When it comes to adolescent idiopathic scoliosis, GPs have a crucial role. Prompt intervention through early detection at primary care can help your young patients reduce the need for eventual surgery.
When it comes to adolescent idiopathic scoliosis, general practitioners (GPs) have a crucial role. Prompt intervention through early detection at primary care can help your young patients reduce the need for eventual surgery.
INTRODUCTION
What it is
Adolescent idiopathic scoliosis (AIS) is the most common spinal deformity affecting children and adolescents. It refers to a three-dimensional deformity of the spine in the sagittal, coronal and axial planes, with a lateral curvature of 10 degrees or more.
Patients with severe, untreated scoliosis have been shown to have poorer perception of self-image1 and reduced health-related quality of life compared to healthy controls2.
As such, early detection of the condition through screening and early intervention is beneficial, especially in reducing the need for eventual surgery.
Prevalence
The prevalence of AIS in Singapore is estimated to be 1.37% and 0.21% in girls and boys aged 11-12 years respectively, and 2.22% and 0.66% in girls and boys aged 13-14 years respectively.3
In situations when the curvature is around 10 degrees, the female to male ratio is around 1:1. In cases when the curve exceeds 30 degrees, the female to male ratio is 10:1.
School-based screening
Annual school-based screening for scoliosis consisting of visual inspection of the back and the Adam’s forward bend test (FBT) has been implemented in Singapore since 1982, commencing at Primary 5 and till Secondary 2 for girls, and from Secondary 2 till 4 for boys.
Children with more than five degrees of rotation on the FBT are then referred to the Health Promotion Board (HPB) for further evaluation. If the plain radiograph performed at the HPB shows scoliosis in a skeletally immature patient, a referral is made to an orthopaedic surgeon at a tertiary hospital.
PRESENTATION OF AIS
Patients with AIS often have no symptoms. Some, however, may complain of mild back pain or discomfort that does not usually affect their daily activities.
Others may seek medical advice after family members or friends, or even they themselves, have noticed an asymmetrical slant to their trunk or uneven shoulders or waist.
However, it is not unusual for patients with scoliosis to present ‘late’ – ‘late’ being defined as scoliosis with a Cobb angle of 40 degrees or more.
A study performed on our local population4 identified the top three reasons for the delay in seeking tertiary evaluation as:
Not thinking the scoliosis was a problem
Being too busy
Simply not realising they had scoliosis
What GPs Should Look Out For in Scoliosis Patients
Red flags
While the majority of adolescents presenting with scoliosis are otherwise healthy with no significant medical conditions, it is essential that they are screened for red flags which may point to a more sinister underlying pathology.
These red flags include:
The presence of back pain that is well-localised and constant
Back pain that is progressively worsening
Weakness or clumsiness in the upper and lower limbs
The presence of bladder or bowel dysfunction
History taking
In addition, asking about the onset of the menarche or voice break, as well as when the child or parents noted a growth spurt, if any, can be an indication of the skeletal maturity of the child. This has a huge impact on the prognosis of scoliosis and its subsequent management.
Finally, key points in the history may point to nonidiopathic causes of scoliosis:
Birth history: a difficult or prolonged labour may be associated with cerebral palsy and neuromuscular scoliosis
Developmental milestones: a developmental delay may indicate a non-idiopathic cause of scoliosis
Family history of spinal disorders
How GPs Can Screen For Scoliosis
Besides excluding red flags in the history, scoliosis can be picked up in the outpatient setting by:
Looking for waist or shoulder asymmetry when the patient is adequately exposed (Figure 1A)
Inspecting the trunk and limbs for café-au-lait spots and axillary freckling – seen in neurofibromatosis, which is associated with scoliosis
Inspecting the back for sacral dimpling or a hairy patch – often seen in spinal dysraphism (congenital defects in the spinal cord and vertebrae)
Performing a simple screening test: the Adam’s FBT
This involves asking the patient to bend forward at the waist as if to touch their toes, with the elbows and knees extended and palms opposed. (Figure 1B) The GP now stands at eye level with the patient’s back and looks for one side being higher than the other. Using a scoliometer can quantify the degree of rotation in the axial plane. There are also scoliometer apps available online which may be more convenient.
Examining the patient’s gait and posture, in particular looking for a short-limb gait which may indicate a limb length discrepancy In addition, performing a detailed neurological examination testing the motor power, sensory function and reflexes is essential. Asymmetry noted in the reflexes may be an indication of an intraspinal disorder.
When to refer to a specialist
Should there be any positive findings, a referral to the paediatric orthopaedic spine surgeon can be made for further investigations (EOS radiographs and advanced imaging such as MRI, if indicated) and management.
DIAGNOSIS AND MONITORING OF AIS
Full-length standing radiographs
Full-length standing radiographs taken in both the posteroanterior and lateral profiles are essential in order to accurately diagnose and assess the degree of the deformity by measuring the Cobb angle.
In addition, radiographs allow gauging of the skeletal maturity of the child using either the Risser scoring or the Sanders Maturity Scale.
Isolated views of the thoracic or lumbar spine alone do not suffice in diagnosing scoliosis as they may under- or over-exaggerate the actual deformity.
EOS connect imaging system
The EOS connect imaging system (Figures 2 and 3) is a service now available at most tertiary hospitals.
It produces a high-quality image with 50% less radiation as compared to a digital radiograph utilising a conventional X-ray system.
This allows safer care for our paediatric patients who require multiple radiographs during the course of their treatment.
MRI or CT scans
MRI or CT scans of the spine are sometimes performed if indicated, such as when there are neurological deficits or atypical scoliotic curves detected on plain radiographs.
RISK FACTORS FOR AIS CURVE PROGRESSION
Age
| The younger the age at diagnosis, the greater the potential for curve progression at the onset of adolescent growth squrt
|
Gender
| Progression is more common in girls
|
Menarche
| Progression is least common after menarche
|
Remaining skeletal growth
| The more skeletally immature, the greater the risk of curve progression
|
Curve pattern
| Double curves are more likely to progress than single curves
|
Curve magnitude
| The risk of progression increases with curve magnitude
|
Table 1
Adapted from Altaf F, Gibson A, Dannawi Z, Noordeen H. Adolescent idiopathic scoliosis BMJ 2013; 346 :f2508
MANAGEMENT OF AIS
Providing comprehensive care for paediatric patients with scoliosis requires a team-based approach involving the GP, orthopaedic spine surgeon, allied health professionals, prosthetists and orthotists.
Regular assessment and exercises
Patients with mild curves (less than 20 degrees) are observed with regular assessments every four to six months. Physiotherapeutic scoliosis-specific exercises (PSSE) may also be commenced for three-dimensional self-correction, core strengthening and stabilisation of the corrected posture.
Bracing
The primary goal of bracing is to halt curve progression. A brace is usually offered for curves between 20 to 40 degrees in patients who are rapidly growing (Risser stages 0-2).
Patients are recommended to wear the brace for at least 18 hours a day and are encouraged to continue all sporting activities during the bracing period.
Poor compliance is an obstacle to successful brace treatment and the presence of a strong support system that includes the patient’s family, GP, orthopaedic surgeon, orthotist and physiotherapist can help reinforce the importance of bracing to the child.
Bracing is discontinued when the child has reached skeletal maturity or when the magnitude of the curve has exceeded the surgical threshold.
Surgery
It is estimated that about 10% of adolescents with idiopathic scoliosis will eventually require surgical intervention.5
Surgery is considered in skeletally immature patients with curves exceeding 45 degrees and skeletally mature patients with curves exceeding 0 degrees, as the curves in these two scenarios are expected to progress even after maturity, which may lead to an increased risk of low back pain, worsening physical deformity and reduced lung function in some cases.
The aims of surgery are to:
Correct the deformity,
Halt progression by achieving a solid fusion construct, and
Achieve a spine that is balanced in both the coronal and sagittal planes
The gold standard to halt curve progression while providing curve correction remains posterior spinal fusion (PSF) with pedicle screw fixation. There is an increasing use of intraoperative navigation to guide pedicle screw placement. This includes the 7D Machine-vision Image Guided Surgery (MvIGS) system, which has been shown to allow significant reduction in intraoperative radiation exposure, fluoroscopy time, as well as blood loss and length of stay.6
This has allowed both:
CONCLUSION
AIS tends to affect adolescents aged 10-16 years old. While there is no known method of preventing its onset, screening and early detection of the condition can allow prompt intervention and arrest its progression.
GPs play a crucial role in early detection of the condition through directed history taking and physical examination, as well as educating parents and caregivers on the condition and the importance of compliance to treatment.
KEY TAKEAWAYS FOR GPs IN TACKLING AIS
Maintain an index of suspicion for scoliosis, particularly in adolescent patients.
Inspecting the shoulders and waist for asymmetry and performing the Adam’s FBT are quick and convenient ways to screen for potential scoliosis.
If scoliosis is detected in a premenarchal female, there is a higher risk of curve progression, hence early referral to a tertiary specialist is advised.
GPs are a crucial part of the support system for patients receiving brace treatment, to enhance compliance.
REFERENCES
Lee, H., Choi, J., Hwang, JH. et al. Health-related quality of life of adolescents conservatively treated for idiopathic scoliosis in Korea: a cross-sectional study. Scoliosis 11, 11 (2016). https://doi.org/10.1186/s13013-016-0071-1
Asher MA, Burton DC. Adolescent idiopathic scoliosis: natural history and long term treatment effects. Scoliosis. 2006;1:2.
Wong HK, Hui JH, Rajan U, Chia HP. Idiopathic scoliosis in Singapore schoolchildren: A prevalence study 15 years into the screening program. Spine 2005;30:1188-96.
Lee JZ, Lam DJ, Lim KB. Late presentation in adolescent idiopathic scoliosis: who, why, and how often? J Pediatr Orthop B. 2014 Jan;23(1):6-14. doi: 10.1097/01.bpb.0000434243.64440.13. PMID: 24201070.
Parent S, Newton PO, Wenger DR. Adolescent idiopathic scoliosis: etiology, anatomy, natural history, and bracing. Instructional Course Lectures2005;54:529-36.
Lim, K.B.L., Yeo, I.S.X., Ng, S.W.L. et al. The machine-vision image guided surgery system reduces fluoroscopy time, ionizing radiation and intraoperative blood loss in posterior spinal fusion for scoliosis.Eur Spine J 32, 3987–3995 (2023).
Dr Stacy Ng completed her specialist training in 2021 and was elected Fellow of the Royal College of Surgeons (Ortho). She has a sub-specialty interest in conditions affecting the paediatric spine, including scoliosis. She has recently completed her surgical fellowship in complex paediatric spinal deformities at Centre des Massues in Lyon, France. GPs who would like more information on this topic, please contact Dr Ng at [email protected].
GPs can call the SingHealth Duke-NUS Spine Centre for appointments at the following hotlines or click here to visit the website:
Singapore General Hospital: 6326 6060
Changi General Hospital: 6788 3003
Sengkang General Hospital: 6930 6000
KK Women's and Children's Hospital: 6692 2984
National Neuroscience Institute: 6330 6363
