Strategies for Treating Scoliosis in Early Childhood
; ; ; ; ;
Background: Scoliosis in early childhood is defined as abnormal curvature of the spine of any etiology that arises before age 10. The affected children are at high risk of developing restrictive pulmonary dysfunction. The treatment presents major challenges because of the complexity and high morbidity of the disease.
Methods: This article is based on pertinent articles retrieved by a selective literature search, and on the results of a retrospective study by the authors.
Results: In addition to conservative treatment methods including physiotherapy, casts, and corsets, progressive scoliosis usually requires early surgical intervention. In recent years, many different so-called non-fusion techniques have been developed for the surgical treatment of early childhood scoliosis. The goal of this new strategy is to avoid early fusion procedures and to enable further growth of the rib cage, lungs, and spine in addition to correcting the scoliosis. The authors also present their own intermediate-term results with a novel growth-preserving spinal operation that exploits magnet technology.
Conclusion: Because of the low prevalence and heterogeneous etiology of early childhood scoliosis, the literature to date contains no randomized controlled therapeutic trials concerning this small group of high-risk patients. For the treatment to succeed, it is essential for specialists from all of the involved medical disciplines to work closely together. Conservative measures such as physiotherapy, casts, and corsets can delay the (frequent) need for surgery or even make surgery unnecessary, particularly in the idiopathic types of early childhood scoliosis. The new non-fusion techniques enable continued growth of the spine, rib cage, and lung in addition to correcting the scoliosis.
Early-onset scoliosis (EOS) is defined as a curvature of the spine of any etiology, occurring before the age of 10 years (1, 2). The magnitude of scoliosis is assessed on an anteroposterior (AP) radiograph of the spine, using the Cobb method. Scoliosis is defined as a spinal curve angle (Cobb angle) greater than 10 degrees. To treat scoliosis, comprehensive knowledge of its causes, the normal development of chest and spine, and the natural course of scoliosis is required. Children under the age of 10 years with progressive EOS are during the critical phase of the development of the lungs at high risk of developing restrictive lung disease as the result of the thoracic cage deformity caused by the scoliosis (3). Muirhead et al. estimated the risk of moderate and severe ventilation impairment associated with infantile and congenital EOS to be 34% (4). The therapeutic spectrum for EOS extends from clinical monitoring, physiotherapy, serial casting, and bracing to growth-sparing surgical techniques. Today, the first-line surgical treatment of EOS relies on the placement of implants allowing for further growth of the spine. This approach has replaced early fusion surgery which is now obsolete.
The current aim of the treatment of early-onset scoliosis is to control scoliosis progression, while allowing for further growth of the spine and thorax.
Prevalence and etiology
The exact prevalence of EOS is unknown. For adolescent idiopathic scoliosis >10 degrees, the prevalence is reported to be 2–3% (5). Treatment of EOS is very complex due the inhomogeneity of the conditions and the diverse comorbidities. Due to the variety of underlying factors, scoliosis has no general pathophysiological pathway.
Progression of EOS varies widely according to severity and etiology. It is distinguished between
- congenital malformations,
- neuromuscular disease, such as spinal muscle weakness or meningomyelocele,
- scoliosis-associated syndromes, such as Marfan syndrome or Ehlers–Danlos syndrome,
- neurofibromatosis, and
- idiopathic scoliosis.
Congenital scoliosis with innate vertebral body malformations or complex malformations, including thoracic dysplasia or spondylocostal dysplasia (Jarcho–Levin syndrome) require specific and early treatment (eTable).
Idiopathic scoliosis is described as infantile idiopathic scoliosis if it presents in patients up to 3 years of age and as juvenile idiopathic scoliosis if it presents in patients 4 to 9 years of age (Box). Two types of infantile idiopathic scoliosis are distinguished: resolving, which takes a benign course with spontaneous remission (in up to 80% of cases), and malignant progressive (6). If left untreated, the course of infantile progressive scoliosis is unfavorable with high morbidity and mortality from cardiopulmonary complications (7). Boys and girls are equally affected (8). Based on the scoliosis curve type, the course of the disease is categorized as either benign or malignant. While a flexible harmonic c-shaped curve is typically benign, short structural abnormalities are often malignant/progressive in nature (6). As a general rule, whole spine magnetic resonance imaging (MRI) should be performed in all patients with progressive scoliosis and a Cobb angle of >20 degrees. In their study on 504 cases with infantile or juvenile scoliosis who were scanned with MRI, Zhang et al. found in 18.7% of patients intraspinal abnormalities, such as Arnold–Chiari, tethered-cord, syrinx and split-cord malformations (9).
Pulmonary problems, thoracic and spinal growth
In EOS, pulmonologists are especially concerned about the functional integrity of the lung parenchyma which translates into physiological gas exchange. The basic requirement for this is an undisturbed pre- and especially postnatal lung development. The formation of the alveoli, i.e. the differentiation from the primary to the secondary septa, starts at 36 weeks’ gestation and ends by age 3 years; consequently, at the time of birth only about one third of the later number of alveoli are functional. The lungs have developed adult morphology only by age 3 years; the mature lungs then enter into a period of “simple” growth (10, 11). The thoracic volumes in the newborn, by age 5 years and at age 10 years are 6%, 30% and 50%, respectively, of the final thoracic volume at skeletal maturity (12). Thus, if the thoracic cage configuration is compromised by, for example, early-onset scoliosis or early spinal fusion surgery, both the structural maturation and the quantitative development of lung parenchyma are affected (13). Especially during the first 5 years after birth, the spine from S1 to T1 grows at a very fast rate of 2 cm/year. It then plateaus between 5 and 10 years after birth (1 cm/year), followed by another acceleration (1.8 cm/year) during the growth spurt in puberty (12).
Indication for surgery
The decision whether surgical treatment is indicated in a patient with EOS should be based on scoliosis progression and/or the development of a chest wall deformity, rather than solely relying on the Cobb angle. However, surgery is generally indicated in patients with progressive scoliosis >50 degrees (14–16).
Both conservative and surgical treatment of scoliosis in early childhood are challenging because of the impact of growth and the heterogeneity of the condition. The three columns of conservative treatment of EOS are physiotherapy, serial casting, and bracing. For the surgical treatment of early-onset scoliosis, growth-sparing procedures have become indispensable (Box).
From our point of view, the use of specific physiotherapy strategies is a crucial element of conservative scoliosis treatment and should be initiated when mild deformities (Cobb angle <20 degree) are present. However, the available evidence for EOS is weak. Small studies on adolescent idiopathic scoliosis (AIS) with short follow-up periods evaluating patients with mild scoliosis showed some degree of efficacy (22–24). The goals of physiotherapy are to stabilize the spine and the trunk muscles and to prevent secondary functional impairments.
Among the various etiologies of EOS, idiopathic EOS is most responsive to casting. Derotating and elongating plaster casting is applied on a special casting table (Risser table) under general anesthesia. Correct use does not result in additional deformation of the thoracic cage. The goal of serial casting is to achieve derotation and straightening of the curve. Altogether, the cast is changed three times and each cast brace is to be worn for one month. Once this series is completed, the patient will receive brace treatment. Serial casting can usually be applied in children up to age 5 years. Especially in children who do not have a syndrome, complete correction of the scoliosis can be achieved with this treatment approach. The techniques of serial casting described by Mehta (25) are well documented and achieve impressive results in the conservative treatment of idiopathic early-onset scoliosis.
As the third column, bracing plays an important role in the conservative treatment of idiopathic EOS. Besides the individually fitted brace, the basic requirement for successful bracing treatment is the multidimensional follow-up by the treating physicians, orthopedic technicians, and physiotherapists. Especially in young children, the horizontally aligned ribs are very soft so that inadequate pressure exerted by an ill-fitted brace can cause thoracic deformities by itself. Thus, bracing treatment should be performed according to the principles of Mehta (25) in EOS patients with a Cobb angle >20 degrees. The goal of bracing should be to reduce the primary curve by 50%. With regard to the various types of braces, the modified Chêneau brace and the Boston brace have been proven to be effective; this explains their widespread use (26). Apart from the correct fit of the brace, good patient guidance plays a key role, because treatment success mostly depends on acceptance and wearing duration. Solid evidence is available to support the use of brace treatment for idiopathic adolescent scoliosis (patients >10 years of age) (27). Katz et al. showed that if the brace is worn >12 h/day, 82% of patients experienced no further scoliosis progression (28). The prospective randomized level-1 BrAIST study demonstrated the efficacy of bracing in adolescent idiopathic scoliosis relative to watchful waiting alone. Brace treatment was successful in 75% of patients in the bracing group compared to 42% of patients in the group with watchful waiting alone. Successful treatment was defined as scoliosis with a Cobb angle <50 degrees at skeletal maturity.
Furthermore, the clear relationship between daily wear time of the brace and the efficacy of the treatment was confirmed. Wear times of 0–6 h/day resulted in improvements in 41% of patients, while the success rates with wear times >12.9 h/day were 90–93% (29).
In pediatric patients, spinal fusion surgery leads to disproportionate growth with shorter trunk length and the associated secondary effects on chest wall development and the development of the lungs. Karol et al. showed that the number of fused spinal segments is closely correlated with reduced vital capacity. In order to prevent restrictive lung function in adulthood, thoracic height (T1–T12) should not be below 22 cm at skeletal maturity (30). Thus, spinal fusion surgery, the standard of care for major adolescent scoliosis, should no longer play a role in the management of EOS in early childhood scoliosis or, if indispensable, should only by performed over a short length, as, for example, during resection of half the vertebral body. Various distraction-based “grow-along” non-fusion techniques, such as the Vertical Expandable Prosthetic Titanium Rib (VEPTR) or the conventional growing rod technique, have been developed. However, repeated surgical distractions had to be performed to ensure that these implants can “grow along”. Distraction surgery is typically performed every 6 months. It is associated with a significant adverse event rate and considerable psychological stress for the children (31–33).
With the Shilla growth guidance technique, certified since 2012, the primary curve of the scoliosis is instrumented with pedicle screws and corrected using rods. Proximally and distally of the deformity, the rods are guided by multi-axial sliding screws, designed to enable further spinal growth along the rods (34). Further techniques include anterolateral tethering and the use of staples; however, so far these procedures have only been evaluated in very small patient populations (35). These techniques involve the placement of staples in the convex side of the vertebral bodies. The resulting epiphysiodesis effect, which has also been used successfully to control the growth of extremities, straightens the curve with growth without spinal fusion.
The most advanced non-fusion technique is the magnetically controlled growing rod. These growing rods are surgically anchored in the spine cranially and caudally of the scoliosis. In contrast to conventional growing rod systems, these rods can be transcutaneously distracted using electromagnets. These distractions are usually performed every 4 months on an outpatient basis without anesthesia (36), sparing these children from repeated surgical lengthening procedures (37), postoperative pain, and inpatient stays (Box).
Besides choosing an appropriate non-fusion technique, careful preoperative decision-making as to whether the procedure is indicated as well as the assessment and evaluation of the risks of surgery and anesthesia are essential. Once skeletal maturity is reached, implant removal with subsequent spinal fusion surgery is required to prevent future progression of the deformity. Over the course of the disease, clinical and radiographic follow-up assessments are required.
Due to the etiological diversity of early-onset scoliosis combined with its low prevalence, randomized controlled studies evaluating this small high-risk patient population are scarce in the literature. Thus, successful management of EOS depends on good and close multidisciplinary cooperation of all healthcare professionals involved. Conservative strategies, such as physiotherapy, casting and bracing, can delay the time of surgical correction which is often required. However, especially in idiopathic early-onset scoliosis, conservative treatment alone may achieve satisfactory outcomes. In patients who experience progression of scoliosis despite conservative treatment (Cobb angle >50 degrees), comprehensive interdisciplinary assessment of the child as a basis for risk evaluation is required. Besides the correction of the curve, new non-fusion techniques ensure the further growth of the spine, thoracic cage, and lungs. With this approach, early spinal fusion surgery on the growing child can be avoided (38–40).
Conflict of interest statement
Dr. Ridderbusch received reimbursement of travel and accommodation expenses from Orthovative. He received fees for preparing continuing medical education events from Nuvasive.
Prof. Stücker received fees for conference participation and reimbursement of travel and accommodation expenses from Nuvasive. He also received fees from Nuvasive for preparing continuing medical education events.
Manuscript received on 26 April 2017, revised version accepted on 19 March 2018
Translated from the original German by Ralf Thoene, M.D.
Dr. med. Karsten Ridderbusch
Abteilung für Kinderorthopädie
22763 Hamburg, Germany
Dr. med. Karsten Ridderbusch, PD Dr. med. Alexander S. Spiro, Prof. Dr. med. Ralf Stücker,
Prof. Dr. med. Martin Rupprecht
Department of Orthopedics, University Medical Center Hamburg-Eppendorf (UKE), Hamburg:
Dr. med. Karsten Ridderbusch, PD Dr. med. Alexander S. Spiro, Prof. Dr. med. Ralf Stücker,
Prof. Dr. med. Martin Rupprecht
Department of Pediatric Neurosurgery, Altona Children‘s Hospital, Hamburg: Dr. med. Philip Kunkel
Department of Pediatrics, Altona Children‘s Hospital, Hamburg: Dr. med. Benjamin Grolle
Dr. Kunkel received fees for preparing continuing medical education events from Nuvasive.
Dr. Spiro, Dr. Grolle, and Prof. Rupprecht declare that no conflict of interest exists.
|1.||Akbarnia BA, El-Hawary R: Letter to the editor, early onset scoliosis: time for consensus. Spine Deform 2015; 3: 105–6 CrossRef MEDLINE|
|2.||Skaggs DL, Guillaume T, El-Hawary R, et al.: Early onset scoliosis consensus statement, SRS Growing Spine Committee. Spine Deform 2015; 3: 107 CrossRef|
|3.||Stücker R: The growing spine: normal and abnormal development. Orthopäde 2016; 45: 534–9 CrossRef MEDLINE|
|4.||Muirhead A, Conner AN: The assessment of lung functions in children with scoliosis. J Bone Joint Surg (Br) 1985; 67B: 699–702 CrossRef|
|5.||Weinstein SL: Natural history. Spine 1999; 24: 2592–600 CrossRef|
|6.||Lloyd-Roberts GC, Pilcher MF: Structural idiopathic scoliosis in infancy: a study of the natural history of 100 patients. J Bone Joint Surg Br 1965; 47: 520–3 CrossRef MEDLINE|
|7.||Pehrsson K, Larsson S, Oden A, Nachemson A: Long-term follow-up of patients with untreated scoliosis. A study of mortality, causes of death, and symptoms. Spine 1992; 17: 1091–6 CrossRefMEDLINE|
|8.||Trobisch P, Suess O, Schwab F: Idiopathic scoliosis. Dtsch Arztebl Int 2010; 107: 875–83 CrossRef|
|9.||Zhang W, Sha S, Xu L, et al.: The prevalence of intraspinal anomalies in infantile and juvenile patients with „presumed idiopathic“ scoliosis: a MRI-based analysis of 504 patients. BMC Musculoskelet Disord 2016; 17: 189 CrossRef MEDLINE PubMed Central|
|10.||Burri PH: Structural aspects of prenatal and postnatal development and growth of the lung. In: McDonald J (ed.): Lung growth and development. Dekker, New York 1997: 1–35.|
|11.||Koumbourlis AC: Chest wall abnormalities and their clinical significance in childhood. Paediatric Respiratory Rev 2014; 15: 246–54 CrossRef MEDLINE|
|12.||Dimeglio A, Canavese F, Charles YP: Growth and adolescent idiopathic scoliosis: when and how much? J Pediatr Orthop 2011; 31 (Suppl 1): 28–36 CrossRef MEDLINE|
|13.||Mehta HP, Snyder BD, Baldassari SR, et al.: Expansion thoracoplasty improves respiratory function in a rabbit model of postnatal pulmonary hypoplasia: a pilot study. Spine 2010, 35: 153–61 CrossRef MEDLINE|
|14.||Edgar M, Mehta M: Long-term follow-up of fused and unfused idiopathic scoliosis. J Bone Joint Surg 1988; 70B: 712–6 CrossRef|
|15.||Weinstein SL: Idiopathic scoliosis. Natural history. Spine 1986; 11: 780–3 CrossRef|
|16.||Weinstein SL, Ponseti IV: Curve progression in idiopathic scoliosis. J Bone Joint Surg 1983; 65A: 447–55 CrossRef|
|17.||McMaster MJ, Macnicol MF: The management of progressive infantile idiopathic scoliosis. J Bone Joint Surg (Br) 1979; 61-B: 36–42 CrossRef|
|18.||Sponseller PD, Yazici M, Demetracopoulos C, Emans JB: Evidence basis for management of spine and chest wall deformities in children. Spine 2007; 32 (Suppl 19): 81–90 CrossRef MEDLINE|
|19.||Fernandes P, Weinstein SL: Natural history of early onset scoliosis. J Bone Joint Surg Am 2007; 89 (Suppl 1): 21–33 CrossRef CrossRef MEDLINE|
|20.||Campbell RM, Smith MD, Mayes TC, et al.: The characteristics of thoracic insufficiency syndrome associated with fused ribs and congenital scoliosis. J Bone Joint Surg (Am) 2003; 85-A: 399–408 CrossRef MEDLINE|
|21.||Campbell RM, Smith MD: Thoracic insufficiency syndrome and exotic scoliosis. J Bone Joint Surg (Am) 2007; 89-A (Suppl): 108–22 CrossRef CrossRef|
|22.||Rigo M, Quera-Salvá G, Villagrasa M, et al.: Scoliosis intensive out-patient rehabilitation based on Schroth method. Stud Health Technol Inform 2008; 135: 208–27 MEDLINE|
|23.||Weiss HR, Klein R: Improving excellence in scoliosis rehabilitation: a controlled study of matched pairs. Pediatr Rehabil 2006; 9: 190–200 CrossRef MEDLINE|
|24.||Schreiber S, Parent E, Moez E, et al.: The effect of Schroth exercises added to the standard of care on the quality of life and muscle endurance in adolescents with idiopathic scoliosis—an assessor and statistician blinded randomized controlled trial: “SOSORT 2015 Award Winner” Scoliosis 2015; 10: 24 CrossRef MEDLINE PubMed Central|
|25.||Mehta MH: Growth as a corrective force in the early treatment of progressive infantile scoliosis. J Bone Joint Surg Br 2005; 87: 1237–47 CrossRef MEDLINE|
|26.||Weinstein SL, Dolan LA, Wright JG, et al.: Design of the Bracing in Adolescent Idiopathic Scoliosis Trial (BrAIST). Spine 2013; 38: 1832–41 CrossRef MEDLINE PubMed Central|
|27.||Helfenstein A, Lankes M, Ohlert K, et al.: The objective determination of compliance in treatment of adolescent idiopathic scoliosis with spinal orthoses, Spine 2006; 31: 339–44 CrossRef MEDLINE|
|28.||Katz DE, Herring JA, Browne RH, Kelly DM, Birch JG: Brace wear control of curve progression in adolescent idiopathic scoliosis. J Bone Joint Surg Am 2010; 92: 1343–52 CrossRef MEDLINE|
|29.||Weinstein SL, Dolan LA, Wright JG, Dobbs MB: Effects of bracing in adolescents with idiopathic scoliosis. N Engl J Med 2013; 369: 1512–21 CrossRef MEDLINE PubMed Central|
|30.||Karol LA, Johnston, C, Mladenov K, Schochet P, Walters P, Browne RH: Pulmonary function following early thoracic fusion in non-neuromuscular scoliosis. J Bone Joint Surg (Am) 2008; 90: 1272–81 CrossRef MEDLINE|
|31.||Bess S, Akbarnia BA, Thompson GH, et al.: Complications of growing-rod treatment for early-onset scoliosis: analysis of one hundred and forty patients. J Bone Joint Surg (Am) 2010; 92: 2533–43 CrossRef MEDLINE|
|32.||Sankar WN, Acevedo DC, Skaggs DL: Comparison of complications among growing spinal implants. Spine 2010; 35: 2091–6 CrossRef MEDLINE|
|33.||Flynn JM, Matsumoto H, Torres F, Ramirez N, Vitale MG: Psychological dysfunction in children who require repetitive surgery for early onset scoliosis. J Pediatr Orthop 2012; 32: 594–9 CrossRef MEDLINE|
|34.||Wilkinson JT, Songy CE, Bumpass DB, et al.: Curve modulation and apex migration using shilla growth guidance rods for early-onset scoliosis at 5-year follow-up. J Pediatr Orthop 2017 [Epub ahead of print] CrossRef MEDLINE|
|35.||Boudissa M, Eid A, Bourgeois E, et al.: Early outcomes of spinal growth tethering for idiopathic scoliosis with a novel device: a prospective study with 2 years of follow-up. Childs Nerv Syst 2017; 33: 813–8 CrossRef MEDLINE|
|36.||Ridderbusch K, Rupprecht M, Kunkel P, Stücker R: Non-fusion techniques for treatment of pediatric scoliosis. Orthopäde 2013; 42: 1030–7 CrossRef MEDLINE|
|37.||Ridderbusch K, Rupprecht M, Kunkel P, Hagemann C, Stücker R: Preliminary results of magnetically controlled growing rods for early onset scoliosis. J Pediatr Orthop 2017; 37: e575–80 CrossRef MEDLINE|
|38.||Cheung KM, Cheung JP, Samartzis D, et al.: Magnetically controlled growing rods for severe spinal curvature in young children: a prospective case series. Lancet 2012; 379: 1967–74 CrossRef|
|39.||Akbarnia BA, Cheung K, Noordeen H, et al.: Next generation of growth-sparing technique: preliminary clinical results of a magnetically controlled growing rod (MCGR) in 14 patients with early onset scoliosis. Spine 2013; 38: 665–70 MEDLINE|
|40.||Dannawi Z, Altaf F, Harshavardhana NS, Elsebaie H, Noordeen H: |
Early results of a remotely operated magnetic growth rod in early-onset scoliosis. Bone Joint J 2013; 95-B: 75–80 CrossRef MEDLINE