Evaluation of Vertebral derotation in the correction of Adolescent Idiopathic Scoliosis

Background Adolescent idiopathic scoliosis (AIS) represents a complex three-dimensional deformity. The rotation of the apical vertebrae is primarily responsible for the rib hump that represents the main cosmetic problem for adolescent patients. Correcting rotational deformity and maintaining the normal sagittal profile of the spine is more important than onlycorrecting coronal deformity. Aim of the Work to evaluate the efficacy of vertebral derotation using Single Concave Rod Rotation (SCRR) maneuver in the treatment of patients with Adolescent Idiopathic Scoliosis (AIS) by clinical and radiological follow up for 1 year. Patients and Methods This prospective analysis was done on 30 patients with AIS, who underwent one stage posterior only corrective surgery with SCRR maneuver between 2016 and 2019 at Ain Shams University Hospitals in order to correct their deformities. All patients included in this study had idiopathic curve between 40 and 80 degrees, with flexibility index < 50%, and their ages were between 10 and skeletal maturity. Results Compared to the results obtained by other studies using the same technique, our study included patients with relatively large curve magnitude and the lowest flexibility index, had average coronal correction rate by about 65.5% and minimal correction loss during follow up (-1°). Furthermore, our study included the largest mean preoperative RA. The axial correction rate was average (32.7%) and has the lowest complication rate and better clinical outcome and patient satisfaction among other studies that used SCRR maneuver. However, the mean operating time in our series in the present study was longer than the mean operating time in the literature. The mean amount of blood loss in our study was more than the mean amount in other studies. Conclusion Simple concave rod rotation is a good option for correction of the deformed curve in AIS. We can state that simple concave rod rotation with pedicle screw instrumentation and without the use of DVD maneuver could successfully correct both coronal and axial deformity with minimal complication. Adding DVD technique offers a better correction of apical vertebra rotation.

The Effect of Brace Treatment on Large Curves of 40° to 55° in Adolescents With Idiopathic Scoliosis Who Have Avoided Surgery: A Retrospective Cohort Study

Objective: To evaluate the effect of Milwaukee brace treatment on adolescents with idiopathic scoliosis (AIS) with large curves (40° to 55°) who refuse to do surgery.Methods: In this retrospective cohort study, we gathered the clinical records of all adolescents with AIS with an initial curve of 40° to 55°. They had been referred to our center from December 1990 to January 2017. Although they had been advised to do surgery, they had all refused to do it. Their clinical data were recorded, such as sex, age, Risser sign, scoliosis, and kyphosis curve magnitude (at the beginning of brace treatment, weaning time, brace discontinuation, and minimum of 2 years after the treatment). Based on treatment success, the patients were divided into 2 groups: progressed and nonprogressed.Results: Sixty patients with an average initial Cobb angle of 44.93° ± 4.86° were included. The curve progressed in 57%, stabilized in 25%, and improved in 18% of the patients. In the progressed group (34 patients), 31 patients had undergone surgery. There was no significant association between the age of beginning the brace treatment and the final Cobb angle of nonprogressed group (p > 0.05). However, in-brace correction and initial Risser sign had a significant correlation with curve magnitude at the final follow-up (p < 0.05).Conclusion: Brace treatment seems to be effective in controlling the further curve progression in AIS with 40° and 55° curves. Our results can help physicians make sound decisions about the patients with larger curves who refuse to do surgery.

Longitudinal scoliosis behavior in Chiari malformation with and without syringomyelia

OBJECTIVE The objective of this study was to understand the natural history of scoliosis in patients with Chiari malformation type I (CM-I) with and without syringomyelia. METHODS A retrospective review of data was conducted. Patients with CM-I were identified from a cohort of 14,118 individuals age 18 years or younger who had undergone MRI over an 11-year period at the University of Michigan. Patients eligible for study inclusion had a coronal curve ≥ 10° on radiography, associated CM-I with or without syringomyelia, and at least 1 year of clinical follow-up prior to any surgery. Curve magnitude at initial diagnosis, prior to posterior fossa decompression (PFD; if applicable), and at the last follow-up (prior to any surgical correction of scoliosis) was recorded, and clinical and radiographic characteristics were noted. The change in curve magnitude by 10° was defined as curve progression (increase by 10°) or regression (decrease by 10°). RESULTS Forty-three patients met the study inclusion criteria and were analyzed. About one-third (35%) of the patients presented with symptoms attributed to their CM-I. The mean degree of scoliosis at presentation was 32.6° ± 17.7°. Twenty-one patients (49%) had an associated syrinx. The mean tonsil position below the level of the foramen magnum was 9.8 ± 5.8 mm. Patients with a syrinx were more likely to have a curve > 20° (86% vs 41%, p = 0.002). Curve magnitude remained stable (≤ ±10°) in 77% of patients (33/43), progressed in 16% (7/43), and regressed in 7% (3/43). Mean age was higher (14.8 ± 0.59 years) among patients with regressed curves (p = 0.026). All regressed curves initially measured ≤ 20° (mean 14° ± 5.3°), and none of the patients with regressed curves had a syrinx. The change in curve magnitude was statistically similar in patients with (7.32° ± 17.7°) and without (5.32° ± 15.8°) a syrinx (p = 0.67). After a mean follow-up of 3.13 ± 2.04 years prior to surgery, 27 patients (63%) ultimately underwent posterior fossa or scoliosis correction surgery. For those who eventually underwent PFD only, the rate of change in curve magnitude prior to surgery was 0.054° ± 0.79°. The rate of change in curve magnitude was statistically similar before (0.054° ± 0.79°) and after (0.042° ± 0.33°) surgery (p = 0.45) for patients who underwent PFD surgery only. CONCLUSIONS The natural history of scoliosis in the presence of CM-I is variable, though most curves remained stable. All curves that regressed were ≤ 20° at initial diagnosis, and most patients in such cases were older at scoliosis diagnosis. Patients who underwent no surgery or PFD only had similar profiles for the change in curve magnitude, which remained relatively stable overall, as compared to patients who underwent PFD and subsequent fusion, who demonstrated curve progression. Among the patients with a syrinx, no curves regressed, most remained stable, and some progressed. Understanding this variability is a first step toward building a prediction model for outcomes for these patients.

Bracing for infantile scoliosis: no sedation needed

Mehta casting technique applied under anesthesia is standard treatment for infantile scoliosis (IIS). However, concern has been raised about frequent anesthesia in children less than three years. The development of a customized thoracolumbar sacral orthosis (TLSO) could avoid the risks of Mehta casting. To develop a bracing technique for IIS that achieves patient compliance and scoliosis correction. Nine patients with ISS were offered a custom TLSO as an alternative to Mehta casting. One patient declined due to an insurance issue. No anesthesia was required for measurement or fitting of the TLSO. A temperature sensitive monitor recorded wear time. Brace success was determined by radiographic correction and adherence to prescription of greater than 18 hours per day. Eight patients had brace treatment with mean(range): age 19(12–44) months, curve magnitude 34° (22–44°), rib vertebral angle of greater than 20° with follow-up 17(3–28) months. In brace correction was less than 15 degrees in 6 of 8 patients. Compliance monitor recorded wear: 4 patients ≥ 18 hours, 2 patients 16–18 hours, 1 had 14 hours, and 1 monitor malfunctioned and could not be read. Brace design evolved to maximize ipsilateral abdominal relief away from the lateral apical shift of the design. Foam lining was added to prevent skin irritation through the relief opening. Average number of braces per year =2.2. A customized TLSO can achieve in brace correction comparable to Mehta casting with acceptable compliance and without the need for general anesthesia, while allowing bathing and skin care.

Extradural decompression versus duraplasty in Chiari malformation type I with syrinx: outcomes on scoliosis from the Park-Reeves Syringomyelia Research Consortium

OBJECTIVE Scoliosis is common in patients with Chiari malformation type I (CM-I)–associated syringomyelia. While it is known that treatment with posterior fossa decompression (PFD) may reduce the progression of scoliosis, it is unknown if decompression with duraplasty is superior to extradural decompression. METHODS A large multicenter retrospective and prospective registry of 1257 pediatric patients with CM-I (tonsils ≥ 5 mm below the foramen magnum) and syrinx (≥ 3 mm in axial width) was reviewed for patients with scoliosis who underwent PFD with or without duraplasty. RESULTS In total, 422 patients who underwent PFD had a clinical diagnosis of scoliosis. Of these patients, 346 underwent duraplasty, 51 received extradural decompression alone, and 25 were excluded because no data were available on the type of PFD. The mean clinical follow-up was 2.6 years. Overall, there was no difference in subsequent occurrence of fusion or proportion of patients with curve progression between those with and those without a duraplasty. However, after controlling for age, sex, preoperative curve magnitude, syrinx length, syrinx width, and holocord syrinx, extradural decompression was associated with curve progression > 10°, but not increased occurrence of fusion. Older age at PFD and larger preoperative curve magnitude were independently associated with subsequent occurrence of fusion. Greater syrinx reduction after PFD of either type was associated with decreased occurrence of fusion. CONCLUSIONS In patients with CM-I, syrinx, and scoliosis undergoing PFD, there was no difference in subsequent occurrence of surgical correction of scoliosis between those receiving a duraplasty and those with an extradural decompression. However, after controlling for preoperative factors including age, syrinx characteristics, and curve magnitude, patients treated with duraplasty were less likely to have curve progression than patients treated with extradural decompression. Further study is needed to evaluate the role of duraplasty in curve stabilization after PFD.

Genetic variant of MIR4300HG is associated with progression of adolescent idiopathic scoliosis in a Chinese population

Background A recent genome-wide association study identified a susceptible locus in MIR4300HG gene that was associated with curve progression of adolescent idiopathic scoliosis (AIS) in the Japanese population. However, the association between the gene and curve progression in other populations remains unclear. Methods A cohort of 1952 AIS patients and 2495 healthy controls were included in the case-control analysis. In the case-only analysis, 747 patients were assigned to the progression group and 520 patients were assigned to the non-progression group, respectively. Rs35333564 was genotyped for all the subjects. Paraspinal muscles of 76 patients were collected for the analysis of gene expression. Chi-square test and ANOVA test were used for the intergroup comparison. Pearson correlation analysis was performed to investigate the relationship between the gene expression and curve magnitude. Results Variant rs35333564 was significantly associated with the curve severity of AIS (p = 0.025), but not the development of AIS (p = 0.418). Genotype GG was indicated by remarkably lower expression of MIR4300 (p = 0.020) which was significantly correlated with curve magnitude (p = 0.010). As a predicted target gene of MIR4300, the expression of CRTC1 was negatively correlated with MIR4300 expression (p = 0.012, r = −0.287) and positively correlated with curve severity (p = 0.025, r = 0.257). Conclusions The association between rs35333564 and curve progression was successfully replicated in a Chinese AIS population. CRTC1 may be the target gene of MIR4300 that plays a role in the curve progression of AIS.

Evaluation of correction rates for titanium-alloy and cobalt-chrome-alloy rods in adolescent idiopathic scoliosis

<p><strong>Background: </strong>The customary treatment of AIS is spinal fusion with instrumentation using rigid rods. In parallel, agents such as, curve magnitude, points of fixation, level instrument selection, curve flexibility, kind of anchor rods used for patients and post-operative care are the main factors affecting the outcome of surgery.</p><p><strong>Methods: </strong>A total 50 patients was included in the study. The control group, which included 31 patients treated with Ti rods, was compared with an experimental group of 19 patients treated with CCM rods. Correction surgery was performed through posterior approach using rod-rotation maneuver after inserting a pedicle screw in each vertebrae within the fusion. Six-millimeter CCM and six-millimeter Ti rods were used in experimental and control groups, respectively. Pre and postoperative indices of coronal alignment and sagittal alignment were measured.</p><p><strong>Results: </strong>There was no statistical difference between the two groups for age, sex, Risser’s stage, preoperative Cobb’s angle, type and flexibility of curvature. The correction rate of thoracic curve was 71.4±10.2% for the CCM group and 71.8±6.1% for the Ti group. There were no statistical differences between the two groups for all coronal and sagittal factors (p&gt;0.05).</p><p><strong>Conclusions: </strong>AIS cases with double curvature, there was no statistically significant difference between Ti and CCM rods for coronal and sagittal plane correction rates. The derivations from biomechanical studies do not translate into clinical situations.</p>

Higher pedicle screw density does not improve curve correction in Lenke 2 adolescent idiopathic scoliosis

Purpose Higher pedicle screw density posterior spinal fusion (PSF) constructs have not been shown to result in improved curve correction in Lenke 1 and 5 adolescent idiopathic scoliosis (AIS) but do increase cost. The purpose of this study questioned whether higher screw density constructs improved curve correction and maintenance of correction in Lenke 2 AIS. Secondary goals were to identify predictive factors for correction and postoperative magnitude of curves in Lenke 2 AIS. Methods We identified patients 11 to 17 years old who underwent primary PSF for Lenke 2 AIS between 2007 and 2017 who had minimum follow-up of 2 years. Demographic and radiographic data were collected to perform regression and elimination analysis. Results Thirty patients (21 females, 9 males) were analyzed. Average age and SD at time of surgery was 14.0 ± 1.8 years (range, 11–17 years), and median follow-up was 2.8 years (IQR 2.1–4.0 years). Implant density did not predict final postoperative curve magnitude. Predictors of final postoperative curve magnitude were sex and preoperative curve magnitude. Predictors of percentage of correction of major curve were sex and age at the time of surgery. Predictors of final postoperative thoracic kyphosis were sex and percent flexibility preop. Females had lower final postoperative major curve magnitude, a higher percent curve correction, and lower postoperative thoracic kyphosis. Conclusions Increased implant density is not predictive of postoperative curve magnitude in Lenke 2 AIS. Predictors of postoperative curve magnitude are sex and preoperative curve magnitude. Level of evidence Level III, retrospective observational

Scoliosis and Prognosis—a systematic review regarding patient-specific and radiological predictive factors for curve progression

Introduction Idiopathic scoliosis, defined as a > 10° curvature of the spine in the frontal plane, is one of the most common spinal deformities. Age, initial curve magnitude and other parameters define whether a scoliotic deformity will progress or not. Still, their interactions and amounts of individual contribution are not fully elaborated and were the aim of this systematic review. Methods A systematic literature search was conducted in the common databases using MESH terms, searching for predictive factors of curve progression in adolescent idiopathic scoliosis (“adolescent idiopathic scoliosis” OR “ais” OR “idiopathic scoliosis”) AND (“predictive factors” OR “progression” OR “curve progression” OR “prediction” OR “prognosis”). The identified and analysed factors of each study were rated to design a top five scale of the most relevant factors. Results Twenty-eight investigations with 8255 patients were identified by literature search. Patient-specific risk factors for curve progression from initial curve were age (at diagnosis < 13 years), family history, bone mineral status (< 110 mg/cm3 in quantitative CT) and height velocity (7–8 cm/year, peak 11.6 ± 1.4 years). Relevant radiological criteria indicating curve progression included skeletal maturity, marked by Risser stages (Risser < 1) or Sanders Maturity Scale (SMS < 5), the initial extent of the Cobb angle (> 25° progression) and curve location (thoracic single or double curve). Discussion This systematic review summarised the current state of knowledge as the basis for creation of patient-specific algorithms regarding a risk calculation for a progressive scoliotic deformity. Curve magnitude is the most relevant predictive factor, followed by status of skeletal maturity and curve location.

“Higher Pedicle Screw Density Does Not Result in Improved Curve Correction in Lenke 2 Adolescent Idiopathic Scoliosis”

Purpose: Higher pedicle screw density posterior spinal fusion (PSF) constructs have not been shown to result in improved curve correction in Lenke 1 and 5 adolescent idiopathic scoliosis (AIS) but do increase cost. The purpose of this study questioned whether higher screw density constructs improved curve correction and maintenance of correction in Lenke 2 AIS. Secondary goals were to identify predictive factors for correction and postoperative magnitude of curves in Lenke 2 AIS. Methods: We identified patients 11 to 17 years old who underwent primary PSF for Lenke 2 AIS between 2007 and 2017 who had minimum follow up of 2 years. Demographic and radiographic data were collected to perform regression and elimination analysis. Results: Thirty patients (21 Female, 9 male) were analyzed. Average age and SD at time of surgery was 14.0 ± 1.8 years (range, 11-17 years) and median follow-up was 2.8 years (IQR 2.1-4.0 years). Implant density did not predict final postoperative curve magnitude. Predictors of final postoperative curve magnitude were sex and preoperative curve magnitude. Predictors of percentage of correction of major curve were sex and age at the time of surgery. Predictors of final postoperative thoracic kyphosis were sex and percent flexibility preop. Females had lower final postoperative major curve magnitude, a higher percent curve correction, and lower postoperative thoracic kyphosis.Conclusions: Increased implant density is not predictive of postoperative curve magnitude in Lenke 2 AIS. Predictors of postoperative curve magnitude are sex and preoperative curve magnitude.Level of Evidence: Level III Retrospective Observational