Scoliosis

Author(s): Aloysia Schwabe, MD, Anand Allam, MD

Originally published:11/14/2011

Last updated:05/12/2013

1. DISEASE/DISORDER:

Definition

Scoliosis is descriptive term for athree-dimensional abnormality of the spine including frontal planecurvaturegreater than 10 degrees (Cobb angle >10 degrees).

Etiology

Scoliosis is classified in 5 main categories: idiopathic, neuromuscular, congenital, syndrome-related, and tumor-related.1

Idiopathic scoliosis,by definitiona spinalanomaly of unknown etiology,is themost common form of scoliosis (~80%). This is a diagnosis of exclusion and evaluation reveals no anomalous vertebrae and a normal neurologic exam. Approximately 30%of adolescent idiopathic scoliosis patients have some family history of scoliosis,suggestinga possible genetic correlation.

Neuromuscular disorders are split into neuropathic and myopathic groups (table 2).2

Congenital scoliosis is due to vertebral anomalies caused by failures of formation, segmentation, and midline fusion which likely occurs early in embryogenesis. Non-spinal, visceral, and musculoskeletal malformations commonly coexist with vertebral malformations in congenital scoliosis and other congenital spine deformities.

Syndrome-related scoliosis includes malalignment due to neurofibromatosis, Marfan syndrome, congenital heart disease, Prader-Willi, etc.

Epidemiology including risk factors and primary prevention

The prevalence of idiopathic scoliosis in the general population is approximately 1.9%- 3%for curves greater than 10degrees and 0.3% for curves greater than 20 degrees. This categorization is separated by onset(table 1). Up to 100% of people with neuromuscular conditions also have some form of spinal deformity.3 Injuries, infection, tumor and any form of bony/ligament dysfunction potentially can cause spinal deformity.

Table 1. Types of Idiopathic Scoliosis

Type Age of Onset
Percentage of All Idiopathic Scoliosis
Male:Female Ratio
Common Curve Pattern*
Usual Side of Curve Vertex
Usual Outcome
Infantile < 3 years 1 Males > Females T or T-L Left May spontaneously resolve
Juvenile 3-10 years 12-21 Equal until year 6, then 1:8 T, double major, T-L Right Usually will not resolve spontaneously
Adolescent 10 years – skeletal maturity 80-90 1:5 T, double major, T-L Right Dependent on age of onset and size of curve

*Abbreviations: T, thoracic; T-L,thoracolumbar; double major,2 curveswith nearly equal angles causing minimal visual distortion.

Table adapted with permission from DeLisa’s Physical Medicine and Rehabilitation: Principles ad Practice, table 34.4, p 898.2

Patho-anatomy/physiology

Spinal stability is derived from bone, connective tissue, muscle, and their interaction with the nervous system.2 Dysfunction in any of these elements leads to imbalance and, ultimately, to deformity.

Table 2. Types of ScoliosisbyPathophysiology.

Type Congenital Acquired
Bony Dysfunction Isolated or associated with genitourinaryanomalies, cardiac anomalies, etc.

Winter’s Classification:
Failure of segmentation: Unilateral bar, bloc vertebra

Failure of formation: Nonincarcerated emivertebra, incarcerated emivertebra

Trauma, radiation, tuberculosis, infection, degenerative disease, bone tumors (more commonly metastases)
Elastic Tissue Dysfunction Marfan syndrome, Ehler-Danlos, etc. (affects connective tissue only)

Osteogenesis imperfecta, achondroplasia (affects bone and connective tissue)

Soft tissue contractures (e.g.,due to empyema, surgical treatment, burns, radiation, resultant scarring, radiation fibrosis)
Neuromuscular Dysfunction
Weakness:
Lower motor neuron disorders (e.g.,spinal muscular atrophy, Charcot-Marie-Tooth disease, meningomyelocele)
Myopathic conditions(e.g.,Duchenne muscular dystrophy, Becker muscular dystrophy, congenital hypotonia, myotonic dystrophy)Abnormal central control:
Cerebral palsy (Note that a negative correlation exists between ambulation and spinal deformity)
Spinocerebellar disorders (e.g.,Friedrich ataxia)Abnormal sensory input:
e.g.,Riley-Day familial dysautonomia
Spinal cord injury, syringomelia

Table derived with permission from DeLisa’s Physical Medicine and Rehabilitation: Principles and Practice, p 892-899.2

Disease progression including natural history, disease phases or stages, disease trajectory (clinical features and presentation over time)

Spinal deformity progression varies significantly depending on the etiology. In general, idiopathic scoliosis progresses more aggressively during the pubertal growth spurt. General outcomes are mentioned in table 1. Neuromuscular conditions usually progress aggressively, requiring surgical intervention.Slow progression can occur during adult years.

Specific secondary or associated conditions and complications

Severe scoliosis can lead to skin breakdown (rib rubbing on pelvis), problematic fit for seating, aesthetic concerns and pulmonary compromise due to restrictive lung disease.

2. ESSENTIALS OF ASSESSMENT

History

Evaluation should include the following elements:

  1. Growth rate and maturation, to predict remaining growth and risks for curve progression.
  2. Family history of scoliosis may suggest greater likelihood ofcurve progression.
  3. Past medical and surgical history may reveal renal,cardiac, or multisystem abnormalities that correlate to a syndrome or congenital condition.
  4. Pain or nighttime pain may be associated with an underlying pathologic condition such as spondylolisthesis, Scheuermann kyphosis, syringomyelia, tethered cord, intraspinal tumor, etc. Complaints of pain must be distinguished between mild or fatigue-related pain versus severe pathologic pain, whichrequires further evaluations such as MRI or bone scan. Pain is not commonly associated with idiopathic scoliosis.
  5. Rapid development of a severe curve suggests a nonidiopathic type of scoliosis.
  6. Weakness, sensory changes, gait abnormalities, radiating pain, bowel or bladder control changes and other neurologic symptoms suggest intraspinal pathology such as syringomyelia, tethered cord, tumor, etc.4

Physical examination

Visual inspection:

  1. Skin markings (café-au-lait spots, hyper- or hypopigmentation, signs of neurofibromatosis, dysraphic signs, etc.)
  2. Limb length, trunk shape, balance, symmetry of shoulder height, scapular position, waist shape, pelvic tilt, and chest cage deviation
  3. Pubertal assessment such as stages of breast development, presence of axillary/pubic hair. (Note that pubertal assessment can be done discreetly without fully undressing the patient ,to reduce patient anxiety and apprehension. Girls can be asked to wear a two-piece swim suit at time of making appointment)4
  4. Adam forward-bend test assesses for rib and paraspinal deviation. Performed by having the patient bend forward at the waist with the knees straight. Any asymmetry should be noted as upper thoracic, midthoracic, thoracolumbar and lumbar.

Neurologic exam to rule out intraspinal pathology:

  1. Balance, motor strength in all 4 limbs, sensation, reflexes, gait, tandem walk, and abdominal reflex

Musculoskeletal exam:

  1. Range of motion, joint deformity, joint laxity, etc.
  2. Excess laxity of the joints and/or skin may be related to a syndrome such as Ehler-Danlos or Marfan.4

Functional assessment

Activities of daily living (ADL), Functional Independence Measure (FIM), and WeeFIM measures can be helpful in assessing function(self-care, sitting balance, breathing, feeding, transfers, mobility, ambulation, bowel and bladder management, etc.). Cognition is not affected by scoliosis. Some may become power wheelchair users due to mechanical or cardiopulmonarylimitations. See social role section below regarding behavior and affect.

Laboratory studies

Unnecessary except in work-up for metabolic conditions.

Imaging

  1. Standing postero-anteriorand lateral spine X-rays with Cobb angle measurement
  2. Risser classification of iliac apophysis ossification to determine stage of maturity
  3. Routine MRI not indicated. Consider MRI for congenital scoliosis, abnormal neurologic exam, musculoskeletal deformity such as cavus feet, signs associated with underlying neural tube defect, or left thoracic curvature with rapid progression.
  4. Renal ultrasound or intravenous pyelogramfor congenital scoliosis
  5. Consider cardiac imaging for congenital scoliosis

Supplemental assessment tools

Pulmonary function tests (PFT) for those with severe curvescausing restrictive lung disease. Moderate curves and neuromuscular curves can benefit from baseline PFTs due to risk of pulmonary compromise.

Early predictions of outcomes

Please see section A under pathoanatomy and disease progression.

Social role and social support system

The social impact of scoliosis is dependent on the individual and cultural setting. Today’s highly image conscious society seems to impose greater pressures on women and girls. This phenomenon has a potential impact on body image and emotional health. Studies have shown that patients with idiopathic scoliosis have poorer body image, greater unhappiness, lower self-esteem, increased participation in high risk behaviors, and greater incidence of depression.5 It is important to inquire in this regard and consult a rehabilitation psychologist or social worker to address the emotional concerns of the patient and family, if needed.

3. REHABILITATION MANAGEMENT AND TREATMENTS

Available or current treatment guidelines

NON-OPERATIVE TREATMENT:

Bracing is the mainstay of physiatric management of spinal deformity. Standard bracing principles requiring 3 points of fixation apply. However, this is complicated by the fact that the spine is composed of semi-rigid structures where each link has 6 degrees of freedom. Table 3outlines general bracing guidelinesforvarious etiologies.

Therapeutic exercise is used in conjunction with bracing to prevent secondary complications (atrophy, deconditioning, contracture) of progressive spinal deformity. However, research hasnotshown that exercise alone is effective against idiopathic scoliosis.

Table 3. Role of Orthotic Management in Spinal Deformity of Different Etiologies

Etiology Roles of Orthotic Management Type of Orthosis
Idiopathic Ambulatory patients – to slow progression Rigid
Myopathic/lower motor neuron Seated patients – to provide comfort and support Soft (must evaluate for possible orthosis-related decrease inpulmonary function)
Upper motor neuron To slow progression in seated patients (likely to restrict function in standing patients) Rigid
Congenital bony dysfunction To slow or stop progression in long flexible curves Rigid
Ligamentous dysfunction Insufficient literature; might be able to control curve but effect would be limited by deformation of intervening structures. Consider limiting use to support and comfort. Soft
Degenerative For comfort and support, will not likely affect curve Rigid or semi-rigid

Reprinted with permissionfromDeLisa’s Physical Medicine and Rehabilitation: Principles and Practice,p 901,table 34.5.2

Thetwo basic types of rigid braces are the Milwaukee type CTLSO (criterionstandard) and a variety of TLSO braces (Wilmington, Boston, Charleston, Providence, SpineCor brace, etc.). Meta-analysis studiesshow that the Milwaukee brace is the most effective brace; however, it is the most cumbersome, bulky, and uncomfortable.

Standard of care for brace treatment of idiopathic scoliosis.
Bracing is indicated for most children and adolescents with curves between 25 and 40 degrees who have at least 2 years of growth remaining based on Risser sign (Risser 0, 1, 2) and onset of menses for girls (less than 1 year postmenarche). A low profile, rigid TLSO worn full-time (18-23 hours per day) through skeletal maturity is currently the standard of care for most idiopathic curve patterns with a thoracic curve apex at or below T7.3-5

Surgical Treatment:
Goals for surgical treatment are improved spinal alignment/balance and prevention of subsequent curve progression. Surgical indications are based on curve magnitude, clinical deformity, risk for progression, skeletal maturity and curve pattern. For idiopathic scoliosis, surgical treatment is generally for curves greater than 45 degrees in the skeletally immature and greater than 50 degrees when growth has stopped. Surgery involves spinal fusion with rod placement by anterior approach, posterior approach, or both. Otherconsiderations apply in various conditions. For example, conditions with loss of motor control may require intervention starting at the pelvis.

Translation into practice: practice “pearls”/performance improvement in practice (PIPs)/changes in clinical practice behaviors and skills

Idiopathic scoliosis, although common, is a diagnosis of exclusion. A high percentage of left thoracic curves are pathologic.

Although brace treatmentis the standard of care for progressive curves in much of the developed world,the scientific basis for brace efficacy is weak. Timing of intervention is difficult to determine. Bracing mild curves would lead to over-treatment.However, the margin between curves of 20 degrees to25 degrees (brace initiated) and45 degrees (surgery indicated) is small. Further, adolescents resist brace wear due to the daily wear schedule and duration (as long as 5 years in teenage boys). Thus, bracing is an ongoing challenge in this population.5

4. CUTTING EDGE/EMERGING AND UNIQUE CONCEPTS AND PRACTICE

Cutting edge concepts and practice

Studies in genetic testing, identification of period of peak growth, and fusionless, minimally invasive surgeryshow promise for better understanding of idiopathic scoliosis and its potential cure.5

5. GAPS IN THE EVIDENCE-BASED KNOWLEDGE

Gaps in the evidence-based knowledge

High quality studies investigatingbracing versus surgical intervention are limited because a well-conducted, randomized, control trial requires neutrality on part of the physician, the family and the adolescent.7

The therapeutic effect of exercise on curve correction is uncertain. These methods are used more in Europe despite a weak evidence base.

REFERENCES

  1. Dormans JP. Scoliosis (idiopathic).In: Schwartz MW, ed.5-MinutePediatric Consult.4th ed.Philadelphia, PA: Lippincott Williams & Wilkins; 2005:756-757.
  2. Paul SM. Scoliosis and other spinal deformities. In: Frontera WR,DeLisa JA, Gans BM, eds.DeLisa’sPhysical Medicineand Rehabilitation: Principles and Practice.5th ed. Wolters Kluwer/Lippincott Williams & Wilkins; 2010:Chapter 34, 883-906.
  3. Educational Materials – Scoliosis Research Society (SRS). SRS Web site.http://www.srs.org/professionals/education_materials/index.htm. Accessed August 7, 2011.
  4. Newton PO, Wenger DR.Idiopathic scoliosis.In: Morrissy RT,Weinstein SL, eds.Lovell and Winters Pediatric Orthopaedics. 6th ed. Philadelphia, PA: Lippincott Williams & Wilkins; 2006:695-761.
  5. Goldberg CJ, Moore DP, Fogarty EE, Dowling FE. Scoliosis: a review.Ped SurgInt.2008;24:129-144.
  6. Emans JB. Congenital scoliosis.In: Morrissy RT, Weinstein SL, eds.Lovell andWinters PediatricOrthopaedics. 6th ed. Philadelphia, PA: Lippincott Williams & Wilkins; 2006:764-795.
  7. Negrini S, Minozzi S, Bettany-Saltikov J, et al. Braces for idiopathic scoliosis in adolescents (review).Cochrane DatabaseSyst Rev. 2010;Jan 20(1):CD006850.

Additional Resources

Fayssoux RS, Cho RH, Herman MJ. A history ofbracing for idiopathic scoliosis in North America.Clin Orthop Rel Res. 2010; 468:654-664.

Moore DP, Tilley E, Sugg P. Spinal orthoses in rehabilitation.In:Braddom RLed.PhysicalMedicineandRehabilitation.3rded.Philadelphia, PA: SaundersElsevier;2007:377-79.

Weiss HR, Bess S, Wong MS, Patel V, Goodall D, Burger E. Adolescent idiopathic scoliosis – tooperate or not? a debate article.Patient SafetySurg.2008; www.pssjournal.com/content2/1/25. Accessed October 24, 2011.

Author Disclosure

Aloysia Schwabe, MD
Research grant – NIH: Baclofen for Spasticity in Cerebral Palsy; Paid consultant for Allergan

Anand Allam, MD
Nothing to Disclose

Related Articles