- Email: [email protected]
Prevalence of adolescent idiopathic scoliosis in Turkey: an epidemiological study
Journal Pre-proof
Prevalence of Adolescent Idiopathic Scoliosis in Turkey: An Epidemiological Study Hurriyet Yılmaz M.D. Prof. Dr. , Coskun Zaterı M.D. Assist. Prof. , Aslihan Kusvuran Ozkan M.D. , Gulseren Kayalar M.D. , Haluk Berk M.D. Prof. Dr. PII: DOI: Reference:
S1529-9430(20)30020-6 https://doi.org/10.1016/j.spinee.2020.01.008 SPINEE 58098
To appear in:
The Spine Journal
Received date: Revised date: Accepted date:
18 September 2019 14 January 2020 15 January 2020
Please cite this article as: Hurriyet Yılmaz M.D. Prof. Dr. , Coskun Zaterı M.D. Assist. Prof. , Aslihan Kusvuran Ozkan M.D. , Gulseren Kayalar M.D. , Haluk Berk M.D. Prof. Dr. , Prevalence of Adolescent Idiopathic Scoliosis in Turkey: An Epidemiological Study, The Spine Journal (2020), doi: https://doi.org/10.1016/j.spinee.2020.01.008
This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. © 2020 Published by Elsevier Inc.
Prevalence of Adolescent Idiopathic Scoliosis in Turkey: An Epidemiological Study
Hurriyet YILMAZ1, Coskun ZATERI2, Aslihan KUSVURAN OZKAN3, Gulseren KAYALAR4, Haluk BERK5 1
Prof. Dr., M.D., Haliç University, School of Health Science, Physiotherapy and Rehabilitation, Istanbul, Turkey. ORCID ID: 0000-0002-7734-806X. 2
Assist. Prof., M.D., Çanakkale Onsekiz Mart University, Faculty of Medicine, PM&R Department, Çanakkale, Turkey. ORCID ID: 0000-0002-7948-5383 3
M.D., Özülkü Medical Center, Adana, Turkey. ORCID ID: 0000-0001-9837-6900.
4
M.D., Memorial Hospital, PM&R Department, Ankara, Turkey. ORCID ID: 0000-0003-2811-2349.
5
Prof. Dr., M.D., Dokuz Eylul University, Faculty of Medicine, Orthopaedics and Traumatology Department, Izmir, Turkey. ORCID ID: 0000-0003-0402-3608.
Funding: This study was partially funded by Turkish Society of Physical Medicine and Rehabilitation (10,000 Turkish Lira). Conflicts of interest: Author Yilmaz H, author Zateri C, author Kusvuran Ozkan A and author Kayalar G are members of Turkish Society of Physical Medicine and Rehabilitation. They have received partial research funding from Turkish Society of Physical Medicine and Rehabilitation (totally 10,000 Turkish Lira). All authors declare no conflicts of interest. Ethics committee approval: The study was approved by local ethics committee (Number: 115; Date: November 02, 2016). Medical personnel, mobile radiological tools, and logistical support needed during fieldwork were provided by the Directorate General for Health Research, Ministry of Health Republic of Turkey. Acknowledgments The authors would like to thank everyone who supported the screening process during this study, whose names are as follows: General Directorate of Health Services of the Ministry of Health of the Republic of Turkey, Abdullah Akünal, Prof. Dr. Alper Cihan, Dr. Rph. Hilal İlbars, Oğuzhan Özkan, Dr. Rıfat Köse, and Spc. Dr. Serra Karakaya; Turkish Society of Physical Medicine and Rehabilitation; Dr. Ahmet Cemal Kaya (Bülent Ecevit University Faculty of Medicine, PM&R Department), Pt. Ahsen Büyükaslan (Universitiy of Health Science, Şişli Hamidiye Etfal Training and Research Hospital. PM&R Department), Assoc. Prof. Aliye Güzelant (Private Reyap Hospital), Pt. Anıl Özüdoğru (Ahi Evran University Physical Therapy and Rehabilitation Vocational School), Assist. Prof. Arzu Dinç (Medipol University Faculty of Medicine, PM&R Department.), Dr. Aslıhan Taraktaş (Universitiy of Health Science, Fatih Sultan Mehmet Training and Research Hospital. PM&R Department), Assist. Prof. Ayhan Aşkın (Katip Çelebi University Faculty of Medicine, PM&R Department), Dr. Aylin Dikici (Universitiy of Health Science Tepecik Training and Research Hospital. PM&R Department), Dr. Aynur Başaran (Private Dr. Arazi Medical Center), Dr. Aynur M. Terzibaşıoğlu (Universitiy of Health Science İstanbul Training and Research Hospital. PM&R Department), Dr. Aysel Gürcan Atçı (Bezmialem Foundation University Faculty of Medicine, PM&R Department), Dr. Aysun Akansel (Universitiy of Health Science İstanbul Training and Research Hospital. PM&R Department), Pt. Ayşe Alparman (Private Romatem PM&R Clinic, İstanbul), Dr. Ayşe Güç (Kayseri Training and Research Hospital. PM&R Department), Prof. Dr. Ayşegül Ketenci (İstanbul University Faculty of Medicine, PM&R Department), Dr. Bahar Çakmak Bozan (Bakırköy Sadi Konuk Training and Research Hospital. PM&R Department), Dr. Berke Aras (Kastamonu Rehabilitation Center), Assist. Prof. Bilge Ekinci (Erzincan Mengücek Gazi Training and Research Hospital. PM&R Department), Dr. Bilge Kesikburun (Dışkapı Training and Research Hospital. PM&R Department), Dr. Börteçine Nurkan Arslan
(Bahçelievler Family Hospital PM&R Department), Prof. Dr. Canan Tıkız (Celal Bayar University Faculty of Medicine, PM&R Department), Dr. Cemal Taşlıgil (Kastamonu Rehabilitation Center), Dr. Cemil Atalay (Universitiy of Health Science İstanbul Training and Research Hospital. PM&R Department), Dr. Cenk Akşit (Private Altın Koza Medical Center, Adana), Dr. Çağlar Karabaş (Kayseri Training and Research Hospital. PM&R Department), Prof. Dr. Dilşad Sindel (İstanbul University Faculty of Medicine, PM&R Department), Pt. Ecem Becerik (Yeditepe University Department of Physiotherapy), Dr. Elmas Kuru (Celal Bayar University Faculty of Medicine, PM&R Department), Assoc. Prof. Emel Ekşioğlu (Dışkapı Training and Research Hospital. PM&R Department), Dr. Emine Eda Kurt (Ahi Evran University Faculty of Medicine, PM&R Department), Dr. Emre Şahin (Dumlupınar University Faculty of Medicine, PM&R Department), Assoc. Prof. Erkan Mesci (Medeniyet University Göztepe Training and Research Hospital. PM&R Department), Dr. Esma Demirhan (Okmeydanı Training and Research Hospital. PM&R Department), Dr. Esma Öcal Eriman (Antakya State Hospital PM&R Department), Pt. Esmanur Kolbaşı, Dr. Esra Özcan (Kastamonu Rehabilition Center), Assoc. Prof. Evrim Coşkun Çelik (Universitiy of Health Science İstanbul Training and Research Hospital. PM&R Department), Dr. Fatih Aksoy (Celal Bayar University Faculty of Medicine, PM&R Department), Dr. Fatih Temiztürk (Dumlupınar University Faculty of Medicine, PM&R Department), Dr. Fatma Aslan (Antakya State Hospital PM&R Clinic), Dr. Fatmanur Aybala Koçak (Ahi Evran University Faculty of Medicine, PM&R Department), Prof. Dr. Figen Yılmaz (Universitiy of Health Science Şişli Hamidiye Etfal Training and Research Hospital. PM&R Department), Dr. Filiz Meryem Sertpoyraz (Universitiy of Health Science Tepecik Training and Research Hospital. PM&R Department), Assist. Prof. Filiz Tuna (Trakya University Faculty of Health Sciences Department of Physiotherapy), Dr. Filiz Yıldız Aydın (Bakırköy Sadi Konuk Training and Research Hospital. PM&R Department), Assoc. Prof. Gül Devrimsel (Recep Tayyip Erdoğan University Faculty of Medicine, PM&R Department), Pt. Gülsen Taşdemir (Gaziantep Municipality İnayet Topçuoğlu Hospital PM&R Department), Dr. Hasan Kara (Selçuk University Faculty of Medicine, PM&R Department), Assoc. Havva Talay Çalış (Kayseri Training and Research Hospital. PM&R Department), Dr. Huriye Esra Göçer (Burdur State Hospital PM&R Clinic), Dr. Hüseyin Işık (Dicle University Faculty of Medicine, PM&R Department), Dr. Işıl Üstün (Bağcılar Training and Research Hospital. PM&R Department), Dr. İdil Kurut Aysin (Katip Çelebi University Atatürk Training and Research Hospital. PM&R Department), Dr. İlhami Ata (Universitiy of Health Science İstanbul Training and Research Hospital. PM&R Department), Assoc. Prof. İlke Coşkun Benlidayı (Çukurova University Medical Faculty, PTR AD.), Assist. Prof. İlker Şengül (Katip Çelebi University Faculty of Medicine, PM&R Department), Dr. İlknur Aykurt Karlıbel (Universitiy of Health Science Yüksek İhtisas Training and Research Hospital. PM&R Department), Pt. İrem Karanki (Haliç University Faculty of Health Sciences Department of Physiotherapy), Prof. Dr. Kadriye Öneş (Universitiy of Health Science İstanbul Training and Research Hospital. PM&R Department), Assoc. Kerem Alptekin (Bahçeşehir University Faculty of Health Sciences Department of Physiotherapy), Pt. Kezban Yaşar (Muş State Hospital, PM&R Clinic), Dr. M. Özge Yıldırım (25 Aralık State Hospital, PM&R Clinic), Dr. Mahmut Kul (Harran University Faculty of Medicine, PM&R Department), Assist. Prof. Meliha Kasapoğlu Aksoy (Universitiy of Health Science Yüksek İhtisas Training and Research Hospital. PM&R Department), Dr. Merve Denizli (Hacettepe University Faculty of Medicine, PM&R Department), Dr. Mualla Biçer (Bakırköy Sadi Konuk Training and Research Hospital. PM&R Department), Dr. Muhsin Doran (Universitiy of Health Science İstanbul Training and Research Hospital. PM&R Department), Dr. Mürüvvet Eroğlu (Ağrı State Hospital PM&R Clinic), Dr. Nihal Tezel (Dışkapı Training and Research Hospital. PM&R Department), Dr. Nihan Erdinç Gündüz (Universitiy of Health Science Tepecik Training and Research Hospital. PM&R Department), Dr. Özlem Aslan Demir (Kırıkhan State Hospital PM&R Clinic), Dr. Özlem Şatır (Antalya Kepez State Hospital PM&R Clinic), Prof. Dr. Pelin Yazgan (Okan University Faculty of Medicine, PM&R Department), Dr. Pınar Akpınar (Universitiy of Health Science Fatih Sultan Mehmet Training and Research Hospital. PM&R Department), Prof. Dr. Pınar Borman (Hacettepe University Faculty of Medicine, PM&R Department), Dr. Pınar Ödevoğlu (Haliç University Faculty of Health Sciences Department of Physiotherapy), Dr. Sefa Tam (Gazi University Faculty of Medicine, PM&R Department), Dr. Seher Kayalı (Private Medova Hospital), Dr. Selda Özçırpıcı (Fulya Acıbadem Hospital PM&R Clinic), Prof. Dr. Selda Sarıkaya (Bülent Ecevit University, Faculty of Medicine, PM&R Department), Assoc. Prof. Serpil Bal (Katip Çelebi University Atatürk Training and Research Hospital. PM&R Department), Dr. Sevgi Atar (Okmeydanı Training and Research Hospital. PM&R Department), Dr. Sinem Bozkurt (Atatürk Training and Research Hospital. PM&R Department), Dr. Şenay Demir Yazıcı (Aydın Atatürk State Hospital PM&R Clinic), Pt. Şeyda Takva, Dr. Tezgül Sezer (Universitiy of Health Science İstanbul Training and Research Hospital. PM&R Department), Dr. Tuğçe El (Çanakkale Onsekiz Mart University Faculty of Medicine), Dr. Turgut Bozan (Dicle University Faculty of Medicine, PM&R Department), Dr. Yasemin Özkan (Dumlupınar University Faculty of Medicine, PM&R Department), Dr. Zeynep Kılıç (Antalya Atatürk State Hospital PM&R Clinic), Dr. Zeynep Sıla Yaşar (Oltu State Hospital PM&R Clinic), and Pt. Zuhal Akman. All names are written in an alphabetical order.
Corresponding author: Coskun Zateri, M.D. Assist. Prof. Department of Physical Medicine and Rehabilitation Canakkale Onsekiz Mart University, Faculty of Medicine 17020 Canakkale, TURKEY Phone: +90 286 2200201 (extension: 3315) Mobile Phone: +90 533 5677462 E-mail: [email protected] ORCID ID: 0000-0002-7948-5383 ResearcherID: A-6278-2016
Prevalence of Adolescent Idiopathic Scoliosis in Turkey: An Epidemiological Study
ABSTRACT
BACKGROUND CONTEXT: Studies have shown that adolescent idiopathic scoliosis (AIS) prevalence varies between 0.35% and 5.2% and it is generally accepted as an average of 2%–3% in children under age 16. There are a few narrow-scope studies based on school screening performed on the epidemiology of AIS in Turkey. Prevalence rates reported by these studies are lower than reported in neighboring countries. Of note, they were conducted in single cities, generally based on small sample size, and are different from each other in terms of methodology and age groups. The current study was conducted based on a large population in 85 schools of 40 provinces in Turkey.
PURPOSE: The aim of this study was to determine the prevalence of AIS in Turkey. Secondary outcomes were to determine age, gender, curve distribution, using standard tests and radiological verification.
STUDY DESIGN: A cross-sectional epidemiological study
PATIENT SAMPLE: The sample size was calculated to estimate the prevalence of AIS in children aged 10-15 years in Turkey.
OUTCOME MEASURES: Adams’ forward bending test, angle of trunk rotation measurement and posture analysis were used to screen. Students who had an angle of trunk rotation greater than or equal to five (≧5°) with scoliometer measurement or who had a positive forward bending test were referred to the mobile X-ray unit located in the school-yard on screening day. Their diagnosis was confirmed using Cobb angles of greater than or equal to ten (≧10°).
METHODS: Medical personnel, mobile radiological tools, and logistical support needed during fieldwork were provided by the Directorate General for Health Research, Ministry of Health Republic of Turkey. Spine and posture were examined in upright standing position. Examiners looked for shoulder asymmetries, scapular prominence, unequal waist, and lower limb length discrepancy. Potential scoliosis diagnosis was verified with onsite radiographic examination. Cases with a Cobb angle of ≧10° detected in any region were accepted as scoliosis. The direction and location of scoliosis were determined according to the Scoliosis Research Society terminology criteria.
RESULTS: A total of 16,045 students were reached whose informed consent forms were signed by their parents. The prevalence of AIS was found to be 2.3% (female, 3.1%; male, 1.5%). Radiological confirmation rate was 98.8%; 256 (69.3%) out of 369 adolescents with scoliosis had a single curvature and 108 (29.3%) had a double curvature. The most common single curve type was a lumbar curve. In all, 90.5% of cases with AIS had a mild (range of 10°–19°) Cobb angle.
CONCLUSIONS: The prevalence of AIS was 2.3% in Turkey. This prevalence rate was considerably higher than the values in previous regional studies conducted in Turkey; however, it was close to generally accepted averages in the literature. One of the strongest aspects of the study was that radiologic confirmation of each suspected case was made during the screening.
Key words: Adolescent idiopathic scoliosis, epidemiology, prevalence, school screening, scoliosis, spine deformity
INTRODUCTION
Adolescent idiopathic scoliosis (AIS) is a three-dimensional structural deformity, which is seen in healthy children of growing age [1,2]. It is unrelated to a specific disease and is defined by the lateral deviation of the spine in the coronal plane more than 10° accompanied by an axial rotation [1,2].
It is possible to overlook mild and moderate scoliosis due to its usual asymptomatic nature. Screening of adolescents in age groups of risk is important for early diagnosis and determining progression. AIS prevalence studies are conducted using school screening methods. Although school screening programs are controversial in the diagnosis of scoliosis due to their difficult evaluation methods and false-positive rate, they are the most effective method in terms of reaching at-risk groups and researching cases, considering the age of emergence of AIS.
Studies have shown that the AIS prevalence varies between 0.35% and 5.2%, and it is generally accepted to have an average of 2%–3% in children under age 16 [3-6]. There have been a few narrow-scope studies based on school screening conducted in single cities in Turkey, generally based on smaller population samples, which are different from each other in terms of methodology and selection of age groups. Yet, according to the results of these studies, AIS prevalence varies between 0.015% and 0.64% in Turkey [7-11]. These prevalence rates are lower than those reported in other countries surrounding Turkey [12-14]. Therefore, they were insufficient for demonstrating the prevalence of AIS in Turkey and for the same reason they do not provide sufficient information.
The aim of this study was to determine the prevalence of AIS in Turkey. Secondary outcomes were to determine age, gender, curve distribution, using standard tests and radiological verification. Consequently, we aimed to establish a reference for the country-specific school-based scoliosis screening program policy.
METHOD
Study design and sampling
A cross-sectional epidemiological study was performed to determine the AIS prevalence in secondary school students aged 10-15 years (grades 5 to 8) in Turkey.
The study was approved by local ethics committee (Number: 115; Date: November 02, 2016). Medical personnel, mobile radiological tools, and logistical support needed during fieldwork were provided by the Directorate General for Health Research, Ministry of Health Republic of Turkey.
Under the coordination of four experts experienced in scoliosis, 83 physicians and 10 physiotherapists participated in the screening. Screening team was informed and trained by the expert physicians about screening methods, posture examination and using the Bunnell scoliometer before the screening.
The families of the adolescents participating in the screening were informed about scoliosis, and their informed consent was obtained.
In the sample calculation, AIS prevalence was accepted as 2% and margin error was 0.3%. Apart from these, the design effect (1.75) and the non-response rate (0.2) were included in the sample calculation.
To determine the sample size of the study, AIS prevalence was empirically set as 2% in accordance to the literature, as there was no previous study that reflects prevalence in Turkey [3-6]. To estimate an expected prevalence of 2%, margin error needs to be a smaller value. Accordingly, margin error was determined to be 0.3% by taking the opinion of the Turkey Institute of Population Studies. The World Health Organization's “Prevalence of Non-communicable Disease Risk Factors in Turkey 2017” report recommends that the design effect should be taken as 1.5% [15]. It is observed that the design effect is taken as 1.5 or 2 in many studies. In the present study, since the prevalence value was taken 2% and the probability of not having any scoliosis in the selected clusters was high, the design effect was determined to be a slightly higher than recommended.
The sample size was calculated as follows:
n0
t 2 * p * (1 - p) * t etk * T * 1 nr ) d2
Where t is 95% confidence interval; p is prevalence; d is sensitivity level (margin error); T is the number of layers (1 for the general population of Turkey); tetk is the design effect; and nr is the nonresponse rate.
In accordance with the aforementioned parameters, the number of samples needed for this study was calculated as 17,570 using the cluster sampling method. As a result of layering with the help of Microsoft Excel and SPSS 20 (IBM Corp., NY, USA), 25,519 adolescents aged 10–15 years were found in the schools of 85 clusters in
different settlements on September 2016 to June 2017. Accordingly, the study was conducted under the name “Turkey AIS - Prevalence Research (TAIS-PR)” in 85 schools (community and private schools) of 40 provinces from January 2017 to June 2017.
Screening
After permission was obtained from Turkey Republic Education Ministry, each school was contacted before the screening program. Information leaflets were sent to all schools and health authorities, and parents. The parents were informed by means of a letter describing the intentions of the study, the clinical importance of early detection, and the details of the examination procedure. Informed consents were obtained from the parents of the students participating in the study. Before the screening, the forms were forwarded to the schools and the children were instructed to fill their biographical information.
Screening was performed during regular lesson time with the assistance of the teachers. All demographic information about the cases (age, height, weight, age, and duration of menarche) were recorded by nurses. Spine and chest deformities, musculoskeletal anomalies, past diseases, and operation history were questioned. The scan was terminated in the presence of a health problem that could affect the spine.
Spine and posture were examined in upright standing position. Shoulder asymmetries, scapular prominence, unequal waist, and lower limb length discrepancy were looked for. Adams’ forward bending test (FBT) and angle of trunk rotation (ATR) by the Bunnell scoliometer (Orthopaedic Systems, Inc., CA, USA) were used for screening. Further, ≧5° was used as ATR cut-off value [16]. Patients with at least one positive test were suspected to have scoliosis and referred to X-Ray examination. Patients with suspected scoliosis underwent a standard spinal posterio-anterior (PA) radiography (36-inch films) of whole spine (from head to pelvis with the inclusion of hip joints and femoral heads) in standing position. X-Ray images were taken on the day of screening using a “Dynamic X-Ray Dynalift 5S” or “DRS Hi-Light 1000 DR” digital X-Ray machine placed in a mobile unit installed at the school-yard.
Radiographic evaluation
Radiographs were evaluated by same investigator (HB), experienced in spinal deformity, who did not participate in the screening. Congenital anomaly was excluded because they might lead to secondary scoliosis. Angle measurements were performed using the standard Cobb method. The Osirix 9.9 program for Mac was used for
measurement. Any curve measured ≧5° was noted, yet only cases with a Cobb angle of ≧10°, detected in any region, were accepted as scoliosis. The direction and location of the scoliosis were determined according to the Scoliosis Research Society terminology criteria [17].
Cobb angle was measured at 82 curves on 60 X-Rays, which were randomly selected in the first stage, to ensure standardization of Cobb angle measurement and reliability. The measurements were repeated 3 weeks later on the same radiographs in randomized order, and the results were compared. Intra-class correlation coefficient (ICC; Bland Altman Statistic) and Kappa values were calculated on the basis of the obtained results. A result of 0.40 was accepted as weak, 0.40–0.59 as medium, 0.60–0.74 as good, and 0.75–1.00 as perfect [18]. In the present study, the ICC value was calculated as 0.97 [95% confidence interval (95% CI) 0.96–0.98] and the intrarater reliability as 0.74 (detecting curve 5° vs. ≧5°).
Data analysis
Statistical analyses were performed with the SPSS 20 package program. Frequency and descriptive statistical methods were used for demographic data and radiological measurement results. The results were given as the percentage value and mean ± standard deviation. The age- and sex-specific prevalence rates were calculated as 95% CI.
RESULTS
Written informed consent was obtained from the parents of 16,347 students. On screening day, a total of 16,045 students were enrolled in the study, of which 7,883 (49.1%) were male and 8,162 (50.9%) were female. This number constituted 91.3% of the 17,570 students, which was the targeted sample size. The flow diagram of the study is given in Figure 1.
The mean age of all screened students was calculated as 12.0±1.3 years (min: 10; max: 15 years). Of the girls, 2,604 (37.3%) had menarche. The mean age of menarche was 12.2±1.0 years. After the screening tests, 2,545 (15.9%) of the 16,045 patients were suspected to have scoliosis and referred for radiography. Of those, 30 suspected cases rejected radiography, thus X-ray evaluation was conducted in 2,515 (98.8%) of the suspected cases.
The curve in 380 of 2515 subjects Cobb angle was measured ≧10° and in 558 cases between 5° and 10°. Eleven cases (2.9%) were excluded due to spinal anomaly (hemivertebrae, block vertebrae, butterfly vertebra, or short legs) which were evaluated as secondary scoliosis.
A total of 369 cases were accepted as AIS, and the prevalence was calculated as 2.3% (95% CI: 2.19-2.41). The prevalence was 1.5% (95% CI: 1.43-1.57) in males and 3.1% (95% CI: 2.95-3.25) in females. The mean age of AIS cases was 12.2±1.3 years, and the BMI was 18.6±3.2 kg/cm2. When the prevalence was evaluated according to mean age and sex, it was 2.7% in girls and 1.3% in boys aged 10 – <12 years, 3.5% in girls and 1.5% in boys aged ≧12 – <14 years, and 3.4% in girls and 2.0% in boys aged ≧14 years. The prevalence increased with age. When we evaluate the prevalence of AIS according to regional distribution, the highest prevalence was observed in central Anatolia (around Ankara Province, Turkey’s Capital) with 3.1%. The lowest prevalence was observed in the Aegean and North-Eastern Anatolia regions with 1.6%.
The demographic characteristics of the cases are given in Table 1, and the prevalence of AIS by Cobb angle and age distribution is given in Table 2. Age distribution of Cobb angles are shown in Figure 2.
In the evaluation made according to the curvature size, the Cobb angle was in the range of 10°–19° in 90.5% of cases with AIS. Large angle curvatures were more frequent in girls (Table 3).
When examining the curve pattern, 256 (69.3%) adolescents had a single curvature, 108 (29.3%) had a double curvature, and 5 (1.4%) had a triple curvature. In the single-curvature group, 27.1% of the curvatures were lumbar, 23% were thoracolumbar, and 16.5% were located in the thoracic region (Table 4).
DISCUSSION
The primary aim of this study was to obtain accurate data about the AIS prevalence in Turkey. This study indicated that the scoliosis prevalence of adolescents aged 10-15 years in Turkey was 2.3%. This result was considerably higher than the rates reported in previous studies conducted in Turkey and similar to the rates reported from other countries [3-14].
This difference probably arose from the high validation rate of suspected scoliosis children in our study. The radiological verification rate in the TAIS-PR study was 98.8%. In previous studies conducted in Turkey, screened subjects with suspected scoliosis were invited to hospitals for radiological verification or a re-
evaluation by a relevant specialist while in TAIS-PR the radiological confirmation was performed same day onsite.
Referral criteria
Adams’ FBT is fast, sensitive, inexpensive, and easily accepted by patients [19]. However, it is a subjective test, does not provide quantitative data, and is insufficient in evaluating minor curvatures, especially in the lumbar region. To increase the accuracy of screening tests it is recommended to use Adams forward bending test and objective trunk rotation measuring together. Reported sensitivity of the FBT and scoliometer tests used in school screening programs was 71.1% and the specificity was 97.1%. The rate of false negativity was 28.9% [20].
Since the main purpose of the present study was to determine scoliosis cases and reveal the most accurate AIS prevalence, both tests were used for screening and the positivity of only one test was enough for a radiological referral. Although, ATR cut-off values range between 4° and 7° in the literature, in our study we decided empirically the most commonly used value of 5° as ATR cut-off value [21,22].
Age-related prevalence, female–male ratio
Our TAIS-PR study revealed AIS prevalence 1.5% in boys and 3.1% in girls, and the male-to-female ratio was 1:2.1. As reported in literatures, this study showed that AIS was more common in girls. The ratio of girls to boys was reported to range between 1:2.3 and 1:18 [13,22,23]. In some studies, AIS prevalence were reported higher in girls in all age groups and higher in the age group 15–16 after puberty in both sexes [5,24]. In the TAIS-PR study, the prevalence of AIS in adolescents aged more than 14 years was higher in both sexes than in other age groups.
Curve type and magnitude
Higher prevalence rate was recorded in between 10° and 19° curves. AIS prevalence decreased with the increase in curve magnitudes. This tendency was observed in both sexes, but the average degree of curvature was still higher in girls than in boys. These results were similar to those in the study by Zheng et al [24].
Types of curvatures and their locations were quite different in school screening studies. Some studies reported more single curvatures, while others showed more double curvatures. Although single curvatures were more often on the left, the left/right ratio of the thoracic, thoracolumbar, and lumbar regions, according to the apex of
the curvature, showed significant differences [22,23,25,26]. In the TAIS-PR study, single curvatures were found to be higher (69.3%), and the curvatures were mostly left sided. Lumbar curvatures were most common (27.1%), followed by thoracolumbar curvatures (23%). In published studies, thoracolumbar curvatures were found more frequently, and lumbar curvatures were reported as second most common.
Radiological validation rates
One of the most important issues of school screening programs conducted for almost 60 years worldwide is the low radiological validation rate despite the high radiological referral rates [7,27,28]. The data on the reported radiological validation rates obtained from the small number of studies ranged from 38% to 74% [27,28].
The radiological verification rate in the TAIS-PR study was 98.8%. To date, this is the highest reported rate of radiological validation. This success of the TAIS-PR study was due to the radiological verification of suspected cases was carried out on the same day on site, as mentioned earlier. Thus, lost cases were prevented, and true prevalence was obtained.
Another strength of our study was that single investigator reviewed all X-Rays. This prevented intra-rater variability, should there be multiple investigators in measuring. In the present study, the ICC value was calculated as 0.97 [95% confidence interval (95% CI) 0.96–0.98] and the intra-rater reliability as 0.74 (detecting curve 5° vs. ≧5°). Obviously, this eliminates the possibility of missing curves ≧10°.
Limitations
Mobile X-Ray devices were used in the TAIS-PR study for radiological verification, thus increasing the costs. It is not possible to recommend the applied method as a routine scoliosis-screening program in point of its costeffectiveness. One of the important limitations of the present study was that the ATR degrees obtained with the scoliometer were not noted, thus, scoliometer measurements and curve magnitudes could not be correlated.
Conclusions
The TAIS-PR study is the most comprehensive study ever conducted in Turkey to date. Radiological validation rate of this study is the highest rate of school-based screening programs reported in the literature until now. The prevalence of AIS in Turkey was similar to that reported in other countries and higher in females. Costeffectiveness analyses are required to determine the value of school screening programs. Since AIS prevalence
increases with age, early diagnosis and treatment is important and the screening should be carried out before the completion of maturation, especially in girls aged 12-14.
REFERENCES
1.
Fadzan M, Bettany-Saltikov J. Etiological theories of adolescent idiopathic scoliosis: past and present. Open Orthop J 2013;29:1466-89. doi: 10.2174/1874325001711011466.
2.
Weinstein SL, Dolan LA, Cheng JC, Danielsson A, Morcuende JA. Adolescent idiopathic scoliosis. Lancet 2008;371:1527-37. doi: 10.1016/S0140-6736(08)60658-3.
3.
Brooks HL, Azen SP, Gerberg E, Brooks R, Chan L. Scoliosis: a prospective epidemiological study. J Bone Joint Surg Am 1975;57:968–72.
4.
Daruwalla JS, Balasubramaniam P, Chay SO, Rajan U, Lee HP. Idiopathic scoliosis. Prevalence and ethnic distribution in Singapore schoolchildren. J Bone Joint Surg Br 1985;67:182–4.
5.
Konieczny MR, Senyurt H, Krauspe R. Epidemiology of adolescent idiopathic scoliosis. J Child Orthop 2013;7:3–9. doi: 10.1007/s11832-012-0457-4.
6.
Hresko MT, Talwalkar V, Schwend R; AAOS, SRS, and POSNA. Early detection of idiopathic scoliosis in adolescents. J Bone Joint Surg Am 2016;98(16):e67. doi: 10.2106/JBJS.16.00224.
7.
Ugras AA, Yılmaz M. Sungur I, Kaya I, Koyuncu Y, Cetinus ME. Prevalence of scoliosis and costeffectiveness of screening in schools in Turkey. J Back Musculoskelet Rehabil 2010;23:1–4. doi: 10.3233/BMR-2010-0247.
8.
Cilli K, Tezeren G, Taş T, Bulut O, Oztürk H, Oztemur Z, et al. School screening for scoliosis in Sivas, Turkey. Acta Orthop Traumatol Turc 2009;43:426-30. doi: 10.3944/AOTT.2009.426.
9.
Yılmaz T, Gökçe A, Naderi S, Yaman O, Dalbayrak S. School screening of adolescent idiopathic scoliosis in 7928 Turkish children. J Turk Spin Surg 2016;3:135-42.
10. Ibisoglu YU, Calis FA, Yagiz On A. Prevalence of scoliosis among primary school children aged 12-14 years living in a town in western Turkey. Turk J Phys Med Rehab 2012;58:109-13. 11. Tezeren G, Ozlu K, Aydemir A, Ayasli A, Kahraman H, Dülgeroglu D. School screening for scoliosis in Ankara. J Turk Spinal Surg 1993;3:92-4. 12. Tanchev P, Dikov D, Dzherov A, Parushev A, Zahariev L, Todorov N, et al. School screening for scoliosis in Sofia: an analysis of screening results of 4800 students. Orthop Trauma 1996;33:69–73.
13. Grivas TB, Koukos K, Koukou UI, Maziotou C, Polyzois BD. The incidence of idiopathic scoliosis in Greece-analysis of domestic school screening programs. Stud Health Technol Inform 2002;91:71-5. 14. Koukourakis I, Giaourakis G, Kouvidis G, Kivernitakis E, Blazos J, Koukourakis M. Screening school children for scoliosis on the island of Crete. J Spinal Disord 1997;10:527-31. 15. National Household Health Survey – Prevalence of Noncommunicable Disease Risk Factors in Turkey 2017 (STEPS). Üner S, Balcılar M, Ergüder T editors. World Health Organization Country Office in Turkey, Ankara, 2018. 16. Bunnell WP. Outcome of Spinal Screening. Spine 1993;18:1572-80. 17. https://www.srs.org/professionals/online-education-and-resources/glossary/revised-glossary-ofterms.(Access: 02 May 2019). 18. McHugh ML. Interrater reliability: the kappa statistic. Biochem Med (Zagreb) 2012;22(3):276-282. 19. Bunnell WP. Selective screening for scoliosis. Clin Orthop Relat Res 2005;434:40-5. 20. Dunn J, Henrikson NB, Morrison CC, Nguyen M, Blasi PR, Lin JS. Screening for adolescent idiopathic scoliosis: a systematic evidence review for the U.S. Preventive Services Task Force. Evidence Synthesis No. 156. AHRQ Publication No. 17-05230-EF-1. Rockville, MD: Agency for Healthcare Research and Quality 2018. PMID: 29638297. 21. Lee CF, Fong DY, Cheung KM, Cheng JC, Ng BK, Lam TP, et al. Referral criteria for scoliosis screening: assessment and recommendations based on a large longitudinally followed cohort. Spine 2010;35:1492-8. doi: 10.1097/BRS.0b013e3181ecf3fe. 22. Lee JY, Moon SH, Kim HJ, Park MS, Suh BK, Nam JH, et al. The prevalence of idiopathic scoliosis in eleven year-old Korean adolescents: a 3 year epidemiological study. Yonsei Med J 2014;55:773-8. doi: 10.3349/ymj.2014.55.3.773. 23. Ueno M, Takaso M, Nakazawa T, Imura T, Saito W, Shintani R, et al. A 5-year epidemiological study on the prevalence rate of idiopathic scoliosis in Tokyo: School screening of more than 250.000 children. J Orthop Sci 2011;16:1-6. doi: 10.1007/s00776-010-0009-z. 24. Zheng Y, Dang Y, Wu X, Yang Y, Reinhardt JD, He C, et al. Epidemiological study of adolescent idiopathic scoliosis in Eastern China. J Rehabil Med 201749:512-9. doi: 10.2340/16501977-2240. 25. Soucacos PN, Soucacos PK, Zacharis KC, Beris AE, Xenakis TA. School-screening for scoliosis: a prospective epidemiological study in Northwestern and central Greece. J Bone Joint Surg Am 1997;79:1498-503.
26. Wong HK, Hui JH, Rajan U, Chia HP. Idiopathic scoliosis in Singapore schoolchildren: a prevalence study 15 years into the screening program. Spine 2015;30:1188-96. 27. Deepak AS, Ong JY, Choon D, Lee CK, Chiu CK, Chan C, et al. The clinical effectiveness of school screening program for idiopathic scoliosis in Malaysia. Malays Orthop J 2017;11:41-6. doi: 10.5704/MOJ.1703.018. 28. Altaf F, Drinkwater J, Phan K, Cree AK. Systematic review of school scoliosis screening. Spine Deform 2017;5:303-9. doi: 10.1016/j.jspd.2017.03.009.
Figure 1. Flow diagram of the study
Figure 2. Box plot and whisker chart showing median (central dark line) Quartiles 1 and 3 as well as minimum and maximum values as per age groups for Cobb angles greater than or equal to 10°.
Table 1. Demographic characteristics of the cases
All cases
Number of cases (%) Mean age (years) ± SD Mean BMI (kg/m2) ± SD Menarche (n (%))
AIS
Female
Male
Female
Male
Total
8162 (50.9%)
7883 (49.1%)
251
118
369
12 ± 1.2
12.1 ± 1.3
12.2 ± 1.4
12.2 ± 1.45
12.2±1.3
19.3 ± 3.8
19.3 ± 3.8
18.7 ± 2.9
18.6 ± 3.6
18.6 ± 3.2
14.1° ± 4.6°
14.6° ± 5.2°
2604 (37.3%)
94 (41.6%)
12.2 ± 1.0
12.3 ± 1.1
Mean age of menarche (months) ± SD Cobb angle, mean ± SD
14.8° ± 5.4°
AIS: Adolescent idiopathic scoliosis, BMI: Body mass index, SD: Standard Deviation,
Table 2. Prevalence of adolescent idiopathic scoliosis by Cobb angle and age distribution
Minor curve (<10o Cobb angle) prevalence
Female
Male
Total
Cobb angle ≧5°
7.1
4.4
5.8
Cobb angle ≧5° – <10°
4.0
2.9
3.5
in all age
3.1
1.5
2.3
≧10 – <12 age
2.7
1.3
2.0
≧12 – <14 age
3.5
1.5
2.5
≧14 age
3.4
2.0
2.7
AIS prevalence according to age distribution
AIS: Adolescent idiopathic scoliosis
Table 3. Distribution of Cobb angles in adolescent idiopathic scoliosis cases
Number of idiopathic scoliosis cases in adolescents Cobb angle Male (n)
%
Female (n)
%
Total (n)
%
M/F ratio
10°–19°
108
29.2
226
61.3
334
90.5
1:2.1
20°–29°
8
2.2
18
4.8
26
7.0
1:2.3
30°–39°
1
0.3
5
1.4
6
1.7
1:5.0
≧40°
1
0.3
2
0.5
3
0.8
1:2.0
Total
118
32.0
251
68.0
369
100.0
1:2.1
M: male, F: female
Table 4. Scoliosis location distribution and curvature types
Convexity Scoliosis pattern Right
Left
Total (%)
102
154
256 (69.3)
Cervical
0
1
1 (0.3)
Cervicothoracic
0
9
9 (2.4)
Thoracic
41
20
61 (16.5)
Thoracolumbar
35
50
85 (23.0)
Lumbar
26
74
100 (27.1)
Single curvature
Double curvature
108 (29.3)
Triple curvature
5 (1.4)
Total
369 (100)
Prevalence of Adolescent Idiopathic Scoliosis in Turkey: An Epidemiological Study Hurriyet Yılmaz M.D. Prof. Dr. , Coskun Zaterı M.D. Assist. Prof. , Aslihan Kusvuran Ozkan M.D. , Gulseren Kayalar M.D. , Haluk Berk M.D. Prof. Dr. PII: DOI: Reference:
S1529-9430(20)30020-6 https://doi.org/10.1016/j.spinee.2020.01.008 SPINEE 58098
To appear in:
The Spine Journal
Received date: Revised date: Accepted date:
18 September 2019 14 January 2020 15 January 2020
Please cite this article as: Hurriyet Yılmaz M.D. Prof. Dr. , Coskun Zaterı M.D. Assist. Prof. , Aslihan Kusvuran Ozkan M.D. , Gulseren Kayalar M.D. , Haluk Berk M.D. Prof. Dr. , Prevalence of Adolescent Idiopathic Scoliosis in Turkey: An Epidemiological Study, The Spine Journal (2020), doi: https://doi.org/10.1016/j.spinee.2020.01.008
This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. © 2020 Published by Elsevier Inc.
Prevalence of Adolescent Idiopathic Scoliosis in Turkey: An Epidemiological Study
Hurriyet YILMAZ1, Coskun ZATERI2, Aslihan KUSVURAN OZKAN3, Gulseren KAYALAR4, Haluk BERK5 1
Prof. Dr., M.D., Haliç University, School of Health Science, Physiotherapy and Rehabilitation, Istanbul, Turkey. ORCID ID: 0000-0002-7734-806X. 2
Assist. Prof., M.D., Çanakkale Onsekiz Mart University, Faculty of Medicine, PM&R Department, Çanakkale, Turkey. ORCID ID: 0000-0002-7948-5383 3
M.D., Özülkü Medical Center, Adana, Turkey. ORCID ID: 0000-0001-9837-6900.
4
M.D., Memorial Hospital, PM&R Department, Ankara, Turkey. ORCID ID: 0000-0003-2811-2349.
5
Prof. Dr., M.D., Dokuz Eylul University, Faculty of Medicine, Orthopaedics and Traumatology Department, Izmir, Turkey. ORCID ID: 0000-0003-0402-3608.
Funding: This study was partially funded by Turkish Society of Physical Medicine and Rehabilitation (10,000 Turkish Lira). Conflicts of interest: Author Yilmaz H, author Zateri C, author Kusvuran Ozkan A and author Kayalar G are members of Turkish Society of Physical Medicine and Rehabilitation. They have received partial research funding from Turkish Society of Physical Medicine and Rehabilitation (totally 10,000 Turkish Lira). All authors declare no conflicts of interest. Ethics committee approval: The study was approved by local ethics committee (Number: 115; Date: November 02, 2016). Medical personnel, mobile radiological tools, and logistical support needed during fieldwork were provided by the Directorate General for Health Research, Ministry of Health Republic of Turkey. Acknowledgments The authors would like to thank everyone who supported the screening process during this study, whose names are as follows: General Directorate of Health Services of the Ministry of Health of the Republic of Turkey, Abdullah Akünal, Prof. Dr. Alper Cihan, Dr. Rph. Hilal İlbars, Oğuzhan Özkan, Dr. Rıfat Köse, and Spc. Dr. Serra Karakaya; Turkish Society of Physical Medicine and Rehabilitation; Dr. Ahmet Cemal Kaya (Bülent Ecevit University Faculty of Medicine, PM&R Department), Pt. Ahsen Büyükaslan (Universitiy of Health Science, Şişli Hamidiye Etfal Training and Research Hospital. PM&R Department), Assoc. Prof. Aliye Güzelant (Private Reyap Hospital), Pt. Anıl Özüdoğru (Ahi Evran University Physical Therapy and Rehabilitation Vocational School), Assist. Prof. Arzu Dinç (Medipol University Faculty of Medicine, PM&R Department.), Dr. Aslıhan Taraktaş (Universitiy of Health Science, Fatih Sultan Mehmet Training and Research Hospital. PM&R Department), Assist. Prof. Ayhan Aşkın (Katip Çelebi University Faculty of Medicine, PM&R Department), Dr. Aylin Dikici (Universitiy of Health Science Tepecik Training and Research Hospital. PM&R Department), Dr. Aynur Başaran (Private Dr. Arazi Medical Center), Dr. Aynur M. Terzibaşıoğlu (Universitiy of Health Science İstanbul Training and Research Hospital. PM&R Department), Dr. Aysel Gürcan Atçı (Bezmialem Foundation University Faculty of Medicine, PM&R Department), Dr. Aysun Akansel (Universitiy of Health Science İstanbul Training and Research Hospital. PM&R Department), Pt. Ayşe Alparman (Private Romatem PM&R Clinic, İstanbul), Dr. Ayşe Güç (Kayseri Training and Research Hospital. PM&R Department), Prof. Dr. Ayşegül Ketenci (İstanbul University Faculty of Medicine, PM&R Department), Dr. Bahar Çakmak Bozan (Bakırköy Sadi Konuk Training and Research Hospital. PM&R Department), Dr. Berke Aras (Kastamonu Rehabilitation Center), Assist. Prof. Bilge Ekinci (Erzincan Mengücek Gazi Training and Research Hospital. PM&R Department), Dr. Bilge Kesikburun (Dışkapı Training and Research Hospital. PM&R Department), Dr. Börteçine Nurkan Arslan
(Bahçelievler Family Hospital PM&R Department), Prof. Dr. Canan Tıkız (Celal Bayar University Faculty of Medicine, PM&R Department), Dr. Cemal Taşlıgil (Kastamonu Rehabilitation Center), Dr. Cemil Atalay (Universitiy of Health Science İstanbul Training and Research Hospital. PM&R Department), Dr. Cenk Akşit (Private Altın Koza Medical Center, Adana), Dr. Çağlar Karabaş (Kayseri Training and Research Hospital. PM&R Department), Prof. Dr. Dilşad Sindel (İstanbul University Faculty of Medicine, PM&R Department), Pt. Ecem Becerik (Yeditepe University Department of Physiotherapy), Dr. Elmas Kuru (Celal Bayar University Faculty of Medicine, PM&R Department), Assoc. Prof. Emel Ekşioğlu (Dışkapı Training and Research Hospital. PM&R Department), Dr. Emine Eda Kurt (Ahi Evran University Faculty of Medicine, PM&R Department), Dr. Emre Şahin (Dumlupınar University Faculty of Medicine, PM&R Department), Assoc. Prof. Erkan Mesci (Medeniyet University Göztepe Training and Research Hospital. PM&R Department), Dr. Esma Demirhan (Okmeydanı Training and Research Hospital. PM&R Department), Dr. Esma Öcal Eriman (Antakya State Hospital PM&R Department), Pt. Esmanur Kolbaşı, Dr. Esra Özcan (Kastamonu Rehabilition Center), Assoc. Prof. Evrim Coşkun Çelik (Universitiy of Health Science İstanbul Training and Research Hospital. PM&R Department), Dr. Fatih Aksoy (Celal Bayar University Faculty of Medicine, PM&R Department), Dr. Fatih Temiztürk (Dumlupınar University Faculty of Medicine, PM&R Department), Dr. Fatma Aslan (Antakya State Hospital PM&R Clinic), Dr. Fatmanur Aybala Koçak (Ahi Evran University Faculty of Medicine, PM&R Department), Prof. Dr. Figen Yılmaz (Universitiy of Health Science Şişli Hamidiye Etfal Training and Research Hospital. PM&R Department), Dr. Filiz Meryem Sertpoyraz (Universitiy of Health Science Tepecik Training and Research Hospital. PM&R Department), Assist. Prof. Filiz Tuna (Trakya University Faculty of Health Sciences Department of Physiotherapy), Dr. Filiz Yıldız Aydın (Bakırköy Sadi Konuk Training and Research Hospital. PM&R Department), Assoc. Prof. Gül Devrimsel (Recep Tayyip Erdoğan University Faculty of Medicine, PM&R Department), Pt. Gülsen Taşdemir (Gaziantep Municipality İnayet Topçuoğlu Hospital PM&R Department), Dr. Hasan Kara (Selçuk University Faculty of Medicine, PM&R Department), Assoc. Havva Talay Çalış (Kayseri Training and Research Hospital. PM&R Department), Dr. Huriye Esra Göçer (Burdur State Hospital PM&R Clinic), Dr. Hüseyin Işık (Dicle University Faculty of Medicine, PM&R Department), Dr. Işıl Üstün (Bağcılar Training and Research Hospital. PM&R Department), Dr. İdil Kurut Aysin (Katip Çelebi University Atatürk Training and Research Hospital. PM&R Department), Dr. İlhami Ata (Universitiy of Health Science İstanbul Training and Research Hospital. PM&R Department), Assoc. Prof. İlke Coşkun Benlidayı (Çukurova University Medical Faculty, PTR AD.), Assist. Prof. İlker Şengül (Katip Çelebi University Faculty of Medicine, PM&R Department), Dr. İlknur Aykurt Karlıbel (Universitiy of Health Science Yüksek İhtisas Training and Research Hospital. PM&R Department), Pt. İrem Karanki (Haliç University Faculty of Health Sciences Department of Physiotherapy), Prof. Dr. Kadriye Öneş (Universitiy of Health Science İstanbul Training and Research Hospital. PM&R Department), Assoc. Kerem Alptekin (Bahçeşehir University Faculty of Health Sciences Department of Physiotherapy), Pt. Kezban Yaşar (Muş State Hospital, PM&R Clinic), Dr. M. Özge Yıldırım (25 Aralık State Hospital, PM&R Clinic), Dr. Mahmut Kul (Harran University Faculty of Medicine, PM&R Department), Assist. Prof. Meliha Kasapoğlu Aksoy (Universitiy of Health Science Yüksek İhtisas Training and Research Hospital. PM&R Department), Dr. Merve Denizli (Hacettepe University Faculty of Medicine, PM&R Department), Dr. Mualla Biçer (Bakırköy Sadi Konuk Training and Research Hospital. PM&R Department), Dr. Muhsin Doran (Universitiy of Health Science İstanbul Training and Research Hospital. PM&R Department), Dr. Mürüvvet Eroğlu (Ağrı State Hospital PM&R Clinic), Dr. Nihal Tezel (Dışkapı Training and Research Hospital. PM&R Department), Dr. Nihan Erdinç Gündüz (Universitiy of Health Science Tepecik Training and Research Hospital. PM&R Department), Dr. Özlem Aslan Demir (Kırıkhan State Hospital PM&R Clinic), Dr. Özlem Şatır (Antalya Kepez State Hospital PM&R Clinic), Prof. Dr. Pelin Yazgan (Okan University Faculty of Medicine, PM&R Department), Dr. Pınar Akpınar (Universitiy of Health Science Fatih Sultan Mehmet Training and Research Hospital. PM&R Department), Prof. Dr. Pınar Borman (Hacettepe University Faculty of Medicine, PM&R Department), Dr. Pınar Ödevoğlu (Haliç University Faculty of Health Sciences Department of Physiotherapy), Dr. Sefa Tam (Gazi University Faculty of Medicine, PM&R Department), Dr. Seher Kayalı (Private Medova Hospital), Dr. Selda Özçırpıcı (Fulya Acıbadem Hospital PM&R Clinic), Prof. Dr. Selda Sarıkaya (Bülent Ecevit University, Faculty of Medicine, PM&R Department), Assoc. Prof. Serpil Bal (Katip Çelebi University Atatürk Training and Research Hospital. PM&R Department), Dr. Sevgi Atar (Okmeydanı Training and Research Hospital. PM&R Department), Dr. Sinem Bozkurt (Atatürk Training and Research Hospital. PM&R Department), Dr. Şenay Demir Yazıcı (Aydın Atatürk State Hospital PM&R Clinic), Pt. Şeyda Takva, Dr. Tezgül Sezer (Universitiy of Health Science İstanbul Training and Research Hospital. PM&R Department), Dr. Tuğçe El (Çanakkale Onsekiz Mart University Faculty of Medicine), Dr. Turgut Bozan (Dicle University Faculty of Medicine, PM&R Department), Dr. Yasemin Özkan (Dumlupınar University Faculty of Medicine, PM&R Department), Dr. Zeynep Kılıç (Antalya Atatürk State Hospital PM&R Clinic), Dr. Zeynep Sıla Yaşar (Oltu State Hospital PM&R Clinic), and Pt. Zuhal Akman. All names are written in an alphabetical order.
Corresponding author: Coskun Zateri, M.D. Assist. Prof. Department of Physical Medicine and Rehabilitation Canakkale Onsekiz Mart University, Faculty of Medicine 17020 Canakkale, TURKEY Phone: +90 286 2200201 (extension: 3315) Mobile Phone: +90 533 5677462 E-mail: [email protected] ORCID ID: 0000-0002-7948-5383 ResearcherID: A-6278-2016
Prevalence of Adolescent Idiopathic Scoliosis in Turkey: An Epidemiological Study
ABSTRACT
BACKGROUND CONTEXT: Studies have shown that adolescent idiopathic scoliosis (AIS) prevalence varies between 0.35% and 5.2% and it is generally accepted as an average of 2%–3% in children under age 16. There are a few narrow-scope studies based on school screening performed on the epidemiology of AIS in Turkey. Prevalence rates reported by these studies are lower than reported in neighboring countries. Of note, they were conducted in single cities, generally based on small sample size, and are different from each other in terms of methodology and age groups. The current study was conducted based on a large population in 85 schools of 40 provinces in Turkey.
PURPOSE: The aim of this study was to determine the prevalence of AIS in Turkey. Secondary outcomes were to determine age, gender, curve distribution, using standard tests and radiological verification.
STUDY DESIGN: A cross-sectional epidemiological study
PATIENT SAMPLE: The sample size was calculated to estimate the prevalence of AIS in children aged 10-15 years in Turkey.
OUTCOME MEASURES: Adams’ forward bending test, angle of trunk rotation measurement and posture analysis were used to screen. Students who had an angle of trunk rotation greater than or equal to five (≧5°) with scoliometer measurement or who had a positive forward bending test were referred to the mobile X-ray unit located in the school-yard on screening day. Their diagnosis was confirmed using Cobb angles of greater than or equal to ten (≧10°).
METHODS: Medical personnel, mobile radiological tools, and logistical support needed during fieldwork were provided by the Directorate General for Health Research, Ministry of Health Republic of Turkey. Spine and posture were examined in upright standing position. Examiners looked for shoulder asymmetries, scapular prominence, unequal waist, and lower limb length discrepancy. Potential scoliosis diagnosis was verified with onsite radiographic examination. Cases with a Cobb angle of ≧10° detected in any region were accepted as scoliosis. The direction and location of scoliosis were determined according to the Scoliosis Research Society terminology criteria.
RESULTS: A total of 16,045 students were reached whose informed consent forms were signed by their parents. The prevalence of AIS was found to be 2.3% (female, 3.1%; male, 1.5%). Radiological confirmation rate was 98.8%; 256 (69.3%) out of 369 adolescents with scoliosis had a single curvature and 108 (29.3%) had a double curvature. The most common single curve type was a lumbar curve. In all, 90.5% of cases with AIS had a mild (range of 10°–19°) Cobb angle.
CONCLUSIONS: The prevalence of AIS was 2.3% in Turkey. This prevalence rate was considerably higher than the values in previous regional studies conducted in Turkey; however, it was close to generally accepted averages in the literature. One of the strongest aspects of the study was that radiologic confirmation of each suspected case was made during the screening.
Key words: Adolescent idiopathic scoliosis, epidemiology, prevalence, school screening, scoliosis, spine deformity
INTRODUCTION
Adolescent idiopathic scoliosis (AIS) is a three-dimensional structural deformity, which is seen in healthy children of growing age [1,2]. It is unrelated to a specific disease and is defined by the lateral deviation of the spine in the coronal plane more than 10° accompanied by an axial rotation [1,2].
It is possible to overlook mild and moderate scoliosis due to its usual asymptomatic nature. Screening of adolescents in age groups of risk is important for early diagnosis and determining progression. AIS prevalence studies are conducted using school screening methods. Although school screening programs are controversial in the diagnosis of scoliosis due to their difficult evaluation methods and false-positive rate, they are the most effective method in terms of reaching at-risk groups and researching cases, considering the age of emergence of AIS.
Studies have shown that the AIS prevalence varies between 0.35% and 5.2%, and it is generally accepted to have an average of 2%–3% in children under age 16 [3-6]. There have been a few narrow-scope studies based on school screening conducted in single cities in Turkey, generally based on smaller population samples, which are different from each other in terms of methodology and selection of age groups. Yet, according to the results of these studies, AIS prevalence varies between 0.015% and 0.64% in Turkey [7-11]. These prevalence rates are lower than those reported in other countries surrounding Turkey [12-14]. Therefore, they were insufficient for demonstrating the prevalence of AIS in Turkey and for the same reason they do not provide sufficient information.
The aim of this study was to determine the prevalence of AIS in Turkey. Secondary outcomes were to determine age, gender, curve distribution, using standard tests and radiological verification. Consequently, we aimed to establish a reference for the country-specific school-based scoliosis screening program policy.
METHOD
Study design and sampling
A cross-sectional epidemiological study was performed to determine the AIS prevalence in secondary school students aged 10-15 years (grades 5 to 8) in Turkey.
The study was approved by local ethics committee (Number: 115; Date: November 02, 2016). Medical personnel, mobile radiological tools, and logistical support needed during fieldwork were provided by the Directorate General for Health Research, Ministry of Health Republic of Turkey.
Under the coordination of four experts experienced in scoliosis, 83 physicians and 10 physiotherapists participated in the screening. Screening team was informed and trained by the expert physicians about screening methods, posture examination and using the Bunnell scoliometer before the screening.
The families of the adolescents participating in the screening were informed about scoliosis, and their informed consent was obtained.
In the sample calculation, AIS prevalence was accepted as 2% and margin error was 0.3%. Apart from these, the design effect (1.75) and the non-response rate (0.2) were included in the sample calculation.
To determine the sample size of the study, AIS prevalence was empirically set as 2% in accordance to the literature, as there was no previous study that reflects prevalence in Turkey [3-6]. To estimate an expected prevalence of 2%, margin error needs to be a smaller value. Accordingly, margin error was determined to be 0.3% by taking the opinion of the Turkey Institute of Population Studies. The World Health Organization's “Prevalence of Non-communicable Disease Risk Factors in Turkey 2017” report recommends that the design effect should be taken as 1.5% [15]. It is observed that the design effect is taken as 1.5 or 2 in many studies. In the present study, since the prevalence value was taken 2% and the probability of not having any scoliosis in the selected clusters was high, the design effect was determined to be a slightly higher than recommended.
The sample size was calculated as follows:
n0
t 2 * p * (1 - p) * t etk * T * 1 nr ) d2
Where t is 95% confidence interval; p is prevalence; d is sensitivity level (margin error); T is the number of layers (1 for the general population of Turkey); tetk is the design effect; and nr is the nonresponse rate.
In accordance with the aforementioned parameters, the number of samples needed for this study was calculated as 17,570 using the cluster sampling method. As a result of layering with the help of Microsoft Excel and SPSS 20 (IBM Corp., NY, USA), 25,519 adolescents aged 10–15 years were found in the schools of 85 clusters in
different settlements on September 2016 to June 2017. Accordingly, the study was conducted under the name “Turkey AIS - Prevalence Research (TAIS-PR)” in 85 schools (community and private schools) of 40 provinces from January 2017 to June 2017.
Screening
After permission was obtained from Turkey Republic Education Ministry, each school was contacted before the screening program. Information leaflets were sent to all schools and health authorities, and parents. The parents were informed by means of a letter describing the intentions of the study, the clinical importance of early detection, and the details of the examination procedure. Informed consents were obtained from the parents of the students participating in the study. Before the screening, the forms were forwarded to the schools and the children were instructed to fill their biographical information.
Screening was performed during regular lesson time with the assistance of the teachers. All demographic information about the cases (age, height, weight, age, and duration of menarche) were recorded by nurses. Spine and chest deformities, musculoskeletal anomalies, past diseases, and operation history were questioned. The scan was terminated in the presence of a health problem that could affect the spine.
Spine and posture were examined in upright standing position. Shoulder asymmetries, scapular prominence, unequal waist, and lower limb length discrepancy were looked for. Adams’ forward bending test (FBT) and angle of trunk rotation (ATR) by the Bunnell scoliometer (Orthopaedic Systems, Inc., CA, USA) were used for screening. Further, ≧5° was used as ATR cut-off value [16]. Patients with at least one positive test were suspected to have scoliosis and referred to X-Ray examination. Patients with suspected scoliosis underwent a standard spinal posterio-anterior (PA) radiography (36-inch films) of whole spine (from head to pelvis with the inclusion of hip joints and femoral heads) in standing position. X-Ray images were taken on the day of screening using a “Dynamic X-Ray Dynalift 5S” or “DRS Hi-Light 1000 DR” digital X-Ray machine placed in a mobile unit installed at the school-yard.
Radiographic evaluation
Radiographs were evaluated by same investigator (HB), experienced in spinal deformity, who did not participate in the screening. Congenital anomaly was excluded because they might lead to secondary scoliosis. Angle measurements were performed using the standard Cobb method. The Osirix 9.9 program for Mac was used for
measurement. Any curve measured ≧5° was noted, yet only cases with a Cobb angle of ≧10°, detected in any region, were accepted as scoliosis. The direction and location of the scoliosis were determined according to the Scoliosis Research Society terminology criteria [17].
Cobb angle was measured at 82 curves on 60 X-Rays, which were randomly selected in the first stage, to ensure standardization of Cobb angle measurement and reliability. The measurements were repeated 3 weeks later on the same radiographs in randomized order, and the results were compared. Intra-class correlation coefficient (ICC; Bland Altman Statistic) and Kappa values were calculated on the basis of the obtained results. A result of 0.40 was accepted as weak, 0.40–0.59 as medium, 0.60–0.74 as good, and 0.75–1.00 as perfect [18]. In the present study, the ICC value was calculated as 0.97 [95% confidence interval (95% CI) 0.96–0.98] and the intrarater reliability as 0.74 (detecting curve 5° vs. ≧5°).
Data analysis
Statistical analyses were performed with the SPSS 20 package program. Frequency and descriptive statistical methods were used for demographic data and radiological measurement results. The results were given as the percentage value and mean ± standard deviation. The age- and sex-specific prevalence rates were calculated as 95% CI.
RESULTS
Written informed consent was obtained from the parents of 16,347 students. On screening day, a total of 16,045 students were enrolled in the study, of which 7,883 (49.1%) were male and 8,162 (50.9%) were female. This number constituted 91.3% of the 17,570 students, which was the targeted sample size. The flow diagram of the study is given in Figure 1.
The mean age of all screened students was calculated as 12.0±1.3 years (min: 10; max: 15 years). Of the girls, 2,604 (37.3%) had menarche. The mean age of menarche was 12.2±1.0 years. After the screening tests, 2,545 (15.9%) of the 16,045 patients were suspected to have scoliosis and referred for radiography. Of those, 30 suspected cases rejected radiography, thus X-ray evaluation was conducted in 2,515 (98.8%) of the suspected cases.
The curve in 380 of 2515 subjects Cobb angle was measured ≧10° and in 558 cases between 5° and 10°. Eleven cases (2.9%) were excluded due to spinal anomaly (hemivertebrae, block vertebrae, butterfly vertebra, or short legs) which were evaluated as secondary scoliosis.
A total of 369 cases were accepted as AIS, and the prevalence was calculated as 2.3% (95% CI: 2.19-2.41). The prevalence was 1.5% (95% CI: 1.43-1.57) in males and 3.1% (95% CI: 2.95-3.25) in females. The mean age of AIS cases was 12.2±1.3 years, and the BMI was 18.6±3.2 kg/cm2. When the prevalence was evaluated according to mean age and sex, it was 2.7% in girls and 1.3% in boys aged 10 – <12 years, 3.5% in girls and 1.5% in boys aged ≧12 – <14 years, and 3.4% in girls and 2.0% in boys aged ≧14 years. The prevalence increased with age. When we evaluate the prevalence of AIS according to regional distribution, the highest prevalence was observed in central Anatolia (around Ankara Province, Turkey’s Capital) with 3.1%. The lowest prevalence was observed in the Aegean and North-Eastern Anatolia regions with 1.6%.
The demographic characteristics of the cases are given in Table 1, and the prevalence of AIS by Cobb angle and age distribution is given in Table 2. Age distribution of Cobb angles are shown in Figure 2.
In the evaluation made according to the curvature size, the Cobb angle was in the range of 10°–19° in 90.5% of cases with AIS. Large angle curvatures were more frequent in girls (Table 3).
When examining the curve pattern, 256 (69.3%) adolescents had a single curvature, 108 (29.3%) had a double curvature, and 5 (1.4%) had a triple curvature. In the single-curvature group, 27.1% of the curvatures were lumbar, 23% were thoracolumbar, and 16.5% were located in the thoracic region (Table 4).
DISCUSSION
The primary aim of this study was to obtain accurate data about the AIS prevalence in Turkey. This study indicated that the scoliosis prevalence of adolescents aged 10-15 years in Turkey was 2.3%. This result was considerably higher than the rates reported in previous studies conducted in Turkey and similar to the rates reported from other countries [3-14].
This difference probably arose from the high validation rate of suspected scoliosis children in our study. The radiological verification rate in the TAIS-PR study was 98.8%. In previous studies conducted in Turkey, screened subjects with suspected scoliosis were invited to hospitals for radiological verification or a re-
evaluation by a relevant specialist while in TAIS-PR the radiological confirmation was performed same day onsite.
Referral criteria
Adams’ FBT is fast, sensitive, inexpensive, and easily accepted by patients [19]. However, it is a subjective test, does not provide quantitative data, and is insufficient in evaluating minor curvatures, especially in the lumbar region. To increase the accuracy of screening tests it is recommended to use Adams forward bending test and objective trunk rotation measuring together. Reported sensitivity of the FBT and scoliometer tests used in school screening programs was 71.1% and the specificity was 97.1%. The rate of false negativity was 28.9% [20].
Since the main purpose of the present study was to determine scoliosis cases and reveal the most accurate AIS prevalence, both tests were used for screening and the positivity of only one test was enough for a radiological referral. Although, ATR cut-off values range between 4° and 7° in the literature, in our study we decided empirically the most commonly used value of 5° as ATR cut-off value [21,22].
Age-related prevalence, female–male ratio
Our TAIS-PR study revealed AIS prevalence 1.5% in boys and 3.1% in girls, and the male-to-female ratio was 1:2.1. As reported in literatures, this study showed that AIS was more common in girls. The ratio of girls to boys was reported to range between 1:2.3 and 1:18 [13,22,23]. In some studies, AIS prevalence were reported higher in girls in all age groups and higher in the age group 15–16 after puberty in both sexes [5,24]. In the TAIS-PR study, the prevalence of AIS in adolescents aged more than 14 years was higher in both sexes than in other age groups.
Curve type and magnitude
Higher prevalence rate was recorded in between 10° and 19° curves. AIS prevalence decreased with the increase in curve magnitudes. This tendency was observed in both sexes, but the average degree of curvature was still higher in girls than in boys. These results were similar to those in the study by Zheng et al [24].
Types of curvatures and their locations were quite different in school screening studies. Some studies reported more single curvatures, while others showed more double curvatures. Although single curvatures were more often on the left, the left/right ratio of the thoracic, thoracolumbar, and lumbar regions, according to the apex of
the curvature, showed significant differences [22,23,25,26]. In the TAIS-PR study, single curvatures were found to be higher (69.3%), and the curvatures were mostly left sided. Lumbar curvatures were most common (27.1%), followed by thoracolumbar curvatures (23%). In published studies, thoracolumbar curvatures were found more frequently, and lumbar curvatures were reported as second most common.
Radiological validation rates
One of the most important issues of school screening programs conducted for almost 60 years worldwide is the low radiological validation rate despite the high radiological referral rates [7,27,28]. The data on the reported radiological validation rates obtained from the small number of studies ranged from 38% to 74% [27,28].
The radiological verification rate in the TAIS-PR study was 98.8%. To date, this is the highest reported rate of radiological validation. This success of the TAIS-PR study was due to the radiological verification of suspected cases was carried out on the same day on site, as mentioned earlier. Thus, lost cases were prevented, and true prevalence was obtained.
Another strength of our study was that single investigator reviewed all X-Rays. This prevented intra-rater variability, should there be multiple investigators in measuring. In the present study, the ICC value was calculated as 0.97 [95% confidence interval (95% CI) 0.96–0.98] and the intra-rater reliability as 0.74 (detecting curve 5° vs. ≧5°). Obviously, this eliminates the possibility of missing curves ≧10°.
Limitations
Mobile X-Ray devices were used in the TAIS-PR study for radiological verification, thus increasing the costs. It is not possible to recommend the applied method as a routine scoliosis-screening program in point of its costeffectiveness. One of the important limitations of the present study was that the ATR degrees obtained with the scoliometer were not noted, thus, scoliometer measurements and curve magnitudes could not be correlated.
Conclusions
The TAIS-PR study is the most comprehensive study ever conducted in Turkey to date. Radiological validation rate of this study is the highest rate of school-based screening programs reported in the literature until now. The prevalence of AIS in Turkey was similar to that reported in other countries and higher in females. Costeffectiveness analyses are required to determine the value of school screening programs. Since AIS prevalence
increases with age, early diagnosis and treatment is important and the screening should be carried out before the completion of maturation, especially in girls aged 12-14.
REFERENCES
1.
Fadzan M, Bettany-Saltikov J. Etiological theories of adolescent idiopathic scoliosis: past and present. Open Orthop J 2013;29:1466-89. doi: 10.2174/1874325001711011466.
2.
Weinstein SL, Dolan LA, Cheng JC, Danielsson A, Morcuende JA. Adolescent idiopathic scoliosis. Lancet 2008;371:1527-37. doi: 10.1016/S0140-6736(08)60658-3.
3.
Brooks HL, Azen SP, Gerberg E, Brooks R, Chan L. Scoliosis: a prospective epidemiological study. J Bone Joint Surg Am 1975;57:968–72.
4.
Daruwalla JS, Balasubramaniam P, Chay SO, Rajan U, Lee HP. Idiopathic scoliosis. Prevalence and ethnic distribution in Singapore schoolchildren. J Bone Joint Surg Br 1985;67:182–4.
5.
Konieczny MR, Senyurt H, Krauspe R. Epidemiology of adolescent idiopathic scoliosis. J Child Orthop 2013;7:3–9. doi: 10.1007/s11832-012-0457-4.
6.
Hresko MT, Talwalkar V, Schwend R; AAOS, SRS, and POSNA. Early detection of idiopathic scoliosis in adolescents. J Bone Joint Surg Am 2016;98(16):e67. doi: 10.2106/JBJS.16.00224.
7.
Ugras AA, Yılmaz M. Sungur I, Kaya I, Koyuncu Y, Cetinus ME. Prevalence of scoliosis and costeffectiveness of screening in schools in Turkey. J Back Musculoskelet Rehabil 2010;23:1–4. doi: 10.3233/BMR-2010-0247.
8.
Cilli K, Tezeren G, Taş T, Bulut O, Oztürk H, Oztemur Z, et al. School screening for scoliosis in Sivas, Turkey. Acta Orthop Traumatol Turc 2009;43:426-30. doi: 10.3944/AOTT.2009.426.
9.
Yılmaz T, Gökçe A, Naderi S, Yaman O, Dalbayrak S. School screening of adolescent idiopathic scoliosis in 7928 Turkish children. J Turk Spin Surg 2016;3:135-42.
10. Ibisoglu YU, Calis FA, Yagiz On A. Prevalence of scoliosis among primary school children aged 12-14 years living in a town in western Turkey. Turk J Phys Med Rehab 2012;58:109-13. 11. Tezeren G, Ozlu K, Aydemir A, Ayasli A, Kahraman H, Dülgeroglu D. School screening for scoliosis in Ankara. J Turk Spinal Surg 1993;3:92-4. 12. Tanchev P, Dikov D, Dzherov A, Parushev A, Zahariev L, Todorov N, et al. School screening for scoliosis in Sofia: an analysis of screening results of 4800 students. Orthop Trauma 1996;33:69–73.
13. Grivas TB, Koukos K, Koukou UI, Maziotou C, Polyzois BD. The incidence of idiopathic scoliosis in Greece-analysis of domestic school screening programs. Stud Health Technol Inform 2002;91:71-5. 14. Koukourakis I, Giaourakis G, Kouvidis G, Kivernitakis E, Blazos J, Koukourakis M. Screening school children for scoliosis on the island of Crete. J Spinal Disord 1997;10:527-31. 15. National Household Health Survey – Prevalence of Noncommunicable Disease Risk Factors in Turkey 2017 (STEPS). Üner S, Balcılar M, Ergüder T editors. World Health Organization Country Office in Turkey, Ankara, 2018. 16. Bunnell WP. Outcome of Spinal Screening. Spine 1993;18:1572-80. 17. https://www.srs.org/professionals/online-education-and-resources/glossary/revised-glossary-ofterms.(Access: 02 May 2019). 18. McHugh ML. Interrater reliability: the kappa statistic. Biochem Med (Zagreb) 2012;22(3):276-282. 19. Bunnell WP. Selective screening for scoliosis. Clin Orthop Relat Res 2005;434:40-5. 20. Dunn J, Henrikson NB, Morrison CC, Nguyen M, Blasi PR, Lin JS. Screening for adolescent idiopathic scoliosis: a systematic evidence review for the U.S. Preventive Services Task Force. Evidence Synthesis No. 156. AHRQ Publication No. 17-05230-EF-1. Rockville, MD: Agency for Healthcare Research and Quality 2018. PMID: 29638297. 21. Lee CF, Fong DY, Cheung KM, Cheng JC, Ng BK, Lam TP, et al. Referral criteria for scoliosis screening: assessment and recommendations based on a large longitudinally followed cohort. Spine 2010;35:1492-8. doi: 10.1097/BRS.0b013e3181ecf3fe. 22. Lee JY, Moon SH, Kim HJ, Park MS, Suh BK, Nam JH, et al. The prevalence of idiopathic scoliosis in eleven year-old Korean adolescents: a 3 year epidemiological study. Yonsei Med J 2014;55:773-8. doi: 10.3349/ymj.2014.55.3.773. 23. Ueno M, Takaso M, Nakazawa T, Imura T, Saito W, Shintani R, et al. A 5-year epidemiological study on the prevalence rate of idiopathic scoliosis in Tokyo: School screening of more than 250.000 children. J Orthop Sci 2011;16:1-6. doi: 10.1007/s00776-010-0009-z. 24. Zheng Y, Dang Y, Wu X, Yang Y, Reinhardt JD, He C, et al. Epidemiological study of adolescent idiopathic scoliosis in Eastern China. J Rehabil Med 201749:512-9. doi: 10.2340/16501977-2240. 25. Soucacos PN, Soucacos PK, Zacharis KC, Beris AE, Xenakis TA. School-screening for scoliosis: a prospective epidemiological study in Northwestern and central Greece. J Bone Joint Surg Am 1997;79:1498-503.
26. Wong HK, Hui JH, Rajan U, Chia HP. Idiopathic scoliosis in Singapore schoolchildren: a prevalence study 15 years into the screening program. Spine 2015;30:1188-96. 27. Deepak AS, Ong JY, Choon D, Lee CK, Chiu CK, Chan C, et al. The clinical effectiveness of school screening program for idiopathic scoliosis in Malaysia. Malays Orthop J 2017;11:41-6. doi: 10.5704/MOJ.1703.018. 28. Altaf F, Drinkwater J, Phan K, Cree AK. Systematic review of school scoliosis screening. Spine Deform 2017;5:303-9. doi: 10.1016/j.jspd.2017.03.009.
Figure 1. Flow diagram of the study
Figure 2. Box plot and whisker chart showing median (central dark line) Quartiles 1 and 3 as well as minimum and maximum values as per age groups for Cobb angles greater than or equal to 10°.
Table 1. Demographic characteristics of the cases
All cases
Number of cases (%) Mean age (years) ± SD Mean BMI (kg/m2) ± SD Menarche (n (%))
AIS
Female
Male
Female
Male
Total
8162 (50.9%)
7883 (49.1%)
251
118
369
12 ± 1.2
12.1 ± 1.3
12.2 ± 1.4
12.2 ± 1.45
12.2±1.3
19.3 ± 3.8
19.3 ± 3.8
18.7 ± 2.9
18.6 ± 3.6
18.6 ± 3.2
14.1° ± 4.6°
14.6° ± 5.2°
2604 (37.3%)
94 (41.6%)
12.2 ± 1.0
12.3 ± 1.1
Mean age of menarche (months) ± SD Cobb angle, mean ± SD
14.8° ± 5.4°
AIS: Adolescent idiopathic scoliosis, BMI: Body mass index, SD: Standard Deviation,
Table 2. Prevalence of adolescent idiopathic scoliosis by Cobb angle and age distribution
Minor curve (<10o Cobb angle) prevalence
Female
Male
Total
Cobb angle ≧5°
7.1
4.4
5.8
Cobb angle ≧5° – <10°
4.0
2.9
3.5
in all age
3.1
1.5
2.3
≧10 – <12 age
2.7
1.3
2.0
≧12 – <14 age
3.5
1.5
2.5
≧14 age
3.4
2.0
2.7
AIS prevalence according to age distribution
AIS: Adolescent idiopathic scoliosis
Table 3. Distribution of Cobb angles in adolescent idiopathic scoliosis cases
Number of idiopathic scoliosis cases in adolescents Cobb angle Male (n)
%
Female (n)
%
Total (n)
%
M/F ratio
10°–19°
108
29.2
226
61.3
334
90.5
1:2.1
20°–29°
8
2.2
18
4.8
26
7.0
1:2.3
30°–39°
1
0.3
5
1.4
6
1.7
1:5.0
≧40°
1
0.3
2
0.5
3
0.8
1:2.0
Total
118
32.0
251
68.0
369
100.0
1:2.1
M: male, F: female
Table 4. Scoliosis location distribution and curvature types
Convexity Scoliosis pattern Right
Left
Total (%)
102
154
256 (69.3)
Cervical
0
1
1 (0.3)
Cervicothoracic
0
9
9 (2.4)
Thoracic
41
20
61 (16.5)
Thoracolumbar
35
50
85 (23.0)
Lumbar
26
74
100 (27.1)
Single curvature
Double curvature
108 (29.3)
Triple curvature
5 (1.4)
Total
369 (100)