Instrumentation For Scoliosis Research Articles

Intravenous lidocaine infusion therapy and intraoperative neurophysiological monitoring in adolescents undergoing idiopathic scoliosis correction: A retrospective study.

Posterior spinal instrumentation and fusion is an established surgical procedure for the correction of adolescent idiopathic scoliosis. Intraoperative neurophysiological monitoring is standard practice for this procedure. Anesthetic agents can have different, but significant, effects on neurophysiological monitoring outcomes. To determine if intravenous lidocaine infusion therapy has an impact on the intraoperative neurophysiological monitoring during posterior spinal instrumentation and fusion for adolescent idiopathic scoliosis. Following ethical approval, we conducted a retrospective review of charts and the archived intraoperative neurophysiological data of adolescents undergoing posterior spinal instrumentation and fusion for adolescent idiopathic scoliosis. Intraoperative neurophysiological monitoring data included the amplitude of motor evoked potentials and the amplitude and latency of somatosensory evoked potentials. A cohort who received intraoperative lidocaine infusion were compared to those who did not. Eighty-one patients were included in this analysis, who had surgery between February 4, 2016 and April 22, 2021: 39 had intraoperative intravenous lidocaine infusion and 42 did not. Based on hourly snapshot data, there was no evidence that lidocaine infusion had a detrimental effect on the measured change from baseline for MEP amplitudes in either lower (mean difference 41.9; 95% confidence interval -304.5 to 388.3; p = .182) or upper limbs (MD -279.0; 95% CI -562.5 to 4.4; p = .054). There was also no evidence of any effect on the measured change from baseline for SSEP amplitudes in either lower (MD 16.4; 95% CI -17.7 to 50.5; p = .345) or upper limbs (MD -2.4; 95% CI -14.5 to 9.8; p = .701). Finally, there was no evidence of a difference in time to first reportable neurophysiological event (hazard ratio 1.13; 95% CI 0.61 to 2.09; p = .680). Data from these two cohorts provide preliminary evidence that intravenous lidocaine infusion has no negative impact on intraoperative neurophysiological monitoring during PSIF for adolescent idiopathic scoliosis.

Three-dimensional deformity correction in adolescent idiopathic scoliosis patients: what are the benefits of hybrid apical sublaminar bands versus all-pedicle screws?

The amount of three-dimensional (3D) correction with apical sublaminar band (hybrid-SLB) technique has not been compared to all-pedicle screw instrumentation for adolescent idiopathic scoliosis (AIS) using detailed axial correction metrics or comparable rod types. Our purpose is to compare 3D improvement in AIS deformities following posterior spinal instrumentation and fusion (PSIF) with hybrid-SLB and segmental correction to all-pedicle screw correction. Patients ages 10-18 years with AIS who underwent PSIF between 2015 and 2022 and had preoperative and postoperative EOS imaging were included. Electronic medical records were reviewed for demographic, Lenke classification, operative technique, and 3D EOS data. Average changes in major and minor Cobb angle, axial rotation, thoracic kyphosis, and lumbar lordosis were compared. Ninety-five patients met inclusion criteria with 55 in the hybrid-SLB group (mean age 14.9 ± 1.9 years) and 40 in all-pedicle screw (mean age 14.7 ± 2.1 years). While all-pedicle screw demonstrated greater correction of major (45.7 ± 13.4 vs 37.9 ± 14.3 degrees; P = 0.008) and minor (28.7 ± 13.1 vs 17.8 ± 12.5 degrees; P = 0.001) Cobb angles, hybrid-SLB showed greater increase in T4-T12 kyphosis (13.3 ± 15.3 vs 5.6 ± 13.5 degrees; P = 0.01). Correction of T1-T12 kyphosis, axial rotation, and lumbar lordosis was similar between groups. 3D EOS analysis of AIS patients before and after PSIF revealed that all-pedicle screw constructs had greater overall coronal plane correction and hybrid-SLB had greater thoracic sagittal plane correction. Axial corrective abilities were similar. Hybrid-SLB may have advantages for correction of thoracic lordosis or hypokyphosis. Level of evidence: Level III, retrospective cohort study.

Association between underweight status or low body mass index and the risk of developing superior mesenteric artery syndrome following scoliosis corrective surgery in pediatric patients: a review of the literature

Superior mesenteric artery (SMA) syndrome is the compression of the third portion of the duodenum between the abdominal aorta and the superior mesenteric artery. Although multifactorial, the most frequent cause of SMA syndrome is significant weight loss and cachexia often induced by catabolic stress. SMA syndrome resulting from scoliosis surgery is caused by a reduction of the aortomesenteric angle and distance. Risk factors include rapid weight loss, malnutrition, and a rapid reduction in the mesenteric fat pad and are the most common causes of a decrease in the aortomesenteric angle and distance. Surgically lengthening the vertebral column can also lead to a reduction of the aortomesenteric distance, therefore, has been identified as a risk factor unique to spinal surgery. Despite a reported decline in SMA syndrome cases due to improved surgical techniques, duodenal compression is still a risk and remains a life-threatening complication of scoliosis surgery. This article is a cumulative review of the evidence of being underweight or having a low body mass index as risk factors for developing SMA syndrome following surgical scoliosis instrumentation and correction.

Placement of ilio-sacral screws in fusionless technique for pediatric neuromuscular scoliosis utilizing planning software, in conjunction with intraoperative navigation, results in a safer optimal screw: a CT-based study.

The insertion of ilio-sacral (IS) screws for distal anchoring in the instrumentation of pediatric neuromuscular scoliosis (NS) presents a significant challenge, often leading to elevated rates of complications. Utilizing computed tomography (CT) navigation and preoperative planning technology is proposed as a potential solution to mitigate these challenges. This study aims to assess the precision of IS screw placement through CT-graphic measurements, both with and without preoperative planning, followed by navigated IS screw insertion, in pediatric neuromuscular scoliosis. Thirty-two treated patients were grouped based on surgical procedure: planned (P): 19 patients (n=38 screws) and non-planned (NP): 13 patients (n=26 screws). All screw placements (P and NP) took place under CT navigation. IS screw trajectories of P-group were drawn preoperatively on CT images with the cranial trajectory planning program and fused with the intraoperative CT images. There are several important anatomical structures that should be avoided when placing the IS screw (L5 root, spinal canal, L5S1 facet, SI joint, neurovascular structures anteriorly to the sacrum, S1 root in the S1 foramen and the intestines). Each trajectory was evaluated based on seven radiographical parameters whom we have enlisted partially based on the essentials of a good trajectory described by Miladi et al. (1: Ilium; 2: SI joint; 3: Promontorium; 4: Sacral plate; 5: Anterior sacral cortex; 6: S1 foramen; 7: Spinal canal). An independent sample T test was executed to compare both groups. The trajectories in the P group showed a significantly (P<0.05) higher overall similarity and optimality (12.1±2.1 vs 9.1±2.2 points) compared to the non-planned trajectory. Preoperative planning and navigated placement of IS screws on fusion images with intraoperative CT, results in a better trajectory of the ilio-sacral screws.

Radiographic and clinical outcomes of robot-assisted pedicle screw instrumentation for adolescent idiopathic scoliosis.

Pedicle screw instrumentation (PSI) serves as the widely accepted surgical treatment for adolescent idiopathic scoliosis (AIS). The accuracy of screw positioning has remarkably improved with robotic assistance. Nonetheless, its impact on radiographic and clinical outcomes remains unexplored. This study aimed to investigate the radiographic and clinical outcomes of robot-assisted PSI vs. conventional freehand method in AIS patients. Data of AIS patients who underwent PSI with all pedicle screws between April 2013 and March 2022 were included and retrospectively analyzed; those with hybrid implants were excluded. Recruited individuals were divided into the Robot-assisted or Freehand group according to the technique used. Radiographic parameters and clinical outcome measures were documented. In total, 50 patients (19, Freehand group; 31, Robot-assisted group) were eligible, with an average age and follow-up period of 17.6 years and 60.2 months, respectively, and female predominance (40/50, 80.0%). The correction rates of Cobb's angles for both groups were significant postoperatively. Compared to freehand, the robot-assisted technique achieved a significantly reduced breech rate and provided better trunk shift and radiographic shoulder height correction with preserved lumbar lordosis, resulting in significantly improved visual analog scale scores for back pain from the third postoperative month. Overall, robot-assisted PSI provides satisfactory radiographic and clinical outcomes in AIS patients.

Differential vertebral body growth is maintained after vertebral body tethering surgery for idiopathic scoliosis: 4-year follow-up on 888 peri-apical vertebrae and 592 intervertebral discs.

To radiographically evaluate if vertebral body tethering (VBT) can maintain differential peri-apical vertebral growth at medium-term follow-up of 4years. A prospective, international, multicenter database was queried to identify idiopathic scoliosis patients treated with thoracic VBT. Concave vs. convex vertebral body height, vertebral wedging, and disc wedging of the 3 peri-apical vertebrae were measured by two independent observers at 5 timepoints (pre-operative to 4-year follow-up). 65 skeletally immature patients (60 female, mean 12.8years old, 21 with open triradiate cartilages) met inclusion criteria. Mean pre-operative maximum scoliosis of 50 ± 8° decreased significantly post-operatively to 27 ± 9° (p < 0.001), which remained stable at 4-year follow-up 30 ± 17° (p = 0.38 vs. post-operative). Mean instrumented scoliosis was 21 ± 14° at 4-year follow-up, which was significantly different than 4-year maximum scoliosis (p < 0.001). Mean pre-operative kyphosis of 30 ± 12° did not significantly change post-operatively (p = 1.0) and remained stable at 4-year follow-up (35 ± 18°; p = 0.05). Mean individual convex vertebral height increased from 17.7 ± 1.9mm to 19.8 ± 1.5mm (p < 0.001), while mean individual concave height increased from 14.8 ± 1.9mm to 17.6 ± 1.6mm (p < 0.001). Summing the peri-apical heights, the difference in height from pre-operative to 4-year follow-up was greater on the concave (8.3 ± 4.7mm) than on the convex side (6.2 ± 4.7mm) (p < 0.001). Mean individual vertebral wedging decreased from 6 ± 2° at pre-operative to 4 ± 2° at 4-year follow-up (p < 0.001). Mean total vertebral and disc wedging started at 29 ± 7° pre-operatively, decreased to 16 ± 6° at post-operative (p < 0.001), then further decreased to 14 ± 8° at 4-year follow-up (p < 0.001). Patients with open triradiate cartilages at the time of surgery had a larger height change over the 4years compared to those with closed triradiate cartilages (p < 0.001). Patients with idiopathic scoliosis treated with VBT demonstrated differential vertebral growth which was maintained at minimum 4-year follow-up. This effect was more pronounced in patients whose triradiate cartilages were open at the time of surgery. III.

A Rare Case of Osteogenesis Imperfecta Type V

Osteogenesis imperfecta (OI) is a hereditary bone condition characterised by fragile bones to be more susceptible to fracture. We reported a rare case of a 6-year-old girl with OI Type V and hyperplastic callus formation. She presented with recurrent fractures since birth with no family history of a similar condition. Clinically, her height and weight were lower than the 5th percentile for her age. She had deformities with limitation of movement of elbows, kyphoscoliosis, a more extensive right thigh, and anterior bowing of both legs. Radiographic examination revealed interosseous membrane of forearm ossification, dislocation of the right radial head and hyper-callosity of both femurs during fracture healing. She was treated with intravenous pamidronate and had posterior instrumentation and fusion for scoliosis and intramedullary rodding for her femur fracture. On a recent follow-up at the age of 16 years, she was ambulating well with no progression of the spinal deformity.

Autofusion in early-onset scoliosis growing constructs: occurrence, risk factors, and impacts.

Autofusion (AF) during growing rod (GR) instrumentation for early-onset scoliosis (EOS) has been reported, but AF incidence, causation, and clinical implications remain unknown. This article aims to (1) quantify frequency and severity of AF, (2) determine risk factors for AF, and (3) assess the influence of AF on final curve correction and spinal lengthening. EOS patients were prospectively enrolled (2016-2021). Patients underwent evaluation, GR implantation, lengthenings, and posterior spinal fusion (PSF). Cobb angle and spinal length measurements were collected. AF was assessed and graded, with grades I-II being low-grade and III-V being high-grade. Exposure analysis quantified risk factors' impact via odds ratios and Pearson regression correlates. Statistical significance was p ≤ 0.05 or ≥ 0.95. 28 patients, with variable EOS diagnoses, were included. On average, GR were implanted at 8.54-year-old and lengthened over 4.66years. 53.6% of patients received magnetically controlled GR (MCGR) and 46.4% traditional GR (TGR). The average construct bridged 13.4 levels. Over the lengthening period, for all indications, patients averaged 2.9 total open procedures. Curves corrected from 68.5º preoperatively to 35.3º after index GR to 35.6º after PSF. Spinal length increased from 30.0cm preoperatively to 33.9cm after index GR to 39.5cm after PSF. AF grading was: 28.6% Grade I, 25.0% Grade II, 17.9% Grade III, 25.0% Grade IV, and 3.6% Grade V. Idiopathic EOS tended to have lower AF grades (p = 0.37). AF risk factors included GR age < 8 (10.4×, p = 0.01), any interval open procedures (6.3×, p = 0.05), and residual curve > 30º after index GR (13.7×, p = 0.02). Protective factors included preoperative spinal length of > 30.0cm (0.11×,p = 0.01) and index MCGR (0.16×, p = 0.03). Maintenance of Cobb angles from index GR through PSF was relatively better in low-grade patients (p = 0.08). Spinal length gained was no different between low- and high-grade AF (p = 0.50). This largest-to-date evaluation found AF is nearly ubiquitous in GR constructs, but with variable severity. Both risk factors and protective factors coincide with AF. Ultimately, even in high-grade AF, curve correction was maintained, and spinal lengthening was achieved. Level II-prospective cohort study.

The effect of surgical time on perioperative complications in adolescent idiopathic scoliosis cases. A propensity score analysis.

Posterior spinal instrumentation and fusion (PSIF) for adolescent idiopathic scoliosis (AIS) can be lengthy and complication-ridden. The aim of this study was to evaluate the effect of surgical time on perioperative complications in this procedure when controlling for confounding variables with propensity score analysis. This was an IRB-approved review of electronic health records from 2010 to 2019 at a single tertiary care children's hospital. Patients undergoing PSIF were grouped into "short" (< 6h) or "long" (≥ 6h) surgical time groups. Outcome measures were estimated blood loss (EBL), cell saver transfusions, packed red blood cell (pRBC) transfusions, length of stay (LOS), intraoperative monitoring (IOM) alerts, hematocrit, ICU transfer, neurologic loss, surgical site infection, and 90-day readmissions. We controlled for age, sex, BMI, curve severity, number of segments fused, and surgeon factors. After propensity score matching there were 113 patients in each group. The short surgical time group had lower EBL (median 715, IQR 550-900 vs median 875, IQR 650-1100cc; p < 0.001), received less cell saver blood (median 120, IQR 60-168 vs median 160, IQR 97-225cc; p = 0.001), received less intraoperative pRBCs (median 0, IQR 0-0 vs median 0, IQR 0-320, p = 0.002), had shorter average LOS (4.8 ± 1.7 vs 5.4 ± 2.5days; p = 0.039), and fewer IOM alerts (4.3% vs 18%, p = 0.003). Patients with shorter surgical times had less blood loss, received less transfused blood, had a shorter LOS, and fewer IOM alerts compared to patients with longer surgical times. Surgical times < 6h may have safety and efficacy advantages over longer times. III.

The length of scoliosis instrumentation affects the adjacent segmental flexibility and the lumbar intradiscal pressure: An in vitro study using entire thoracolumbar spine and rib cage specimens

The length of scoliosis instrumentation affects the adjacent segmental flexibility and the lumbar intradiscal pressure: An in vitro study using entire thoracolumbar spine and rib cage specimens

Minimally Invasive Surgery for Posterior Spinal Instrumentation and Fusion in Adolescent Idiopathic Scoliosis: Current Status and Future Application.

The posterior minimally invasive spine surgery (MISS) approach-or the paraspinal muscle approach-for posterior spinal fusion and segmental instrumentation in adolescent idiopathic scoliosis (AIS) was first reported in 2011. It is less invasive than the traditionally used open posterior midline approach, which is associated with significant morbidity, including denervation of the paraspinal muscles, significant blood loss, and a large midline skin incision. The literature suggests that the MISS approach, though technically challenging and with a longer operative time, provides similar levels of deformity correction, lower intraoperative blood loss, shorter hospital stays, better pain outcomes, and a faster return to sports than the open posterior midline approach. Correction maintenance and fusion rates also seem to be equivalent for both approaches. This narrative review presents the results of relevant publications reporting on spinal segmental instrumentation using pedicle screws and posterior spinal fusion as part of an MISS approach. It then compares them with the results of the traditional open posterior midline approach for treating AIS. It specifically examines perioperative morbidity and radiological and clinical outcomes with a minimal follow-up length of 2 years (range 2-9 years).

Safety and efficacy of growth-friendly instrumentation for early-onset scoliosis in patients with spinal muscular atrophy type 1 in the disease-modifying treatment era.

To evaluate the safety of growth-friendly instrumentation for early-onset scoliosis (EOS) in patients with spinal muscular atrophy (SMA) type 1 who received disease-modifying treatment (DMT) and analyze short-term efficacy. Retrospective search was conducted between 2017 and 2023. Patients with genetically confirmed SMA type 1 who were surgically treated for spinal deformity and receiving DMTs (nusinersen, risdiplam, or onasemnogene abeparvovec) were included. SMA types 2 and 3 and patients who do not receive DMTs were excluded. Clinical and radiographic data were collected at preoperative, postoperative, and latest follow-up visits. Twenty-eight patients (mean follow-up: 16 months (range 2-41)) were included. The mean age at surgery was 60 months (range 29-96). Fifteen were treated with dual magnetically controlled growing rods (MCGR), four with unilateral MCGR and a contralateral guided growth system, three with Vertical Expandable Prosthetic Titanium Rib (VEPTR®) implants, five with self-distracting systems, and one with traditional dual growing rods. The mean amount of correction was 57% (44°± 17) for scoliosis and 83% (13°± 11) for pelvic obliquity. The mean T1-12 height gain during surgery was 31 mm (±16 mm), while the mean T1 S1 height gain was 51 mm (±24 mm), and instrumented growth was observed during follow-up. Five patients (18%) developed six serious adverse events: three surgical site infections, two anchor failures, and one rod fracture, and all required unplanned reoperations. No neurologic complication, difficulty during nusinersen injections, or respiratory decline was recorded. We report that spinal deformity in this population can be safely treated with growth-friendly instrumentation, with similar complication rates when compared with SMA type 2.

Gender-Related Factors Influence the Subjective Perception of Deformity in Patients Undergoing Surgery for Idiopathic Scoliosis.

The present study aims to depict the importance of gender-related factors in the subjective perception of spine deformity in adolescents undergoing posterior instrumented fusion for scoliosis. Patients undergoing posterior spinal instrumentation and fusion (PSF) for idiopathic adolescent scoliosis (AIS) were recruited. The following data were recorded: gender, age, parents' civil status, Tegner Activity Scale (TAS), body mass index (BMI), concomitant diseases, and history of neuropsychological disorders. Each patient underwent clinical and radiological evaluations according to the protocol used at our institution. All the patients were assessed before surgery using the following Patient-Reported Outcome Measures (PROMs): the Italian version of the revised Scoliosis Research Society-22 patient questionnaire (SRS-22R), the Quality-of-Life Profile for Spinal Deformities (QLPSDs) questionnaire, and the Spinal Appearance Questionnaire (SAQ). The present study recruited 80 patients (male: 19, female: 61). A significant correlation was observed between BMI, TAS, and subjective perception scores. A worse deformity perception was observed in female patients and patients with divorced parents. Gender-related factors impact the subjective perception of spine deformity in patients undergoing PSF for AIS. Specific assessment and correction are needed to improve postoperative outcomes in these patients.

Intraoperative Radiation Exposure in Adolescent Idiopathic and Neuromuscular Scoliosis.

Intraoperative imaging is often used to aid pedicle screw placement during scoliosis operations. Higher rates of cancer and death have been observed in orthopaedic surgeons and radiation technologists, including a fourfold higher rate of breast cancer in female orthopaedic surgeons. The purpose of this study was to evaluate variability in intraoperative radiation during spinal fusions for both adolescent idiopathic scoliosis (AIS) and neuromuscular scoliosis (NMS). A retrospective review of posterior spinal fusion and segmental spinal instrumentation for scoliosis performed by pediatric orthopaedic surgeons from 2017 to 2019 at a single institution was performed. Inclusion criteria included: a diagnosis of AIS or NMS and patients between 8 and 18 years of age. Exclusion criteria included: revision surgery, use of intraoperative navigation, and patients younger than 10 at the time of scoliosis onset within the AIS cohort. Data collected included: preoperative curve, body mass index (BMI), number of levels fused, number of Ponte osteotomies, and fluoroscopy time. One-way analysis of variance tests, Bonferroni post hoc tests, independent t tests, and Pearson correlations were utilized with significance determined at the 95% confidence level (a = 0.05). A total of 148 patients were included in the study. The average fluoroscopy time was 143 ± 67 seconds. Patients with NMS had higher average fluoroscopy times (193 ± 75 s) compared with patients with AIS (129 ± 58 s, P < 0.001). In patients with AIS, fluoroscopy time correlated to the patient's preoperative curve (r = 0.182, P = 0.050). Patients with AIS with fewer than 12 levels fused had significantly less radiation exposure than those with 12 or more levels fused (P = 0.01). When controlling for the number of levels fused, patients with AIS with higher BMIs had significantly greater fluoroscopy times (P = 0.001). In patients with NMS, fluoroscopy time negatively correlated with BMI (r = -0.459, P = 0.009) and positively correlated with a preoperative curve (r = 0.475, P = 0.007). Fluoroscopy times vary greatly during adolescent spinal fusions for scoliosis. Longer fluoroscopy times are correlated with: NMS diagnosis, larger preoperative curve, BMI, and number of levels fused. Surgeons' knowledge of factors affecting fluoroscopy time will increase awareness and may be the first step in decreasing intraoperative radiation risks. Level III; Therapeutic-a retrospective study.

Growth-preserving instrumentation for early onset scoliosis

Early onset scoliosis is defined as aspinal deformity originating in the first 10years of life. Growth-preserving spinal instrumentation has therefore been designed to preserve growth of spine and chest wall and lungs to avoid serious pulmonary complications after early spine fusion. Indications, surgical technique and results of the vertical expandable prosthetic titanium rib (VEPTR) technique, traditional growing rods (TGR), and magnetically controlled growing rods (MCGR) will be described. Indications for VEPTR are so-called mixed congenital deformities (type3) associated with vertebral malformations in association with chest wall deformities, especially fused ribs. There are also indications for neuromuscular or syndromic early onset scoliosis with bilateral rib-to-ilium constructs. However, most of those deformities are currently treated with either GR or MCGR in most centers. GR and MCGR are currently the treatment of choice for the majority of early onset scoliosis. There is no indication for growth-preserving strategies if the patients are mature or there is only little growth remaining. In these cases, final fusion should be performed. While the VEPTR technique involves an extensive approach with muscular dissections to the thoracic cage including rib osteotomies and thoracotomies, treatment with TGR or MCGR is minimally invasive, only exposing proximal and distal anchor points, leaving most of the spine including the apex undisturbed. Early mobilization is usually possible after 24-48 h. Braces may have to be prescribed for patients with osteopenia, noncompliance, or arisk to fall. Since 2005, more than 200patients were treated with the VEPTR technique, more than 200 patients with the MCGR technique, and about 30patients with the TGR technique in our department. Complication rates are high with all techniques including the law of diminishing returns, autofusion, bone anchor-related complications like loosening or migration of implants, failure to distract and proximal junctional kyphosis. In our own series of 13patients below age 3years, VEPTR proved to be effective for mixed deformities. In other studies, we were able to show that physiological growth with MCGR can be maintained for 2-3years but spinal growth declines after that period with acceptable complications. Complication rates in most studies are lower with MCGR compared to TGR and VEPTR. Therefore, it is currently the treatment of choice for most early onset scoliosis patients.

Do Children With Medicaid Insurance Have Increased Revision Rates 5 Years After Posterior Spinal Fusions?

Socioeconomic disparities in musculoskeletal care are increasingly recognized, however, no studies to date have investigated the role of the insurance carrier on outcomes after posterior spinal fusion (PSF) with segmental spinal instrumentation for adolescent idiopathic scoliosis (AIS). A US insurance dataset was queried using the PearlDiver Mariner software for all patients aged 10 to 18 undergoing PSF for a primary diagnosis of AIS between 2010 and 2020. Age, sex, geographic region, number of levels fused, and baseline medical comorbidities were queried. Complications occurring within 90 days of the index surgery were queried using the International Classification of Diseases, Ninth Revision (ICD-9) and International Classification of Diseases, 10th Revision (ICD-10) codes. Revision surgery was also queried up to 5 years after the index PSF. Categorical variables were compared using the Fisher χ 2 tests and continuous variables were compared using independent t tests. All-cause revision within 5 years was compared using the Kaplan-Meier analysis and a log-rank test. Significance was set at P -value <0.05. A total of 10,794 patients were identified with 9006 (83.4%) patients with private insurance and 1788 (16.6%) patients insured by Medicaid. The mean follow-up in the database was 5.36±3 years for patients with private insurance and 4.78±2.9 years for patients with Medicaid insurance ( P <0.001). Children with AIS and Medicaid insurance had a significantly higher prevalence of asthma, hypertension, and obesity. A larger percentage of children with Medicaid insurance (41.3%) underwent a ≥13-level PSF compared with privately insured children (34.5%) ( P <0.001). Medicaid patients did not experience higher odds of postoperative complications; in addition, revision surgeries occurred in 1.1% and 1.8% of patients with private insurance and Medicaid insurance, respectively at 5 years postoperatively ( P =0.223). Despite worse baseline comorbidities and longer fusion constructs, AIS patients insured with Medicaid did not have higher rates of complications or revisions at 5-year follow-up versus privately insured patients. Level III-retrospective cohort study.

Repeat surgical interventions following "definitive" instrumentation and fusion for idiopathic scoliosis: a 30-year update.

Although spinal fusion (SF) is considered "definitive" treatment in juvenile/adolescent idiopathic scoliosis (JIS/AIS), complications requiring reoperation continue to occur. The purpose of this study was to characterize the evolving rates of reoperation following SF in JIS/AIS. Single-center retrospective review of patients who underwent SF for JIS/AIS as their index surgical treatment between 2013 and 2019. Patient data were collected to identify complications requiring reoperation and factors associated with reoperation. Complication rates from 2013 to 2019 were compared to patients from 1988 to 2012 at the same institution. This study analyzed 934 patients (81.7% female, mean age at surgery 14.5 ± 2.1). Thirty-eight patients (4.1%) required a total of 47 reoperations, a > 50% decrease in overall complication rate from the 2008-2012 population (4.1% vs 9.6%, respectively, p < 0.001). The decrease stemmed mainly from decreases in rates of infection (1.1% vs 4.1%, p < 0.001) and symptomatic implants (0.4% vs 2.1%, p = 0.004). There were, however, non-significant increases in implant failures (0.6% vs 0.2%, p = 0.4367) and pseudoarthrosis (1.0% vs 0.4%, p = 0.5202). Both of these complications were associated with patients with a higher mean weight (implant failure: 70.4kg ± 21.1 vs 56.1kg ± 14.9, p = 0.002; pseudoarthrosis: 85.8kg ± 27.9 vs 55.9 ± 14.5, p = 0.001). Reoperation following SF for JIS/AIS has decreased over the past 7 years when compared to 25years of historical controls. The changing landscape of reoperation demands further research into the risk factors forthose reoperations that have become more common.

Biomechanical Computational Study of Pedicle Screw Position and Density in Adolescent Idiopathic Scoliosis Instrumentation.

Computer simulation of adolescent idiopathic scoliosis instrumentation. To test the hypothesis that different screw densities would result in different apical vertebral rotation (AVR) corrections and bone-screw forces in adolescent idiopathic scoliosis instrumentation. The "Minimize Implants Maximize Outcomes" Clinical Trial revealed that the use of more versus fewer screws resulted in similar coronal plane correction for Lenke 1A curves. However, the biomechanical impact of screw density on transverse plane correction is still unclear. Further investigation is needed to determine if and how transverse plane correction is correlated with screw density. We simulated apical vertebral derotation after segmental translation using patient-specific computer models of 30 patients from the "Minimize Implants Maximize Outcomes" Trial. For each case, 10 alternative screw patterns were tested with overall densities ranging between 1.2 and 2 screws per level fused, and local density at the 3 apical levels ranging between 0.7 and 2 (total: 600 simulations). Main thoracic (MT) Cobb angle, thoracic kyphosis (TK), AVR, and bone-screw forces were computed and compared. The presenting MT (62 ± 11°; range: 45° to 86°), TK (27 ± 20°; -5° to 81°), and AVR (14±7°; -2° to 25°) were corrected through segmental translation to 22 ± 7° (10° to 41°), 26 ± 5° (18° to 45°), and 14 ± 7° (-4° to 26°). After apical vertebral derotation, they became 16 ± 8° (1° to 41°), 24 ± 4° (13° to 40°), and 4 ± 5° (-12° to 18°). There was no significant difference in MT among screw patterns; higher screw density had lower bone-screw forces ( P < 0.05). The apical vertebral derotation maneuver reduced AVR by an average of 70%, positively correlated with apical screw density ( r = 0.825, P < 0.05). There was no significant difference in TK. Screw density had no significant effect on 3-dimensional correction through the primary segmental translation maneuver. Transverse plane correction through subsequent apical vertebral derotation was positively correlated with screw density at the apical levels ( r = 0.825, P < 0.05). Bone-screw forces were negatively correlated with overall screw density ( P < 0.05).

Back Pain and Quality of Life 10 Years After Segmental Pedicle Screw Instrumentation for Adolescent Idiopathic Scoliosis.

Comparative cohort study. The aim of the present study was to evaluate pain and health-related quality of life (HRQoL) in surgically managed patients with a minimum follow-up of 10 years compared with patients with untreated adolescent idiopathic scoliosis (AIS) and a healthy control group. Posterior spinal fusion with pedicle screws is the standard treatment for AIS, although it remains unclear whether this procedure results in improved long-term HRQoL compared with untreated patients with AIS. Sixty-four consecutive patients at a minimum follow-up of 10 years, who underwent posterior pedicle screw instrumentation for AIS were prospectively enrolled. Fifty-three (83%) of these patients completed Scoliosis Research Society (SRS) 24 questionnaires, clinical examination, and standing spinal radiographs. Pain and HRQoL were compared with age and sex-matched patients with untreated AIS and healthy individuals. The mean major curve was 57° preoperatively and 15° at the 10-year follow-up. SRS-24 self-image domain score showed a significant improvement from preoperative to 2 years and remained significantly better at the 10-year follow-up ( P < 0.001). Patients fused to L3 or below had lower pain, satisfaction, and total score than patients fused to L2 or above ( P < 0.05), but self-image, function, and activity scores did not differ between groups at 10-year follow-up. Pain, self-image, general activity, and total SRS domains were significantly better at 10-year follow-up in the surgically treated patients as compared with untreated patients (all P < 0.05). Healthy controls had significantly higher total score s than those surgically treated at 10-year follow-ups ( P < 0.001). Patients undergoing segmental pedicle screw instrumentation for AIS maintain high-level HRQoL during a 10-year follow-up. Their HRQoL was significantly better than in the untreated patients with AIS, except for the function domain. However, HRQoL remained at a lower level than in healthy controls.

Anterior vertebral body tethering for adolescent idiopathic scoliosis associated with less early post-operative pain and shorter recovery compared with fusion

PurposeWhile posterior spinal instrumentation and fusion (PSIF) for severe adolescent idiopathic scoliosis (AIS) is the gold standard, anterior vertebral body tethering (AVBT) is becoming an alternative for select cases. Several studies have compared technical outcomes for these two procedures, but no studies have compared post-operative pain and recovery.MethodsIn this prospective cohort, we evaluated patients who underwent AVBT or PSIF for AIS for a period of 6 weeks after operation. Pre-operative curve data were obtained from the medical record. Post-operative pain and recovery were evaluated with pain scores, pain confidence scores, PROMIS scores for pain behavior, interference, and mobility, and functional milestones of opiate use, independence in activities of daily living (ADLs), and sleeping.ResultsThe cohort included 9 patients who underwent AVBT and 22 who underwent PSIF, with a mean age of 13.7 years, 90% girls, and 77.4% white. The AVBT patients were younger (p = 0.03) and had fewer instrumented levels (p = 0.03). Results were significant for decreased pain scores at 2 and 6 weeks after operation (p = 0.004, and 0.030), decreased PROMIS pain behavior at all time points (p = 0.024, 0.049, and 0.001), decreased pain interference at 2 and 6 weeks post-operative (p = 0.012 and 0.009), increased PROMIS mobility scores at all time points (p = 0.036, 0.038, and 0.018), and faster time to functional milestones of weaning opiates, independence in ADLs, and sleep (p = 0.024, 0.049, and 0.001).ConclusionIn this prospective cohort study, the early recovery period following AVBT for AIS is characterized by less pain, increased mobility, and faster recovery of functional milestones, compared with PSIF.Level of evidenceIV.