Relationship between Muscle Tone of the Erector Spinae and the Concave and Convex Sides of Spinal Curvature in Low-Grade Scoliosis among Children

Correlation of transverse rotation of the spine using surface topography and 3D reconstructive radiography in children with idiopathic scoliosis

PURPOSE

The relationship between axial surface rotation (ASR) measured by surface topography (ST) and axial vertebral rotation (AVR) measured by radiography in the transverse plane is not well defined. This study aimed to: (1) quantify ASR and AVR patterns and their magnitudes from T1 to L5; (2) determine the correlation or agreement between the ASR and AVR; and (3) investigate the relationship between axial rotation differences (ASR-AVR) and major Cobb angle.

METHODS

This is a retrospective study evaluating patients (age 8-18) with IS or spinal asymmetry with both radiographic and ST measurements. Demographics, descriptive analysis, and correlations and agreements between ASR and AVR were evaluated. A piecewise linear regression model was further created to relate rotational differences to Cobb angle.

RESULTS

Fifty-two subjects met inclusion criteria. Mean age was 14.1 ± 1.7 and 39 (75%) were female. Looking at patterns, AVR had maximal rotation at T8, while ASR had maximal rotation at T11 (r = 0.35, P = .006). Cobb angle was 24.1° ± 13.3° with AVR of - 1° ± 4.6° and scoliotic angle was 20.9° ± 11.5° with ASR of - 2.3° ± 6.6°. (ASR-AVR) vs Cobb angle was found to be very weakly correlated with a curve of less than 38.8° (r = 0.15, P = .001).

CONCLUSION

Our preliminary findings support that ASR measured by ST has a weak correlation with estimation of AVR by 3D radiographic reconstruction. This correlation may further help us to understand the application of transverse rotation in some clinical scenarios such as specific casting manipulation, padding mechanism in brace, and surgical correction of rib deformity.

Quantitative analysis of paravertebral muscle asymmetry and its correlation with spinal deformity in patients with degenerative lumbar scoliosis: a retrospective case-control study

Background

The degeneration and functional decline of paravertebral muscles (PVMs) are reported to be closely linked to the incidence of degenerative lumbar scoliosis (DLS), a spinal deformity of the mature skeleton. However, the functional role and degeneration of PVMs and their relationship to the development of spinal deformities remain controversial. Therefore, the present study analyzed the morphological changes in the PVMs of patients with DLS, and explored the relationship between PVM degeneration and spinal osseous parameters.

Methods

In this retrospective case-control study, we evaluated the PVM parameters of patients with DLS (n=120) and compared them with patients free of DLS (control group, n=120). The cross-sectional area (CSA) and computed tomography (CT) values of the PVM at the lumbar vertebra 1-5 levels were measured. Further, the lumbar scoliosis Cobb, lumbar lordotic, and apical vertebral rotation angles were measured on CT and radiographs in the DLS group, and the relationship between PVM changes and these factors was analyzed.

Results

In the control group, the PVM CSA and CT values differed insignificantly between the bilateral sides at all levels (P>0.05). In the DLS group, the CSAs of the multifidus (MF) and erector spinae (ES) were larger on the convex side than the concave side (P>0.05), whereas that of the psoas major (PM) was smaller on the convex side than the concave side (P<0.05). The CT value of the PVM was lower on the convex side at all levels (P<0.05). The CSA and CT values on both sides of the patients were lower in the DLS group than the control group at all levels (P<0.05). Further, the degree of PVM asymmetry at the apical vertebral level was positively correlated with the lumbar scoliosis (P<0.01) and apical vertebral rotation angles (P<0.05), but negatively correlated with the lumbar lordotic angle (P<0.05).

Conclusions

Asymmetric degeneration of the PVM was observed bilaterally in DLS patients, and the degeneration was more pronounced on the concave side than the convex side. This asymmetrical degeneration was closely associated with the severity of lumbar scoliosis, vertebral rotation, and loss of lumbar lordosis, and a stronger correlation was observed with the MF and ES than with the PM.

The role of the paraspinal muscles in the development of adolescent idiopathic scoliosis based on surface electromyography and radiographic analysis

BACKGROUND

Patients with idiopathic scoliosis commonly present with an imbalance of the paraspinal muscles. However, it is unclear whether this muscle imbalance is an underlying cause or a result of idiopathic scoliosis. This study aimed to investigate the role of paraspinal muscles in the development of idiopathic scoliosis based on surface electromyography (sEMG) and radiographic analyses.

METHODS

This was a single-center prospective study of 27 patients with single-curve idiopathic scoliosis. Posteroanterior whole-spine radiographs and sEMG activity of the erector spinae muscles were obtained for all patients in the habitual standing position (HSP), relaxed prone position (RPP), and prone extension position (PEP). The Cobb angle, symmetrical index (SI) of the sEMG activity (convex/concave), and correlation between the two factors were analyzed.

RESULTS

In the total cohort, the mean Cobb angle in the HSP was significantly greater than the mean Cobb angle in the RPP (RPP-Cobb) (p < 0.001), whereas the mean Cobb angle in the PEP (PEP-Cobb) did not differ from the RPP-Cobb. Thirteen patients had a PEP-Cobb that was significantly smaller than their RPP-Cobb (p = 0.007), while 14 patients had a PEP-Cobb that was significantly larger than their RPP-Cobb (p < 0.001). In the total cohort and two subgroups, the SI of sEMG activity at the apex vertebra (AVSI) in the PEP was significantly greater than 1, revealing significant asymmetry, and was also significantly larger than the AVSI in the RPP. In the RPP, the AVSI was close to 1 in the total cohort and two subgroups, revealing no significant asymmetry.

CONCLUSION

The coronal Cobb angle and the SI of paraspinal muscle activity in AIS patients vary with posture changes. Asymmetrical sEMG activity of the paraspinal muscles may be not an inherent feature of AIS patients, but is evident in the challenging tasks. The potential significance of asymmetric paraspinal muscle activity need to be explored in further research.

Current biomechanical theories on the etiopathogenesis of idiopathic scoliosis

PURPOSE

There is great controversy about the etiologic origin of adolescent idiopathic scoliosis. Multiple theories have been suggested, including metabolic aspects, endocrine dysfunction, neurological central abnormalities, genetic predisposition and epigenetic factors involved in the development of scoliosis. However, there has always been speculations based on human biomechanical behavior.

METHODS

In this article, we performed a literature review on the biomechanical traits of human posture, and the proposed theories that explain the special characteristics present in idiopathic scoliosis.

RESULTS

The current theory on the etiopathogeneis of AIS suggests that dorsally directed shear loads acting on a preexisting axial plane rotation, in a posteriorly inclined sagittal plane of a growing patient, together with disc maturation, collagen quality at this phase of development and immaturity of proprioception, is the perfect scenario to spark rotational instability and create the three-dimensional deformity that defines idiopathic scoliosis.

CONCLUSION

The unique spinal alignment of human bipedalism, gravity and muscle forces acting straight above the pelvis to preserve an upright balance, and the instability of the soft tissue in a period of growth development, is an appealing cocktail to try to explain the genesis of this condition in humans.

3D Back Contour Metrics in Predicting Idiopathic Scoliosis Progression: Retrospective Cohort Analysis, Case Series Report and Proof of Concept

Adolescent Idiopathic Scoliosis is a 3D spinal deformity commonly characterized by serial radiographs. Patients with AIS may have increased average radiation exposure compared to unaffected patients and thus may be implicated with a modest increase in cancer risk. To minimize lifetime radiation exposure, alternative imaging modalities such as surface topography are being explored. Surface topography (ST) uses a camera to map anatomic landmarks of the spine and contours of the back to create software-generated spine models. ST has previously shown good correlation to radiographic measures. In this study, we sought to use ST in the creation of a risk stratification model. A total of 38 patients met the inclusion criteria for curve progression prediction. Scoliotic curves were classified as progressing, stabilized, or improving, and a predictive model was created using the proportional odds logistic modeling. The results showed that surface topography was able to moderately appraise scoliosis curvatures when compared to radiographs. The predictive model, using demographic and surface topography measurements, was able to account for 86.9% of the variability in the future Cobb angle. Additionally, attempts at classification of curve progression, stabilization, or improvement were accurately predicted 27/38 times, 71%. These results provide a basis for the creation of a clinical tool in the tracking and prediction of scoliosis progression in order to reduce the number of X-rays required.

Factors Influencing the Duration of Rehabilitation in Infants with Torticollis-A Pilot Study

Background and Objectives: Torticollis is a common pediatric condition, with an incidence of 0.3-2.0%. Studies show that an adequate, tailored, and early treatment helps 90% to 95% of children recover before the first year of life and 97% of patients recover if treatment starts before the first six months. To identify the relationships between variables considered essential in the recovery process of infants with torticollis, we included factors such as the type of torticollis, age at onset of treatment, gender, birth weight, mode of delivery, fetal position in the uterus, the presence of craniofacial deformities, regions affected by postural asymmetries, and duration of the rehabilitation program. The hypothesis of the study is that early initiation of therapy can contribute to achieving favorable outcomes in the recovery process. Material and Methods: This retrospective cohort pilot study was conducted within a rehabilitation facility, spanning a duration of 1 year. The study involved a population of 41 children aged between 0 and 6 months. The rehabilitation program consisted of the application of Vojta therapy. Each session lasted 20 min, with a frequency of three times per week. Results: A total of 41% of those who started therapy in the first 3 months of life were fully recovered after 4-6 weeks of therapy. Of infants who started therapy at 5 and 6 months of age, 15% showed no improvement in measurements from 14 to 16 weeks of age, at which point the use of a cranial orthosis was recommended, and 23% experienced a plateau in measurements from 10 to 14 weeks, requiring the use of a cervical collar in conjunction with therapy. Conclusions: The findings from the study suggest that there may be a correlation between early initiation of therapy and favorable outcomes in the recovery process. The primary factors influencing the duration of recovery were identified as the presence of body asymmetries and the age at which therapy was initiated.

Relationship between stomatognathic alterations and idiopathic scoliosis: a systematic review with meta-analysis of observational studies

Purpose

The objective of this systematic review was to assess a possible relationship between stomatognathic alterations and idiopathic scoliosis (IS).

Design

This study is a systematic review with meta-analysis of observational studies.

Methods

The protocol of this systematic review with meta-analysis was registered in PROSPERO (CRD42022370593). A bibliographic search was carried out in the Pubmed (MEDLINE), Scopus, Web of Science and CINAHL databases using the MeSH terms 'Scoliosis' and 'Stomatognathic Disease'. The odds ratio (OR) of prevalence and standardized mean difference (SMD) were used to synthesize the results.

Results

Of 1592 studies located, 14 studies were selected with 3018 subjects (age: 13.9 years). IS was related to Angle's class II (OR = 2.052, 95% CI = 1.236-3.406) and crossbite (OR = 2.234, 95% CI = 1.639-3.045). Patients with malocclusion showed a higher prevalence of IS than controls (OR = 4.633, 95% CI = 1.467-14.628), and subjects with IS showed high overjet (SMD = 0.405, 95% CI = 0.149-0.661) and greater dysfunction due to temporomandibular disorders (SMD = 1.153, 95% CI = 0.780-1.527).

Conclusion

Compared with healthy controls, subjects with IS have twice the risk of suffering from occlusion disorders, present greater temporomandibular dysfunction and have a greater overjet in the incisors. Moreover, subjects with malocclusion have an IS prevalence up to four times higher. The systematic orofacial examination of patients with IS should be recommended.

Directed Versus Nondirected Standing Postures in Adolescent Idiopathic Scoliosis: Its Impact on Curve Magnitude, Alignment, and Clinical Decision-Making

STUDY DESIGN

Prospective study.

OBJECTIVE

To investigate the difference in major curve Cobb angle and alignment between directed and nondirected positioning for adolescent idiopathic scoliosis (AIS) and to evaluate implications on treatment decision-making.

SUMMARY OF BACKGROUND DATA

Proper positioning of patients with spinal deformities is important for assessing usual functional posture in standing, so management strategies can be customized accordingly. Whether postural variability affects coronal and sagittal radiologic parameters and the impact of posture on management decisions remains unknown.

PATIENTS AND METHODS

Patients with adolescent idiopathic scoliosis presenting for an initial consultation at a tertiary scoliosis clinic were recruited. They were asked to stand in two positions: passive, nondirected position; and directed position by the radiographer. Radiologic assessment included major and minor Cobb angle, coronal balance, spinopelvic parameters, sagittal balance, and alignment. Cobb angle difference >5° between directed and nondirected positioning was considered clinically impactful. Patients with or without such differences were compared. Overestimation or underestimation of the major curve (at 25° or 40°) by nondirected positioning were examined due to its relevance to bracing and surgical indications.

RESULTS

This study included 198 patients, with 22.2% experiencing Cobb angle difference (>5°) between positioning. The major curve Cobb angle was smaller in nondirected than directed positioning (median difference: -6.0°, upper and lower quartile: -7.8, 5.8), especially for curves ≥30°. Patients with a Cobb angle difference had changes in shoulder balance ( P =0.007) when assuming a directed position. Nondirected positioning had 14.3% of major Cobb 25° underestimated and 8.8% overestimated, whereas 11.1% of curves >40° were underestimated.

CONCLUSION

Strict adherence to a standardized radiographic protocol is mandatory for reproducing spine radiographs reliable for curve assessment, as a nondirected position demonstrates smaller Cobb angles. Postural variation may lead to overestimation, or underestimation, of the curve size which is relevant to both bracing and surgical decision-making.

LEVEL OF EVIDENCE

Level-II.

A scoping review of the different types of exercise programs proposed for the improvement of postural balance in adolescents with idiopathic scoliosis

BACKGROUND

Adolescent idiopathic scoliosis (AIS), which is the most common type of scoliosis, is a progressive disease that occurs in children aged 10-16 years. Abnormal curvature in AIS provokes spinal asymmetry of the upper body alignment and might deteriorate postural balancing and control ability.

OBJECTIVE

To evaluate the effect of exercise interventions on balance and postural stability in patients with adolescent idiopathic scoliosis.

METHODS

Embase, Scopus, Pubmed (Medline) and Web of Science databases were searched using the terms idiopathic scoliosis, physiotherapy, and balance. The articles selected were published in English in peer-reviewed journals from 2012 to July 2022.

RESULTS

Ten studies met the inclusion criteria. The PEDro scale values ranged from 2 to 6 (mean, 3.6), indicating a low level of scientific rigor. In the sample studies, spinal stabilization exercises were most often trialed (n= 3), followed by Schroth's exercise (n= 2), stretching and self-elongation exercise (n= 2), the exercise protocol of Blount and Moe, physiotherapeutic scoliosis-specific exercise, and proprioceptive neuromuscular facilitation exercise (all n= 1).

CONCLUSIONS

Physical therapists will be able to apply hippotherapy, Schroth exercise, physiotherapy scoliosis-specific exercise, trunk stabilization, proprioceptive neuromuscular facilitation exercise, spinal stabilization exercise, core stabilization exercise, and body awareness therapy to manage balance impairments in patients with adolescent idiopathic scoliosis, and further studies are needed to provide stronger evidence.

Vestibular Morphological Alterations in Adolescent Idiopathic Scoliosis: A Systematic Review of Observational Studies

Adolescent idiopathic scoliosis (AIS) is the most frequent pediatric spinal deformity. Its treatment still shows limited results due to the existent lack of knowledge regarding etiopathogenesis. Thus, the purpose of the study is to check the existence of vestibular morphological alterations among idiopathic scoliosis patients. To meet the objective, we performed this systematic review searching studies in PubMed Medline, SCOPUS, Web of Science, CINAHL Complete and SciELO until 15 September 2022. Articles that analyzed the morphology of the vestibular apparatus were selected, comparing subjects with AIS versus healthy subjects. Variables were selected that measured the orientation of the channels as well as the general conformation of the vestibular apparatus. One hundred and eighty-five records were retrieved in the preliminary searches, of which five studies were finally included, providing data from 154 participants (83 cases and 71 healthy controls) with a mean age 16.07 ± 2.48 years old. Two studies conclude that the superior and lateral semicircular canals are longer and thinner in patients with AIS. One study concluded that the measure between centers of superior and lateral canals and the angle whose vertex is placed the center of posterior canal were significantly shorter in subjects with AIS than in healthy controls in the left-side of vestibular apparatus. Two studies found an asymmetry in the verticality of the lateral canals on both sides in subjects with AIS, although it is not clear whether the left canal is in a more horizontal or vertical position. Patients with AIS seem to present morphological asymmetries of the vestibular apparatus, fundamentally on the left side. These anomalies seem to correlate with the location of the curve but not with its laterality or severity.

Comparison of Trunk Motion between Moderate AIS and Healthy Children

Analysis of kinematic and postural data of adolescent idiopathic scoliosis (AIS) patients seems relevant for a better understanding of biomechanical aspects involved in AIS and its etiopathogenesis. The present project aimed at investigating kinematic differences and asymmetries in early AIS in a static task and in uniplanar trunk movements (rotations, lateral bending, and forward bending). Trunk kinematics and posture were assessed using a 3D motion analysis system and a force plate. A total of fifteen healthy girls, fifteen AIS girls with a left lumbar main curve, and seventeen AIS girls with a right thoracic main curve were compared. Statistical analyses were performed to investigate presumed differences between the three groups. This study showed kinematic and postural differences between mild AIS patients and controls such as static imbalance, a reduced range of motion in the frontal plane, and a different kinematic strategy in lateral bending. These differences mainly occurred in the same direction, whatever the type of scoliosis, and suggested that AIS patients behave similarly from a dynamic point of view.