The effect of rigid versus flexible spinal orthosis on the gait pattern of patients with adolescent idiopathic scoliosis

No effects of four weeks of combined brace and Schroth therapy in moderate adolescent idiopathic scoliosis on plantar pressure distribution

BACKGROUND

Positive effects of brace treatments in adolescent idiopathic scoliosis patients on gait were proven.

AIM

Therefore, this study examined whether the influence of brace therapy in combination with Schroth therapy influencing the plantar pressure distribution, pre and post intensive rehabilitative inpatient treatment.

DESIGN

Prospective cohort study, longitudinal.

SETTING

Scoliosis rehabilitation clinic "Asklepios Katharina-Schroth-Klinik" (Bad Sobernheim, Germany).

POPULATION

Twenty (14f/6m) patients (12-16 years) had a medically diagnosed moderate idiopathic scoliosis (Cobb angle 20-50°, Median 30°) and an indication for combined brace and Schroth therapy with an inpatient stay (4 weeks) at the Asklepios Katharina Schroth Clinic (Germany).

METHODS

At the beginning (T1) and at the end of the stay (T2), the plantar pressure distribution with (A) and without wearing a brace (B) was recorded (walking distance 10 m).

RESULTS

No significant differences between the left and right foot were found at baseline (T1). The T1 - T2 comparison of one foot revealed significant differences (p ≤ 0.05 - 0.001, respectively) for (A): mean pressure right midfoot, loaded area total left foot, left midfoot, left inner ball of foot, right midfoot, impulse total right foot, right midfoot and for (B): mean pressure right midfoot, right outer ball of foot, loaded area total right foot, right heel, right midfoot, impulse right heel, right midfoot, right outer ball of foot.

CONCLUSIONS

A combined brace and Schroth therapy maintains the initial symmetrical plantar pressure distribution over the duration of four weeks since the significant differences fall within the range of measurement error.

CLINICAL REHABILITATION IMPACT

The insole measuring system can be used to objectively support therapeutic gait training as part of rehabilitation and to assess insole fitting based on foot shape. Due to its convenient handling and rapid data acquisition, it may be a suitable method for interim or follow-up diagnostics in the treatment of idiopathic scoliosis.

Lessons from the pandemic era: do we need new strategies to improve conservative treatment adherence in adolescent idiopathic scoliosis? A retrospective analysis

This study aims to examine whether the COVID-19 pandemic affected the adherence to conservative AIS treatment. Adolescent Idiopathic Scoliosis (AIS) is characterized by a lateral curvature of the spine of at least 10 degrees. Compliance rates in conservative treatments are influenced by various factors. From a database of AIS patients, we selected 30 AIS patients who were assessed before, during, and after the COVID-19 pandemic. Data regarding Cobb's angle, brace prescription, prescribed brace wear time, brace wear compliance, and time dedicated to sports activities were collected over a six-year period from January 2018 to December 2023, divided into three 2-year time periods (before, during, and after COVID-19). There was an increased percentage of AIS patients prescribed with a brace during the pandemic. However, no significant differences in Cobb's angle were observed. Additionally, the prescribed wear time showed a significant decrease from the pre-COVID period to the post-COVID period (p-value = 0.03). Wear compliance exhibited a decreasing trend from pre- to during- and post-COVID-19 periods without reaching statistically significant differences, and the time dedicated to sports statistically significantly decreased. These differences were statistically significant when comparing the pre- vs. post- and pre- vs. during-COVID-19 periods (p-values 0.01, 0.04, respectively). Our study highlights changes in AIS conservative treatment during and after the COVID-19 pandemic. The increase in the number of patients prescribed with a brace during the pandemic, although not supported by an increase in Cobb's angle, may be attributed to the concerns about regular monitoring during the reduction of rehabilitation services. The observed decreases in brace compliance and involvement in sport activities, which persisted even in the post-pandemic period, emphasizes the lasting impact of the pandemic on AIS management, necessitating innovative approaches to address these ongoing concerns.

The Incidence of Bracing Treatment on Static and Dynamic Baropodometric Parameters in Adolescent Idiopathic Scoliosis

Postural balance is an important but not well-studied concept in the treatment of adolescent scoliosis. The aim of this study was to assess whether conservative treatment with Sforzesco bracing induced negative perturbations on postural stability, as related to static, postural, and dynamic baropodometric indicators. Twelve subjects (12 females, aged 11−16) with moderate AIS, were selected among a group of 97 patients. Inclusion criteria were: (1) confirmed diagnosis of moderate AIS (Cobb angle of 21° to 35° for the primary curve); (2) thoracic or thoracolumbar primary curve; (3) skeletal immaturity with growth cartilage visible on pretreatment radiographs (Risser < 5); (4) chronological age between 11 and 16 years; and (5) Sforzesco bracing treatment. All patients underwent a physical examination and radiological measurements with anteroposterior and lateral scans. Static, postural, and dynamic assessments were performed twice by barefoot patients, with and without Sforzesco bracing. Comparison between demographic, anthropometric, and clinical data highlighted a homogeneity of the sample. We evaluated the point of maximum pressure with and without bracing and found no statistically significant differences (p value = 0.22). In postural measurements, the laterolateral oscillations, anteroposterior oscillations, and average speed of oscillations were evaluated, comparing measurements with and without bracing. There were no statistically significant differences, except for the mean rate of oscillation, which was slightly increased in the recordings with a brace compared to those without a brace, p value = 0.045. Our findings show no statistically significant differences (p > 0.05) in static, postural, and dynamic baropodometric indicators.

Gait oxygen consumption in adolescent idiopathic scoliosis and the effect of brace use

BACKGROUND

Despite studies showing that gait is affected in adolescent idiopathic scoliosis (AIS), it remains unclear whether gait oxygen consumption is altered.

RESEARCH QUESTION

The aims of the present study were to compare energy consumption during gait between subjects with AIS and healthy controls, and to examine the effect of brace use on gait energy expenditure.

METHODS

This prospectively designed study included 15 AIS and 15 healthy girls, whose ages ranged from 10 to 16 years old and Cobb angles from 20 and 45°. At the end of the first month of brace use for the first time in individuals with AIS, oxygen consumption was measured with and without brace use on a treadmill at a gait speed of 4 km.h^-1 using a metabolic analyzer.

RESULTS

There was no statistically significant difference in gross and net gait oxygen consumption measurements between AIS and healthy individuals or between individuals with AIS with or without brace use (p >  0.05).

SIGNIFICANCE

After one month of brace treatment, AIS is not associated with an additional metabolic load with or without the brace during gait when compared to healthy subjects.

Position of the major curve influences asymmetrical trunk kinematics during gait in adolescent idiopathic scoliosis

BACKGROUND AND PURPOSE

Adolescent idiopathic scoliosis (AIS) is a structural, lateral curvature with rotation of the spine that develops around puberty. The influence of this spinal deformity on three-dimensional trunk movements during gait has not yet been elucidated. The aim of this study was to determine the influence of spinal curve pattern (single thoracic curve vs. single lumbar curve) on trunk kinematics during gait.

METHODS

Twenty-two patients with a single thoracic curve (Lenke type 1) and 17 patients with a single lumbar curve (Lenke type 5) were included in this study. Trunk symmetry in the sagittal, coronal, and transverse planes during gait was evaluated using an optoelectronic motion capture system.

RESULTS

In the type 1 group, the trunk was significantly rotated towards the concave side in the transverse plane during gait (mean difference of transverse rotation angle between concave side load and the convex side load, 8.8±0.6°, p<0.01). In the type 5 group, the trunk was significantly rotated towards the convex side in the coronal plane throughout the stance phase of gait (mean difference of coronal inclination angle, 1.9±0.3°, p<0.05).

CONCLUSIONS

The AIS patients with a single thoracic curve showed asymmetrical trunk movement in the transverse plane, and patients with a single lumbar curve showed asymmetrical trunk movement in the coronal plane. These results indicate that the spinal curve pattern influenced trunk kinematics, and suggest that the global postural control strategy of patients with AIS differs according to the curve pattern.

Evaluation of the influences of various force magnitudes and configurations on scoliotic curve correction using finite element analysis

Scoliosis is a lateral curvature in the normally straight vertical line of the spine, and the curvature can be moderate to severe. Different treatment can be used based on severity and age of subjects, but most common treatment for this disease is using orthosis. To design orthosis types of force arrangement can be varied, from transverse loads to vertical loads or combination of them. But it is not well introduced how orthoses control scoliotic curve and how to achieve the maximum correction based on force configurations and magnitude. Therefore, it was aimed to determine the effect of various loads configurations and magnitudes on curve correction of a degenerative scoliotic subject. A scoliotic subject participated in this study. The CT-Scan of the subject was used to produce 3D model of spine. The 3D model of spine was produced by Mimics software and the finite element analysis and deformation of scoliotic curve of the spine under seven different forces and in three different conditions was determined by ABAQUS software. The Cobb angle in scoliosis curve decreased significantly by applying forces. In each condition depends on different forces, different corrections have been achieved. It can be concluded that the configurations of the force application mentioned in this study is effective to decrease the scoliosis curve. Although it is a case study, it can be used for a vast number of subjects to predict the correction of scoliosis curve before orthotic treatment. Moreover, it is recommended that this method and the outputs can be compared with clinical findings.

Balance and gait performance of scoliotic subjects: A review of the literature

INTRODUCTION

Scoliosis is one of the common spinal deformities and considered as lateral curvature of the spine. Scoliosis lead to changes in the synergy between body segments, spinal anatomy, left-right trunk symmetry and cause pathological gait pattern [1,4,5-7]. Scoliosis is a structural deformity, so it can alter center of mass (COM) position and weight distribution on lower limbs. This suggests that scoliotic patients show the poorer stability rather aged match normal group. It was controversial that scoliosis influences the balance and gait performances, and also the effects of brace on these parameters. Therefore, it was aimed to evaluate the available literatures on balance and gait of scoliotic subjects.

MATERIALS AND METHODS

We conducted a search via PubMed, Google scholar and ISI web of knowledge to identify studies on scoliosis field and the effect of this deformity on kinetic and kinematic parameters as well as the influence of bracing on mentioned parameters. Some key words such as kinetic, kinematic, gait, stability, and walking were used in combination with scoliosis. The publication dates of the full-length articles were between 1998 and 2014. Down and Black tool was used to evaluate the quality of the articles.

RESULTS

Our multiple Medline searches led to the find out 54 papers that 26 of which were relevant based on title and abstract. Based on their references, we retrieved 6 more articles. We ultimately included 31 articles in this literature review. The number of studies regarding the influence of brace on kinetic and kinematic parameters in scoliotic subject was small. Based on the results of various studies, there is no correlation between gait pathology and scoliotic curve direction, no difference between stability of scoliotic and normal subjects and no difference between range of motions of lower limb joints in scoliotic subjects while walking with and without orthosis.

CONCLUSION

There was a not sufficient robust evidence to judge about the influence of scoliosis deformity on kinetic and kinematic parameters. However, it should be emphasized that use of orthosis may influence the symmetry of gait and improve standing stability in adult with idiopathic scoliosis.

Efficacy of corrective spinal orthoses on gait and energy consumption in scoliosis subjects: a literature review

BACKGROUND

Adolescent idiopathic scoliosis (AIS) is a progressive growth disease that affects spinal anatomy, mobility, and left-right trunk symmetry. As a consequence, AIS can modify human gait. Spinal orthoses are a commonly used conservative method for the treatment of AIS.

OBJECTIVE

This review evaluated the AIS spinal orthosis literature that involved gait and energy consumption evaluations.

STUDY DESIGN

Literature review.

METHOD

According to the population intervention comparison outcome measure methods and based on selected keywords, 10 studies met the inclusion criteria.

RESULTS

People with AIS who wore a spinal orthosis, compared with able-bodied participants, walked slower with decreased hip and pelvic movements, decreased hip mediolateral forces, ground reaction force asymmetry, and excessive energy cost. Pelvis and hip frontal plane motion decreased when wearing an orthosis. Hip and pelvis movement symmetry improved when using an orthosis. Ankle and foot kinematics did not change with orthotic intervention. People with AIS continued to have excessive energy expenditure with an orthosis.

CONCLUSION

Spinal orthoses may be considered for improving the walking style, although energy cost does not decline following the orthotic intervention. Implications for Rehabilitations Problems related to scoliosis include reduced quality of life, disability, pain, postural alterations, sensory perturbations, standing instability and gait modifications. Wearing corrective spinal orthoses in AIS subjects produce a reduction in walking speed and cadence, increase in stride length and reduction of gait load asymmetry compared to without brace condition. Spinal orthoses do not decline excessive energy expenditure to walk versus without it.

Effect of long-term orthotic treatment on gait biomechanics in adolescent idiopathic scoliosis

BACKGROUND CONTEXT

A previous study showed subtle biomechanical changes in the gait of unbraced adolescent idiopathic scoliosis (AIS) patients such as a reduction of pelvic, hip, knee, and ankle displacements. However, lumbopelvic muscles' timing activity was bilaterally increased during gait and correlated to excessive oxygen consumption as compared with healthy subjects. Usually, a brace, when indicated, is worn strictly for 22 hours every day in skeletally immature idiopathic scoliotic girls. To our knowledge, no study has assessed the long-term brace effect (6 months) on functional activities such as level walking.

PURPOSE

To assess the stiffening effects of 6 months' brace wearing on instrumented gait analysis in girls with thoracolumbar/lumbar adolescent idiopathic scoliosis.

STUDY DESIGN/SETTING

Clinical prospective study.

PATIENT SAMPLE

Thirteen girls diagnosed as progressive adolescent idiopathic scoliosis with left thoracolumbar/lumbar curves (curves ranging 25°-40°).

OUTCOME MEASURES

All patients underwent a radiographic and instrumented gait analysis, including assessment of kinematics, mechanics, electromyography (EMG), and energetics of walking.

METHODS

The scoliotic girls were prospectively studied at S1 (before bracing) and 6 months later at S2 (out-brace: treatment effect). The gait parameters were compared with those of 13 matched healthy girls. A t paired test was conducted to evaluate the effect of the 6-month orthotic treatment in AIS girls. Student t test was performed to compare the scoliotic group at S2 and the healthy subjects to identify if the observed changes in gait parameters meant improvement or worsening of gait.

RESULTS

After 6 months of orthotic treatment in AIS, thoracolumbar/lumbar curves and apical rotation remained reduced by 25% and 61%, respectively. During gait, frontal pelvis and hip motions were significantly increased. Muscular mechanical work increased becoming closer but still different as compared with healthy subjects. Bilateral lumbopelvic muscles were almost 40% more active in AIS at S1 compared with healthy subjects and did not change at S2 except for the erector spinae muscles EMG activity, which decreased significantly. Energy cost exceeded by 30% in AIS at S1 compared with healthy subjects and did not change at 6 months' follow-up.

CONCLUSIONS

After 6 months of orthotic treatment, in an out-brace situation, the main structural thoracolumbar/lumbar curve remained partly corrected. Frontal pelvis and hip motion increased, contributing to an improvement of muscular mechanical work during walking. EMG activity duration of lumbopelvic muscles did not change except for the erector spinae muscles, which was decreased but without any beneficial change in the energy cost of walking. In summary, brace treatment, after 6 months, did not significantly influence the gait variables in AIS girls deleteriously, but did not reduce the excessive energy cost, which was 30% above the values of normal adolescents.

3D analysis of brace treatment in idiopathic scoliosis

PURPOSE

We have evaluated the effect of bracing in scoliosis on coronal alignment in a cohort of patients. Current literature has not described the specific effect of bracing on the 3D shape of the scoliotic curves. The purpose of this study was to analyze the variability of the 3D effect of bracing on idiopathic scoliosis.

MATERIALS AND METHODS

The spines of 30 patients with adolescent idiopathic scoliosis were reconstructed using biplanar stereoradiography with and without the brace. The Cobb angle, sagittal and pelvic parameters and transverse plane parameters were calculated. The variability and the mean values of each parameter, with and without a brace, were analyzed and compared using a student t test.

RESULTS

The Cobb angle improved in 50% of patients but remained unchanged in 50% cases. In 90% of the cases lordosis was decreased. The thoracic kyphosis was decreased in 26% cases, unchanged in 57% of cases and increased in 17% cases. The AVR was improved (>5°) in 26% cases, worsened in 23% and unchanged in 50%. Only the differences of Cobb angle and the lordosis were statistically significant.

CONCLUSIONS

Global statistics of this study concur with the literature. The Cobb angle was significantly improved. It also showed a significant hypolordotic effect. However, the results showed a high variability of the brace treatment effect in almost every parameter. Analysis of this variability by means of 3D reconstructions instead of global statistics should help characterize the mechanisms of correction of brace treatment.

Very short-term effect of brace wearing on gait in adolescent idiopathic scoliosis girls

PURPOSE

Adolescent idiopathic scoliotic (AIS) deformity induces excessive oxygen consumption correlated to a bilateral increase of lumbo-pelvic muscles timing activity (EMG) during gait. Wearing a brace, the usual treatment for AIS, by supporting the spine and the pelvis, would generate lumbo-pelvic muscular relaxation and consequently reduce excessive oxygen consumption. The purpose of this study was to evaluate the short-term effect of bracing on gait biomechanics in scoliotic spine when compared with normal braced spine.

METHODS

Thirteen healthy volunteers were compared to 13 AIS girls. In both samples, gait analysis was assessed using a three-dimensional motion analysis, including synchronous kinematic, electromyographic, mechanical and energy measurements, first without brace, then wearing a brace.

RESULTS

For scoliotic patients, comparison of in-brace and out-brace situations revealed a significant decrease of frontal pelvis (p < 0.001), hip (p < 0.001) and shoulder (p = 0.004) motion in brace associated with a significant reduction of pelvis rotation (p = 0.003). However, the brace did not change significantly the lumbo-pelvic muscle activity duration (EMG) or the mechanical and energetic parameters. Transversal pelvis motion was reduced by 39% (p = 0.04), frontal hip and shoulder motions by 23% (p = 0.004) and 30% (p = 0.01) respectively, and energy cost of walking remained increased by 37% in braced AIS girls relatively to braced healthy subjects. Mechanical and electromyographic variables were not significantly different between the two braced populations during gait except for the gluteus medius muscle that showed bilaterally an increase of duration of electrical activity in healthy subjects and contrarily a decrease in AIS patients (healthy: -3.5 ± 9.6% of gait cycle vs. scoliotic: 3.7 ± 7.7% of gait cycle; p = 0.04).

CONCLUSIONS

Bracing changed neither the oxygen consumption nor the timing of the lumbo-pelvic muscles activity in both groups during gait. However, in brace the timing activity of bilateral gluteus medius muscles tended to decrease in AIS patients and increase in healthy subjects. Moreover, braced AIS patients had more restricted frontal hips and shoulder motion as well as pelvis rotation than braced healthy subjects.

Prospective evaluation of physical activity in patients with idiopathic scoliosis or kyphosis receiving brace treatment

Bracing is an established method of conservative treatment for adolescent idiopathic scoliosis and kyphosis. Compliance among adolescents is frequently inadequate due to the discomfort of wearing a brace, cosmetic issues, and fear on the part of patients and parents that bracing may reduce everyday physical activities. The aim of this prospective, controlled study was to objectify the impact of spinal bracing on daily step activity in patients receiving conservative treatment for adolescent idiopathic scoliosis (AIS) or adolescent kyphosis (AK). Forty-eight consecutive patients (mean age 13.4 ± 2.3 years), consisting of 38 AIS patients (33 girls, 5 boys) and 10 AK patients (6 girls, 4 boys) were included. Once the decision to carry out bracing had been taken and while the patients were waiting for the individual brace to be built, step activity was assessed without braces by means of step activity monitoring (SAM) for seven consecutive days. After 8 weeks of brace wearing, step activity was assessed during regular brace treatment, again for seven consecutive days. In addition, brace-wearing times were simultaneously recorded using temperature probes implanted in the braces to measure compliance. Before and during brace treatment, patients completed the Scoliosis Research Society (SRS-22) questionnaire. The SAM was worn for an average of 12.7 ± 1.5 h/day during the first measurement and 12.3 ± 1.9 h on average during the second measurement. The mean gait cycles (GCs) per day and per hour before treatment were 5,036 ± 1,465 and 395 ± 105, respectively. No significant reduction in step activity was found at the follow-up measurement during bracing, at 4,880 ± 1,529 GCs/day and 403 ± 144 GCs/h. Taking the 23-h recommended time for brace wearing as a basis (100%), patients wore the brace for 72.7 ± 27.6% of the prescribed time, indicating an acceptable level of compliance. Girls showed a higher compliance level (75.6 ± 25.6%) in comparison with boys (56.7 ± 31.9%), although the difference was not significant (P = 0.093). The SRS-22 total score showed no differences between the two measurements (2.57 ± 0.23 vs. 2.56 ± 0.28). Implementing a simultaneous and objective method of assessing step activity and brace-wearing times in everyday life proved to be feasible, and it expands the information available regarding the impact of bracing on patients' quality of life. The results clearly show that brace treatment does not negatively interfere with daily step activity in AIS and AK patients. This is an important finding that should help reduce patients' and parents' worries concerning bracing.

A comparison of thoracolumbosacral orthoses and SpineCor treatment of adolescent idiopathic scoliosis patients using the Scoliosis Research Society standardized criteria

BACKGROUND

SpineCor is a relatively new bracing system that uses dynamic bracing concepts in the treatment of adolescent idiopathic scoliosis (AIS). Limited data are available regarding its effectiveness. This study compared treatment outcomes of 2 groups of AIS patients treated via either a conventional rigid thoracolumbosacral orthoses (TLSO) or a SpineCor nonrigid orthosis.

METHODS

We identified 2 scoliosis patient cohorts: 35 patients treated with a TLSO and 32 patients treated with a SpineCor orthosis. All patients included in these groups conformed with the Scoliosis Research Society (SRS) standardized criteria for AIS bracing: (1) Risser < or =2, (2) curve magnitude 25 to 40 degrees, (3) age > or =10 years. Outcomes were SRS standardized with failure being defined as curve progression > or =6 degrees, or ever exceeding 45 degrees, or having surgery recommended before skeletal maturity. All patients were followed through the completion of brace treatment or attainment of other treatment end points. The Yates corrected chi test and unpaired t test were used for data analysis.

RESULTS

The 35 patients (32 girls, 3 boys) in the TLSO group had an average age of 13 years (range: 11.1-16.8) and an average primary curve magnitude of 33 degrees (range: 25-40 degrees). Follow-up averaged 2 years (range: 8-61 m) from the beginning of brace treatment. The 32 patients (28 girls, 4 boys) in the SpineCor group had an average age of 13 years (range: 11-15.2) and an average primary curve magnitude of 31 degrees (range: 25-40 degrees). Follow-up for this group averaged 2 years and 6 months (range: 13-73 mo) from the beginning of brace treatment. No significant difference (P=0.75) was found using the more strict outcome measure (< or =5-degree curve progression) as the success rates were 60% (21/35) for TLSO and 53% (17/32) for SpineCor. Similarly, no significant difference (P=0.62) was found using the more liberal outcome measure (never reached 45 degrees) as the success rates were 80% (28/35) for TLSO and 72% (23/32) for SpineCor.

CONCLUSIONS

We were unable to identify any significant differences in brace treatment outcomes when comparing TLSO and SpineCor treated patients.

Objective compliance of adolescent girls with idiopathic scoliosis in a dynamic SpineCor brace

PURPOSE

Dynamic SpineCor was designed to overcome the disadvantages of rigid orthoses-bulkiness, physical constraint and warming-and to improve the acceptance and compliance as limiting factors of brace treatment. Those theoretical benefits have not been proved by compliance studies yet.

METHODS

SpineCor braces of 12 adolescent scoliotic girls were equipped with flexible temperature loggers, which were sandwiched between gel foam and the brace's pelvic base. Patients and parents were blinded for the observation period of 14 days and gave post-hoc consent. The logger yielded 672 time-stamped values at 30-min intervals. Pilot testing revealed values beyond the 30°C threshold as indicative for brace wear.

RESULTS

The average overall compliance (% wearing hours/prescribed 23 h) was 54% ± 22.3 (range, 11.8-95.8%). The youngest patients (aged 10-12 years) were significantly more compliant than the others (P < 0.05). Most patients had a scattered wearing pattern: one was a day-wearer, one a night-wearer and only the two high adherers showed a consistent daily pattern. There was no significant difference between weekdays, weekdays and weekends, nor between day and night wear.

CONCLUSION

The current study showed that the compliance of patients in a dynamic SpineCor is as limited as in a conventional brace. This is in line with earlier data on patients' SpineCor and rigid brace acceptance evaluated by a questionnaire and on temperature logging in rigid braces.

Gait in thoracolumbar/lumbar adolescent idiopathic scoliosis: effect of surgery on gait mechanisms

For patients whose scoliosis progresses, surgery remains the ultimate way to correct and stabilise the deformity while maintaining as many mobile spinal segments as possible. In thoracolumbar/lumbar adolescent idiopathic scoliosis (AIS), the spinal fusion has to be extended to the lumbar spine. The use of anterior spinal fusion (ASF) instead of the classic posterior fusion (PSF) may preserve more distal spinal levels in attempt to limit the consequences of surgery on trunk mobility. The effects of surgery on body shape, pain and the decompensation phenomenon have all been well evaluated. Very few studies have addressed the effect of ASF or PSF on basic activities, such as walking. Before any treatment, AIS patients already have reduced pelvis, hip and shoulder motion when walking at a normal speed compared with adolescents without scoliosis (control group). Additionally, they have longer contraction time of the lumbar and pelvic muscles leading to an excessive energy cost and reduced muscle efficiency. In addition, if these changes are associated with spinal stiffness, spinal fusion could further negatively affect this pre-surgical inefficient walk. The goals of this study were (a) to compare pre- and 1-year post-surgery conditions in order to assess the effects of spinal arthrodesis on gait parameters and (b) to compare the anterior versus the posterior surgical approaches. Nineteen young females with thoracolumbar/lumbar AIS were assessed by radiological and clinical examination and by conventional gait analysis before surgery and at almost 12 months after surgery. Seven subjects underwent surgery using ASF and 12 using PSF. Three-dimensional gait analysis was performed on a motor-driven treadmill at spontaneous self-selected speed to record kinematic, electromyographic (EMG), mechanical and energetic measurements synchronously. Although it was expected that the instrumentation would modify the characteristics of normal walking, this study showed that surgery does not induce asymmetric gait or any significant differences between the ASP and the PSF surgery groups. One year after surgery, the changes observed consisted of improvements in the gait and mechanical parameters. In the PSF group, 11-14 vertebrae were fused while only 3-4 were fused in the ASF group. In both AIS groups, step length was increased by 4% and cadence reduced by 2%. There was a slight increase in pelvis and hip frontal motion. Only the transverse shoulder motion was mildly decreased by 1.5 degrees . All the other gait parameters were left unchanged or were improved by surgery. Notably, the EMG timing activity did not change. The total muscular mechanical work (W (tot)) increased by 6% mainly due to the external work (W (ext)), i.e. the work performed by the body muscles to move the body in its surroundings. The energy cost, although showing a tendency towards a reduction, remained globally excessive, probably due to the excessive co-contraction of the lumbo-pelvic muscles.

Effects of short-term brace wearing on the pendulum-like mechanism of walking in healthy subjects

Progressive spinal deformities, such as scoliosis, often need orthotic management to prevent deterioration. Such braces may alter spinal segmental movements, which contribute in minimizing energy requirements during gait. The goal of this study was to isolate the immediate effect of bracing on mechanical work and energy cost in 13 healthy subjects. Gait was assessed by a conventional motion analysis system. Our results showed a decrease in pelvis and shoulder motion, an increase in external work, and an alteration in pendulum-like mechanism of walking when wearing the brace. However, no significant difference was observed in total mechanical work, electromyographic activity and energy cost. The loss of efficiency of this pendulum mechanism could be due to the reduction of pelvis and shoulder motion brought about by the brace.