Thoracoscopic spinal fusion compared with posterior spinal fusion for the treatment of thoracic adolescent idiopathic scoliosis

Minimally Invasive Surgery for Adolescent Idiopathic Scoliosis: A Systematic Review

Background: Minimally invasive surgical (MIS) techniques have gained popularity as a safe and effective alternative to open surgery for degenerative, traumatic, and metastatic spinal pathologies. In adolescent idiopathic scoliosis, MIS techniques comprise anterior thoracoscopic surgery (ATS), posterior minimally invasive surgery (PMIS), and vertebral body tethering (VBT). In the current systematic review, the authors collected and analyzed data from the available literature on MIS techniques in AIS. Methods: The articles were shortlisted after a thorough electronic and manual database search through PubMed, EMBASE, and Google Scholar. Results: The authors included 43 studies for the review; 14 described the outcomes with ATS, 13 with PMIS, and 16 with VBT. Conclusions: While the efficacy of the ATS approach is well-established in terms of comparable coronal and sagittal correction to posterior spinal fusion, the current use of ATS for instrumented fusion has become less popular due to a steep learning curve, high pulmonary and vascular complication rates, implant failures, and increased non-union rates. PMIS is an effective alternative to the standard open posterior spinal fusion, with a steep learning curve and longer surgical time being potential disadvantages. The current evidence, albeit limited, suggests that VBT is an attractive procedure that merits consideration in terms of radiological correction and clinical outcomes, but it has a high complication and re-operation rate, while the most appropriate indications and long-term outcomes of this technique remain unclear.

Defining "successful" treatment outcomes in adolescent idiopathic scoliosis: a scoping review

PURPOSE

Adolescent idiopathic scoliosis (AIS) is the most common type of scoliosis that affects children aged 10-18 years old, manifesting in a three-dimensional spinal deformity. This study aimed to explore outcome measures used in defining AIS treatment success. Particularly, analyzing the extent of qualitative and quantitative (radiographic and quality of life domains) measures to evaluate AIS and whether AIS treatment approaches (surgical, bracing and physiotherapy) influences outcomes used as proxies of treatment success.

METHODS

EMBASE and MEDLINE databases were used to conduct a systematic scoping review with 654 search queries. 158 papers met the inclusion criteria and were screened for data extraction. Extractable variables included: study characteristics, study participant characteristics, type of study, type of intervention approach and outcome measures.

RESULTS

All 158 studies measured quantitative outcomes. 61.38% of papers used radiographic outcomes whilst 38.62% of papers used quantitative quality of life outcomes to evaluate treatment success. Irrespective of treatment intervention utilized, the type of quantitative outcome measure recorded were similar in proportion. Moreover, of the radiographic outcome measures, the subcategory Cobb angle was predominantly used across all intervention approaches. For quantitative quality of life measures, questionnaires investigating multiple domains such as SRS were primarily used as proxies of AIS treatment success across all intervention approaches.

CONCLUSION

This study identified that no articles employed qualitative measures of describing the psychosocial implications of AIS in defining treatment success. Although quantitative measures have merit in clinical diagnoses and management, there is increasing value in using qualitative methods such as thematic analysis in guiding clinicians to develop a biopsychosocial approach for patient care.

Selective Thoracic Fusion for Idiopathic Scoliosis: A Comparison of Three Surgical Techniques with Minimum 5-year Follow-up

STUDY DESIGN

Single-center retrospective review of outcomes among three surgical techniques in the treatment of thoracic idiopathic scoliosis (T-AIS) with a follow-up of at least 5 years.

OBJECTIVE

To investigate how outcomes compare in video-assisted anterior thoracic instrumentation (VATS), all hooks/hook-pedicle screw hybrid instrumentation (HHF), and all pedicle screw instrumentation (PSF) techniques for T-AIS.

SUMMARY OF BACKGROUND DATA

Studies comparing outcomes for anterior versus posterior fusion for T-AIS are few and with short follow-up.

METHODS

Three groups of patients with T-AIS who underwent thoracic fusion were included in this study: 98 patients with mean curve of 49.0° ± 9.5° underwent VATS (Group 1); 44 patients with mean curve of 51.1° ± 7.4° underwent HHF (Group 2); and 47 patients with mean curve of 47.6° ± 9.9° underwent PSF (Group 3). Radiological outcomes were compared at preoperative, and up to 5 years. Surgical outcomes were noted until latest follow-up.

RESULTS

Group 1 had less blood loss, less fusion levels, longer surgical time, and longer hospital stay compared with the other groups (P < 0.01). Groups 1 and 3 were comparable in all time periods with 78.8% and 78.2% immediate curve correction, and 72.9% and 72.1% at 5 years, respectively. Group 2 had lower correction in all time periods (P < 0.0001). Thoracic kyphosis and lumbar lordosis decreased in Group 3, but improved in both Groups 1 and 2 (P < 0.0001). Group 1 had more respiratory complications. The posterior groups had more deep wound infections. Two patients in Group 1 and one patient in Group 2 required revision surgery for implant-related complications. Reoperations for deep wound infections were noted only in the posterior groups.

CONCLUSION

This is the first report comparing 5 year outcomes between anterior and posterior surgery for T-AIS. All three surgical methods resulted in significant and durable scoliosis correction; however, curve correction using HHF was inferior to both VATS and PSF with the latter two groups achieving similar coronal correction. However, VATS involved fewer segments, kyphosis improvement, and no deep wound infection, whereas PSF has less surgical time, shorter hospital stays, and no revision surgery from implant-related complications.Level of Evidence: 3.

Posterior minimally invasive scoliosis surgery versus the standard posterior approach for the management of adolescent idiopathic scoliosis: an updated meta-analysis

Background

Surgical management of adolescent idiopathic scoliosis (AIS) can be performed using standard posterior spinal fusion (PSF) or with a posterior minimally invasive approach. Minimally invasive scoliosis surgery (MISS) has several theoretical advantages, such as less tissue dissection, less blood loss, and earlier recovery. However, the difference in safety and effectiveness between MISS and PSF still needs to be clarified. This updated meta-analysis aimed to compare the outcomes of MISS and standard PSF for the management of AIS.

Methods

A comprehensive literature search of PubMed, EMBASE, MEDLINE, and Cochrane Library without time restriction was performed to identify relevant studies. MISS and PSF were compared in terms of radiographic parameters, estimated blood loss (EBL), blood transfusion rate, operative time (ORT), length of hospital stay (LOS), overall Scoliosis Research Society-22 (SRS-22) score, postoperative pain, and complication rate.

Results

A total of seven studies comprising 767 patients (329 MISS and 438 PSF) with AIS were included. MISS and PSF yielded comparable deformity correction at the last follow-up. There were no significant differences in the overall SRS-22 scores or complication rates between the groups. Nevertheless, greater restoration of thoracic kyphosis (WMD, 2.98; 95% CI 0.58 to 5.37, P = 0.015), less EBL (WMD, −218.76; 95% CI −256.41 to −181.11, P < 0.001), a lower blood transfusion rate (RR, 0.31; 95% CI 0.20 to 0.48, P < 0.001), a shorter LOS (WMD, −1.48; 95% CI −2.48 to −0.48, P = 0.004), less postoperative pain (WMD, 0.57; 95% CI 0.16 to 0.98, P = 0.006), and a longer ORT (WMD, 84.85; 95% CI 33.30 to 136.40, P = 0.001) were observed in the MISS group.

Conclusion

Despite its inherent technical challenges, MISS is a feasible and effective alternative to standard PSF for AIS patients with moderate and flexible curves. MISS was associated with adequate deformity correction, better restoration of sagittal alignment, less EBL, fewer transfusions, shorter LOS, and better pain management compared to PSF. Further research is required to determine the detailed indications for the MISS procedure.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13018-022-02954-4.

Minimally invasive surgery versus standard posterior approach for Lenke Type 1-4 adolescent idiopathic scoliosis: a multicenter, retrospective study

PURPOSE

To compare the safety and efficacy of posterior minimally invasive surgery (MIS) to standard posterior spinal fusion (PSF) surgery for Lenke Type 1-4 adolescent idiopathic scoliosis (AIS).

METHODS

This multicenter retrospective study enrolled 112 patients with Lenke Type 1-4 AIS who treated with MIS (n = 64) or PSF (n = 48) between March 2007 and January 2015. Coronal and sagittal parameters were evaluated before surgery, immediately after surgery, and at the last follow-up. Operative time, level of fusion, intraoperative blood loss, blood transfusion, and intraoperative radiation exposure were recorded. 22-item Scoliosis Research Society questionnaire (SRS-22) was applied for assessment of life quality. The accuracy of pedicle screw placement was assessed according to postoperative computed tomography images, and the complications were collected in follow-up period.

RESULTS

The baseline characteristics of 2 groups were matched. There was no significant difference between 2 groups in terms of radiographic parameters immediately after surgery and at the last follow-up. The MIS group had significantly longer operative time, more level of fusion, less intraoperative blood loss, and lower blood transfusion rate (p < 0.001). The evaluation of pain using SRS-22 showed significantly lower score in MIS group (p < 0.05). No significant difference was found between 2 groups in terms of accuracy of pedicle screw placement and complications.

CONCLUSION

Posterior MIS is a safe and effective alternative to standard open approach for Lenke Type 1-4 AIS patients with curves < 70° and reasonable flexibility. Mid-term results showed MIS had the advantages of less blood loss and pain with more fusion segments.

Effectiveness and safety of surgical interventions for treating adolescent idiopathic scoliosis: a Bayesian meta-analysis

BACKGROUND

Adolescent idiopathic scoliosis (AIS) is the most common form of spinal deformity in children and adolescents which presents as complex three-dimensional (3D) deformity of the spine and rib cage. This study aimed to estimate the effectiveness and safety of surgical interventions for AIS using Bayesian meta-analysis.

METHODS

The PubMed, EMBASE, and Cochrane Controlled Register of Trials were searched through Oct 1, 2019, without language restrictions. Relevant studies evaluating combined effectiveness and safety of surgical interventions for AIS were included according to eligibility criteria. The primary outcome measures included pulmonary function (change of absolute forced vital capacity and forced expiratory volume in 1 second from pre-operation to post-operation) and incidence of complications. The secondary outcome measure was change of Cobb angle from pre-operation to post-operation. Data was pooled using a random effects model in pairwise meta-analysis. Bayesian meta-analysis combined direct and indirect evidence using a Bayesian framework.

RESULTS

Twenty-eight case-controlled studies with totally 1970 participants were included. This Bayesian meta-analysis combining direct and indirect evidences indicated that posterior fusion with instrumentation without thoracoplasty (PSF) had the highest probability to achieve better pulmonary function and lower complication rate; video assisted anterior fusion with instrumentation without thoracoplasty (VAT) had the highest probability to obtain better Cobb angle correction based on analysis of rank probability.

CONCLUSION

This Bayesian meta-analysis demonstrated that PSF had the highest probability to achieve better post-surgical pulmonary function and lower complication rate, which gives a practical recommendation of PSF as a primary surgical treatment for AIS. The results also support statistics that current surgeries adopted more PSF but less open anterior approach surgery and thoracoplasty. More research work is required to address the effectiveness and safety of VAT for treating AIS more convincingly.

Thoracoscopic Anterior Instrumentation and Fusion as a Treatment for Adolescent Idiopathic Scoliosis: A Systematic Review of the Literature

STUDY DESIGN

A systematic review and meta-analysis on thoracoscopic anterior instrumentation and fusion as a treatment for adolescent idiopathic scoliosis (AIS).

OBJECTIVE

The goal of this study is to determine the current status of thoracoscopic instrumentation and fusion as a treatment for AIS.

SUMMARY OF BACKGROUND DATA

Traditional surgical techniques for AIS have been open anterior thoracotomy with instrumentation and posterior spinal fusion and instrumentation. With the growing clinical interest in growth modulation surgeries, such as vertebral body tethering, there is a resurgence of interest in a thoracoscopic technique.

METHODS

The most commonly used medical databases (PubMed, Medline, EMBASE, CINAHL, and the Cochrane library) were searched up to November 2016 using the search terms VATS, thoracoscopic scoliosis, and thoracoscopic scoliosis instrumentation.

RESULTS

Thirteen studies met the strict inclusion criteria. Five hundred thirty patients were reported: 81.7% females, with the majority diagnosed as AIS. The mean operative time was 371.5 minutes, mean blood loss of 502.85 mL, and mean hospital stay of 5.9 days. Mean preoperative curve magnitude was 52.9°; postoperative curve magnitude was 17.9°, with a correction of 62.7%. Number of levels instrumented was 6.3, pulmonary function tests returned to preoperative values by 2 years postoperation, and the complication rate was 21.3%. Compared to thoracotomy, VATS had similar complication rates, blood loss, operation theater time, curve correction, and number of fused levels. Compared to posterior fusion, VATS has higher complication rates and operation theater time. Blood loss and percentage correction were similar. VATS had a smaller number of fused segments.

CONCLUSIONS

Advantages include less invasive, excellent curve correction, few levels fused, good satisfaction, and no long-term effect on pulmonary function. Drawbacks are increased operative time and incidence of pulmonary complications. With appropriate surgeon training and careful patient selection, this technique offers an acceptable alternative to the more traditional procedures.

LEVEL OF EVIDENCE

Level II.

Long-term outcome of posterior spinal fusion for the correction of adolescent idiopathic scoliosis

Background

Adolescent idiopathic scoliosis (AIS) is the most common form of idiopathic scoliosis, and surgery is considered as one of the therapeutic options. However, it is associated with a variety of irreversible complications, in spite of the benefits it provides. Here, we evaluated the long-term outcome of posterior spinal fusion (PSF) of AIS to shed more light on the consequences of this surgery.

Methods

In a cross-sectional study, a total of 42 AIS patients who underwent PSF surgery were radiographically and clinically inspected for the potential post-operative complications. Radiographic assessments included the device failure, union status, and vertebral tilt below the site of fusion. Clinical outcomes were evaluated using the Oswestry disability index (ODI) and visual analogue scale (VAS).

Results

The mean age of the surgery was 14.4 ± 5.1 years. The mean follow-up of the patients was 5.6 ± 3.2 years. Complete union was observed in all patients, and no device failure was noticed. Pre- and post-operative vertebral tilt below the site of fusion were 11.12° ± 7.92° and 6.21° ± 5.73°, respectively (p < 0.001). The mean post-operative ODI was 16.7 ± 9.8. The mean post-operative VAS was 2.1 ± 0.7. ODI value was positively correlated with follow-up periods (p = 0.04, r = 0.471). New degenerative disc disease (DDD) was observed in 6 out of 37 (16%) patients.

Conclusion

In spite of the efficacy and safety of PSF surgery of AIS, it might result in irreversible complications such as DDD. Moreover, the amount of post-operative disability might increase over the time and should be discussed with the patients.

Pediatric spine imaging post scoliosis surgery

Many orthopedic articles describe advances in surgical techniques and implants used in pediatric scoliosis surgery. However, even though postoperative spine imaging constitutes a large portion of outpatient musculoskeletal pediatric radiology, few, if any, radiology articles discuss this topic. There has been interval advancement over the last decades of the orthopedic procedures used in the treatment of spinal scoliosis in adolescents with idiopathic scoliosis. The goal of treatment in these patients is to stop the progression of the curve by blocking the spinal growth and correcting the deformity as much as possible. To that end, the authors in this paper discuss postoperative imaging findings of Harrington rods, Luque rods, Luque-Galveston implants and segmental spinal fusion systems. Regarding early onset scoliosis, the guiding principles used for adolescent idiopathic scoliosis do not apply to a growing spine because they would impede lung development. As a result, other devices have been developed to correct the curve and to allow spinal growth. These include spine-based growing rods, vertically expandable prosthetic titanium rods (requiring repetitive surgeries) and magnetically controlled growing rods (with a magnetic locking/unlocking system). Other more recent systems are Shilla and thoracoscopic anterior vertebral body tethering, which allow guided growth of the spine without repetitive interventions. In this paper, we review the radiologic appearances of different orthopedic implants and techniques used to treat adolescent idiopathic scoliosis and early onset scoliosis. Moreover, we present the imaging findings of the most frequent postoperative complications.

Resource Utilization in Adolescent Idiopathic Scoliosis Surgery: Is There Opportunity for Standardization?

INTRODUCTION

Recent healthcare reforms have raised the importance of cost and value in the management of disease. Value is a function of benefit and cost. Understanding variability in resources utilized by individual surgeons to achieve similar outcomes may provide an opportunity for cutting costs though greater standardization. The purpose of this study is to evaluate differences in use of implants and hospital resources among surgeons performing adolescent idiopathic scoliosis (AIS) surgery.

METHODS

A multicenter prospective AIS operative database was queried. Patients were matched for Lenke curve type and curve magnitude, resulting in 5 surgeons and 35 matched groups (N = 175). Mean patient age was 14.9 years and curve magnitude 50°. Parameters of interest were compared between surgeons via ANOVA and Bonferroni pairwise comparison.

RESULTS

There was no significant difference in percentage curve correction or levels fused between surgeons. Significant differences between surgeons were found for percentage posterior approach, operative time, length of stay (LOS), estimated blood loss (EBL), cell saver transfused, rod material, screw density, number of screws, use of antifibrinolytics, and cessation of intravenous analgesics. Despite differences in EBL and cell saver transfused, there were no differences in allogenic blood (blood bank) use.

CONCLUSION

Significant variability in resource utilization was noted between surgeons performing AIS operations, although radiographic results were uniform. Standardization of resource utilization and cost containment opportunities include implant usage, rod material, LOS, and transition to oral analgesics, as these factors are the largest contributors to cost in AIS surgery.

Evaluating the Change in Axial Vertebral Rotation Following Thoracoscopic Anterior Scoliosis Surgery Using Low-Dose Computed Tomography

BACKGROUND CONTEXT

In recent years, there has been increasing appreciation of the need to treat scoliosis as a three-dimensional deformity.

PURPOSE

Assessment of surgical strategies and outcomes should consider not only the coronal plane correction but also derotation of the transverse plane deformity that can affect trunk appearance.

STUDY DESIGN

This study included a cohort of 29 female adolescent idiopathic scoliosis patients who received thoracoscopic single rod anterior fusion (TASF) surgery. This study used pre- and postoperative low-dose computed tomographic (CT) scans to accurately measure apical axial vertebral rotation (AVR).

METHODS

The pre- and postoperative values for clinically measured coronal Cobb correction and rib hump correction as well as AVR were compared to determine whether these values improved postoperatively. There are no conflicts of interest to report for authors of this investigation.

RESULTS

As expected, statistically significant reductions in coronal Cobb angle (mean preoperative Cobb 51°, reducing to 24° at the two-year follow-up) and rib hump (mean preoperative rib hump 15°, reducing to 7° at two-year follow-up) were achieved. The mean reduction in apical AVR measured using CT was only 3° (mean preoperative AVR 16°, reducing to 13° at two-year follow-up), which was statistically but not clinically significant. Significant correlations were found between Cobb angle and rib hump, between Cobb angle and AVR, and between AVR and rib hump, suggesting that patients with greater coronal Cobb correction also achieve better derotation with this surgical procedure.

CONCLUSIONS

The historical low-dose CT data set permitted detailed three-dimensional assessment of the deformity correction that is achieved using thoracoscopic anterior spinal fusion for progressive adolescent idiopathic scoliosis.

Minimally Invasive Surgery in Patients With Adolescent Idiopathic Scoliosis: Is it Better than the Standard Approach? A 2-Year Follow-up Study

STUDY DESIGN

This is a retrospective controlled study.

OBJECTIVE

To compare the safety and efficacy of minimally invasive surgery (MIS) for the surgical management of adolescent idiopathic scoliosis (AIS) to the standard open posterior approach (PSF).

SUMMARY OF BACKGROUND DATA

MIS approaches offer the potential to reduce soft-tissue trauma, intraoperative blood loss, and surgical-site infection. Thus far, MIS has been successfully utilized for the surgical correction of multilevel spine pathology in adults. It is not yet known if these results can be replicated in the surgical management of AIS.

MATERIALS AND METHODS

Seven MIS patients were compared with 15 PSF patients using minimum 2-year follow-up data. Parameters studied included preoperative patient and deformity characteristics, perioperative details, extent of deformity correction, and complications. Data were compared using Mann-Whitney tests for continuous variables and Fisher exact tests for categorical variables.

RESULTS

The MIS and PSF groups were similar for all preoperative characteristics collected (P>0.05). MIS patients had fewer fixation points (P=0.015), but a longer median operative time (P=0.011). There was no significant difference in estimated blood loss (EBL) (P=0.051), EBL/fixation point (P=0.204), or amount of fluids administered (P=0.888). Postoperative recovery did not differ between the 2 groups in number of intensive care unit days (P=0.362), length of hospital stay (P=0.472), time to mobilization (P=1.00), Visual Analogue Scale pain scores (P=0.698), or patient-controlled analgesia (P=1.00). The MIS technique had similar deformity correction, screw placement accuracy, and fusion status when compared with the PSF group. MIS patients had lower blood transfusion rate (P=0.02), shorter fusion (P=0.046) and fewer pedicle screws (P=0.015).

CONCLUSIONS

The short-term advantages seen in MIS for adult scoliosis were not as obvious in our series. We found similar deformity correction and adequate fusion, however shortcomings related to learning curve, and instrumentation persist. MIS surgery is an innovative treatment for AIS that is technically feasible with significantly lower transfusion rate, shorter fusion lenghts and lesser pedicle screw fixation. Despite these advanatges, its role in AIS is currently difficut to define.

Partial Intervertebral Fusion Secures Successful Outcomes After Thoracoscopic Anterior Scoliosis Correction: A Low-Dose Computed Tomography Study

STUDY DESIGN

Retrospective review of prospectively collected data.

OBJECTIVES

To analyze intervertebral (IV) fusion after thoracoscopic anterior spinal fusion (TASF) and explore the relationship between fusion scores and key clinical variables.

SUMMARY OF BACKGROUND INFORMATION

TASF provides comparable correction with some advantages over posterior approaches but reported mechanical complications, and their relationship to non-union and graft material is unclear. Similarly, the optimal combination of graft type and implant stiffness for effecting successful radiologic union remains undetermined.

METHODS

A subset of patients from a large single-center series who had TASF for progressive scoliosis underwent low-dose computed tomographic scans 2 years after surgery. The IV fusion mass in the disc space was assessed using the 4-point Sucato scale, where 1 indicates <50% and 4 indicates 100% bony fusion of the disc space. The effects of rod diameter, rod material, graft type, fusion level, and mechanical complications on fusion scores were assessed.

RESULTS

Forty-three patients with right thoracic major curves (mean age 14.9 years) participated in the study. Mean fusion scores for patient subgroups ranged from 1.0 (IV levels with rod fractures) to 2.2 (4.5-mm rod with allograft), with scores tending to decrease with increasing rod size and stiffness. Graft type (autograft vs. allograft) did not affect fusion scores. Fusion scores were highest in the middle levels of the rod construct (mean 2.52), dropping off by 20% to 30% toward the upper and lower extremities of the rod. IV levels where a rod fractured had lower overall mean fusion scores compared to levels without a fracture. Mean total Scoliosis Research Society (SRS) questionnaire scores were 98.9 from a possible total of 120, indicating a good level of patient satisfaction.

CONCLUSIONS

Results suggest that 100% radiologic fusion of the entire disc space is not necessary for successful clinical outcomes following thoracoscopic anterior selective thoracic fusion.

Does the Quality of Life in Operated Patients with Adolescent Idiopathic Scoliosis correspond with the Radiographic Parameters?

Objectives: Traditionally, scoliosis surgery is aimed at attaining a fused, balanced and painless spine. With improvement in surgical and instrumentation techniques, spine surgeons strive to achieve higher degree of Cobb’s angle and rib hump correction with the idea of greater patient satisfaction. The aim of this study was to determine the patients’ satisfaction using SRS-22 questionnaire and their correlations with the radiographic changes.

Materials and methods: A prospective study was conducted in a tertiary referral cen re using the Scoliosis Research Society-22 (SRS-22) questionnaire during the patients’ annual follow up, betwee February to April 2014. Thirtyseven patients who met the inclusion criteria were enrolled. Results: The mean pre-operative Cobb’s angles were 57.8o ± 12.7o and mean post-operative angle of 20.0o ± 10.4o, resulting in average correction of 65.9 ± 14.4%. Mean preoperative rib hump was 61.1 ± 15.4 mm with mean postoperative rib hump of 15.8 ± 17.8 mm, resulting in average reduction of 77.7 ± 23.7%. Mean of post-operative total SRS score was 4.1 ± 0.5. Using Spearman rank correlation, the percentage of Cobb’s angle correction versus the SRS-22 score showed correlation of 0.17 (P=0.33) while the percentage of rib hump reduction versus SRS-22 score showed a correlation of 0.11 (P=0.53).

Conclusion: In this study, the average total SRS-22 score was 4.1 ± 0.5 (range, 3.1-4.9) post-operatively indicating very high satisfaction rate overall. Despite attempts at greater curve correction and rib hump reduction, there is no direct correlation between patient satisfaction and radiographic parameters.

Long-term impact of pre-operative physical rehabilitation protocol on the 6-min walk test of patients with adolescent idiopathic scoliosis: A randomized clinical trial

BACKGROUND

Monitored physical activities in patients with adolescent idiopathic scoliosis (AIS) have been shown to improve physical performance, endurance and cardiopulmonary function and may be assessed by the 6-min walk test (6MWT). We aimed to evaluate the long-term results of the 6MWT after a rehabilitation protocol employed before surgical correction for AIS.

METHODS

This prospective randomized clinical trial studied the impact of a 4-month pre-operative physical rehabilitation protocol on post-operative cardiopulmonary function and physical endurance, by using the 6MWT, in patients with AIS submitted to surgical correction, comparing them to matched controls without physical rehabilitation. Studied variables were heart and respiratory rate, systolic and diastolic blood pressure, peripheral blood oxygen saturation, Borg score, and distance walked. Patients were assessed at baseline, after 4 months of rehabilitation, and 3, 6 and 12 months post-operatively.

RESULTS

A total of 50 patients with AIS were included in the study and allocated blindly, by simple randomization, into either one of the two groups, with 25 patients each: study group (pre-operative physical rehabilitation) and control group. The physical rehabilitation protocol promoted significant progressive improvement in heart and respiratory rate, peripheral blood oxygen saturation, distance walked, and level of effort assessed by the Borg scale after surgery.

CONCLUSIONS

Post-surgical recovery, evaluated by 6MWT, was significantly better in patients who underwent a 4-month pre-operative physical rehabilitation protocol.

Preoperative factors predicting intraoperative blood loss in female patients with adolescent idiopathic scoliosis

In this article, a retrospective analysis of 161 female patients with adolescent idiopathic scoliosis (AIS) is performed who underwent posterior correction and fusion using all-pedicle screw instrument.The aim of this article is to find out preoperative factors that influence intraoperative blood loss (IOBL) in female patients with AIS.The IOBL in posterior correction and fusion surgery for patients with idiopathic scoliosis greatly varies. The variables affecting the IOBL also greatly vary among different studies.Medical records of all female patients with AIS who underwent posterior correction and fusion operations using the all-pedicle screw system in our hospital from January 2012 to January 2014 were reviewed. Patients with irregular menstruation, who underwent osteotomy, and using coagulants were excluded. Preoperative clinical data, including patient age, height, weight, Risser sign, day after last menstruation, major curve Cobb angle, fulcrum-bending Cobb angle, curve flexibility index, sagittal thoracic Cobb angle, sagittal lumbar Cobb angle, albumin, hemoglobin, platelet, activated partial thromboplastic time (APTT), prothrombin time, thrombin time, fibrinogen, fusion level, menstrual phase, and blood type, were collected. Data were further analyzed using multiple linear regression with forward elimination.A total of 161 patients were included in this study. The mean IOBL was 933.98 ± 158.10 mL (500-2000 mL). Forward selection showed that fulcrum-bending Cobb angle, fusion level, Risser sign, APTT, fibrinogen, and menstrual phase were the preoperative factors that influenced the IOBL in female patients with AIS. Equation of IOBL was built by multiple linear regression: IOBL = -966.228 + 54.738 Risser sign + 18.910 fulcrum-bending Cobb angle + 114.737 fibrinogen + 21.386 APTT - 71.312 team 2 - 177.985 team 3 - 165.082 team 4 + 53.470 fusion level. R = 0.782.Operation for patients with AIS was featured by large IOBL. Large fulcrum-bending Cobb angle, the number of level fused, higher Risser sign, high APTT, high preoperative blood fibrinogen concentration, and premenstrual phase predicted higher IOBL.

How to improve shoulder balance in the surgical correction of double thoracic adolescent idiopathic scoliosis

STUDY DESIGN

A retrospective comparative study.

OBJECTIVE

To evaluate the shoulder balance resulting from the correction of double thoracic adolescent idiopathic scoliosis (AIS) comparing rod derotation (RD) with direct vertebral rotation (DVR) and RD only after pedicle screw instrumentations.

SUMMARY OF BACKGROUND DATA

This is the first report on the effect of DVR on the shoulder balance using segmental pedicle screw instrumentation in the treatment of double thoracic AIS with minimum 5-year follow-up.

METHODS

Patients with double thoracic AIS (n = 57) were treated by fusing both thoracic curves with RD and DVR (n=35), or RD (n=22) methods and retrospectively studied with a minimum 5 years of follow-up.

RESULTS

In the RD with DVR group, the preoperative proximal thoracic curve of 40.2° improved to 17.9° postoperatively and 19.9° at the last follow-up. In the RD group, the preoperative proximal thoracic curve of 37.5° improved to 22.4° postoperatively and 23.2° at the last follow-up. In the RD with DVR group, the preoperative distal thoracic curve of 56.6° improved to 16.1° postoperatively and 16.7° at the last follow-up. In the RD group, the preoperative distal thoracic curve of 50.6° improved to 17.8° postoperatively and 18.2° at the last follow-up. In the RD with DVR group, the average preoperative shoulder height difference of 16.3 mm had improved to 7.2 mm postoperatively and was 7.0 mm at the last follow-up. In the RD group, the average preoperative shoulder height difference of 15.1 mm had changed to 7.5 mm postoperatively and was 7.3 mm at the last follow-up.

CONCLUSION

Shoulder balance had not significantly improved even with additional correction method of DVR using segmental pedicle screw instrumentation in double thoracic AIS. The proximal thoracic curve was rigid and corrected less in both groups. Therefore, less correction of the distal thoracic curve effectively achieves better shoulder balance.

LEVEL OF EVIDENCE

3.

Surgical treatment of Lenke 1 main thoracic idiopathic scoliosis: results of a prospective, multicenter study

STUDY DESIGN

Prospective, consecutive, nonrandomized, multicenter study.

OBJECTIVE

The purpose of this study was to compare the outcomes of idiopathic scoliosis treatment for Lenke 1 curves with 3 treatment approaches.

SUMMARY OF BACKGROUND DATA

Surgical treatment options for Lenke 1 or primary main thoracic curve pattern in adolescent idiopathic scoliosis include thoracoscopic anterior spinal fusion, open anterior spinal fusion, and posterior spinal fusion (PSF) and instrumentation procedures.

METHODS

This was a prospective, consecutive, nonrandomized, multicenter study of surgical correction in adolescent idiopathic scoliosis. Patients with Lenke type 1 curve patterns from 7 sites were enrolled in this minimum 2-year follow-up study. Changes in pre- to postoperative radiographs, pulmonary function tests, Scoliosis Research Society questionnaire scores, and trunk rotation measures were compared.

RESULTS

A total of 149 patients (age: 14.5 ± 2 yr) were included (91% follow-up at 2 yr). The 3 groups were similar preoperatively in thoracic and lumbar curve size. There were 55 patients with thoracoscopic anterior spinal fusion, 17 patients with open anterior spinal fusion, and 64 patients with PSF. The fusion included on average 3 to 4 more levels in PSF than the 2 anterior approaches (P ≤ 0.001). Surgical time tended to be greater in the anterior groups by approximately 2 to 3 hours; however, blood loss was greatest with PSF. At 2 years, all 3 approaches showed similar improvements in the thoracic Cobb angle, coronal balance, the lumbar Cobb angle, Scoliosis Research Society questionnaire scores, and trunk rotation measures. The PSF approach resulted in overall reduction in kyphosis compared with the anterior approaches. Postoperative hyperkyphosis was an issue only in the 2 anterior groups. Major complication rates were similar.

CONCLUSION

All 3 approaches resulted in similarly satisfactory outcomes for the majority of patients with specific advantages to each technique. The patients with PSF had more levels fused, yet with the shortest operative time. The thoracoscopic anterior spinal fusion group had the smallest incisions and the lowest requirement for transfusion. The open anterior spinal fusion group had a modest loss of pulmonary function without any clear advantages compared with the other 2 groups.

LEVEL OF EVIDENCE

2.

Anterior surgery for adolescent idiopathic scoliosis

Anterior open scoliosis surgery using the dual rod system is a safe and rather effective procedure for the correction of scoliosis (50-60 %). Thoracic hypokyphosis and rib hump correction with open anterior rather than posterior instrumentation appear to be the better approaches, although the latter is somewhat controversial with current posterior vertebral column derotation devices. In patients with Risser grade 0, hyperkyphosis and adding-on may occur with anterior thoracic spine instrumentation. Anterior thoracoscopic instrumentation provides a similar correction (65 %) with good cosmetic outcomes, but it is associated with a rather high risk of instrumentation (pull-out, pseudoarthrosis) and pulmonary complications. Approximately 80 % of patients with adolescent idiopathic scoliosis (AIS) curves of >70° have restrictive lung disease or smaller than normal lung volumes. AIS patients undergoing anterior thoracotomy or anteroposterior surgery will demonstrate a significant decrease in percentage of predicted lung volumes during follow-up. The thoracoabdominal approach and thoracoscopic approach without thoracoplasty do not produce similar changes in detrimental lung volume. In patients with severe AIS (>90°), posterior-only surgery with TPS provides similar radiographic correction of the deformity (44 %) with better pulmonary function outcomes than anteroposterior surgery. Vascular spinal cord malfunction after segmental vessel ligation during anterior scoliosis surgery has been reported. Based on the current literature, the main indication for open anterior scoliosis instrumentation is Lenke 5C thoracolumbar or lumbar AIS curve with anterior instrumentation typically between T11 and L3.

Posterior instrumentation and fusion

The purpose of surgery for adolescent idiopathic scoliosis, which characteristically includes thoracic hypokyphosis and all three columns of the spine, is the achievement of a balanced spine while preserving as many motion segments as possible and avoiding neurologic damage. Many approaches have been defined in the treatment of this common disease. Posterior-only surgery, instrumentation and fusion have become the preferred technique in many centers throughout the world due to simplicity of approach, decreased risk of certain complications and the correction power of pedicle screws. This review attempts to summarize the advantages and disadvantages related to posterior instrumentation and fusion in adolescent idiopathic scoliosis.

Current concepts and controversies on adolescent idiopathic scoliosis: Part II

A new era in the surgical treatment of adolescent idiopathic scoliosis (AIS) opened with the introduction of pedicle screw instrumentation, which provides 3-column vertebral fixation and allows major deformity correction on the coronal, sagittal, and axial planes. A steep learning curve can be expected for spinal surgeons to become familiar with pedicle screw placement and correction techniques. Potential complications including injury to adjacent neural, vascular, and visceral structures can occur due to screw misplacement or pull-out during correction maneuvers. These major complications are better recognized as pedicle screw techniques become more popular and may result in serious morbidity and mortality. Extensive laboratory and clinical training is mandatory before pedicle screw techniques in scoliosis surgery are put to practice. Wider application, especially in developing countries, is limited by the high cost of implants. Refined correction techniques are currently developed and these utilize a lesser number of pedicle anchors which are strategically positioned to allow optimum deformity correction while reducing the neurological risk, surgical time, and blood loss, as well as instrumentation cost. Such techniques can be particularly attractive at a time when cost has major implications on provision of health care as they can make scoliosis treatment available to a wider population of patients. Pedicle screw techniques are currently considered the gold standard for scoliosis correction due to their documented superior biomechanical properties and ability to produce improved clinical outcomes as reflected by health-related quality-of-life questionnaires. Ongoing research promises further advances with the future of AIS treatment incorporating genetic counseling and possibly fusionless techniques.

Anterior versus posterior approach in 3D correction of adolescent idiopathic thoracic scoliosis: a meta-analysis

PURPOSE

Systematic review was conducted to compare effectiveness and safety of anterior and posterior surgical approach in 3D correction of adolescent idiopathic thoracic scoliosis.

METHODS

Data sources were MEDLINE and SCOPUS databases. We included studies on the use of either anterior or posterior instrumentation, or their combination, in surgical correction of adolescent idiopathic thoracic scoliosis, with at least 10 enrolled patients, aged less than 20 years at the time of surgery, and a follow-up of at least 24 months. A study was eligible if it reported the number of patients, mean estimate and dispersion of three key outcome measures (frontal and sagittal Cobb angle, apical vertebra rotation according to Perdriolle) at three measurement points (preoperatively, postoperatively, at follow-up). The quality of studies was assessed using the scale by Pilkington.

RESULTS

Although 24 articles met the inclusion criteria, no randomized controlled trials (RCT) was identified. None of the articles was of high quality. Both instrumentations provided a similar degree of reduction of frontal Cobb angle. Long-term effects of surgical correction on the sagittal Cobb angle seemed to be more stable in patients treated by posterior approach, while the anterior approach was more effective in the reduction of apical vertebral rotation. The surgery parameters were more favorable for anterior approach, particularly for the number of fused vertebrae.

CONCLUSIONS

Although the available evidence favors neither of the two approaches, our study revealed several important issues: the reports are heterogeneous and provide incomplete relevant information. High quality studies, particularly RCT, are called for.

LEVEL OF EVIDENCE

Level II.

Secondary curve behavior in Lenke type 1C adolescent idiopathic scoliosis after thoracoscopic selective anterior thoracic fusion

STUDY DESIGN

Analysis of a case series of 24 patients with Lenke 1C adolescent idiopathic scoliosis (AIS) receiving selective thoracoscopic anterior scoliosis correction.

OBJECTIVE

To report the behavior of the compensatory lumbar curve in a group of patients with Lenke IC AIS after thoracoscopic anterior scoliosis correction and to compare the results of this study with previously published data.

SUMMARY OF BACKGROUND DATA

Several prior studies have reported spontaneous lumbar curve correction for both anterior and posterior selective fusions in patients with Lenke 1C/King-Moe 2; however, to our knowledge no previous studies have reported outcomes of thoracoscopic anterior correction for this curve type.

METHODS

All patients with AIS with a curve classification of Lenke 1C and a minimum of 24-month follow-up were obtained from a consecutive series of 190 patients with AIS who underwent thoracoscopic anterior instrumented fusion. Cobb angles of the major curve, instrumented levels, compensatory lumbar curve, and T5-T12 kyphosis were recorded, as well as coronal spinal balance, T1 tilt angle, and shoulder balance. All radiographical parameters were measured before surgery and at 2, 6, 12, and 24 months after surgery.

RESULTS

Twenty-four female patients with right thoracic curves had a mean thoracic Cobb angle of 53.0° before surgery, decreasing to 24.9° 2 years after surgery. The mean lumbar compensatory Cobb angle was 43.5° before surgery, spontaneously correcting to 25.4° 2 years after surgery, indicating balance between the thoracic and lumbar scoliotic curves. The lumbar correction achieved (41.8%) compares favorably to previous studies.

CONCLUSION

Selective thoracoscopic anterior fusion allows spontaneous lumbar curve correction and achieves coronal balance of main thoracic and compensatory lumbar curves, good cosmesis, and patient satisfaction. Correction and balance are maintained 24 months after surgery.

CT and radiographic analysis of sagittal profile changes following thoracoscopic anterior scoliosis surgery

Background

Previous studies report an increase in thoracic kyphosis after anterior approaches and a flattening of sagittal contours following posterior approaches. Difficulties with measuring sagittal parameters on radiographs are avoided with reformatted sagittal CT reconstructions due to the superior endplate clarity afforded by this imaging modality.

Methods

A prospective study of 30 Lenke 1 adolescent idiopathic scoliosis (AIS) patients receiving selective thoracoscopic anterior spinal fusion (TASF) was performed. Participants had ethically approved low dose CT scans at minimum 24 months after surgery in addition to their standard care following surgery. The change in sagittal contours on supine CT was compared to standing radiographic measurements of the same patients and with previous studies. Inter-observer variability was assessed as well as whether hypokyphotic and normokyphotic patient groups responded differently to the thoracoscopic anterior approach.

Results

Mean T5-12 kyphosis Cobb angle increased by 11.8 degrees and lumbar lordosis increased by 5.9 degrees on standing radiographs two years after surgery. By comparison, CT measurements of kyphosis and lordosis increased by 12.3 degrees and 7.0 degrees respectively. 95% confidence intervals for inter-observer variability of sagittal contour measurements on supine CT ranged between 5-8 degrees. TASF had a slightly greater corrective effect on patients who were hypokyphotic before surgery compared with those who were normokyphotic.

Conclusions

Restoration of sagittal profile is an important goal of scoliosis surgery, but reliable measurement with radiographs suffers from poor endplate clarity. TASF significantly improves thoracic kyphosis and lumbar lordosis while preserving proximal and distal junctional alignment in thoracic AIS patients. Supine CT allows greater endplate clarity for sagittal Cobb measurements and linear relationships were found between supine CT and standing radiographic measurements. In this study, improvements in sagittal kyphosis and lordosis following surgery were in agreement with prior anterior surgery studies, and add to the current evidence suggesting that anterior correction is more capable than posterior approaches of addressing the sagittal component of both the instrumented and adjacent non instrumented segments following surgical correction of progressive Lenke 1 idiopathic scoliosis.

Use and outcomes of wound drain in spinal fusion for adolescent idiopathic scoliosis

STUDY DESIGN

A multicenter retrospective analysis.

OBJECTIVE

To evaluate outcomes of closed-suction wound drainage after posterior spinal fusion with instrumentation for adolescent idiopathic scoliosis and to identify surgeon patterns of drain use in this cohort.

SUMMARY OF BACKGROUND DATA

There is little evidence on the use of drains in spinal surgery, particularly for repair of adolescent idiopathic scoliosis. Studies on hip and knee arthroplasty suggest no advantage to draining. There are few published reports on surgeon technique and rationale for drain use in spinal surgery.

METHODS

Patients were divided into drain and no drain cohorts and followed for 2 years. Primary outcome was complication rate. A separate survey was conducted from surgeons in the Spinal Deformity Study Group to evaluate drain practice patterns.

RESULTS

There were 324 drained and 176 undrained patients. Complication rate did not differ between the drain and no drain cohorts in any of the 4 categories (wound infection, neural injury, other infection, and other complication) at any time (all P > 0.1). More drained patients received postoperative transfusions compared with those without a drain (43% vs. 22%, P < 0.001). Of the 50 surgeons in the group, 36 used drains. Half of these did so out of habit. Surgeons tended to place deep drains with bulb suction, without drain manipulation. Half removed drains on the basis of output, whereas half removed them after 1 to 3 days.

CONCLUSION

More patients tended to receive wound drains than not receive wound drains. Drains did not impact complication rate and drained patients received more blood product. There are no universal criteria for draining and practice patterns vary widely.

Anterior short correction in thoracic adolescent idiopathic scoliosis with mini-open thoracotomy approach: prospective clinical, radiological and pulmonary function results

INTRODUCTION

This is a prospective study of adolescent patients in whom idiopathic thoracic scoliosis was corrected by short anterior fusion through a mini-open thoracotomy approach. Clinical, radiological and pulmonary function results of minimal 2-year (2-6) follow-up are presented.

MATERIALS AND METHODS

Consecutive 62 patients with Lenke 1 and 2 curves, having main thoracic scoliosis of up to 75°, were prospectively included. The shoulder imbalance in Lenke 2 patients was less than 20 mm. Thoracic scoliosis was corrected by short anterior fusion. The thoracic spine was exposed by an 8-cm mini-open thoracotomy incision. The operation technique and choosing of fusion levels are thoroughly described. Complete 360° discectomies and convex side vertebral endplates osteotomies are essential for deformity corrections with short fusions. Single-rod 5.5-mm titanium implants were used. The age at the time of operation was mean 15.2 years; 56 patients had a single thoracic curve and 6 patients had a double thoracic curve. There were almost equal numbers of patients with lumbar modifier A, B or C. The average length of fusion was 5.5 (4-7) vertebrae. The average length of fusion was 3.5 (2-6) vertebrae shorter than the average curve length.

RESULTS

The instrumented thoracic curves improved by 58.3% at 6 weeks and 56.3% at the last follow-up. Apex thoracic vertebral rotation improved by 73.78% at 6 weeks and 76.24% at the last follow-up. The non-instrumented upper thoracic curve improved by 25% in double thoracic scoliosis, where the mid-thoracic curve was selectively fused, and the non-instrumented lumbar curves improved by 33.9% at the last follow-up. The radiological changes from 6 weeks to the last follow-up were statistically not significant. The clinical rib hump improved by 54% at the last follow-up. There were no significant changes in the pulmonary function. FVC% was 81.04% preoperatively, 76.41% at 6 months and 80.38% at the 2-year follow-up. The results of SRS 24 questionnaire improved from a total of 61.40 points preoperatively to 100.50 points at 6 months and 98.62 points at the 2-year follow-up. There were no neurological or thoracotomy related complications, no pseudarthrosis, no implant pullout or breakage.

CONCLUSION

A good deformity correction without loss of correction or adding on, a good cosmetic result and good patient's satisfaction were achieved through shorter than end-to-end thoracic fusions. The radiological residual deformity is acceptable. Anterior correction of thoracic scoliosis with a short spinal fusion is recommended to keep the large part of the spine mobile. A very short fusion, small thoracotomy incision, low-profile implants and complete closure of parietal pleura are keys to prevent reduction in postoperative lung function.

Does thoracoscopic anterior release of rigid idiopathic scolioses associated with correction by posterior instrumentation result in better long-term frontal and sagittal balance?

INTRODUCTION

The aim of treatment of scolioses is to reduce deformities and restore balance in the spine.

HYPOTHESES

In rigid forms of scoliosis, associating anterior release could provide greater frontal and/or sagittal plane correction and improve balance in the spine.

PATIENTS AND METHODS

This study compared correction and long-term balance on two planes between two homogeneous groups of idiopathic rigid scolioses treated with and without thoracoscopic release. The study included rigid scolioses with less than 35% reducibility and a Cobb angle of more than 60°, who all underwent posterior correction using a rod rotation technique. There were 29 patients, 14 who underwent a one-step procedure (group A) and 15 a two-step procedure (group B), with the subgroups of kyphoscolioses and lordoscolioses determined in each group. Frontal balance, Cobb angle, thoracic kyphosis and the Jackson plumbline were measured on pre- and postoperative X-rays and at the final follow-up.

RESULTS

The mean long-term final follow-up was 144 months for group A and 54 months for group B. Frontal plane correction was identical in groups A and B. Frontal balance was preserved in all cases at the final follow-up. Sagittal balance was not modified with or without anterior release. The thoracoscopic release step resulted in an additional correction of 15.5° (23%) of thoracic hyperkyphosis in patients with kyphoscoliosis (P=0.003).

DISCUSSION

Thoracoscopy did not improve short term results in the Cobb angle or frontal or saggital balance. Nevertheless, enhanced correction of thoracic hyperkyphosis was obtained with this procedure. In this study, the association of thoracoscopic anterior release with posterior correction by rod rotation to treat rigid scolioses did not appear to improve results, except for the correction of thoracic hyperkyphosis.

Pulmonary function in adolescent idiopathic scoliosis relative to the surgical procedure: a 10-year follow-up analysis

STUDY DESIGN

Retrospective review.

OBJECTIVE

To assess long-term pulmonary function after surgical correction of adolescent idiopathic scoliosis.

SUMMARY OF BACKGROUND DATA

Pulmonary function is known to decline with increasing age. Although there are published reports on 2- and 5-year pulmonary function test outcomesafter various surgical approaches for adolescent idiopathic scoliosis, 10-year pulmonary function tests of these patients is unknown.

METHODS

Forty-nine patients were divided into two groups who underwent surgery for adolescent idiopathic scoliosis at a single institution. There were 46 female patients and three male patients. All group one patients (n = 38) had some form of chest wall disruption during their spinal fusion: group 1A (n = 17) underwent open anterior spinal fusion/instrumentation, group 1B (n = 9) had a combined open anteroposterior spinal fusion, and group 1C (n = 12) had a posterior spinal fusion/instrumentation with thoracoplasty. Group 2 patients (n = 11) underwent posterior spinal fusion/instrumentation with iliac crest bone graft and no chest cage disruption. We evaluated preoperative and 10-year pulmonary function test values.

RESULTS

Within-group comparison revealed that group 1 experienced no change in forced vital capacity (FVC) and forced expiratory volume in 1 second (FEV(1)), but demonstrated a significant decrease in percent-predicted FVC (85% vs. 79%, P = 0.00086) and FEV(1) values (80% vs. 76%, P = 0.038). Conversely, group 2 experienced a significant increase in both FVC (3.25L vs. 3.66L, P = 0.011) and FEV(1) (2.77L vs. 3.10L, P = 0.0019), but no changes in percent-predicted values from baseline to 10 years. No changes were noted in percent-predicted values between 5 and 10 years in either group.

CONCLUSION

Intraoperative chest wall violation produced detrimental pulmonary effects, as reflected by reduced percent-predicted values at 10-year follow-up. Posterior-only procedures, which spared the chest wall, showed significant improvements in FVC and FEV(1) absolute values without any change in percent-predicted values.

Maximal pulmonary recovery after spinal fusion for adolescent idiopathic scoliosis: how do anterior approaches compare?

STUDY DESIGN

Retrospective analysis of prospectively collected data.

OBJECTIVE

To compare the relative rates of pulmonary recovery and maximal pulmonary function with surgical approach.

SUMMARY OF BACKGROUND DATA

Anterior versus posterior spinal fusion (ASF, PSF) for the treatment of adolescent idiopathic scoliosis (AIS) has been debated. Although procedures that violate the chest wall may compromise pulmonary function, lung function continues to improve after surgery at variable rates depending upon surgical approach.

METHODS

We reviewed the medical records from one hundred fifty nine AIS patients (age 15.6±2.2; 113 women; 46 men) treated with spinal fusion from 2003 to 2007 by a single surgeon. Forced expiratory volume in one second (FEV1), forced vital capacity (FVC), and radiographic measurements were evaluated before surgery and at 1, 3, 6, 12, and 24-months follow-up on average. Four surgical groups were compared: PSF, ASF (open thoracoabdominal approach for thoracolumbar curvature), video-assisted thoracoscopic surgical release with instrumentation (VATS-I), and VATS with PSF. FEV1 and FVC were fitted to model to evaluate the immediate postoperative pulmonary function (Yo), maximal recovery (Plateau), and rate (K) of pulmonary improvement.

RESULTS

Patients in each surgical subgroup were as follows: PSF (Lenke 1: n=50, Lenke 2,3: n=20), ASF (Lenke 5, n=35), VATS-I (Lenke 1=31, Lenke 3=1), and VATS+PSF (Lenke1: n=9, Lenke 2-6: n=13). Early postoperative pulmonary function was higher with ASF and PSF as compared to both VATS groups (P<0.05). Comparing all curve types, VATS-I showed a small decline of absolute FEV1 compared to PSF at 2-years follow-up. Comparing thoracic curves, however, no differences in FEV1 or FVC were noted at 6 to 12 months until 2-years follow-up. The rate of recovery (K) was equivalent for all surgical approaches and curve types.

CONCLUSION

Compared to ASF or PSF, VATS procedures showed an initial decline in pulmonary function, which resolved fully by 6- to 12-months follow-up. Modest declines in maximal pulmonary function with VATS-I were seen when comparing all curve types together but not when comparing Lenke 1 curves alone. VATS procedures for thoracic scoliosis and open approaches for thoracolumbar curve types were associated with minimal to no permanent deficits.

The rate of screw misplacement in segmental pedicle screw fixation in adolescent idiopathic scoliosis

BACKGROUND AND PURPOSE

There are no reports in the literature on the influence of learning on the pedicle screw insertion. We studied the effect of learning on the rate of screw misplacement in patients with adolescent idiopathic scoliosis treated with segmental pedicle screw fixation.

METHOD

We retrospectively evaluated low-dose spine computed tomography of 116 consecutive patients (aged 16 (12-24) years, 94 females) who were operated during 4 periods over 2005-2009 (group 1: patients operated autumn 2005-2006; group 2: 2007; group 3: 2008; and group 4: 2009). 5 types of misplacement were recorded: medial cortical perforation, lateral cortical perforation, anterior cortical perforation of the vertebral body, endplate perforation, and perforation of the neural foramen.

RESULTS

2,201 pedicle screws were evaluated, with an average of 19 screws per patient. The rate of screw misplacement for the whole study was 14%. The rate of lateral and medial cortical perforation was 7% and 5%. There was an inverse correlation between the occurrence of misplacement and the patient number, i.e. the date of operation (r = -0.35; p < 0.001). The skillfulness of screw insertion improved with reduction of the rate of screw misplacement from 20% in 2005-2006 to 11% in 2009, with a breakpoint at the end of the first study period (34 patients).

INTERPRETATION

We found a substantial learning curve; cumulative experience may have contributed to continued reduction of misplacement rate.

The relationship between deformity correction and clinical outcomes after thoracoscopic scoliosis surgery: a prospective series of one hundred patients

STUDY DESIGN

Prospective clinical case series of 100 patients receiving thoracoscopic anterior scoliosis correction.

OBJECTIVE

To evaluate the relationship between clinical outcomes of thoracoscopic anterior scoliosis surgery and deformity correction, using the Scoliosis Research Society (SRS) outcomes instrument.

SUMMARY OF BACKGROUND DATA

Surgical treatment of scoliosis is quantitatively assessed in the clinic, using radiographic measures of deformity correction and the rib hump, but it is important to understand the extent to which these quantitative measures correlate with self-reported improvements in patients' quality of life after surgery.

METHODS

A series of 100 consecutive adolescent idiopathic scoliosis patients received a single anterior rod via a thoracoscopic approach at the Mater Children's Hospital, Brisbane, Australia. Patients completed SRS outcomes questionnaires before surgery and at 24 months after surgery. Multiple regression and t tests were used to investigate the relationship between SRS scores and deformity correction achieved (radiographic measurements and rib hump) after surgery.

RESULTS

There were 94 females and 6 males with a mean age of 16.1 years. The mean Cobb angle improved from 52° before surgery to 25° after surgery (52%) and the mean rib hump improved from 16° to 8° (51%). The mean total SRS score for the cohort was 99.4/120. None of the deformity-related parameters in the multiple-regression were significant. However, patients with the lowest postoperative major Cobb angles reported significantly higher SRS scores than those with the highest postoperative Cobb angles, but there was no difference on the basis of rib hump correction. There were no significant differences between patients with either rod fractures or screw-related complications compared to those without complications.

CONCLUSION

Patients undergoing thoracoscopic anterior scoliosis correction reported good SRS scores which are comparable with those in previous studies. Postoperative major Cobb angle is a significant predictor of patient satisfaction when comparing subgroups of patients with the highest and lowest postoperative Cobb angles.

The morbidity of open transthoracic approach for anterior scoliosis correction

STUDY DESIGN

Retrospective study.

OBJECTIVE

To analyze the patient satisfaction and the patients' perceived approach-related morbidity (ArM) after open thoracotomy (OTC) for instrumented anterior scoliosis surgery.

SUMMARY OF BACKGROUND DATA

There is no mid- to long-term data on the patients' perceived ArM concerning chest wall dissection for open anterior scoliosis correction.

METHODS

A specific questionnaire was used to retrospectively evaluate mid- to long-term follow-up data concerning ArM after OTC of patients younger than 30 years (range, 11-28 years) who underwent anterior open transthoracic scoliosis surgery. The questionnaire was comprised of detailed scar-related questions. Applying strict inclusion criteria, we could analyze outcomes in terms of percentage morbidity (morbidity [%]) of 40 patients who underwent OTC for instrumented scoliosis correction.

RESULTS

Mean age of the patients was 16 ± 3.8 years, follow-up was 61.5 ± 72.6 months on average, and mean incision length was 25.7 ± 3.1 cm. Mean number of levels fused was 5.9 ± 1.5. Single thoracotomy was performed in 25 patients and a thoracoabdominal approach in 15 patients. Mean morbidity (0%, not delineating no ArM; 100%, delineating highest ArM) was 5.4% ± 11.3%; 47.5% of patients had no morbidity; 12.5% had morbidity >10% (mean: 28.5%). Signs of intercostal neuralgia (ICN) were present in 10%. Patients judged their clinical outcome as "good" in 20% and "excellent" in 80%. Statistical analysis did not reveal differences in outcomes and percentage morbidity concerning age of patients, extent of approach (thoracotomy vs. thoracoabdominal approach) and incision length, gender, or follow-up length. However, the presence of ICN had a significant effect on the outcome, showing high correlation with increased morbidity (P < 0.0001). In the clinical judgment of outcomes, the severity of the ArM after OTC was mild, except for 2 patients who had moderate approach and scar-related morbidity.

CONCLUSION

ArM after open thoracic spinal surgery or thoracoscopic procedures can be assessed using the questionnaire. The current study showed that ArM in young patients who underwent OTC for anterior instrumented scoliosis correction was low. Patients with increased signs of ICN did worse in terms of the questionnaire survey. The study showed that neither cosmesis nor scar-related problems were a concern for patients undergoing OTC.

Video-assisted thoracoscopic surgery for correction of adolescent idiopatic scoliosis: comparison of 4.5 mm versus 5.5 mm rod constructs

PURPOSE

The purpose of this study is to report the comparative results of thoracoscopic correction achieved via cantilever technique using a 4.5 mm thin rod and the poly-axial reduction screw technique using a 5.5 mm thick rod in Lenke type 1 adolescent idiopathic scoliosis (AIS).

MATERIALS AND METHODS

Radiographic data, Scoliosis Research Society (SRS) patient-based outcome questionnaires, and operative records were reviewed for forty-nine patients undergoing surgical treatment of scoliosis. The study group was divided into a 4.5 mm thin rod group (n = 24) and a 5.5 mm thick rod group (n = 25). The radiographic parameters that were analyzed included coronal curve correction, the most caudal instrumented vertebra tilt angle correction, coronal balance, and thoracic kyphosis.

RESULTS

The major curve was corrected from 49.8 degrees and 47.2 degrees pre-operatively to 24.5 degrees and 18.8 degrees at the final follow-up for the thin and thick rod groups, respectively (50.8% vs. 60.2% correction). There were no significant differences between the two groups in terms of kyphosis, coronal balance, or tilt angle at the time of the final follow-up. The mean number of levels fused was 6.2 in the thin rod group, compared with 5.9 levels in the thick rod group. There were no major intraoperative complications in either group.

CONCLUSION

Significant correction loss was observed in the thin rod system at the final follow-up though both groups had comparable correction immediately post-operative. Therefore, the thick rod with poly axial screw system helps to maintain post-operative correction.

Approach-related morbidity in transthoracic anterior spine surgery: a clinical study and review of literature

BACKGROUND: Anterior access to the thoracic spine is done by open thoracotomy (OTC) or video-assisted thoracoscopic surgery (VATS). VATS is known as the method which results in lower morbidity rates, but there is little evidence of its less invasiveness. Objective: The current study yielded for outcome data concerning patients' perception of approach-related morbidity (ArM) following OTC for spinal surgery and that of a control group having a chest tube thoracotomy (CTT). METHODS: We performed a questionnaire assessment of ArM after OTC and CTT. Applying strict inclusion criteria, we compared outcomes in terms of percentage morbidity (Morbidity %) of 43 patients that underwent OTC for instrumented scoliosis correction to 30 patients that had CTT for minor thoracic pathologies (e.g., pneumothorax). RESULTS: Mean age in CTT and OTC Group was 50.2 and 16.5 years old, follow-up was of 32.2 and 58.4 months, and mean incision length was 2.5 and 25.5 cm, respectively. Mean number of levels fused in the OTC Group was 5.8. Mean morbidity (0% delineating no cases, 100% delineating highest morbidity) for the CTT Group was 10.8±15.4% (0-59.5%), 42% of patients had no morbidity. Signs of intercostal neuralgia (ICN) were present in 16.7%. A total of 35.5% had a morbidity >10% (mean: 27.5%), and 10% of morbidity cases were defined as having a chronic post-thoracotomy pain (CPP). In the OTC Group, mean morbidity was 7.0±12.7% (0-52.1%), 44% had no morbidity. Out of the sample, 18.6% had morbidity >10% (mean: 28.6%). Signs of ICN were present in 14%. In both groups, the presence of ICN had a significant impact on and showed correlation with morbidity (p<0.0001). In terms of clinical judgement, the severity of the ArM after a CTT or OTC was generally mild except for one patient in each group. Age and follow-up were significantly different between groups (p<0.0001, p=0.02), but the intergroup difference in morbidity was not significant (p=0.08). CONCLUSIONS: ArM after open thoracic spinal surgery or VATS procedures can be assessed using the questionnaire. To put ArM of OTC into perspective, a Control Group with simple CTT was selected, demonstrating that morbidity was not different between the OTC and CTT groups. Patients with increased signs of ICN do worse which was reflected by increased morbidity in both groups. The study demonstrates that not only the cosmesis is not a concern for patients undergoing OTC, but neither is the ArM a concern, equalling that of a simple CTT.

Health-related quality of life in untreated versus brace-treated patients with adolescent idiopathic scoliosis: a long-term follow-up

STUDY DESIGN

The previous Scoliosis Research Society brace study (JBJS-A, 1995) included patients with adolescent idiopathic scoliosis (AIS) with moderate curve sizes (25 degrees -35 degrees). The Swedish patients in this study were examined in a long-term follow-up.

OBJECTIVE

The aim was to analyze and compare quality of life in adulthood between AIS patients who were only observed or treated with a brace during adolescence.

SUMMARY OF BACKGROUND DATA

Quality of life as measured by the SRS-22 has not previously been presented for adult untreated AIS patients.

METHODS

Forty patients who were only observed (due to a curve increase of less than 6 degrees until maturity), and 37 brace-treated patients attended the complete follow-up, including clinical and radiologic examination, and answered 2 quality of life questionnaires (SRS-22 and Short Form-36 [SF-36]).

RESULTS

No differences were found between the groups in terms of age at follow-up (mean: 32 years), follow-up time after maturity (mean: 16.0 years), and curve size at inclusion (mean: 30 degrees) or at follow-up (mean: 35 degrees). The SRS-22/total score was a mean of 4.2 for braced patients and 4.1 for only observed patients. Neither total scores/subscales of the SRS-22 or SF-36 differed significantly between the groups. For the SF-36, no differences in relation to the Swedish age-matched norm scales were found for either group.

CONCLUSION

Patients with moderate AIS report good quality of life in their 30s, as measured by both the SRS-22 and SF-36, regardless of whether they received no active treatment or were brace treated during adolescence. Neither of the groups displayed any difference compared with the age-matched norm groups for the SF-36.

Adolescent idiopathic scoliosis treated with open instrumented anterior spinal fusion: five-year follow-up

STUDY DESIGN

A multicenter prospective database was queried for patients who underwent open instrumented anterior spinal fusion (OASF) for treatment of primary thoracic (Lenke 1) adolescent idiopathic scoliosis (AIS).

OBJECTIVES

To present the intermediate radiographic and pulmonary function testing (PFT) data from patients who underwent OASF using modern, rigid instrumentation.

SUMMARY OF BACKGROUND DATA

Anterior spinal fusion is an excellent method to correct the 3-dimensional deformity produced by AIS. Modern instrumentation consisting of stronger metals, unthreaded rods, and dual rod systems should theoretically decrease the incidence of rod breakage, pseudarthrosis, and loss of correction seen in earlier OASF studies. The paucity of intermediate and long-term data prevents surgeons and patients from making an informed decision regarding the true incidence of these complications.

METHODS

Of 101 potential patients who underwent OASF with a minimum 5-year follow-up, 85 (85%) were studied. Standing radiographs were analyzed before surgery and at first standing erect, 2-year, and 5-year follow-up. PFT data were collected before surgery and at 5 years after surgery.

RESULTS

Complete 5-year follow-up was obtained in 85 patients. Five years after surgery, the mean coronal correction was 26 degrees (51%; P < 0.05) and the thoracolumbar/lumbar curve improved 16 degrees (51%). There was a 9-degree (P < 0.001) increase in kyphosis, and there were 9 patients (11%) in whom the C7 plumb line translated >2 cm. There was a 6.7% decrease in predicted FEV1 over the 5-year period, from 75.5% +/- 13% before surgery to 68.8% +/- 2% at 5-year follow-up (P = 0.007); however, there was no significant change in FVC. There were 3 significant adverse events: 1 implant breakage requiring reoperation and 2 cases of progression of the main thoracic curve requiring reoperation.

CONCLUSION

OASF is a reproducible and safe method to treat thoracic AIS. It provides good coronal and sagittal correction of the main thoracic and compensatory thoracolumbar/lumbar curves that is maintained with intermediate term follow-up. In skeletally immature children, this technique can cause an increase in kyphosis beyond normal values, and less correction of kyphosis should be considered during instrumentation. As with any procedure that employs a thoracotomy, pulmonary function is mildly decreased at final follow-up.

Thoracic pedicle screw instrumentation: the learning curve and evolution in technique in the treatment of adolescent idiopathic scoliosis

STUDY DESIGN

Retrospective review.

OBJECTIVE

The purpose of this study is to evaluate the learning curve and associated evolution in surgical technique with thoracic pedicle screw instrumentation in adolescent idiopathic scoliosis (AIS).

SUMMARY OF BACKGROUND DATA

Common treatment for AIS now includes posterior spinal fusion, using thoracic pedicle screws (TPS). It is critical to assess the efficacy, safety profile, and learning curve associated with this technique as its use becomes more widespread among inexperienced surgeons.

METHODS

Retrospective review of the senior author's first 96 TPS cases for Lenke Type I AIS curves. Multiple regression techniques were used to discern whether increasing case number (CN) was associated with improved perioperative and 2-year minimum radiographic and clinical outcomes. The 96 cases were divided into 4 equal quartiles of 24 cases/group (i.e., Q1-Q4) and compared using analysis of variance measures.

RESULTS

A total of 1169 thoracic pedicle screws were placed in 96 patients. We found a significant correlation between CN and major curve correction at 2 years (P < 0.0001), inverse correlation between CN and length of stay (P = 0.02), and estimated blood loss (P = 0.03), but no differences in cell saver or complications. Univariate analysis revealed significant inverse correlations between increasing CN and transfusion rate (P = 0.02) and operative times (P = 0.0001). Total number of screws placed (Q1:9.4 vs. Q4:16.2, P < 0.0001) and number of screws/level (Q1:0.98 vs. Q4:1.64, P < 0.0001) increased linearly with increasing CN, whereas the average time for screw placement (Q1:24.2 vs. Q4:11.4 minutes, P < 0.0001) and ability to maintain T2-T12 kyphosis decreased (Q1:0.21 vs. Q4:-5.5 P = 0.02) with increasing CN.

CONCLUSION

There is a significant learning curve associated with thoracic pedicle screw placement in AIS. We describe several technical steps that can be taken to increase the safety of screw placement at the beginning of the learning curve. Inexperienced surgeons should expect a gradual improvement over time in radiographic and clinical outcomes.

Quality of life in patients treated surgically for scoliosis: longer than sixteen-year follow-up

STUDY DESIGN

A retrospective study.

OBJECTIVE

To evaluate the long-term quality of life (QOL) of patients treated surgically for scoliosis.

SUMMARY OF BACKGROUND DATA

Measures of long-term outcome after surgery for scoliosis have focused mainly on radiologic changes. However, QOL issues such as working status and marital status are the subjects of greatest concern for patients who will undergo surgical treatment for scoliosis.

METHODS

Thirty-two patients treated surgically for scoliosis between 1976 and 1989 were included in this study. The mean duration of follow-up was 21.1 years. Eighteen patients had adolescent idiopathic scoliosis, 8 congenital scoliosis, and 6 symptomatic scoliosis. We evaluated long-term outcome by direct interview with patients. Working status, marital status, and childbearing were determined in addition to clinical and radiologic evaluation. Patients were also asked to fill out the short form (SF)-36 and Scoliosis Research Society (SRS)-22 questionnaires.

RESULTS

Twenty-seven patients (84.4%) were or had been engaged in various occupations without marked difficulty. Although none of the male patients was married, 62.5% of the female patients were married. Half of the female patients had delivered babies after surgery, and the mean number of such children was 1.83. On the SF-36, none of the scores for subjects with idiopathic or congenital scoliosis were markedly different from those for age-matched healthy controls. Multivariate logistic regression analysis revealed that marked preoperative Cobb angle and positive sagittal balance at the most recent follow-up were significantly associated with increased odds ratio for poor scores on the SRS-22.

CONCLUSION

We evaluated long-term QOL in patients treated surgically for scoliosis, and found that it was not impaired, particularly in the case of patients with idiopathic or congenital scoliosis. Larger preoperative Cobb angle and positive sagittal balance at the most recent follow-up were related to poor outcome in QOL as assessed by the SRS-22.

Thoracoscopic anterior instrumented fusion for adolescent idiopathic scoliosis with emphasis on the sagittal plane

BACKGROUND CONTEXT

Anterior fusion through an open thoracotomy restores kyphosis more reliably than posterior techniques in patients with thoracic adolescent idiopathic scoliosis (AIS). Video-assisted thoracoscopic spinal fusion and instrumentation (VATS) minimizes the morbidity, from soft tissue and muscle dissection that accompanies traditional open thoracotomy. To our knowledge, there has not been a comprehensive analysis of VATS with respect to radiographic and clinical outcomes in the sagittal plane.

PURPOSE

To measure the radiographic and clinical outcomes after VATS with emphasis on the sagittal plane.

STUDY DESIGN/SETTING

A retrospective, radiographic review of 26 consecutive patients with Lenke type-I AIS who underwent VATS.

METHODS

Radiographs of 26 consecutive patients with Lenke type-I AIS curves operated by a single surgeon were retrospectively reviewed after VATS. Sagittal and coronal parameters were compared with reported data for open anterior and posterior procedures.

RESULTS

There was an increase in kyphosis from baseline to final follow-up by 6.6 degrees (25%) from T2 to T12 (p<.0001), 8.7 degrees (50%) from T5 to T12 (p<.0001), and 8 degrees (54%) in the instrumented segment (p<.0001). Junctional kyphosis did not occur. No differences were detected in sagittal measurements between the first postoperative erect and the final radiographs. Patients experienced significant improvements from baseline to 2 years in Scoliosis Research Society-22 Health-Related Quality-of-Life Outcome Questionnaire scores (p<.0001).

CONCLUSIONS

Video-assisted thoracoscopic spinal fusion and instrumentation, in agreement with results reported for open anterior instrumentation, reliably restores or increases thoracic kyphosis while preserving junctional alignment in thoracic AIS.

Radiographic outcomes over time after endoscopic anterior scoliosis correction: a prospective series of 106 patients

STUDY DESIGN

A prospective, consecutive series of 106 patients receiving endoscopic anterior scoliosis correction.

OBJECTIVE

To analyze changes in radiographic parameters and rib hump in the 2 years after surgery.

SUMMARY OF BACKGROUND DATA

Endoscopic anterior scoliosis correction is a level sparing approach and therefore, it is important to assess the amount of decompensation which occurs after surgery.

METHODS

All patients received a single anterior rod and vertebral body screws using a standard compression technique. Cleared disc spaces were packed with either mulched femoral head allograft or rib head/iliac crest autograft. Radiographic parameters (major, instrumented, minor Cobb, T5-T12 kyphosis) and rib hump were measured at 2, 6, 12, and 24 months after surgery. Paired t tests and Wilcoxon signed ranks tests were used to assess the statistical significant of changes between adjacent time intervals.

RESULTS

Mean loss of major curve correction from 2 to 24 months after surgery was 4 degrees. Mean loss of rib hump correction was 1.4 degrees. Mean sagittal kyphosis increased from 27 degrees at 2 months to 30.6 degrees at 24 months. Rod fractures and screw-related complications resulted in several degrees less correction than patients without complications, but overall there was no clinically significant decompensation after complications.

CONCLUSION

There are small changes in deformity measures after endoscopic anterior scoliosis surgery, which are statistically significant but not clinically significant.

Treatment of thoracic scoliosis: are monoaxial thoracic pedicle screws the best form of fixation for correction?

STUDY DESIGN

Multicenter retrospective cohort study of 100 consecutive patients.

OBJECTIVE

Compare the coronal and sagittal plane radiographic outcomes and clinical rib hump deformity correction in patients who underwent posterior spinal fusion for adolescent idiopathic scoliosis using hybrid instrumentation, polyaxial (POLY) segmental pedicle screw fixation, or monoaxial (MONO) segmental pedicle screw fixation.

SUMMARY OF BACKGROUND DATA

Instrumentation for the treatment of scoliosis has evolved. Current techniques include use of a combination of hooks, sublaminar wires, and pedicle screws (HYBRID), as well as segmental pedicle screw fixation with either monoaxial or polyaxial screw anchors.

METHODS

Data were obtained from a multicenter prospective database registry. Radiographic assessment was performed from radiographs taken before surgery and 2 years after surgery. Intraoperative parameters assessed included operative time, estimated blood loss, and whether or not a thoracoplasty was performed. Clinical evaluation of the angle of trunk rotation was done with an inclinometer.

RESULTS

Preoperative thoracic curvature and curve flexibility, age, Lenke curve type, and number of levels fused was similar for each group. Significantly more anchors per level were used in the MONO group (1.69) and in the HYBRID group (1.24) compared to the POLY group (1.06). There were no statistical differences among the groups with respect to major thoracic curve correction (MONO: 69%; POLY: 68%; HYBRID: 62%, P = 0.22). POLY constructs maintained thoracic kyphosis, whereas MONO and HYBRID had a tendency toward loss of thoracic kyphosis and there was a trend toward a greater percent thoracic angle of trunk rotation correction in the MONO group (55%) compared with the POLY group (32%, P = 0.10), but no differences compared with Hybrid (55%, P > 0.05).

CONCLUSION

Similar coronal and sagittal plane correction was achieved in thoracic adolescent idiopathic scoliosis with 3 different constructs. There was a trend toward improved correction of clinical rib hump deformity with MONO screw constructs compared with POLY screw constructs.

Novel dual-rod screw for thoracoscopic anterior instrumentation: biomechanical evaluation compared with single-rod and double-screw/double-rod anterior constructs

STUDY DESIGN

A novel dual-rod screw was designed to provide a second-rod augmentation at the critical apical/middle segments of the single-rod thoracoscopic anterior construct. Biomechanical testing was performed on pig thoracic spines instrumented with 7-segment anterior scoliosis constructs.

OBJECTIVES

To analyze the biomechanical performance of the new implant, and compare it to a single-rod and double-rod anterior constructs.

SUMMARY OF BACKGROUND DATA

Using single-rod thoracoscopic anterior instrumentation for thoracic scoliosis, the complications of rod breakage at apex, high rate of nonunion, and resultant loss of coronal and sagittal correction has been reported. Inadequate construct stiffness because of a smaller diameter single rod has been implicated as the cause of these complications.

METHODS

Twelve pig thoracic spines were instrumented over 7 segments with: (1) single-rod construct, (2) short second-rod augmentation at the apex of the single-rod construct, (3) long second-rod augmentation at middle segments of the single-rod construct, and (4) double-screw/double-rod anterior construct. The spines were tested in flexion-extension, left-right lateral bending, and torsion, using pure bending moments. Strain gauges attached to the primary single rod at the cephalad, middle, and caudal portions were used and the maximum tensile stress was recorded.

RESULTS

In the single-rod construct, the middle portion stress was 39% to 51% greater than the stress in the cephalad and caudal portions in flexion-extension (P < 0.05), and the cephalad portion stress was 39% to 65% greater than the stress in the middle and caudal portions in right lateral bending and torsion (P < 0.05). When a second rod was added at the apical/middle portion, the middle portion stress decreased from 50% to 72% in flexion-extension and right lateral bending (P < 0.05). In addition, the second rod decreased the primary single-rod stress at the cephalad portion by 48% (left torsion) and the caudal portion by 50% (flexion). Double-screw/double-rod construct significantly increases the construct stiffness in comparison with the single-rod construct. However, it did not add any construct stiffness at the critical apical segments when compared to the constructs in which the second rod augmented the single-rod constructs.

CONCLUSION

A novel dual-rod screw was designed to combine the standard single-rod construct with the addition of a second rod at the critical apical/middle segments and increase construct stiffness and stability. This implant may therefore prevent pseudarthrosis and rod breakage by enhancing construct stiffness.

Video-assisted thoracoscopic spinal fusion compared with posterior spinal fusion with thoracic pedicle screws for thoracic adolescent idiopathic scoliosis

BACKGROUND

Although the gold standard for the surgical treatment of thoracic adolescent idiopathic scoliosis has been posterior spinal fusion, video-assisted thoracoscopic surgery recently has become a viable alternative. In the treatment of structural thoracic curves, video-assisted thoracoscopic surgery has demonstrated outcomes equivalent to those of posterior spinal fusion with use of an all-hook or hybrid pedicle screw-hook construct. No study to date, however, has compared this technique with posterior spinal fusion with thoracic pedicle screws, which has become the current standard of care.

METHODS

A matched-pair analysis of thirty-four consecutive patients (seventeen pairs) undergoing either video-assisted thoracoscopic surgery or posterior spinal fusion with thoracic pedicle screws for the treatment of structural scoliosis was performed; the study included eight male and twenty-six female patients with an average age of 15.0 years. Pairs were matched according to curve type and magnitude, patient age, and sex. Clinical data, the results of the Scoliosis Research Society questionnaire, and radiographic data were collected preoperatively and at a minimum of two years postoperatively and were compared between the groups.

RESULTS

Video-assisted thoracoscopic surgery was associated with significantly increased operative times (mean, 326 compared with 246 minutes; p = 0.033) and reduced blood loss (mean, 371 compared with 1018 mL; p = 0.001), but there were no differences between the groups in terms of the transfusion rate (18% compared with 29%; p = 0.69) or the length of stay. The percentage correction of the major curve was 57.3% for the video-assisted thoracoscopic surgery group and 63.8% for the posterior spinal fusion group (p = 0.08). With the numbers available, no differences were detected in terms of the cephalad thoracic curve, caudad compensatory lumbar curve, coronal balance, thoracic kyphosis, lumbar lordosis, sagittal balance, end vertebra tilt angle, or angle of trunk rotation measurements preoperatively or at the time of the latest follow-up. The average number of fused levels was 5.9 in the video-assisted thoracoscopic surgery group and 8.9 in the posterior spinal fusion group (p < 0.001). Relative to the Cobb end vertebra, the most caudad instrumented vertebra was 0.81 level more cephalad in the video-assisted thoracoscopic surgery group as compared with the posterior spinal fusion group (p = 0.004). No significant differences were detected in any of the questionnaire outcomes at any time point. Although both groups experienced similar improvement from baseline in terms of pulmonary function at two years, the posterior spinal fusion group had significantly improved peak flow measurements (p = 0.04) in comparison with the video-assisted thoracoscopic surgery group.

CONCLUSIONS

For single thoracic curves of <70 degrees in patients with a normal or hypokyphotic thoracic spine, video-assisted thoracoscopic surgery can produce equivalent radiographic results, patient-based clinical outcomes, and complication rates in comparison with posterior spinal fusion with thoracic pedicle screws, with the exception that posterior spinal fusion with thoracic pedicle screws may result in better major curve correction. The potential advantages of video-assisted thoracoscopic surgery over posterior spinal fusion with thoracic pedicle screws include reduced blood loss, fewer total levels fused, and the preservation of nearly one caudad fusion level, whereas the disadvantages include increased operative times and slightly less improvement in pulmonary function.

Video-assisted anterior thoracoscopic spinal fusion versus posterior spinal fusion: a comparative study utilizing the SRS-22 outcome instrument

STUDY DESIGN

Retrospective, matched cohort.

OBJECTIVE

The purpose of this study was to compare the Scoliosis Research Society's Outcomes measures (SRS-22) scores, as well as radiographic outcomes of patients with adolescent idiopathic scoliosis who had a single thoracic structural curvature treated by either posterior spinal fusion (PSF) or video-assisted thoracoscopic (VATS) fusion.

SUMMARY OF BACKGROUND DATA

To our knowledge, there has been no prior matched-pair study comparing outcomes between 2 different surgical approaches for the same curve type using the SRS-22 outcomes instrument.

METHODS

Patients were evaluated before surgery and at 2-year follow-up. A total of 52 patients with Lenke type I curvature were paired by age, gender, and major Cobb angle into 2 groups: PSF (8 men, 18 women, mean age 14.7, mean Cobb angle 48.7) and VATS (mean age 14.8, mean Cobb angle 49.1). All questionnaire scores were classified based on domains of activity, pain, self-image, mental health, satisfaction, and total scores.

RESULTS

The patients in the VATS group scored higher than the PSF group in the domains of self-image (P < 0.02), mental health (P < 0.03), and total score (P < 0.05), but not activity, pain, or satisfaction at 2 years. There was no difference in percent curve correction between the match-paired groups. Within-group analyses revealed that VATS patients experienced insignificant improvements compared with PSF in most SRS-22 domains and a trend toward significant overall mean score improvement (P = 0.06).

CONCLUSION

Based on the SRS-22 questionnaire data, the VATS patients scored higher in the self-image, mental health, and total domains despite similar curve corrections. We hypothesize that this may be related to the smaller surgical scar and less invasive nature of VATS.

Surgical treatment of main thoracic scoliosis with thoracoscopic anterior instrumentation. a five-year follow-up study

BACKGROUND

The surgical outcomes in patients with scoliosis at two years following anterior thoracoscopic spinal instrumentation and fusion have been reported. The purpose of this study was to evaluate the results at five years.

METHODS

A consecutive series of forty-one patients with major thoracic scoliosis treated with anterior thoracoscopic spinal instrumentation was evaluated at regular intervals. Prospectively collected data included patient demographics, radiographic measurements, clinical deformity measures, pulmonary function, an assessment of intervertebral fusion, and the scores on the Scoliosis Research Society (SRS-24) outcomes instrument. Perioperative and postoperative complications were recorded. Patient data for the preoperative, two-year, and five-year postoperative time points were compared. In addition, a univariate analysis compared selected two-year radiographic, pulmonary function, and SRS-24 data of the study cohort and those of the patients lost to follow-up.

RESULTS

Twenty-five (61%) of the original forty-one patients had five-year follow-up data and were included in the analysis. Between the two-year and five-year follow-up visits, no significant changes were observed with regard to the average percent correction of the major Cobb angle (56% +/- 11% and 52% +/- 14%, respectively), average total lung capacity as a percent of the predicted value (95% +/- 14% and 91% +/- 10%), and the average total SRS-24 score (4.2 +/- 0.4 and 4.1 +/- 0.7). Radiographic evaluation of intervertebral fusion at five years revealed convincing evidence of a fusion with remodeling and trabeculae present at 151 (97%) of the 155 instrumented motion segments. No postoperative infections or clinically relevant neurovascular complications were observed. Rod failure occurred in three patients, and three patients required a surgical revision with posterior spinal instrumentation and fusion.

CONCLUSIONS

Thoracoscopic anterior instrumentation for main thoracic idiopathic scoliosis results in five-year outcomes comparable with those reported previously for open anterior and posterior techniques. The radiographic findings, pulmonary function, and clinical measures remain stable between the two and five-year follow-up time points. Thoracoscopic instrumentation provides a viable alternative to treat spinal deformity; however, the risks of pseudarthrosis, hardware failure, and surgical revision should be considered along with the advantages of limited muscular dissection and improved scar appearance.

LEVEL OF EVIDENCE

Therapeutic Level IV. See Instructions to Authors for a complete description of levels of evidence.

Adolescent idiopathic scoliosis (AIS) - an indication for surgery? A systematic review of the literature

PURPOSE

Historically, the treatment options for AIS, the most common form of scoliosis are: Exercises, in-patient rehabilitation, braces and surgery. While there is evidence in the form of prospective controlled studies that Scoliosis Intensive Rehabilitation (SIR) and braces can alter the natural history of the condition, there is no review on prospective controlled trials for surgical treatment. The aim of this review was to perform a systematic search of the Pub Med literature to reveal the evidence on scoliosis surgery.

METHODS

A systematic review has been performed using the Pub Med database. Literature has been searched for the outcome parameter; 'rate of progression' and only prospective controlled studies that have considered the treatment versus the natural history have been included.

RESULTS

No controlled study, not in the short, mid or long term, searched within the review, has been found to reveal evidence to support the hypothesis that the effects of surgery as a treatment option for AIS is superior to natural history.

CONCLUSIONS

No evidence has been found in terms of prospective controlled studies to support surgical intervention from the medical point of view. In the light of the unknown long-term effects of surgery and in concluding on the lack of evidence already found that surgery might change the signs and symptoms of scoliosis, a randomized controlled trial (RCT) is long overdue. Until such a time that such evidence exists, there can be no medical indication for surgery. The indications for surgery are limited for cosmetic reasons in severe cases and only if the patient and the family agree with this.