Effects of the Schroth exercise on the Cobb’s angle and vital capacity of patients with idiopathic scoliosis that is an operative indication

Abstract

[Purpose] The purpose of this study was to investigate the effects of the Schroth exercise on the Cobb’s angle and vital capacity of patients with growing idiopathic scoliosis, an operative indication. [Subjects] Five idiopathic scoliosis patients with a Cobb’s angle of the thoracic vertebra of 40 degrees or higher and Risser sign stage 3 or higher. [Methods] The Schroth exercise was applied 3 times a week for 12 weeks. We measured the thoracic trunk inclination, Cobb’s angle, and vital capacity before and after the exercise program. [Results] The thoracic trunk rotation angle decreased from 11.86 ± 3.32° to 4.90 ± 1.91° on average, the thoracic Cobb’s angle decreased from 42.40 ± 7.86° to 26.0 ± 3.65° on average, and the vital capacity also increased from 2.83 ± 1.23° to 4.04° ± 1.67° on average. All these effects were significant. [Conclusion] The 12-week Schroth exercise caused significant effects in the thoracic trunk inclination, Cobb’s angle, and vital capacity. The conservative treatment method was found to be effective even at a 40 degree or higher Cobb’s angle. In the future, universal exercise approach methods and preventive training for the treatment of scoliosis should be developed further.

INTRODUCTION

Scoliosis refers to a 3-dimensional deformation of the natural bending of the spine¹⁾. In the clinical setting, the Cobb’s angle analysis method, which is a valid analysis of the size of the lateral bending through radiographic methods, is generally used²⁾. Minor scoliosis with less than a 20° Cobb’s angle requires periodic observation, and scoliosis with a Cobb’s angle of 20–40° requires the wearing of an orthosis to prevent progress. If the Cobb’s angle is greater than 40°, it indicates the need of surgery³⁾. If scoliosis is detected and treated early, most patients do not need surgical treatment⁴⁾; in some cases, surgical treatment may have poorer results⁵⁾. The orthosis treatment, which is the first stage of scoliosis treatment, can cause spondylosis and loss of the surrounding muscles⁶⁾. If this limitation of normal movement occurs in growing adolescents, it could cause undesirable results⁷⁾. Scoliosis causes deformations of the spinal column and structures⁸⁾, decreases in spinal flexibility by changing the characteristics of the erector spinae muscle⁹⁾, and leads to imbalances of the trunk and pelvis depending on the shape and angle of the scoliosis¹⁰⁾. Furthermore, it has been reported that correction and respiratory treatment are essential because of the bending of the thoracic cage, which weakens the respiratory muscle and lowers cardiopulmonary function¹¹⁾. Various core and breathing exercises are used to treat scoliosis^{12, 13)}. The treatment effects of the Schroth therapy, a recent therapeutic exercise, have been reported^{14, 15)}. Often referred to as a 3-dimensional therapy, the Schroth exercise improves the trunk shape and respiratory ability by applying “rotational breathing”¹⁶⁾, and it has been reported to improve the function of the thoracic wall and the symptoms of the respiratory system¹⁷⁾. Many studies have investigated the improvement effects of the Schroth exercise on Cobb’s angle and vital capacity in scoliosis patients, but most studies were on patients whose Cobb’s angle was smaller than 30° or the studies combined the Schroth exercise with orthosis treatment. Studies on subjects with a 40° or higher Cobb’s angle who require surgery are still insufficient. Therefore, this study investigated the effects of the Schroth exercise therapy in patients with scoliosis as a surgical indication for the improvement of their Cobb’s angle and vital capacity.

SUBJECTS AND METHODS

The subjects in this study were 5 female students among patients with thoracic scoliosis whose Cobb’s angle was greater than 40° and whose Risser sign was stage 3 or higher treated at N Hospital in Daegu, South Korea (Table 1). Every subject was explained the purpose of this study and the exercise method and voluntarily signed the informed consent form before participating in this experiment, according to the ethical standards of the Declaration of Helsinki. We excluded individuals who had neurological findings or an operation, who recently received surgical treatment, who wore an orthosis, or who were periodically taking medicine from our study. Subjects performed the Schroth exercise 3 times a week for 12 weeks. Each 60-minute session consisted of preparation (cat walking and breathing exercise: 10 min), stretching (stretching the chest part: 5 min), the main exercise (laying right click concave, laying aside static postural control training, sitting posture adjustment exercise, and muscle cylinder: 40 min), and wrap-up (moving ribs: 5 min). We applied the Schroth exercise in accordance with the bending shape of each subject, along with 3-dimensional Schroth rotational breathing¹⁸⁾. We measured Cobb’s angle, with the patient standing straight, using a radiography apparatus (CR 85-X, USA). The trunk rotation angle was measured through the Adam’s forward bending test using a scoliometer (OSI, USA). The vital capacity was measured 3 times after 3 or more breathing exercises in a 90° sitting position using CardioTouch 3000S (BIONET, Korea); we recorded the average values. To compare the changes in Cobb’s angle, thoracic trunk rotation angle, and vital capacity after the Schroth exercise, we analyzed the data using SPSS 18.0. We used a 1-sample paired t-test with a significance level of p <0.05.

Table 1. General characteristics of the subjects.

	N=10 (Female: 6)
Age (years)	22.60±1.83
Height (cm)	167.00±7.45
Weight (kg)	63.80±12.01
Cobb’s angle (°)	17.03±0.54
Risser sign (phase)	3.23±1.04

Mean±SD: mean±standard deviation

RESULTS

The patients in our study had a thoracic trunk rotation angle decrease from 11.86 ± 3.32° to 4.90 ± 1.91° on average, Cobb’s angle decrease from 42.40 ± 7.86° to 26.00 ± 3.65° on average, and vital capacity increase from 2.83 ± 1.23 l to 4.04 ± 1.67 l on average. All these effects were statistically significant (p < 0.05; Table 2).

Table 2. Pre- and post-intervention comparisons (Unit: ratio).

	Pre-test	Post-test
Trunk rotation angle (°)	11.86±3.32	4.90±1.91*
Cobb’s angle (°)	42.40±7.86	26.00±3.65*
Vital capacity (l)	2.83±1.23	4.04±1.67*

Mean±SE, *Significant difference from pre-test, p<0.05

DISCUSSION

In this study, to examine the effects of the Schroth exercise on Cobb’s angle, thoracic trunk rotation angle, and vital capacity of patients with scoliosis as a surgical indication, the subjects performed the Schroth exercise 3 times a week for 12 weeks.

The Schroth exercise has the advantage of correcting the posture according to the bending type and is an effective mechanism to facilitate the correction of posture in the 3 dimensions of scoliosis¹⁹⁾. The Schroth 3-dimensional rotational breathing exercise induces significant increases in rib movements and vital capacity and induces a significant increase in the sagittal breathing exercise for the improvement of flat back²⁰⁾. Furthermore, the Schroth 3-dimensional exercise approach has been proven to decrease the progress of idiopathic scoliosis, improve Cobb’s angle and resolve pain^{21, 22)}, and reduce the prescription of orthosis²³⁾. Borysov et al. measured Cobb’s angle with a scoliometer after applying the Schroth exercise, which significantly decreased from 8.9° to 6.5°²⁴⁾. Otman et al. reported that the Schroth exercise showed significant effects not only on Cobb’s angle but also on vital capacity¹⁵⁾. After the Schroth exercise, pain due to scoliosis resolved or improved in 85% of the patients, which helped enhance their quality of life²⁵⁾, and the vital capacity increased in roughly 95% of the patients. The vital capacity increased by at least 600 ml in 22% of the patients after 6 weeks and by 800 ml in 11% of the patients after the same period²⁶⁾. The results of the present study also showed significant effects in the thoracic Cobb’s angle, thoracic trunk rotation angle, and vital capacity after the Schroth exercise. The trunk rotation angle decreased when the acromion of the rib was turned to the opposite side by the 3-dimensional rotational breathing during the Schroth exercise. This 3-dimensional rotational breathing allowed the exercise to become more 3-dimensional, which expanded the narrowed thoracic cage. Furthermore, with the use of the forced inspiratory and the forced expiratory muscles, the angle of scoliosis and pulmonary function decreased simultaneously. Therefore, this study showed that the Schroth exercise, which is a conservative therapy, was effective even for subjects with a 40° or greater Cobb’s angle who need operative treatment. Growing adolescents have a high risk of progress owing to a high degree of scoliosis because they spend much time sitting at school. Therefore, appropriate education, prevention, and improvement of scoliosis are necessary. In addition to this, universal exercises and preventive education need to be more advanced than they are now.

Limitations of this study include the limited number of patients with 40° or greater scoliosis and the difficulty in finding time for the subjects to participate in this study because most were students who had to attend school. In the future, a study comparing the effects with a group among whom the Schroth exercise is combined with orthosis treatment will be necessary.