A Decade in Review after Idiopathic Scoliosis Was First Called a Complex Trait-A Tribute to the Late Dr. Yves Cotrel for His Support in Studies of Etiology of Scoliosis

Association of IL‑6 and MMP‑3 gene polymorphisms with adolescent idiopathic scoliosis: A systematic review and meta‑analysis

The pathogenesis of adolescent idiopathic scoliosis (AIS) remains unclear. It has been found that interleukin-6 (IL-6) rs1800795 locus and matrix metalloproteinase-3 (MMP-3) rs3025058 locus gene polymorphisms may be associated with AIS susceptibility, which has been controversial and needs to be further confirmed by updated meta-analysis. The aim of the present study was to investigate the association of MMP-3 rs3025058 and IL-6 rs1800795 single nucleotide polymorphisms (SNPs) with susceptibility to AIS. All relevant articles that met the criteria were retrieved and included, and the publication dates were limited from January 2005 to December 2023. The allele frequencies and different genotype frequencies of IL-6 rs1800795 and MMP-3 rs3025058 loci in each study were extracted and statistically analyzed by ReviewManager 5.4 software, and the odds ratio (OR) and 95% confidence interval (95% CI) of different genetic models were calculated. The results of the meta-analysis showed that there was no significant association between the gene polymorphism of IL-6 rs1800795 locus and the pathogenesis of AIS. The allele 5A and genotype 5A5A of MMP-3 rs3025058 SNP were associated with AIS susceptibility (5A vs. 6A, OR=1.18; 95% CI, 1.04-1.33; 5A5A vs. 6A6A, OR=1.65; 95% CI, 1.23-2.21; and 5A5A vs. 5A6A + 6A6A, OR=1.54; 95% CI, 1.19-1.99). Results of subgroup analysis revealed that the allele 5A and genotype 5A5A of MMP-3 rs3025058 SNP were associated with AIS susceptibility in the Caucasian population, and the susceptibility of AIS was associated with the genotype 5A5A of MMP-3 rs3025058 SNP in an Asian population. There was no significant association between the gene polymorphism of IL-6 rs1800795 locus and the pathogenesis of AIS, while the allele 5A of MMP-3 rs3025058 locus was associated with the susceptibility to AIS, especially in the Caucasian population.

Handgrip strength assessment at baseline in addition to bone parameters could potentially predict the risk of curve progression in adolescent idiopathic scoliosis

Introduction

Adolescent idiopathic scoliosis (AIS) is characterized by deranged bone and muscle qualities, which are important prognostic factors for curve progression. This retrospective case-control study aims to investigate whether the baseline muscle parameters, in addition to the bone parameters, could predict curve progression in AIS.

Methods

The study included a cohort of 126 female patients diagnosed with AIS who were between the ages of 12 and 14 years old at their initial clinical visit. These patients were longitudinally followed up every 6 months (average 4.08 years) until they reached skeletal maturity. The records of these patients were thoroughly reviewed as part of the study. The participants were categorized into two sub-groups: the progressive AIS group (increase in Cobb angle of ≥6°) and the stable AIS group (increase in Cobb angle <6°). Clinical and radiological assessments were conducted on each group.

Results

Cobb angle increase of ≥6° was observed in 44 AIS patients (34.9%) prior to skeletal maturity. A progressive AIS was associated with decreased skeletal maturity and weight, lower trunk lean mass (5.7%, p = 0.027) and arm lean mass (8.9%, p < 0.050), weaker dominant handgrip strength (8.8%, p = 0.027), deranged cortical compartment [lower volumetric bone mineral density (vBMD) by 6.5%, p = 0.002], and lower bone mechanical properties [stiffness and estimated failure load lowered by 13.2% (p = 0.005) and 12.5% (p = 0.004)]. The best cut-off threshold of maximum dominant handgrip strength is 19.75 kg for distinguishing progressive AIS from stable AIS (75% sensitivity and 52.4% specificity, p = 0.011).

Discussion

Patients with progressive AIS had poorer muscle and bone parameters than patients with stable AIS. The implementation of a cut-off threshold in the baseline dominant handgrip strength could potentially be used as an additional predictor, in addition to bone parameters, for identifying individuals with AIS who are at higher risk of experiencing curve progression.

The Impact of Physical Activity on Adolescent Idiopathic Scoliosis

The prevalence of adolescent idiopathic scoliosis (AIS) is increasing, partly due to a lack of physical activity. In a cross-sectional study with 18,216 pupils (5th, 6th, and 8th grades) from four Croatian counties using the forward bend test (FBT; presumed AIS), the prevalence of AIS and its correlation with physical activity were evaluated. Pupils with presumed AIS were less physically active than their peers without scoliosis (p < 0.001). Abnormal FBT was more prevalent among girls than boys (8.3% vs. 3.2%). Boys were more physically active than girls (p < 0.001). Pupils with presumed AIS were less physically active than their peers without scoliosis (p < 0.001). A higher prevalence of presumed AIS was found among inactive or just recreationally active schoolchildren than among those engaged in organized sports (p = 0.001), girls especially. Pupils with presumed AIS were less active and had fewer weekly sports sessions than their peers without scoliosis (p < 0.001). Notably low prevalence of AIS was detected among pupils engaged in soccer (2.8%, p < 0.001), handball (3.4%, p = 0.002), and martial arts (3.9%, p = 0.006), while it was higher than expected in swimming (8.6%, p = 0.012), dancing (7.7%, p = 0.024), and volleyball (8.2%, p = 0.001) participants. No difference was detected for other sports. A positive correlation was found between time spent using handheld electronic devices and the prevalence of scoliosis (r_s = 0.06, p < 0.01). This study confirms the increasing prevalence of AIS, particularly among less athletic girls. Further, prospective studies in this field are required to explain whether the higher prevalence of AIS in these sports is due to referral or other aspects.

Urp1 and Urp2 act redundantly to maintain spine shape in zebrafish larvae

Urp1 and Urp2 are two neuropeptides, members of the Urotensin 2 family, that have been recently involved in the control of body axis morphogenesis in zebrafish. They are produced by a population of sensory spinal neurons, called cerebrospinal fluid contacting neurons (CSF-cNs), under the control of signals relying on the Reissner fiber, an extracellular thread bathing in the CSF. Here, we have investigated further the function of Urp1 and Urp2 (Urp1/2) in body axis formation and maintenance. We showed that urp1;urp2 double mutants develop strong body axis defects during larval growth, revealing the redundancy between the two neuropeptides. These defects were similar to those previously reported in uts2r3 mutants. We observed that this phenotype is not associated with congenital defects in vertebrae formation, but by using specific inhibitors, we found that, at least in the embryo, the action of Urp1/2 signaling depends on myosin II contraction. Finally, we provide evidence that while the Urp1/2 signaling is functioning during larval growth, it is dispensable for embryonic development. Taken together, our results show that Urp1/2 signaling is required in larvae to promote correct vertebral body axis, most likely by regulating muscle tone.

The role of school medicine in the early detection and management of adolescent idiopathic scoliosis

Objective

To analyze the trends in scoliosis screenings over 10 years (2010 vs. 2020). To assess the management of schoolchildren with a preliminary diagnosis of adolescent idiopathic scoliosis by school medicine specialists.

Methods

Historical data were used for the year 2009/2010, and a cross-sectional study was conducted during the school year 2019/2020 on 18,216 pupils of 5th, 6th, and 8th elementary school grades. A forward bend test was used to detect clinical features of scoliosis and some positive findings were referred to orthopedists or physiatrists for further evaluation.

Results

In the analyzed 10-year period abnormal forward bend test findings increased from 4.9 to 5.8% (by 18.4%; P < 0.001). While its prevalence escalated markedly in girls (from 5.8 to 8.3%; P < 0.001), a modest but significant decrease, from 3.8 to 3.2% (P = 0.018), was noted in boys. Most pupils had low to moderate curves, and its prevalence was some 6.5 times higher in girls (P < 0.001). The forward bend test positive predictive value was 84.7%. Discrete forward bend test aberrations were managed by school medicine specialists only.

Conclusion

While actively promoting scoliosis screening in children, we have shown that forward bend test is an acceptable tool for early adolescent idiopathic scoliosis detection in school medicine. In collaboration with other specialists and using additional diagnostic methods, school medicine specialists can ensure early detection and appropriate interventions, avoiding the potential harms of radiation exposure.