Investigating pelvic drop gait abnormality in adolescent hip pathology patients.

BACKGROUND: Trendelenburg gait describes contralateral pelvic drop during single leg stance (SLS) with occasional lateral trunk lean compensation over the stance limb. However, quantitative research on 'uncompensated Trendelenburg' gait (pelvic drop independent of lateral trunk lean) remains sparse among populations that commonly utilize this gait pattern, such as adolescent hip pathology patients. RESEARCH QUESTION: How prevalent is uncompensated Trendelenburg among various adolescent hip pathologies and how is it related to hip load, hip abduction strength, and self-reported hip pain? METHODS: Gait, strength, and pain data were collected among 152 pre-operative patients clinically diagnosed with acetabular hip dysplasia, femoroacetabular impingement, Legg-Calvé-Perthes, or slipped capital femoral epiphysis (SCFE). Patients with ≥ 5.4° of dynamic pelvic drop in SLS were divided into a 'pelvic drop' group and screened to exclude those with excessive ipsilateral trunk lean. They were then compared to the 'stable pelvis' patients using a Mann-Whitney test. RESULTS: Dysplasia patients represented the highest proportion of the pelvic drop group (46%). The pelvic drop group showed a significant increase in self-reported hip pain (p = 0.011), maximum hip abductor moment (p = 0.002), and peak coronal power absorption at the affected hip during SLS loading response, (p < 0.001) while showing no difference in abduction strength (p = 0.381). SIGNIFICANCE: Uncompensated Trendelenburg gait may lead to increased loading of the affected hip in adolescent hip pathology patients. Disadvantageous hip biomechanics can create increased abductor muscle demand among these pathological populations, with dysplasia patients showing the highest prevalence. Maximal abduction strength did not correlate with pelvic drop. Future work should aim to identify and quantify causal factors. Increased coronal hip power absorption during weight acceptance warrants clinical attention, as there may be a detrimental, over-reliance on passive hip structures to support load among a population that that is already predisposed to hip osteoarthritis.

Who gets staged surgery in severe pediatric and adolescent spine deformity?

BACKGROUND: There is significant debate regarding the indications of staged surgery for severe adolescent spinal deformity, and the factors associated with the decision to perform staged compared to same-day surgery have not been previously investigated. Thus, the purpose of this study was to determine which factors were most strongly associated with this decision. METHODS: A prospective multicenter registry of adolescent patients with severe spinal deformity was reviewed. Two cohorts were identified: those who underwent a planned staged surgical procedure for deformity correction and those who underwent a same-day procedure. Patients who underwent an unplanned staged procedure secondary to complications during the initial procedure were excluded. Comparisons were made between these cohorts with respect to preoperative patient and radiographic variables to determine which factors were associated with the decision to perform a staged procedure. Surgical data was also compared to evaluate for differences in the intraoperative management of staged versus same-day patients. RESULTS: Two hundred and twenty-nine patients with severe spinal deformities were identified. Forty patients (17%) underwent a planned staged procedure and 189 patients (80%) underwent a same-day procedure. On univariate analysis of preoperative variables, patients who underwent staged surgery had a significantly younger age at surgery, greater major curve magnitude, greater major curve AVT to CSVL, lesser thoracic spine height, greater radiographic trunk shift, and a greater proportion of patients undergoing revision surgery (as opposed to primary correction) compared to those who underwent a planned single-stage procedure. Multivariate logistic regression of pre-operative variables showed that age < 16 years, maximum cobb angle ≥ 120 degrees, major curve AVT to CSVL of ≥ 3.5 cm, and revision surgery were independently associated with the decision to perform a staged procedure. Intraoperatively, patients in the staged cohort more frequently underwent combined anterior and posterior procedures, grade 4 or higher Schwab osteotomies, and had a greater number of levels fused. CONCLUSION: There is substantial variability with respect to the decision to perform surgery for severe adolescent spine deformities in a staged versus same-day fashion. This large analysis of prospectively collected data is the first to describe the factors most strongly associated with the decision to perform a staged procedure and may help guide the surgical decision-making for these patients.

The Effect of Implant Density on Adolescent Idiopathic Scoliosis Fusion: Results of the Minimize Implants Maximize Outcomes Randomized Clinical Trial.

BACKGROUND: Severe adolescent idiopathic scoliosis (AIS) can be treated with instrumented fusion, but the number of anchors needed for optimal correction is controversial. METHODS: We conducted a multicenter, randomized study that included patients undergoing spinal fusion for single thoracic curves between 45° and 65°, the most common form of operatively treated AIS. Of the 211 patients randomized, 108 were assigned to a high-density screw pattern and 103, to a low-density screw pattern. Surgeons were instructed to use ≥1.8 implants per spinal level fused for patients in the high-implant-density group or ≤1.4 implants per spinal level fused for patients in the low-implant-density group. The primary outcome measure was the percent correction of the coronal curve at the 2-year follow-up. The power analysis for this trial required 174 patients to show equivalence, defined as a 95% confidence interval (CI) within a ±10% correction margin with a probability of 90%. RESULTS: In the intention-to-treat analysis, the mean percent correction of the coronal curve was equivalent between the high-density and low-density groups at the 2-year follow-up (67.6% versus 65.7%; difference, -1.9% [95% CI: -6.1%, 2.2%]). In the per-protocol cohorts, the mean percent correction of the coronal curve was also equivalent between the 2 groups at the 2-year follow-up (65.0% versus 66.1%; difference, 1.1% [95% CI: -3.0%, 5.2%]). A total of 6 patients in the low-density group and 5 patients in the high-density group required reoperation (p = 1.0). CONCLUSIONS: In the setting of spinal fusion for primary thoracic AIS curves between 45° and 65°, the percent coronal curve correction obtained with use of a low-implant-density construct and that obtained with use of a high-implant-density construct were equivalent. LEVEL OF EVIDENCE: Therapeutic Level I . See Instructions for Authors for a complete description of levels of evidence.

A novel uniplanar clamp-hinge correction system for vertebral column resection of severe angular kyphosis: an experimental study using a sawbone model.

PURPOSE: To introduce a novel uniplanar clamp-hinge (Uni-CH) correction system designed for vertebral column resection (VCR) of severe angular kyphosis and test its efficacy using a sawbone simulating model. METHODS: The Uni-CH was introduced and its functionality was demonstrated on a sawbone model simulating severe angular kyphosis. An 83° thoracolumbar angular kyphosis with the apex at T11 was simulated in the sawbone spine model. The deformity was then corrected using the Uni-CH to identify the optimal hinge position for VCR reduction of severe angular kyphosis. RESULTS: The thoracolumbar angular kyphosis, initially measuring a mean of 82.7 ± 0.5°, was corrected to 0°, achieving a 100% correction rate. The optimal hinge position was identified to be at the level of the posterior vertebral body wall (PVBW), which allowed for the maintenance of the spinal cord with a slight shortening of 3%. In contrast, hinge positions located more posteriorly to the PVBW resulted in a greater 42% lengthening of the spinal cord, while positions located more anteriorly led to a greater 27% shortening of the spinal cord. CONCLUSIONS: The Uni-CH proves its efficacy in providing consistent stability to the spinal segments and acts as an adjustable and controllable hinge for VCR correction of severe angular kyphosis in the sawbone model. Placing the hinge pivot at the level of the PVBW preserves the spinal cord, preventing excessive shortening or lengthening during VCR reduction of severe angular kyphosis.

Intraoperative neuromonitoring predicts postoperative deficits in severe pediatric spinal deformity patients.

PURPOSE: To evaluate intraoperative monitoring (IOM) alerts and neurologic deficits during severe pediatric spinal deformity surgery. METHODS: Patients with a minimum Cobb angle of 100° in any plane or a scheduled vertebral column resection (VCR) with minimum 2-year follow-up were prospectively evaluated (n = 243). Preoperative, immediate postoperative, and 2-year postoperative neurologic status were reported. Radiographic data included preoperative and 2-year postoperative coronal and sagittal Cobb angles and deformity angular ratios (DAR). IOM alert type and triggering event were recorded. SRS-22r scores were collected preoperatively and 2-years postoperatively. RESULTS: IOM alerts occurred in 37% of procedures with three-column osteotomy (n = 36) and correction maneuver (n = 32) as most common triggering events. Patients with IOM alerts had greater maximum kyphosis (101.4° vs. 87.5°) and sagittal DAR (16.8 vs. 12.7) (p < 0.01). Multivariate regression demonstrated that sagittal DAR independently predicted IOM alerts (OR 1.05, 95% CI 1.02-1.08) with moderate sensitivity (60.2%) and specificity (64.8%) using a threshold value of 14.3 (p < 0.01). IOM alerts occurred more frequently in procedures with new postoperative neurologic deficits (17/24), and alerts with both SSEP and TCeMEP signals were associated with new postoperative deficits (p < 0.01). Most patients with new deficits experienced resolution at 2 years (16/20) and had equivalent postoperative SRS-22r scores. However, patients with persistent deficits had worse SRS-22r total score (3.8 vs. 4.2), self-image subscore (3.5 vs. 4.1), and function subscore (3.8 vs. 4.3) (p ≤ 0.04). CONCLUSION: Multimodal IOM alerts are associated with sagittal kyphosis, and predict postoperative neurologic deficits. Most patients with new deficits experience resolution of their symptoms and have equivalent 2-year outcomes. LEVEL OF EVIDENCE: II.

Postoperative CT imaging to characterize fusion in pediatric and adolescent vertebral column resection.

BACKGROUND: Vertebral column resection (VCR) is a powerful corrective technique for the management severe, rigid spinal deformities but does carry a relatively high complications rate. One of the feared complications is pseudarthrosis which places the patient at risk for implant failure. We present a single-center experience with post-operative computed tomography (CT) imaging at the osteotomy site to screen for impending pseudarthrosis. METHODS: A retrospective review of a single surgeon series of posterior-only VCR performed for severe pediatric and adolescent spinal deformities was performed. Demographic, radiographic, and clinical data were collected. Patients underwent postoperative CT imaging at the osteotomy site 6-9 months following VCR with grading of the osteotomy fusion. Patients with impending pseudarthrosis were recommended for prophylactic revision surgery. RESULTS: Thirty-three patients were included (mean age 11.6 ± 4.9 years, 54.5% female), undergoing a mean 1.9 level VCR. Kyphoscoliosis accounted for 75.7% (N = 25/33) of cases with 45.5% of all cases being congenital etiology and 60.6% having at least 1 previous surgery. Postoperative CT imaging was performed in 22 patients at a mean of 7.8 months following VCR. Two patients were identified as having impending pseudarthrosis with one undergoing revision surgery to enhance the posterior fusion, with addition of a third rod while one patient refusing surgery who subsequently developed broken hardware requiring revision surgery. No patient with a stable fusion on CT imaging developed a clinically significant pseudarthrosis. DISCUSSION: Postoperative CT imaging of the osteotomy is useful in screening for impending pseudarthrosis and can aide in decision making for clearance to return to activity or the need for prophylactic intervention following VCR in pediatric and adolescent patients. We advocate that obtaining routine CT imaging of the osteotomy site at 6-9 months may identify potential complications earlier and allow for prophylactic intervention.

Does Screening Ultrasound Timing in Developmental Dysplasia of the Hip Need to be Adjusted for Moderate Preterm and Near-term Infants: A Prospective Study.

INTRODUCTION: An initial screening ultrasound is essential for patients at higher risk of developmental dysplasia of the hip (DDH) due to breech presentation or a family history of DDH. The American Academy of Pediatrics recommends screening ultrasounds to be performed after 6 weeks of age to reduce the rate of false positives. However, there is limited evidence regarding whether these screening ultrasounds need to be adjusted for gestational age in prematurity. The purpose of this study was to evaluate the influence of moderate preterm and near-term births on screening hip ultrasounds for high-risk DDH populations. METHODS: We identified all prospectively enrolled patients in a single-center database referred for screening hip ultrasound for DDH. We included those hips referred for risk factors of DDH, including breech presentation, family history of DDH, or hip click, and excluded those with known dysplasia or referral for hip instability. Each ultrasound was measured by a pediatric radiologist to determine the alpha angle and femoral head coverage. Patients were classified as "premature" if born at <37 weeks gestation or "full term" if born at ≥37 weeks gestation. All patients underwent screening hip ultrasound between 5 and 8 weeks of age. Sonographic markers of dysplasia and the incidences of abnormal ultrasound and Pavlik harness treatment were compared between cohorts. Significance was set at P <0.05. RESULTS: A total of 244 hips in 122 patients were included, 58 hips in the premature cohort and 186 hips in the full-term cohort. The premature cohort had a significantly decreased gestational age compared with the full-term cohort (35.4 ± 1.1 vs 38.5 ± 1.1 wk, respectively, P < 0.001). However, there was no difference between premature and full-term cohorts in sex distribution (69% vs 75%, females, P = 0.39), unadjusted age at the time of ultrasound (6.6 ± 0.7 vs 6.8±0.7 wk, respectively, P = 0.07), or referral reason ( P = 0.14). On hip ultrasound, there was no difference between premature and full-term cohorts with respect to alpha angle (62.6 ± 3.3 vs 62.2 ± 5.3 degrees, P = 0.41), femoral head coverage (54.9 ± 6.3 vs 55.1 ± 10.6, P = 0.19), rate of abnormal ultrasound (18.3% vs 20.7%, respectively, P = 0.68), or the rate of Pavlik harness treatment (0% vs 5.3%, respectively, P = 0.12). DISCUSSION: There was no significant difference in alpha angle or femoral head coverage between premature and full-term patients at 5 to 8 weeks of unadjusted age. This preliminary data suggests that screening ultrasounds can be performed without adjusting for prematurity. LEVEL OF EVIDENCE: Level II, prognostic study.

Comparison of Gait and Functional Outcomes Between Open and Arthroscopic Treatment of Adolescent and Young Adult Femoroacetabular Impingement.

BACKGROUND: Management of femoroacetabular impingement (FAI) through an arthroscopic or surgical hip dislocation (SHD) approach has been shown to have similar clinical success and patient-reported outcomes. However, there are limited data comparing functional outcomes. The purpose of this study was to compare gait and functional outcomes of adolescent/young adult patients with FAI treated by either an arthroscopic or open SHD approach. METHODS: We identified prospectively enrolled adolescent/young adult patients (≤20 years old) who underwent surgical treatment for FAI through an SHD or arthroscopic approach. Participants were evaluated in a movement science lab preoperatively and postoperatively (minimum 8 months postoperatively) with barefoot walking and a 30-second single-limb balance trial on the affected side. Participants also completed the Harris Hip Score at the same timepoints. Differences from preoperative to postoperative were determined using a paired-samples t test for each surgical technique, and differences between the SHD and arthroscopic groups were determined using an independent samples t test (α=0.05). RESULTS: Fifty-five participants (42F, 16.2±1.4 y) were tested and grouped by surgical intervention. The SHD and arthroscopy groups consisted of 28 and 27 participants, respectively, with no significant difference between the SHD and arthroscopic cohorts in age (16.4±1.2 vs. 15.9±1.5 y, respectively, P =0.218) or sex distribution (78.6% vs. 74.1% females, respectively, P =0.75). Each group demonstrated significant postoperative improvement in Harris Hip Score (SHD: 64.8±16.4 to 81.8±17.8; arthroscopy: 57.0±16.7 to 84.7±19.7; preoperatively to postoperatively, respectively, both P <0.001). During gait, increased maximum hip flexion was observed following surgical intervention for the SHD group (32.3±5.7 vs. 36.1±5.2, P =0.003). No other clinically significant changes were detected in the SHD or arthroscopic groups preoperatively to postoperatively in trunk, pelvis, or hip kinematics in the coronal plane. During the balance task, neither cohort demonstrated markers of clinically significant abductor dysfunction. However, post operatively, the arthroscopy group was able to balance longer than the SHD group (18.8±7.8 vs. 14.2±2.7 s, respectively, P =0.008), although no differences were detected in trunk or pelvis position in the coronal plane during balance. CONCLUSIONS: Both open SHD and arthroscopic treatment of FAI resulted in improved clinical outcomes with no clinically significant abductor dysfunction 1 year post operatively. However, further study is needed to determine whether more dynamic tasks can potentially elicit subtle differences between the groups. LEVELS OF EVIDENCE: Level II-prospective study.

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

BACKGROUND: 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). METHODS: 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. RESULTS: 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). CONCLUSION: 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 OF EVIDENCE: Level III-retrospective cohort study.

An Analysis of Scoliosis in Autism Spectrum Disorder.

BACKGROUND: Children with autism/Asperger are grouped into the diagnosis of autism spectrum disorder (ASD). It remains uncertain whether children with ASD and scoliosis have radiographic and clinical outcomes similar to idiopathic scoliosis (IS) patients. METHODS: A single-center, retrospective review of a prospective scoliosis registry evaluated patients who had a posterior spinal fusion±Anterior Spinal Fusion and an underlying diagnosis of ASD between 1990 and 2021. A 2:1 match with AIS patients by age and sex was compared using demographic, radiographic, intraoperative, and SRS-22/30 variables. RESULTS: Thirty patients with ASD (63% male, mean age at surgery 14.6±2.5 y) met inclusion criteria, with a follow-up of 2.46±1.00 years. Despite no differences in curve magnitude preoperatively, patients with ASD had a higher percent correction at 2-year follow-up (66% vs. 57%, P =0.01) and improved mean curve magnitude (20±10 degrees) at 2-year follow-up compared with IS patients (27±11 degrees, P <0.01). ASD patients had less lumbar lordosis preoperatively (40±12 vs. 53±14, P <0.01), but there were no significant differences in sagittal parameters at 2-year follow-up. There were no significant differences in the rate of complications at 2-year follow-up between ASD and AIS cohorts. CONCLUSIONS: Although patients with ASD exhibited decreased lordosis compared with IS patients preoperatively, their radiographic outcomes at 2-year follow-up were the same. In addition, ASD patients maintained greater curve correction than IS patients at 2 years follow-up. LEVEL OF EVIDENCE: Prognostic retrospective study.

Early brace treatment for idiopathic scoliosis may change the paradigm to improve curves.

PURPOSE: This study evaluated whether early brace treatment of curves < 25° decreased the prevalence of curve progression and surgery. METHODS: In a retrospective review, patients with idiopathic scoliosis Risser stages 0 to 2 braced at < 25° were followed until brace discontinuation, skeletal maturity, or surgery. Patients with predominantly primary thoracolumbar/lumbar curves were prescribed nighttime braces (NTB) and thoracic curves were prescribed fulltime braces (FTB). Comparisons were made for TLSO type (NTB vs. FTB) and triradiate cartilage (TRC) status (open vs. closed) at brace prescription. RESULTS: 283 patients were included, 81% who were Risser stage 0 with curves averaging 21.8° ± 2.1° at brace prescription. The average curve change was 2.4° ± 11.2°. Curves improved ≥ 6° in 23% of patients. Patients who were not skeletally mature at brace discontinuation (n = 39) had lower Cobb angles (16.7° vs. 23.9°, p < 0.001), better curve improvement (- 4.7° vs. 2.1°, p < 0.001), and were braced for a shorter period of time (1.8 years vs. 2.3 years, p = 0.011) than those who were skeletally mature at brace discontinuation (n = 239). Only 7% of patients in NTB and 8% of patients in FTB with open TRC required surgery. The numbers needed to treat to prevent surgery in patients in FTB with open TRC was calculated to be 4. CONCLUSION: Early brace treatment (Cobb < 25° and open TRC) may not only reduce curve progression and the need for surgical treatment but may also result in curve improvement, thus challenging the paradigm that the goal of bracing is merely to stop curve progression. LEVEL OF EVIDENCE: 3-retrospective cohort study.

The Impact of Age on Clinical Outcomes of Acetabular Microfracture During FAI Surgery.

BACKGROUND: Full-thickness acetabular cartilage lesions are common findings during primary surgical treatment of femoroacetabular impingement (FAI). PURPOSE: To evaluate clinical outcomes after acetabular microfracture performed during FAI surgery in a prospective, multicenter cohort. STUDY DESIGN: Cohort Study; Level of evidence, 3. METHODS: Patients with FAI who had failed nonoperative management were prospectively enrolled in a multicenter cohort. Preoperative and postoperative (mean follow-up, 4.3 years) patient-reported outcome measures were obtained with a follow-up rate of 81.6% (621/761 hips), including 54 patients who underwent acetabular microfracture. Patient characteristics, radiographic parameters, intraoperative disease severity, and operative procedures were analyzed. Propensity matching using linear regression was used to match 54 hips with microfracture to 162 control hips (1:3) to control for confounding variables. Subanalyses of hips ≤35 and >35 years of age with propensity matching were also performed. RESULTS: Patients who underwent acetabular microfracture were more likely to be male (81.8% vs 40.9%; P < .001), be older in age (35.0 vs 29.9 years; P = .001), have a higher body mass index (27.2 vs 25.0; P = .001), and have a greater alpha angle (69.6° vs 62.3°; P < .001) compared with the nonmicrofracture cohort (n = 533). After propensity matching to control for covariates, patients treated with microfracture displayed no differences in the modified Harris Hip Score or Hip Disability and Osteoarthritis Outcome Score (P = .22-.95) but were more likely to undergo total hip arthroplasty (THA) (13% [7/54] compared with 4% [6/162] in the control group; P = .002), and age >35 years was associated with conversion to THA after microfracture. Microfracture performed at or before 35 years of age portended good outcomes with no significant risk of conversion to THA at the most recent follow-up. CONCLUSION: Microfracture of acetabular cartilage defects appears to be safe and associated with reliably improved short- to mid-term results in younger patients; modified expectations should be realized when full-thickness chondral lesions are identified in patients >35 years of age.

Unilateral thoracic spinal nerve resection creates early onset thoracic scoliosis in an immature porcine model.

PURPOSE: To test whether multiple-level unilateral thoracic spinal nerves (TSN) resection can induce the initial thoracic cage deformity to cause early onset thoracic scoliosis in an immature porcine model; and 2) to create an early onset thoracic scoliosis in a large animal model that can be used to evaluate growth-friendly surgical techniques and instruments in growing spine researches. METHODS: Seventeen one-month-old pigs were assigned to 3 groups. In group 1 (n = 6), right TSN were resected from T7 to T14 with the contralateral (left) paraspinal muscle exposing and stripping. In group 2 (n = 5), the animals were treated in the same way except the contralateral (left) side was intact. In group 3 (n = 6), bilateral TSN were resected from T7 to T14. All animals were followed up for 17-weeks. Radiographs were measured and analyzed the correlation between the Cobb angle and thoracic cage deformity. A histological examination of the intercostal muscle (ICM) was performed. RESULTS: In the groups 1 and 2, an average 62 ± 12° and 42 ± 15° right thoracic scoliosis with apical hypokyphosis of a mean - 5.2 ± 16° and - 1.8 ± 9° were created, respectively, during 17-weeks follow up. All curves were located at the operated levels with the convexity toward the TSN resection side. Statistical analysis demonstrated that the thoracic deformities were strongly correlated with the Cobb angle. In group 3, no scoliosis was created in any animal, but an average thoracic lordosis of - 32.3 ± 20.3° was seen. The histological examination showed the ICM denervation on the TSN resection side. CONCLUSION: Unilateral TSN resection induced the initial thoracic deformity toward the TSN resection side resulting in thoracic hypokyphotic scoliosis in an immature pig model. This early onset thoracic scoliosis model could be used to evaluate the growth-friendly surgical techniques and instruments in future growing spine researches.

Perioperative Complications and Health-related Quality of Life Outcomes in Severe Pediatric Spinal Deformity.

STUDY DESIGN: Prospective multicenter cohort study. OBJECTIVE: To evaluate perioperative complications and mid-term outcomes for severe pediatric spinal deformity. SUMMARY OF BACKGROUND DATA: Few studies have evaluated the impact of complications on health-related quality of life (HRQoL) outcomes in severe pediatric spinal deformity. METHODS: Patients from a prospective, multicenter database with severe pediatric spinal deformity (minimum of 100 degree curve in any plane or planned vertebral column resection (VCR)) with a minimum of 2-years follow-up were evaluated (n=231). SRS-22r scores were collected preoperatively and at 2-years postoperatively. Complications were categorized as intraoperative, early postoperative (within 90-days of surgery), major, or minor. Perioperative complication rate was evaluated between patients with and without VCR. Additionally, SRS-22r scores were compared between patients with and without complications. RESULTS: Perioperative complications occurred in 135 (58%) patients, and major complications occurred in 53 (23%) patients. Patients that underwent VCR had a higher incidence of early postoperative complications than patients without VCR (28.9% vs. 16.2%, P =0.02). Complications resolved in 126/135 (93.3%) patients with a mean time to resolution of 91.63 days. Unresolved major complications included motor deficit (n=4), spinal cord deficit (n=1), nerve root deficit (n=1), compartment syndrome (n=1), and motor weakness due to recurrent intradural tumor (n=1). Patients with complications, major complications, or multiple complications had equivalent postoperative SRS-22r scores. Patients with motor deficits had lower postoperative satisfaction subscore (4.32 vs. 4.51, P =0.03), but patients with resolved motor deficits had equivalent postoperative scores in all domains. Patients with unresolved complications had lower postoperative satisfaction subscore (3.94 vs. 4.47, P =0.03) and less postoperative improvement in self-image subscore (0.64 vs. 1.42, P =0.03) as compared to patients with resolved complications. CONCLUSION: Most perioperative complications for severe pediatric spinal deformity resolve within 2-years postoperatively and do not result in adverse HRQoL outcomes. However, patients with unresolved complications have decreased HRQoL outcomes.

A thoracoscopic anterior approach to the spine for adolescent idiopathic scoliosis does not have a detrimental effect on pulmonary function at 2 years compared to posterior-only surgery.

PURPOSE: This study aims to examine pulmonary function outcomes in patients with adolescent idiopathic scoliosis (AIS) undergoing posterior spinal fusion (PSF) with an anterior thoracoscopic release compared to those undergoing PSF alone. METHODS: A retrospective review of patients with AIS over a 9-year period at a single institution compared 2 groups: PSF with video-assisted thoracoscopic surgery (PSF/VATS) and patients undergoing a posterior spinal fusion (PSF) alone. Standard radiographs and Forced Expiratory Volume (FEV1) and Forced Vital Capacity (FVC) were obtained preoperatively and at regular follow up periods up to 2-year post-operatively. Within group and between-group comparisons were performed. RESULTS: There were 110 patients in the study: 12 in the PSF/VATS cohort and 98 in the PSF only cohort. The PSF/VATS group were younger (12.6 vs. 14.6, p = 0.003) and had larger coronal curves (80.8° vs. 60.7°, p = 0.001), and worse preoperative FVC (64.7% vs. 79.6%, p = 0.018) and FEV1 (62.3% vs. 77.6%, p = 0.003). At 2 years, the percent coronal Cobb correction was greater in the PSF/VATS group (67.9% vs. 48.4%, p < 0.001) with greater improvement in thoracic height (32.8 mm vs. 20.7 mm, p = 0.028). While the 2-year PFTs were the same for FEV1% (75.8% vs. 81.8%, p = 0.368) and FVC% (77.3% vs. 83.7%, p = 0.562), there was greater percent improvement over the 2 years in the PSF/VATS cohort: FEV1% (13.5% vs. 4.2%, p = 0.082) and FVC% (12.7% vs. 4.1%, p = 0.112). CONCLUSION: AIS patients who have a VATS approach in addition to PSF have greater coronal plane correction and improved pulmonary function compared to PSF alone despite more severe spinal deformity and worse baseline pulmonary function.

The Significance of Isolated Hip Click as a Sign of DDH: Implications on Referral Guidelines.

BACKGROUND: The clinical significance of an isolated hip click remains unclear. The rates of developmental dysplasia of the hip (DDH) in those referred for hip click vary from 0% to 28%. The purpose of this study was to evaluate the rate of DDH in patients prospectively referred for isolated hip click. METHODS: We prospectively enrolled patients referred to a single pediatric orthopaedic center with concern for DDH secondary to isolated hip click felt by the pediatrician on examination. Patients with known sonographic abnormalities or risk factors for DDH (breech presentation or positive family history) were excluded. Ultrasounds were obtained upon initial presentation and defined as abnormal if alpha angle <60 degrees and/or femoral head coverage (FHC) <50%. Mild dysplasia, analogous to Graf IIa physiological immaturity, was defined as alpha angle 50<α<60 and/or <50% FHC in a patient <3 months age. Severe dysplasia was defined as ≤33% FHC, which has been proposed to be sonographically consistent with a hip dislocation. RESULTS: Two hundred fifty-five children were referred for isolated hip click. One hundred eighty-nine patients (74%) had normal ultrasound whereas 66 patients (26%) had sonographic abnormalities (mean age 6.5±6.2 wk at initial ultrasound). Fifty patients (19.6%) demonstrated physiological immaturity, 3 patients (1.2%) demonstrated moderate sonographic dysplasia, and 13 patients (5.1%) had sonographic findings consistent with severe dysplasia or dislocated hip. Hips with severe dysplasia were younger than the remaining population (2.8±2.4 wk vs. 6.6±6.2 wk, P <0.001) with no difference in sex distribution ( P =0.07) or first-born birth order ( P =0.36). For those with sonographic abnormality, 18 (27%) patients were treated with Pavlik harness, 1 (2%) was treated with abduction orthosis, and the remainder (71%) were observed for resolution of physiological immaturity. CONCLUSIONS: Infants with isolated hip click identified by their pediatrician may have higher rates of dysplasia than previously reported. We recommend screening ultrasound and/or orthopaedic referral for all infants with isolated hip click. LEVEL OF EVIDENCE: Level II-prospective prognostic study.

Surgical treatment of double major adolescent idiopathic scoliosis can lead to excessive lumbar lordosis in the instrumented segments.

PURPOSE: The purpose of this study was to characterize the sagittal spine in AIS patients with double major curves fused into the lumbar spine to determine the effects of posterior spinal fusion and instrumentation (PSFI) on global and segmental lumbar sagittal parameters. METHODS: A consecutive series of AIS patients undergoing a PSFI from 2012 to 2017 having Lenke 3, 4 or 6 curves were analyzed. Sagittal parameters included pelvic incidence (PI), lumbar lordosis (LL), and segmental lordosis were measured. The difference in segmental lumbar lordosis between the preoperative, 6-week, and 2-year radiographs was analyzed and correlated to outcomes using SRS-30 patient questionnaires. RESULTS: Seventy-seven patients had improvement in their coronal Cobb from 67.3 ± 11.8° to 25.43 ± 10.7° (66.4%) at 2 years. There was no change in thoracic kyphosis (23.0 ± 13.4° to 20.3 ± 7.8°) and pelvic incidence (49.9 ± 13.4° to 51.1 ± 15.7°) from preoperative to 2 years (p > 0.05) while lumbar lordosis increased from 57.6 ± 12.4° to 61.4° ± 12.3° (p = 0.002). Segmental lumbar analysis showed increased (+) lordosis at each instrumented level when comparing the preoperative and 2-year films for: T12-L1 (+ 3.24°, p < 0.001), L1-L2 (+ 5.70°, p < 0.001), and L2-L3 (+ 1.70°, p < 0.001). Loss (-) of lordosis was noted at every level below the LIV: L3-L4 (- 1.70°, p < 0.001), L4-L5 (- 3.52°, p < 0.001), L5-S1 (- 1.98°, p = 0.02). Preoperative LL of L4-S1 comprised 70 ± 16% of the global LL compared to 56 ± 12%, at 2 years (p < 0.001). Changes in sagittal measurements did not correlate with SRS outcome scores at two-year follow-up. CONCLUSION: When performing PSFI for double major scoliosis, global SVA was maintained at 2 years, however, overall lumbar lordosis increased due to an increased lordosis in the instrumented segments and a smaller decrease in lordosis below the LIV. Surgeons should be wary of the tendency to create instrumented lumbar lordosis with a compensatory loss of lordosis below LIV which may be a set-up for poor long-term outcomes in adulthood.

A United States multi-site randomized control trial of Schroth-based therapy in adolescents with mild idiopathic scoliosis.

PURPOSE: The purpose of this study was to determine the feasibility and efficacy of a United States multi-site randomized control trial (RCT) of the Schroth-based therapy program in Risser 0 patients with mild adolescent idiopathic scoliosis (AIS) curves. METHODS: Six sites enrolled 98 Risser 0 patients with single AIS curves between 12° and 24°. Patients were randomized to Exercise:Control group in a 2:1 ratio. Exercise group patients were instructed on the Schroth-based method and a home exercise program of 75 min/week for 1 year. RESULTS: Enrollment across 6 institutions averaged 2.2 patients per month over 45 months. Patient attrition was 42% after 1 year (41/98) and 52% after 2 years (51/98). Exercise group patients were significantly younger (11.6 vs 12.5 years) without differences in the baseline Cobb angle (16.2° vs 17.1°). Self-reported exercise adherence averaged 82% at 6 months and 63% at 1 year (n = 35). A significantly lower frequency of patients was braced in the Exercise group after 1 year (26% vs 55%, p = 0.03) but not after 2 years (48% vs 63%, p = 0.31). Curve magnitude changes between groups were not significant after 1 and 2 years. CONCLUSION: Performing a multi-site RCT for mild AIS in the United States is challenging with slow enrollment and high attrition. Young patients with small curves have difficulty adhering to the intensive demands of Schroth-based therapy. LEVEL OF EVIDENCE: II.