), post-operative thoracolumbar kyphosis (1 case) and thoracic tumor (1 case). The level of operation included upper thoracic lesions (3 cases), midthoracic lesions (6 cases) and thoracolumbar lesions (11 cases). We classified the procedure into three groups: stand-alone thoracoscopic discectomy (3 cases), thoracoscopic fusion (11 cases) and video assisted mini-thoracotomy (6 cases).

RESULTS

Analysis on the Frankel performance scale in spinal trauma patients (13 cases), showed a total of 7 patients who had neurological impairment preoperatively : Grade D (2 cases), Grade C (2 cases), Grade B (1 case), and Grade A (2 cases). Four patients were neurologically improved postoperatively, two patients were improved from C to E, one improved from grade D to E and one improved from grade B to grade D. The preoperative Cobb's and kyphotic angle were measured in spinal trauma patients and were 18.9+/-4.4 degrees and 18.8+/-4.6 degrees , respectively. Postoperatively, the angles showed statistically significant improvement, 15.1+/-3.7 degrees and 11.3+/-2.4 degrees , respectively (P<0.001).

CONCLUSION

Although VATS requires a steep learning curve, it is an effective and minimally invasive procedure which provides biomechanical stability in terms of anterior column decompression and reconstruction for anterior load bearing, and preservation of intercostal muscles and diaphragm.

Treatment of stiff thoracic scoliosis by thoracoscopic anterior release combined with posterior instrumentation and fusion

BACKGROUND

Thoracoscopic anterior release has been shown that it can effectively improve spinal flexibility in animal and human cadaveric studies, and has been advocated for use in patients with scoliosis. This prospective case series aims to investigate the improvement of the spinal flexibility and the effectiveness in deformity correction by anterior thoracoscopic release and posterior spinal fusion.

METHODS

Eleven patients with stiff idiopathic thoracic scoliosis underwent anterior thoracoscopic release followed by posterior instrumentation. The average number of discs excised was five. Spinal flexibility was assessed by the fulcrum bending technique. Cobb angle before and after the anterior release was compared.

RESULTS

The patients were followed for an average of 5.6 years (range 2.2 to 8.1 years). Fulcrum bending flexibility was increased from 39% before the thoracoscopic anterior spinal release to 54% after the release. The average Cobb angle before anterior release was 74 degrees on the standing radiograph and 45 degrees with the fulcrum-bending radiograph. This reduced to 34 degrees on the fulcrum-bending radiograph after the release, and highly corresponded to the 31 degrees measured at the post-operative standing radiograph.

CONCLUSION

It was demonstrated in patients with stiff idiopathic thoracic scoliosis that thoracoscopic anterior spinal release can effectively improve the spinal flexibility and increase the correction of the spinal deformity.

Is anterior release necessary in severe scoliosis treated by posterior segmental pedicle screw fixation?

With the advent of segmental pedicle screw fixation that enables more powerful corrective forces, it is postulated that an additional anterior procedure may be unnecessary even in severe deformities. The purpose of this paper is to evaluate the results of a posterior procedure alone using segmental pedicle screw fixation in severe scoliotic curves over 70 degrees . Thirty-five scoliosis patients treated by pedicle screw fixation and rod derotation were retrospectively analyzed after a minimum follow-up of 2 years (range 2-10.4). The mean age of patients was 15.3 years (range 9.8-34.2). Diagnoses were idiopathic scoliosis in 29, neuromuscular scoliosis in 3 and scoliosis associated with Marfan syndrome in 3. Scoliosis consisted of single thoracic curve in 18, double thoracic in 5 and double major in 12. Twenty-five patients showed a major thoracic curve greater than 70 degrees (range 70-100), and different ten patients showed a major lumbar curve greater than 70 degrees (range 70-105), pre-operatively. The deformity angle, lowest instrumented vertebral tilt (LIVT) and spinal balance were measured. Pre-operatively there were nine patients with coronal decompensation. The pre-operative thoracic curve of 80 +/- 9 degrees with the flexibility of 45 +/- 11% (45 +/- 11 degrees in side-bending film) was corrected to 27 +/- 10 degrees at the most recent follow-up, showing a correction of 66% (53 degrees) and loss of correction of 3.0% (3.7 degrees). The pre-operative lumbar curve of 79 +/- 12 degrees with the flexibility of 62 +/- 14% (30 +/- 11 degrees in side-bending film) was corrected to 33 +/- 14 degrees at the most recent follow-up [59% (46 degrees) curve correction, 3.5% (3.0 degrees) loss of curve correction]. The pre-operative LIVT of 30 +/- 8 degrees was corrected to 11 +/- 6 degrees, showing a correction of 62% (19 degrees). Residual coronal decompensation was observed in three patients postoperatively. Pre-operative thoracic kyphosis of 27 degrees (range 0-82) improved postoperatively to 31 degrees (range 14-53). In conclusion, posterior segmental pedicle screw fixation without anterior release in severe scoliosis had satisfactory deformity correction without significant loss of curve correction. In this series a posterior procedure alone obviated the need for the anterior release and avoided complications related anterior surgery.

The anatomical relationship between the aorta and the thoracic vertebral bodies and its importance in the placement of the screw in thoracoscopic correction of scoliosis

Thoracoscopically-assisted anterior spinal instrumentation is being used widely to treat adolescent idiopathic scoliosis (AIS). Recent studies have showed that screws placed thoracoscopically could counter the aorta or entrance into the spinal canal. There are a few studies defining the anatomic landmarks to identify the relationship between the aorta and the thoracic vertebral body using quantitative measurement for the sake of safe placement of thoracoscopic vertebral screw in anterior correction for AIS. The CT scanning from T4 to T12 in 64 control subjects and 30 AIS patients from mainland China were analyzed manually. Parameters to be measured included the angle for safety screw placement (alpha), the angle of the aorta relative to the vertebral body (beta), the distance from the line between the left and the right rib heads to the anterior wall of the vertebral canal (a), the distance from the left rib head to posterior wall of the aorta (b), the vertebral body transverse diameter (c) and vertebral rotation (gamma). No significant differences were found between the groups with respect to age or sex. Compared with the control group, alpha angle from T7 to T10, beta angle from T5 to T10 and b value at T9, T10 were significantly lower in the scoliotic group. The a value was significantly lower in the scoliotic group. The c value showed no significant difference between the two groups. In conclusion, to place the thoracoscopic vertebral screw safely, at the cephalad thoracic spine (T4-T6), the maximum ventral excursion angle should decrease gradually from 20 degrees to 5 degrees , the entry-point of the screw should be close to the rib head. For apical vertebrae (T7-T9), the maximum ventral excursion angle increased gradually from 5 degrees to 12 degrees. At the caudal thoracic spine (T10-T12), the maximum ventral excursion angle increased, the entry-point should shift 3 approximately 5 mm ventrally.

Histomorphometric assessment of thoracoscopically assisted anterior release in a porcine model: safety and completeness of disc discectomy with surgeon learning curve

STUDY DESIGN

A retrospective study using histomorphometric analysis to quantify the percentage of discectomy following thoracoscopic anterior release and fusion in a porcine model.

OBJECTIVE

To investigate the safety and completeness of disc and endplate removal with respect to the learning curve of the surgeon in a porcine thoracoscopic anterior fusion model.

SUMMARY OF BACKGROUND DATA

The thoracoscopic approach has been used to perform an anterior release and fusion before an open posterior instrumentation, however, there is concern that the technique may not provide sufficient visualization or exposure to perform safely and completely.

METHODS

A total of 32 pigs (160 discs) were assigned to 2 groups (early experience, n = 16; late experience, n = 16), and underwent 5 level thoracoscopic anterior release followed by anterior instrumentation and fusion from T5 to T10. At 4 months after surgery, the spines were harvested, and each discectomy disc was histomorphometrically analyzed to determine the percentage of disc excision and amount of endplate removal.

RESULTS

There were no significant differences in the percent disc excision between the early (67% +/- 11%) and late groups (69% +/- 10%). Greater than 50% of the disc was excised in 151 of 160 discectomies (94%). Both superior and inferior endplates were resected in 92 of 160 disc levels (57%). The amount of endplate removal had improved over time in both early and late groups (P < 0.0001). The histologic examination revealed no evidence for posterior longitudinal ligament disruption or spinal canal encroachment in any disc.

CONCLUSIONS

Video-assisted thoracoscopic discectomy is safe and allows for a significant amount of disc material excision. This study did not demonstrate a learning curve with respect to the amount of disc material excised, but a learning curve was seen for endplate excision.

Is anterior release effective to increase flexibility in idiopathic thoracic scoliosis? Assessment by traction films

With the advent of thoracoscopy, anterior release procedures in adolescent idiopathic scoliosis (AIS) have come into more frequent use, however, the indication criteria for an anterior release in thoracic AIS are still controversial in the literature. To date, few studies have assessed the influence on spinal flexibility and no study has so far been able to show a beneficial effect on the correction rate as compared to a single posterior procedure. The objective of this study was to evaluate the influence of thoracic disc excision on coronal spinal flexibility. Six patients (5 females, 1 male) with AIS and a mean age of 15.6 years (range 13-20 years) underwent an open anterior thoracic release prior to posterior instrumentation. Cotrel dynamic traction along with radiographs of the whole spine including traction films were conducted pre- and postoperatively and were evaluated retrospectively. The mean preoperative thoracic curve was 89.7 degrees +/- 15.4 degrees (range 65 degrees-110 degrees). The flexibility rate in Cotrel traction was 22.8 +/- 8.1%. After performance of the anterior release the thoracic curve showed a mean increase of coronal correction by 5.5 degrees +/- 5.0 degrees as assessed by traction radiographs. The flexibility index changed by 6.2 +/- 5.6%. After posterior instrumentation the thoracic curve was corrected to a mean of 36.5 degrees +/- 10.1 degrees (correction rate 59.6%). Disc excision in idiopathic thoracic scoliosis only slightly increased spinal flexibility as assessed by traction films. In our view a posterior release with osteotomy of the concave ribs (concave thoracoplasty, CTP) is more effective in increasing spinal flexibility. According to our clinical experience, an anterior release prior to posterior instrumentation in AIS should only be considered in hyperkyphosis, coronal imbalance or massive curves.

In-vivo demonstration of the effectiveness of thoracoscopic anterior release using the fulcrum-bending radiograph: a report of five cases

Thoracoscopic anterior release of stiff scoliotic curves is favored because of its minimally invasive nature. Animal and human cadaveric studies have shown that it can effectively improve spinal flexibility in non-scoliotic spines; however it has not been demonstrated to be effective in actual patients with scoliosis. The fulcrum-bending radiograph has been shown to accurately reflect the post-operative correction. To demonstrate that the flexibility was increased after the anterior release; five patients with idiopathic thoracic scoliosis who underwent staged anterior thoracoscopic release and posterior spinal fusion were assessed using the fulcrum-bending radiograph. The average number of discs excised was four. Spinal flexibility as revealed by the fulcrum-bending technique, was compared before and after the anterior release. The patients were followed for an average of 4 years (range 2.2-4.9 years). Fulcrum-bending flexibility was increased from 39% before the thoracoscopic anterior spinal release to 54% after the release (P<0.05). The average Cobb angle before the anterior release was 71 degrees on the standing radiograph and 43 degrees with the fulcrum-bending radiograph. This reduced to 33 degrees on the fulcrum-bending radiograph after the release, and highly corresponded to the 30 degrees measured at the post-operative standing radiograph and at the latest follow-up. Previous animal and cadaveric studies demonstrating the effectiveness of thoracoscopic anterior release did not have scoliosis. We are able to demonstrate in patients with adolescent idiopathic scoliosis, that thoracoscopic anterior spinal release effectively improves the spinal flexibility.

A Large Adolescent Idiopathic Scoliosis Curve in a Skeletally Immature Patient: Is Early Surgery the Correct Approach?

The goal of this study was to determine whether the available studies provide enough evidence that, in a borderline case of adolescent idiopathic scoliosis with a large (35 to 50 degrees) curve in a skeletally immature patient (Risser 0 to 2) with significant growth potential left, a conservative line of management in the form of bracing can be considered, rather than to rush into a potentially unnecessary major spinal surgery. We reviewed the literature spanning the last 20 years for the results of bracing in this specific group of patients. From the 9 studies selected, a group-specific data extraction was carried out. Three hundred and five patients with a 36 to 50 degrees scoliosis curve and Risser stages 0 to 2 were treated by bracing and the treatment was termed successful in 160 patients. Thus, more than half (52.5%) of the patients were successfully managed with a brace and were spared surgery. The current trend for management of these curves is early surgical intervention, the rationale being the ineffectiveness of bracing in preventing the progression of such a large curve and the difficulty in obtaining satisfactory correction by postponing surgery to a later date. On the basis of our results, we propose a conservative line of management for these curves, in contrast with current views, rather than to rush into a major spine surgery, expecting a favorable outcome with a well-supervised bracing program. If the curve progresses, surgery can always be considered later, keeping in mind the excellent correction obtained with the pedicle screw systems even for large curves of 70 to 100 degrees.

Mini-open thoracoscopically assisted thoracotomy versus video-assisted thoracoscopic surgery for anterior release in thoracic scoliosis and kyphosis: a comparison of operative and radiographic results

BACKGROUND CONTEXT

Combining anterior release and interbody fusion with posterior instrumented fusion is an accepted treatment for severe rigid spinal deformity. Video-assisted thoracoscopic surgery (VATS) and mini-open thoracoscopically assisted thoracotomy (MOTA) are two minimally invasive approaches to the thoracic spine. Both reduce surgical trauma, improve cosmesis and provide effective exposure for release and fusion. Published data and the authors' surgical experience have demonstrated that both techniques are equivalent in degree of release to traditional open thoracotomy, but no comparison between these two minimally invasive alternatives has been published to our knowledge.

PURPOSE

This study compared MOTA and VATS under the hypothesis that both result in similar corrections and comparable operative parameters when used in conjunction with posterior instrumented fusion.

STUDY DESIGN/SETTING

Retrospective chart review of consecutive case series by two surgeons.

PATIENT SAMPLE

Twenty-one (13 female, 8 male) patients underwent MOTA and 24 patients (17 female, 7 male) underwent VATS for anterior release, discectomy and fusion prior to posterior instrumented fusion.

OUTCOME MEASURES

Outcomes were measured at a minimum of 1-year follow-up and included radiographic Cobb measurements and operative parameters.

METHODS

The indications for surgery included rigid and severe scoliosis or thoracic kyphosis. Data collection included preoperative demographics, number of levels released, primary curve correction, operative time and blood loss. Data were normalized per number of levels released anteriorly. Statistical analysis of results was done using a two-sample t test assuming equal variances with two-tail p values less than .05.

RESULTS

More anterior levels were operated on average in the VATS group (6.33 vs. 4.38 levels). Curve correction per anterior level released was similar in both groups (8.7 and 8.8 degrees/level for MOTA and VATS, respectively). There was a significant difference in operative time with MOTA averaging 131.7 minutes and VATS averaging 162.8 minutes. However, a comparison of the operative time per anterior level operated, approached statistical significance in favor of VATS (33.0 vs. 28.4 minutes, p=.08). There was no significant difference in estimated blood loss during the anterior portion of the surgeries. There was a trend toward decreased blood loss per operated level favoring VATS (68.4 vs. 38.9 cc, p=.09).

CONCLUSIONS

Both approaches resulted in corrections that compare favorably with open thoracotomy. We suggest that a factor in choosing between these two minimally invasive techniques is the number of thoracic levels requiring release. For four levels or less, MOTA provides an excellent alternative to standard thoracotomy. For five or more levels, VATS provides for excellent exposure of additional levels with the advantages of less operative time and blood loss per operated level.

[Complications of surgical treatment of spinal deformities: a prospective multicentric study of 3311 patients]

PURPOSE OF THE STUDY

The incidence of complications secondary to surgical treatment of spinal deformations remains imprecise. The purpose of this prospective multicentric observational study was to assess the incidence of intra- and postoperative complications secondary to this type of surgery to detail the observed complications and to identify favoring factors.

MATERIAL AND METHODS

For this study, we included 3311 patients who underwent surgery during a 12-month period for spinal deformation, defined as idiopathic or secondary scoliosis or kyphosis, irrespective of the localization, severity, or type of surgery performed. Four main categories of complications were studied: general, infectious, neurological, and mechanical. Pre- and intraoperative variables recorded were: epidemiological and morphological data, history of surgery for the same spinal deformation, comorbid conditions, type of deformation treated (nature, anatomic localization, severity, reducibility), type of surgery performed (approach, duration of the operation), operative blood loss, extent and localization of the fusion, associated neurological release, vertebral osteotomy or not, type of graft used. Two types of analysis were performed. The first was a descriptive analysis to detail the overall incidence of complications and the incidence of each of the four main categories. The second was a multivariate analysis designed to determine factors significantly associated with complication occurrence.

RESULTS

Mean age of the cohort was 27 +/- 18 years; 6.8% of the patients had had a prior operation for the spinal deformation. The deformation was scoliosis in 90% (mean angle 56 +/- 20 degrees) and kyphosis in 10% (mean angle 47 +/- 23 degrees). An isolated posterior approach was used for 72.5% of patients, an isolated anterior approach for 6.4%, and a combined anteroposterior approach for 21.1%. Seven hundred four patients (21.3%) had one or more complications (850 complications) during or shortly after their operation. The incidences of general, infectious, mechanical and neurological complications were: 5.7%, 4.7%, 11.5%, and 1.8% respectively. Globally, considering all types of complications, the following factors were found to be significantly associated with complication occurrence: patient age, ASA score, extent of the fusion, presence of vertebral osteotomy, inclusion of the sacrum in the arthrodesis, and initial angle of the treated deformation. For patients with scoliosis, the following factors were significantly associated with a secondary central neurological disorder: initial angle of the deformation, use of vertebral osteotomy, type of curvature with greater risk for thoracic curvatures and double thoracic and lumbar curvatures.

CONCLUSION

This work enabled us to determine the overall rate of complications after surgical treatment of spinal deformations. Certain risk factors related with complication occurrence were identified, but the heterogeneous nature of the population and the methodology used to identify these factors only allowed detection of trends. A future study by etiological group or focusing on specific complications should allow a more precise analysis of these risk factors. This overall rate of complications should be used to better inform patients and their family about the risks of this type of surgery.

Thoracic adolescent idiopathic scoliosis curves between 70 degrees and 100 degrees: is anterior release necessary?

STUDY DESIGN

A retrospective review of adolescents with main thoracic scoliotic curves surgically treated with either anterior release and posterior fusion or posterior fusion only.

OBJECTIVES

To compare the radiographic and clinical outcomes of two surgical treatments: anterior-posterior spinal fusion (APSF) versus posterior spinal fusion (PSF) alone in patients with large 70 degrees to 100 degrees thoracic adolescent idiopathic scoliosis (AIS) curves.

SUMMARY OF BACKGROUND DATA

Surgical treatment of thoracic AIS curves between 70 degrees and 100 degrees often consists of anterior and posterior fusion to improve the coronal correction and fusion rate, with the anterior release and fusion performed through either an open thoracotomy or by video-assisted thoracoscopy.

METHODS

All patients (n = 84) with main thoracic major AIS curves between 70 degrees and 100 degrees who underwent spinal fusion (APSF or PSF) at one center between 1987 and 2001 were included for analysis. The minimum follow-up was 2 years after surgery (mean, 4.5 years; range, 2.0-10.2 years). The mean age of patients was 13.8 years (range, 10.7-18.2 years), with 66 females and 18 males. Multiple radiographic measures were assessed. The primary and secondary statistical analyses performed were nonparametric analyses, using the Wilcoxon-Mann-Whitney tests for the primary analysis of APSF and PSF groups. The PSF subgroup analysis was performed with the Kruskal-Wallis test.

RESULTS

There were 22 patients in the APSF (open ASF in 18, and video-assisted thoracoscopy in 4) group and 62 patients in the PSF group. There were no statistically significant differences between the groups for gender, age, number of levels fused, Cobb measurement of preoperative coronal or sagittal thoracic curve magnitude, or coronal curve flexibility. The APSF group, when compared with the PSF group, had greater intraoperative correction of the coronal curve (48.3 degrees vs. 38.7 degrees, P = 0.0087) as well as final overall correction (47.2 degrees vs. 34.2 degrees, P = 0.0008). There were no significant differences seen in the sagittal alignment from T5-T12 (P = 0.3150) or the SRS outcomes data between the APSF and PSF only groups. Subanalysis of the PSF only group identified three distinct groups based on implants: hook-only constructs (n = 36), hybrid constructs of proximal hooks and distal pedicle screws (n = 15), and pedicle screw-only constructs (n = 11). Pedicle screw-only constructs corrected the coronal Cobb measurements more than the other two groups (47.5 degrees vs. hooks 37.7 degrees vs. hybrid 34.4 degrees , P = 0.0110), and to a similar extent as to the APSF group with no statistically significant difference in coronal correction (PSF, 47.5 degrees; APSF 48.3 degrees; P = 0.9014), nor any other parameter except for sagittal T5-T12 changes. There were no reoperations for implant failure/pseudarthroses in any of the patients.

CONCLUSION

APSF of large thoracic curves allows greater coronal correction of thoracic curves between 70 degrees and 100 degrees, when compared with PSF alone using thoracic hook constructs, but not with the use of thoracic pedicle screw constructs. Scoliosis surgeons not using pedicle screw constructs need to decide if the modest improvement in coronal correction with a combined approach justifies its routine use in this patient population.

The treatment of large (>70 degrees) thoracic idiopathic scoliosis curves with posterior instrumentation and arthrodesis: when is anterior release indicated?

STUDY DESIGN

Retrospective clinical study from 2 centers.

OBJECTIVE

To analyze the efficacy of posterior instrumentation and arthrodesis for thoracic idiopathic scoliosis curves more than 70 degrees.

SUMMARY OF BACKGROUND INFORMATION

The increasing use of thoracoscopic techniques in deformity surgery has led several investigators to advocate anterior release followed by posterior instrumentation when treating "stiff" thoracic curves 60 degrees-70 degrees. To our knowledge, no study has been published to define indications for anterior surgery in thoracic idiopathic scoliosis.

METHODS

This is a retrospective review of patients 20 years and younger, with idiopathic scoliosis and thoracic curves more than 70 degrees treated with isolated posterior instrumentation and arthrodesis at 2 institutions from 1989 to 1999. A total of 50 patients were identified, and 46 were available for minimum 2-year radiographic follow-up. Of the 50 patients, 44 had bend films taken before surgery. All patients were treated with third-generation segmental spinal instrumentation using a varied combination of hooks, wires, and screws.

RESULTS

Average patient age at surgery was 14.4 years (range 10-20), and average radiographic follow-up was 4.4 years (range 2-11.5). Average preoperative thoracic curve was 75 degrees (range 70 degrees-88 degrees), and average bend was 47 degrees (range 28 degrees-60 degrees), a flexibility of 37%. Average postoperative curve was 25 degrees (range 10 degrees-46 degrees), and it was 27 degrees (range 11 degrees-46 degrees) at latest follow-up, a correction of 64%. The average length of surgery was 6.15 hours, mean hospital stay was 8 days, and average blood loss was 1100 cc. The Scoliosis Research Society 22 or 24 was available at a minimum of 2 years in 46 of 50 patients. Mean domain scores were: pain 4.4, self-image 4.3, function 4.3, mental health 4.3, satisfaction 4.7, and total 4.4. Complications included 1 pseudarthrosis, 1 implant removal for prominence, and 1 implant removal for late operative site pain.

CONCLUSION

Using posterior surgery only, we have been able to at least equal the results reported in the literature by investigators using combined approaches. Isolated posterior instrumentation and arthrodesis achieve satisfactory cosmetic, radiographic, and patient-based outcomes in adolescents with idiopathic scoliosis with thoracic curves 70 degrees-90 degrees, without the added expense and morbidity of anterior release.

Prospective evaluation of 50 consecutive scoliosis patients surgically treated with thoracoscopic anterior instrumentation

STUDY DESIGN

Prospective, consecutive, single-surgeon case series of patients treated for scoliosis with thoracoscopic anterior spinal instrumentation.

BACKGROUND

A thoracoscopic approach for insertion of anterior instrumentation has been developed in the past 10 years, which obviates many of the disadvantages of the open anterior thoracic approach. The morbidity associated with a thoracoscopy is limited because of the minimal skin and chest wall dissection required with this method.

PURPOSE

The purpose of this evaluation is to report a single surgeon's experience with an initial series of 50 patients. The goal is to report the outcomes with regards to the radiographic findings, pulmonary function, and the SRS Outcomes Instrument, as well as a review of the perioperative data and complications.

METHODS

The primary author's initial 50 thoracoscopic anterior spinal instrumentation patients were consecutively collected. Data collection included demographics, such as age, gender, and diagnosis. Data regarding the surgical procedure included the operative time, intraoperative estimated blood loss, as well as the number of levels instrumented anteriorly. In the perioperative hospital period, data were collected with regard to the length of the hospital stay, the number of days in the ICU, the number of days of ventilator support, and the number of days after surgery when conversion from IV to PO pain medication occurred. Radiographic data were obtained systematically on each patient and measured by authors other than the surgeon. The SRS 22 and/or 24 Outcomes Questionnaire and pulmonary function tests were administered to patients at similar intervals.

RESULTS

The series consisted of 44 females and 6 males with a mean age of 14 years (range, 9-48 years). Forty-five of the 50 patients were available for clinical and radiographic evaluation at greater than or equal to 2 years after surgery. The average length of follow-up for these 45 patients was 33 months (range, 2-5 years). The mean operative time for the procedure was 350 +/- 50 minutes and ranged from 265 to 528 minutes. The estimated intraoperative blood loss averaged 431 +/- 273 mL (range, 75-1,400 mL). Normalizing the operative time and estimated blood loss based on the number of levels treated resulted in an average operative time per level of 48 +/- 6 minutes per level and an estimated intraoperative blood loss per level of 60 +/- 37 mL per level. The preoperative thoracic Cobb averaged 53 degrees +/- 9 degrees (range, 40 degrees-80 degrees). At most recent follow-up (> or = 2 years), the thoracic Cobb averaged 24 degrees +/- 7 degrees. Implant failure occurred in 3 cases.

CONCLUSION

Thoracoscopic anterior instrumentation for adolescent idiopathic scoliosis is a viable surgical option. The outcomes of this consecutive series of patients is comparable to prior open and endoscopic series presented in the literature. The technical challenges of this operation are evident in the learning curve effect, which has been demonstrated.

Video-assisted thoracoscopic surgery: the Cincinnati experience

Video-assisted thoracoscopic surgery is an alternative to open thoracotomy. We analyzed our experience during a consecutive series of 100 patients who had this procedure and who were available for study at 3-year followup. Video-assisted thoracoscopic surgery was done on patients with the following diagnoses: idiopathic scoliosis (n = 49), neuromuscular spinal deformity (n = 15), Scheuermann kyphosis (n = 15), congenital and infantile scoliosis (n = 5), neurofibromatosis (n = 5), Marfan (n = 1), postradiation scoliosis (n = 1), and repair of pseudoarthrosis (n = 1). Four patients had excision of the first rib to treat thoracic outlet syndrome. One patient had excision of an intrathoracic neurofibroma and one a benign rib tumor. One had anterior arthrodesis after fracture-dislocation of the thoracic spine and another had anterior fusion for vertebral osteomyelitis. The average operative time for the thoracoscopic anterior release with discectomy and arthrodesis was 253 minutes. The average number of discs excised was 8. Final postoperative scoliosis and kyphosis corrections were 68% and 90%, respectively. Complications related to thoracoscopy occurred in eight patients. Video-assisted thoracoscopic surgery provides a safe and effective alternative to open thoracotomy in the treatment of thoracic pediatric spinal deformities.

The success of thoracoscopic anterior fusion in a consecutive series of 112 pediatric spinal deformity cases

STUDY DESIGN

A retrospective review of a single surgeon consecutive series of video-assisted thoracoscopic anterior release and fusion.

OBJECTIVES

To examine radiographic fusion rates and standard radiographic parameters of spinal deformity correction, as well as to identify possible complications of thoracoscopic anterior release and fusion in patients with a minimum of 2-year follow-up treated for spinal deformity.

SUMMARY OF BACKGROUND DATA

Anterior release and fusion of the thoracic spine is indicated in the treatment of rigid scoliosis and kyphosis, the treatment or prevention of crankshaft growth, and in patients at increased risk for pseudarthrosis. Although early postoperative outcomes of video-assisted thoracoscopic anterior release/fusion exist in the literature, few data are available with follow-up greater than 2 years.

METHODS

A retrospective chart and radiograph review of 112 consecutive cases of thoracoscopic anterior release/fusion with open posterior instrumentation/fusion was performed. The diagnosis, indications, perioperative data, as well as early and delayed complications, were evaluated. Deformity correction and intervertebral fusion rates were assessed at latest follow-up (> or =2 years).

RESULTS

The diagnoses included 50 patients with neuromuscular deformity, 42 with idiopathic deformity, 10 congenital, and 10 miscellaneous etiologies. The average operative time was 160 +/- 41 minutes to excise and bone graft an average of 7 +/- 2 discs, with an average blood loss of 285 +/- 303 cc. The average hospital stay was 9 +/- 5 days. Fourteen percent of the patients had perioperative respiratory complications that varied from atelectasis to chylothorax. There were no long-term complications associated with the anterior surgery. Scoliosis improved from 80 +/- 12 degrees to 36 +/- 17 degrees, and kyphosis from 88 +/- 15 degrees to 60 +/- 20 degrees at latest evaluation (P < or = 0.001). Evidence of a "solid" anterior arthrodesis (with >50% filling of the disc space) was present radiographically in 75% of the disc spaces with moderate interobserver reliability of the grading system (kappa = 0.49).

CONCLUSION

Thoracoscopic anterior release and fusion of the thoracic spine is a safe and effective procedure when combined with posterior instrumentation and fusion. The primary goal of increasing the flexibility of a rigid spine and achieving a solid arthrodesis occurred in the vast majority of cases.

Is there a need for anterior release for 70-90 degrees masculine thoracic curves in adolescent scoliosis?

Large and stiff thoracic scoliotic curves in the adolescent represent a classic indication of anterior release followed by posterior instrumentation. However, third-generation segmental spinal instrumentations have shown increased correction of thoracic curves. Indication for an anterior release may therefore not be required even in large and stiff thoracic curves. The objective of the study was, therefore, to analyze retrospectively the results of third-generation segmental posterior instrumentation in large and stiff thoracic curves and to compare our results with the current literature of anterior release followed by posterior instrumentation. An independent observer, who had not participated in any of the case, reviewed our electronic database of adolescent scoliosis surgery (Scolisoft) with the following query: thoracic curves, Cobb angle between 70 degrees and 90 degrees and posterior surgery only. He was able to identify 19 patients whose thoracic curves were measured between 70 degrees and 90 degrees . Out of these, four had convex-side bending Cobb angle values of less than 45 degrees and were not included in the study, as they were judged too flexible. Fifteen patients (aged 11-18 years, mean 13.6 years) with thoracic scoliosis were left for the study (average Cobb angles 78.5 degrees with a flexibility index of 32.5% (range, 19-42%). The mean follow-up period was 32 months (range 18-64 months). Classic parameters of deformity correction were analysed. The average operative time was 314 min and the mean total blood loss was 1,875 ml. Average level of instrumented vertebrae was 12 (Range, 10-14). Postoperatively, the thoracic Cobb angle was measured at 34.8 degrees (range, 25-45 degrees ), which represents a correction rate of 54% (range, 40.0-67.1%) and remained unchanged at the last follow-up (35 degrees ). Patients with thoracic hypokyphosis improved from an average 11 degrees to 18 degrees . There were three complications (one excessive bleeding, one early infection and one late infection). One case showed an add-on phenomenon at the last follow-up. Coronal balance was improved from 1.8 cm (Range 0-4 cm) down to 0.75 cm (range 0-2.5 cm). Shoulder balance was improved from 1.3 cm (range 0-4 cm) down to 0.75 (0-2.5 cm). All patients reported satisfactory results except the patient with an adding-on phenomena. In the literature, most of the results of anterior thoracoscopic release and posterior surgery give a percentage of Cobb angle correction similar or inferior to our series for an average initial Cobb angle of less magnitude. Therefore, with adequate posterior release, and the use of third-generation segmental instrumentation there is no need for anterior release even for curves in the 70-90 degrees range.

Early experiences with video-assisted thoracoscopic surgery: our first 70 cases

STUDY DESIGN

Prospective consecutive series.

OBJECTIVE

Analysis of the results and outcomes of patients treated with video-assisted thoracoscopic surgery for spinal pathology.

SUMMARY OF BACKGROUND DATA

Video-assisted thoracoscopic surgery is an alternative to open thoracotomy. It has been suggested that the learning curve is substantial. The authors present their early experience in treating a variety of spinal pathologies with this technique.

METHODS

Seventy cases were available at the 2-year follow-up. Video-assisted thoracoscopic surgery with the goal of anterior spinal release and fusion was carried out on patients with the following diagnoses: idiopathic scoliosis, neuromuscular spinal deformity, Scheuermann kyphosis, congenital and infantile scoliosis, neurofibromatosis, Marfan syndrome, postradiation scoliosis, and repair of pseudarthrosis. Three patients had excision of the first rib to treat thoracic outlet syndrome. Two patients had excision of intrathoracic neurofibroma and a benign rib tumor. One had anterior fusion following thoracic spine fracture-dislocation.

RESULTS

The average operative time for the thoracoscopic anterior release with discectomy and fusion procedure was 256 minutes (range 150-405 minutes). The average number of discs excised was 8 (range 4-11 discs). The average operative time per disc was 32.5 minutes (range 20-45 minutes). The average blood loss during the thoracoscopic anterior release with diskectomy and fusion was 285 mL (range 150-405 mL). Final postoperative scoliosis and kyphosis corrections were 68% (range 41-91%) and 90% (range 47-100%), respectively. Complications related to thoracoscopy occurred in 3 patients. All deformity patients had evidence of anterior fusion radiographically.

CONCLUSION

Video-assisted thoracoscopic surgery provides a safe and effective alternative to open thoracotomy in the treatment of thoracic pediatric spinal deformities. The procedure remains time consuming.

The feasibility of anterior thoracoscopic spine surgery in children under 30 kilograms

STUDY DESIGN

A retrospective comparison of pediatric patients weighing less than 30 kg who underwent thoracoscopic anterior spinal release and fusion for deformity correction. This group was compared to two control groups: patients weighing over 30 kg (thoracoscopic) and patients under 30 kg (open).

OBJECTIVE

To determine the efficacy and safety of thoracoscopic anterior spinal release and fusion in small pediatric patients weighing less than 30 kg.

SUMMARY OF BACKGROUND DATA

Recently, thoracoscopic methods have been utilized to perform anterior spinal release/fusion in the treatment of pediatric and adult spinal deformity. The safety, efficacy, and technical challenges of thoracoscopic spinal surgery in small children have not been established.

METHODS

"Small thoracoscopic children," defined as those under 30 kg who had thoracoscopic spinal surgery, are the main focus of this study. They were compared to "large thoracoscopic children" (>30 kg, thoracoscopic surgery) and "small open children" (<30 kg, open surgery). Preoperative, intraoperative, and postoperative parameters were analyzed.

RESULTS

Small thoracoscopic children (n = 33) had greater estimated blood loss/kg body weight (13.6 mL/kg vs. 6.2 mL/kg; P= 0.003), greater chest tube output (27.5 mL/kg vs. 17.1 mL/kg; P= 0.003), and a longer intensive care unit stay (4.2 days vs. 1.5 days; P= 0.001) than did large thoracoscopic children (n = 48). Conversion to an open thoracotomy occurred in one patient from each of the thoracoscopic groups. Small thoracoscopic children required more anesthesia preparation time (79.2 minutes vs. 64.2 minutes; P= 0.002) than the small open children (n = 25). There was no significant difference in estimated blood loss, chest tube output, or intensive care unit stay between these two groups. Additionally, no significant difference was found between the three groups with regard to the number of discs excised, operative time, and total hospital stay.

CONCLUSION

Despite the decreased working space within the chest and difficulties of selective intubation, anterior thoracoscopic surgery for spinal release and fusion can be performed as safely in "small" children as in "large" children; however, additional intraoperative challenges should be anticipated. Although the outcomes were similar in the small thoracoscopic children compared to the small open children, the authors believe that very small patients (under 20 kg) should remain a relative contraindication to thoracoscopic surgery, especially during a surgeon's learning curve.