The efficacy of anterior vertebral body tethering in lenke type 6 curves for adolescent idiopathic scoliosis.

PURPOSE: Spinal fusion is the standard treatment for severe forms of adolescent idiopathic scoliosis (AIS). However, with the lowest instrumented vertebra that is usually located at L3 or L4, patients are prone to develop adjacent segment degeneration in the long term. Vertebral body tethering (VBT) as motion preserving technique has become an alternative for select patients with AIS. Several studies have presented the outcome after thoracic VBT but no study has analyzed the outcome after VBT for Lenke type 6 curves. METHODS: This is a retrospective single center data analysis of patients who have had bilateral VBT for Lenke type 6 curves and a minimum follow up of 24 months. Radiographic analysis was performed on several time points. Suspected tether breakages were additionally analyzed with respect to location and time at occurrence. RESULTS: 25 patients were included. Immediate thoracic curve correction was 55.4% and 71.7% for TL/L curves. Loss of correction was higher for TL/L curves and resulted in a correction rate of 48.3% for thoracic curves and 48.9% for TL/L curves at 24 months post-operatively. 22 patients were suspected to have at least one segment with a tether breakage. Three patients required a re-VBT but no patient received posterior spinal fusion. CONCLUSION: Bilateral VBT for Lenke type 6 curves is feasible and shows a significant curve correction for thoracic and TL/L curves at a minimum of 24 months post-operatively. Tether breakage rate and loss of correction remain an unfavorable observation that needs to be improved in the future.

Radiological Outcomes of Re-tethering for Adolescent Idiopathic Scoliosis: A 2-to-5-year Follow-Up Case Series After Index Vertebral Body Tethering Failure.

PURPOSE: Vertebral Body Tethering (VBT) has been shown to have a less predictable outcome compared to spinal fusion in patients with adolescent idiopathic scoliosis (AIS). Tether breakage is a common mechanical event that sometimes leads to loss of correction. No data has been published that evaluates the outcome of re-tethering in patients who underwent revision surgery for failed VBT, which was the purpose of this study. METHODS: This is an analysis of a prospectively collected single center database of 290 patients who have had VBT. Patients for this study were included if they have had re-tethering after failed VBT and a minimum follow up of 24 months after index surgery as well as a minimum follow up of 12 months after revision surgery. Revision surgeries included tether exchange, tether reinforcement and/or mono- and bisegmental lateral fusion. Main outcome of interest was curve magnitude at latest follow up. RESULTS: 11 patients were identified who received VBT for 16 curves of which 13 curves have had failed index surgery. Mean follow up from index surgery was 40 months, time between index and revision surgery was 22 months and latest follow up after revision surgery 19 months. Re-tethering resulted in an additional correction of 42% for thoracic and 63% for thoracolumbar curves. These results remained clinically stable with only minor loss of correction at final follow up. No patient underwent or was indicated for spinal fusion. CONCLUSION: Re-tethering is feasible and able to achieve additional correction and a sustainable result.

Early-term outcome of apical fusion with vertebral body tethering for thoracolumbar curves in adolescent idiopathic scoliosis: a preliminary study.

INTRODUCTION: Vertebral body tethering (VBT) has become an alternative option for select patients with idiopathic scoliosis. However, studies have shown a high number of tether breakages, specifically after thoracolumbar (TL) VBT, that can have a negative impact on the outcome, when the breakage occurs within the first year after surgery. In order to overcome this problem, we have started to apply an apical fusion (AF) in combination with TL VBT for select patients. This study aims to analyze the outcome after AF plus VBT. METHODS: This is a retrospective single surgeon's data analysis. All patients were included who have had TL VBT after January 2022 and a follow-up of 12 months. Patients were grouped based on whether they only had VBT or VBT + AF. RESULTS: Twenty-five patients were analyzed (15 VBT, 10 VBT + AF). Both groups showed a significant curve correction for thoracic and TL curves. Minor loss of correction was observed in both groups. A significant difference was seen regarding early tether breakages, which were found in 60% of VBT patients and 10% of VBT + AF patients. CONCLUSION: The preliminary data shows a significant reduction of early tether breakages when TL VBT is applied in combination with AF.

Assessing the Reproducibility of the Structured Abstracts Generated by ChatGPT and Bard Compared to Human-Written Abstracts in the Field of Spine Surgery: Comparative Analysis.

BACKGROUND: Due to recent advances in artificial intelligence (AI), language model applications can generate logical text output that is difficult to distinguish from human writing. ChatGPT (OpenAI) and Bard (subsequently rebranded as "Gemini"; Google AI) were developed using distinct approaches, but little has been studied about the difference in their capability to generate the abstract. The use of AI to write scientific abstracts in the field of spine surgery is the center of much debate and controversy. OBJECTIVE: The objective of this study is to assess the reproducibility of the structured abstracts generated by ChatGPT and Bard compared to human-written abstracts in the field of spine surgery. METHODS: In total, 60 abstracts dealing with spine sections were randomly selected from 7 reputable journals and used as ChatGPT and Bard input statements to generate abstracts based on supplied paper titles. A total of 174 abstracts, divided into human-written abstracts, ChatGPT-generated abstracts, and Bard-generated abstracts, were evaluated for compliance with the structured format of journal guidelines and consistency of content. The likelihood of plagiarism and AI output was assessed using the iThenticate and ZeroGPT programs, respectively. A total of 8 reviewers in the spinal field evaluated 30 randomly extracted abstracts to determine whether they were produced by AI or human authors. RESULTS: The proportion of abstracts that met journal formatting guidelines was greater among ChatGPT abstracts (34/60, 56.6%) compared with those generated by Bard (6/54, 11.1%; P<.001). However, a higher proportion of Bard abstracts (49/54, 90.7%) had word counts that met journal guidelines compared with ChatGPT abstracts (30/60, 50%; P<.001). The similarity index was significantly lower among ChatGPT-generated abstracts (20.7%) compared with Bard-generated abstracts (32.1%; P<.001). The AI-detection program predicted that 21.7% (13/60) of the human group, 63.3% (38/60) of the ChatGPT group, and 87% (47/54) of the Bard group were possibly generated by AI, with an area under the curve value of 0.863 (P<.001). The mean detection rate by human reviewers was 53.8% (SD 11.2%), achieving a sensitivity of 56.3% and a specificity of 48.4%. A total of 56.3% (63/112) of the actual human-written abstracts and 55.9% (62/128) of AI-generated abstracts were recognized as human-written and AI-generated by human reviewers, respectively. CONCLUSIONS: Both ChatGPT and Bard can be used to help write abstracts, but most AI-generated abstracts are currently considered unethical due to high plagiarism and AI-detection rates. ChatGPT-generated abstracts appear to be superior to Bard-generated abstracts in meeting journal formatting guidelines. Because humans are unable to accurately distinguish abstracts written by humans from those produced by AI programs, it is crucial to exercise special caution and examine the ethical boundaries of using AI programs, including ChatGPT and Bard.

The use of electronic conductivity devices can effectively reduce radiation exposure in vertebral body tethering.

INTRODUCTION: Vertebral body tethering (VBT) presents new challenges in respect to radiation exposure, as screws cannot be placed free-hand and the lateral positioning of the patients increases scattered radiation. To reduce radiation exposure, we introduced the use of electronic conductivity device (ECD). These are drilling probes send an audio signal when cortical bone is breached. Thus, anterior, bicortical screws can be placed without multiple fluoroscopic controls. ECD has been used for all VBT procedures at our institution starting April 2020. The aim of this study was to test the safety of ECD and its efficacy in radiation reduction in comparison with the current standard, the fluoroscopic guidance. MATERIALS AND METHODS: All patients who underwent VBT between August 2019 and December 2020 were retrospectively reviewed and divided into two groups according to whether ECD had been used or not. The radiation exposure per procedure and per screw was compared among the two groups, overall and separately for thoracic, lumbar and bilateral procedures. The rate of misplaced screws was calculated. RESULTS: Data from 62 patients and 825 screws were obtained (397 with ECD). No screw misplacement was observed. Radiation reduction with ECD reached up to 41%. A significant reduction was observed in the radiation per procedure in bilateral instrumentation (from 9.16 to 5.52 mGy*m2), and in the analysis per screw overall (from 9.16 to 5.52 mGy*m2) and for lumbar curves (from 0.54 to 0.32 mGy*m2). CONCLUSION: ECD can safely and effectively reduce the radiation exposure for VBT procedures.

Radiographic outcome after vertebral body tethering of the lumbar spine.

INTRODUCTION: Multiple studies have analyzed the outcome after thoracic Vertebral Body Tethering (VBT). The results seem reproducible with most studies reporting coronal correction rates around 50% and a tether breakage rate near 20% at two years follow-up. There is a paucity of data on lumbar VBT, and no study has yet analyzed the radiographic outcome after lumbar VBT in a double tether technique at two years follow-up, which was the aim of this study. METHODS: This is a retrospective, single surgeons' data analysis of all consecutive immature patients who have had VBT of the lumbar spine (to L3 or L4) between January 2019 and September 2020. Primary interest focused on coronal curve correction at two years post-operatively. Suspected tether breakages were analyzed separately and defined as an angular change of more than 5° between two adjacent screws. RESULTS: Forty-one patients were eligible for this study and 35 (85%) had complete two-year follow-up data. Average age at surgery was 14.3 years. All patients had a Sanders stage of 7 or below. Average curve correction for thoracolumbar/lumbar curves at two years follow-up was 50%. 90% of patients had at least one level with a suspected tether breakage. No patient required a revision surgery within two years from surgery but two patients were surgically revised after two years. CONCLUSION: VBT in the lumbar spine resulted in 50% coronal curve correction two years post-operatively despite a tether breakage in 90% of patients.

An investigation of range of motion preservation in fusionless anterior double screw and cord constructs for scoliosis correction.

PURPOSE: To evaluate the motion-preserving properties of vertebral body tethering with varying cord/screw constructs and cord thicknesses in cadaveric thoracolumbar spines. METHODS: In vitro flexibility tests were performed on six fresh-frozen human cadaveric spines (T1-L5) (2 M, 4F) with a median age of 63 (59-to-80). An ± 8 Nm load was applied to determine range of motion (ROM) in flexion-extension (FE), lateral bending (LB), and axial rotation (AR) in the thoracic and lumbar spine. Specimens were tested with screws (T5-L4) and without cords. Single (4.0 mm and 5.0 mm) and double (4.0 mm) cord constructs were sequentially tensioned to 100 N and tested: (1) Single 4.0 mm and (2) 5.0 mm cords (T5-T12); (3) Double 4.0 mm cords (T5-12); (4) Single 4.0 mm and (5) 5.0 mm cord (T12-L4); (6) Double 4.0 mm cords (T12-L4). RESULTS: In the thoracic spine (T5-T12), 4.0-5.0 mm single-cord constructs showed slight reductions in FE and 27-33% reductions in LB compared to intact, while double-cord constructs showed reductions of 24% and 40%, respectively. In the lumbar spine (T12-L4), double-cord constructs had greater reductions in FE (24%), LB (74%), and AR (25%) compared to intact, while single-cord constructs exhibited reductions of 2-4%, 68-69%, and 19-20%, respectively. CONCLUSIONS: The present biomechanical study found similar motion for 4.0-5.0 mm single-cord constructs and the least motion for double-cord constructs in the thoracic and lumbar spine suggesting that larger diameter 5.0 mm cords may be a more promising motion-preserving option, due to their increased durability compared to smaller cords. Future clinical studies are necessary to determine the impact of these findings on patient outcomes.

Difference between radiographically suspected and intraoperatively confirmed tether breakages after vertebral body tethering for idiopathic scoliosis.

PURPOSE: Vertebral body tethering (VBT) has shown promising results but also a high tether breakage rate, which has been reported in up to 48% of patients. Tether breakages can lead to loss of correction, and the most used definition for tether breakage is a loss of segmental correction of > 5°. However, there may also be some breakages that do not have a negative influence on curve correction. Analyzing the real breakage rate was the aim of this study. METHODS: All patients who underwent anterior revision surgery after VBT were included in this retrospective study. Real (intraoperatively confirmed) tether breakages were compared to preoperatively suspected tether breakages. The definition for a suspected tether breakage was an angular change of more than 5° between an early and the latest radiograph. RESULTS: Ten patients who received 11 revision surgeries with a total of 15 revised curves were analyzed. Of the 80 analyzed segments, 36 were found to have a breakage. Of these 36 segments, 20 were suspected to be broken preoperatively. Sixteen breakages were not identified on preoperative radiographs (44%). One suspected broken tether was intraoperatively found to be intact. CONCLUSION: By using the > 5° rule, only 56% of the tether breakages could be diagnosed. On the other hand, many tether breakages will not result in a loss of correction.

Analysis of the pulmonary function in patients undergoing vertebral body tethering for adolescent idiopathic scoliosis.

PURPOSE: The literature concerning the effects of scoliosis correction on pulmonary function (PF) is scarce and solely related to spinal fusion. Vertebral body tethering (VBT) represents a new option for scoliosis correction; however, its effects on PF have not yet been investigated. As VBT is a fusion-less technique that does not limit the dynamics of the chest wall, it is expected not to have a negative impact on PF despite the anterior surgical approach. METHODS: We analyzed the PF preoperatively and compared it with the PF at 6-weeks, 6-months and 12-monthts postoperatively. Considered parameters were total lung capacity (TLC), forced expiratory volume in 1 s (FEV1) and forced vital capacity (FVC) expressed as percentages. A change of more than 10% was considered clinically significant. RESULTS: Before VBT, overall TLC, FEV1 and FVC measured 98 ± 15%, 85 ± 16% and 91 ± 17%, respectively. Six weeks after surgery, all parameters were comparable to the preoperative values (TLC 96 ± 17%, FEV1 84 ± 14%, FVC 90 ± 16%) and remained so at the last follow-up (TLC 99 ± 15%, FEV1 89 ± 9%, FVC 86 ± 9). While a reduction in FEV1 and FVC was observed at 6-weeks and 6-months in patients with thoracic or double curves compared to thoracolumbar curves, no significant differences were observed at the 12-months follow-up. CONCLUSIONS: VBT does not cause a reduction in PF values at a short-term follow-up.

The effects of vertebral body tethering on sagittal parameters: evaluations from a 2-years follow-up.

INTRODUCTION: While the effects of VBT on coronal parameters have been investigated in various studies, this has not yet been the case for sagittal parameters. This is of particular relevance considering that VBT does not allow direct correction of the sagittal profile. Thus, we investigated the effects of VBT on sagittal parameters in patients with adolescent idiopathic scoliosis. MATERIALS AND METHODS: Retrospective, 2-Center study. Patients who underwent VBT and presented a 2-years follow-up were included. The differences in sagittal parameters were evaluated, along with modifications of sagittal profile following Abelin-Genevois' classification. RESULTS: Data from 86 patients were obtained. Mean Cobb angle was 52.4 ± 13.9° at thoracic level and 47.6 ± 14.3° at lumbar level before surgery, and 28.5 ± 13.6 and 26.6 ± 12.7° at the 2-year follow-up, respectively. Mean thoracic kyphosis increased from 28.3 ± 13.8 to 33 ± 13°, the lumbar lordosis (LL) was unvaried (from 47.5 ± 13.1 to 48.4 ± 13.5°), PT decreased from 9.4 ± 8.5 to 7.4 ± 6.1°, the sagittal vertical axis SVA decreased from 4.5 ± 31.4 to - 3.6 ± 27.9 mm. No kyphotic effect on LL in patients who underwent lumbar instrumentation was observed. Before surgery, 39 patients had a type 1 sagittal profile, 18 were type 2a, 14 type 2b and 15 type 3. Postoperatively, 54 were type 1, 8 were 2a, 13 were 2b and 11 were type 3. CONCLUSIONS: VBT positively influences sagittal parameters and does not have a kyphotic effect on LL.

Motion preservation surgery for scoliosis with a vertebral body tethering system: a biomechanical study.

PURPOSE: There is a paucity of studies on new vertebral body tethering (VBT) surgical constructs especially regarding their potentially motion-preserving ability. This study analyses their effects on the ROM of the spine. METHODS: Human spines (T10-L3) were tested under pure moment in four different conditions: (1) native, (2) instrumented with one tether continuously connected in all vertebrae from T10 to L3, (3) additional instrumented with a second tether continuously connected in all vertebrae from T11 to L3, and (4) instrumented with one tether and one titanium rod (hybrid) attached to T12, L1 and L2. The instrumentation was inserted in the left lateral side. The intersegmental ROM was evaluated using a magnetic tracking system, and the medians were analysed. Please check and confirm the author names and initials are correct. Also, kindly confirm the details in the metadata are correct. The mentioned information is correct RESULTS: Compared to the native spine, the instrumented spine presented a reduction of less than 13% in global ROM considering flexion-extension and axial rotation. For left lateral bending, the median global ROM of the native spine (100%) significantly reduced to 74.6%, 66.4%, and 68.1% after testing one tether, two tethers and the hybrid construction, respectively. In these cases, the L1-L2 ROM was reduced to 68.3%, 58.5%, and 38.3%, respectively. In right lateral bending, the normalized global ROM of the spine with one tether, two tethers and the hybrid construction was 58.9%, 54.0%, and 56.6%, respectively. Considering the same order, the normalized L1-L2 ROM was 64.3%, 49.9%, and 35.3%, respectively. CONCLUSION: The investigated VBT techniques preserved global ROM of the spine in flexion-extension and axial rotation while reduced the ROM in lateral bending.

Preliminary outcomes after vertebral body tethering (VBT) for lumbar curves and subanalysis of a 1- versus 2-tether construct.

INTRODUCTION: Aim of this study was to analyze the rate of tether breakages after lumbar vertebral body tethering (VBT) and to study the effects and possible benefits of the use of a 2-tether construct. Tether breakage is a known mechanical complication after VBT. However, the literature only refers to thoracic VBT, and no data on the breakage rate or 2-tether construct after lumbar VBT are available. MATERIALS AND METHODS: Patients who underwent lumbar VBT with lowest instrumented vertebra at L3 or L4 and had a 1-year follow-up were included. Radiologic data were obtained preoperatively, at the 1st standing X-ray and at the 1-year follow-up to study breakage rate, loss of correction and lumbar lordosis in 1- and 2-tether constructs. RESULTS: Data from 30 patients (mean age 14.7 ± 1.8) were available, 12 with double tether. Double tether did not decrease lumbar lordosis. The breakage rate was 24% in segments instrumented with a single tether and 16% in segments instrumented with a double tether (OR 1.6, p = 0.4). Lumbar loss of correction was 10° ± 6.8° in the entire cohort and 12.1° ± 5.4° in patients with a breakage (p = 0.2). Revision rate was 10%, due to tether breakage and loss of correction. CONCLUSION: Breakage rate after lumbar VBT is high, but was improved with the use of a 2-tether construct. Despite tether breakage, loss of correction was limited and the revision rate low. The use of a double tether does not have a kyphotic effect on the lumbar spine.

Return to sport and daily life activities after vertebral body tethering for AIS: analysis of the sport activity questionnaire.

PURPOSE: Vertebral body tethering (VBT) is an alternative to fusion for selected scoliosis patients. As VBT does not limit spine mobility, it has been propagated that this technique allows a quicker return to physical activity than fusion. However, no data are available to support this statement. Aim of this study was to quantify how much time patients required to resume preoperative activity level and to seek possible associations between return to physical activity and demographic, radiographic and surgical data. METHODS: One year postoperatively, the validated sport activity questionnaire (SAQ) was administered to all skeletally immature patients who underwent VBT at our institution. SAQ data were analyzed and a multivariate analysis was conducted to investigate associations between SAQ and demographic, radiographic and surgical data. RESULTS: Thirty-one patients aged 14.5 years completed the SAQ. Within 3 months from VBT, 97% returned to school, 61% resumed physical education, 97% carried a backpack, 68% run, and 82% rode a bike; 70% bent within a month from VBT. Ninety-four percent of patients returned to their preoperative athletic level. Within 3 months, 63% of responders resumed noncontact, 61% contact and 53% collision sports. No relevant associations were observed between the SAQ and demographic, radiographic and surgical data. In particular, number of instrumented vertebrae, level of the lowest instrumented vertebra and postoperative Cobb angle did not influence patients' return to preoperative activities. CONCLUSION: VBT allows patients to quickly return to their preoperative activity level, irrespectively of the postoperative Cobb angle or type of instrumentation.

[Posttraumatic deformity of the thoracolumbar spine]. / Posttraumatische Fehlstellungen der Brust- und Lendenwirbelsäule.

Posttraumatic kyphotic deformities of the thoracolumbar spine may result in significant clinical complaints. If conservative treatment is not successful, surgical correction of the kyphosis becomes an option. In contrast to degenerative deformities, posttraumatic kyphotic deformities are usual limited to few segments and can be treated with shorter constructs. The surgical strategy depends on the rigidity and the localization of the posttraumatic kyphotic deformity. In this respect purely posterior approaches and combined posteroanterior surgical approaches are available each with different advantages and disadvantages.

PSO without neuromonitoring: analysis of peri-op complication rate after lumbar pedicle subtraction osteotomy in adults.

PURPOSE: A decompensated sagittal imbalance has been associated with worsening health-related quality of life outcomes and increasing pain. Significant improvement in sagittal balance can be achieved using a pedicle subtraction osteotomy (PSO); however, this procedure has a high complication profile. A lumbar PSO has the advantages of direct visualization of all neural structures and safer retraction of the thecal sac. Sacrificing neuromonitoring may reduce anaesthesia time and lead to improved cost effectiveness of the surgery. However, there are no studies analyzing the complication rate of lumbar PSO without the use of neuromonitoring. We hypothesize that the neurologic complication rate remains comparable to published studies even without the use of intraoperative neuromonitoring. METHODS: The medical records of all patients of a single institution who received a lumbar PSO for sagittal imbalance between July 2012 and June 2014 were retrospectively analyzed. All surgeries were performed by the first author and without the use of intraoperative neuromonitoring. We analyzed the 30-day complication rate. RESULTS: Twenty-two patients were included in this study. The average age at surgery was 67 years. 16 patients had at least one previous lumbar surgery. The average fusion length was seven segments. All patients were instrumented to the sacrum and 19 patients additionally received spinopelvic instrumentation. The average amount of focal correction was 28°. The average surgical time was 362 min and blood loss was 2302 mL. A total of eight patients with complications were identified. There was a new neurologic postoperative deficit in two patients presenting as a foot drop. Five patients had an unplanned revision surgery. CONCLUSION: Historically, PSOs are associated with a high surgical complication rate and our results show comparable outcomes and complications to those previously reported. In our series, the absence of neuromonitoring in lumbar PSOs does not appear to increase the risk of neurological injury.

Dynamic Adduction Angle of Forefoot Measured With a Novel Technique And Its Relationship With Functional Outcomes.

BACKGROUND: Idiopathic clubfoot is commonly treated with the Ponseti method with the extent of invasive treatment involving tendon-Achilles lengthening. Forefoot adduction is a common complication in surgically treated clubfeet. Yet, no method has been described to measure dynamic (walking) forefoot adduction. The aim of this study was to assess the persistent pes adductus in children whose clubfeet were surgically treated using a dorsomedial soft tissue release and to find out correlations between forefoot adduction and clinical outcome measures. METHODS: We analysed the dynamic adduction angle in 33 clubfeet using a pressure-sensitive foot platform and compared it to the healthy feet of an age- and weight-matched group of children without congenital foot deformities. The clinical outcome was analysed using the McKay score. RESULTS: Mean dynamic adduction angle was 4.1o in the surgically corrected clubfeet, whereas it was 6.4° in unaffected feet of patients with unilateral clubfoot and 7.1o in control group. The McKay score were excellent in 1 patient, good in 5, average in 13, and fair in 4 of the 23 patients. There was no correlation between dynamic adduction angle and McKay score using paired t test (P > 0.05). CONCLUSION: High occurrence of dynamic adduction angle in surgically treated clubfeet was detected. In conclusion, no correlation between forefoot adduction, dynamic forefoot adduction angle and clinical outcome measures within the study was observed.

Surgical aspects of spinal growth modulation in scoliosis correction.

Spine growth modulation for scoliosis correction is a technique for slowing growth on the convex side of the curve and enhancing growth on the concave side by using the Heuter-Volkmann principle; this results in gradual deformity correction. The theoretic advantages include speedier recovery because of the minimally invasive approach used, as well as motion preservation. Several devices have been used in humans, including vertebral body stapling, with either a flexible titanium clip or a nitinol staple, and anterior spinal tethering. Prerequisites for the use of these devices are a relatively flexible curve and sufficient remaining growth in the patient. Although vertebral body stapling is effective for moderate curves of less than 40°, anterior spinal tethering can be used for curves greater than 40°. The titanium clip and spinal tethers are used exclusively for thoracic scoliosis, whereas nitinol staples can be used for the thoracic spine or the lumbar spine. The thoracoscopic technique is used for thoracic instrumentation, and the mini-open retroperitoneal technique is used for lumbar staple insertion. The insertion of a titanium clip and an anterior spinal tether requires sacrifice and mobilization of the segmental vessels, whereas nitinol staples can be inserted without such sacrifice. Single lung ventilation and CO2 insufflation are used to improve visualization with the thoracoscope. The curve should be instrumented from an end vertebra to an end vertebra. Postoperative immobilization depends on the type of device used. Most complications are approach related, such as atelectasis caused by a mucus plug, pain at the chest tube site, and pneumothorax. Device-related complications are rare. Overcorrection is a concern. In patients with early onset scoliosis, a hybrid construct with vertebral stapling and growing rods or a vertical expandable prosthetic titanium rib has been suggested. A failure of the spinal growth modulation procedure does not preclude spinal fusion. None of the devices for spine growth modulation have been approved by the FDA for human use and are still investigational. Early results are promising, and continued clinical studies are necessary.

The Mid-term Outcome of Intervertebral Disc Degeneration after Direct Vertebral Rotation in Adolescent Idiopathic Scoliosis: Magnetic Resonance Imaging-based Analysis for a Mean 11.6-year Follow-up.

STUDY DESIGN: A retrospective cohort study. OBJECTIVE: To evaluate the mid-term effect of intervertebral disc degeneration (DD) in adolescent idiopathic scoliosis (AIS) patients who underwent pedicle screw instrumentation (PSI) and rod derotation (RD) with direct vertebral rotation (DVR). SUMMARY OF BACKGROUND DATA: Posterior spinal fusion is a mainstay of surgical treatment in AIS, and DVR is considered a main corrective maneuver for vertebral rotation. However, the mid-term effect of intervertebral DD after DVR is still unknown in AIS. METHODS: A total of 336 vertebrae for 48 AIS patients who underwent PSI and RD with DVR were retrospectively assessed for intervertebral DD. They were divided into two groups based upon intervertebral DD, defined as Pfirmann grade more than IV. The Pfirrmann grade and modic change were evaluated at the disc above the uppermost instrumented vertebra (UIV), the disc below the lowest instrumented vertebra (LIV), and the lumbar disc levels. RESULTS: With the 11.6 years of mean follow-up, 41.7% (20/48) of patients exhibited DD, while modic changes were observed in 4.2% (2/48) of included patients. The disc below the LIV, L4-5, and L5-S1 were significantly shown to have an increasing trend of Pfirmann grade. The preoperative thoracic kyphosis was significantly lower in the DD group (22.0°) than in the non-DD group (31.4°) (P = 0.025) and negatively correlated with DD (r = -0.482, P = 0.018). The Pfirrmann grade of L5-S1 showed a high level of correlation with DD (r = 0.604, P < 0.001). CONCLUSIONS: The degenerative change at the disc below the LIV, L4-5, and L5-S1 levels was observed following PSI and RD with DVR. Thoracic hypokyphosis may negatively influence intervertebral discs in AIS patients required for deformity correction. Therefore, restoration of thoracic kyphosis is important to prevent long-term DD in AIS.

Adolescent Idiopathic Scoliosis: Is the Feasible Option of Minimally Invasive Surgery using Posterior Approach?

The purpose of this systematic review and meta-analysis is to perform a systematic review and meta-analysis of previous studies on minimally invasive scoliosis surgery (MISS) in adolescents with idiopathic scoliosis (AIS). Some data on MISS in AIS compared with conventional open scoliosis surgery (COSS) are conflicting. A systematic literature search was conducted in Medline, Embase, and Cochrane Library, including studies reporting outcomes for MISS in AIS. The meta-analysis compared the operative, radiological, and clinical outcomes and complications between MISS and COSS in patients with AIS. Of the 208 records identified, 15 nonrandomized studies with 1,369 patients (reviews and case reports are excluded) were included in this systematic review and meta-analysis. The mean scale was 6.1, and eight of the 15 included studies showed satisfactory quality using the Newcastle-Ottawa scale. For operative outcomes, MISS had significant benefits in terms of estimated blood loss (standard mean difference [SMD], -1.87; 95% confidence interval [CI], -2.94 to -0.91) and hospitalization days (SMD, -2.99; 95% CI, -4.45 to -1.53) compared with COSS. However, COSS showed significantly favorable outcomes for operative times (SMD, 1.71; 95% CI, 0.92-2.51). No significant differences were observed in radiological outcomes, including Cobb's angle of the main curve and thoracic kyphosis. For clinical outcomes, MISS showed significant benefits on the visual analog scale score (SMD, -0.91; 95% CI, -1.36 to -0.47). The overall complication rates of MISS were similar to those of COSS (SMD, 0.96; 95% CI, 0.61-1.52). MISS using the posterior approach provides equivalent radiological and clinical outcomes and complication rates compared with COSS. Considering the lower estimated blood loss, shorter hospitalization days, and longer operative times in MISS, COSS is still the mainstay of surgical treatment in AIS; however, MISS using the posterior approach is also one of the surgical options of choice in the case of moderate AIS.