Dr. Kevin Yip

Dr Kevin Yip
Orthopaedic Surgeon
MBBS(UK), FRCS(EDIN), FAM(SING), FHKCOS(ORTHO)

Featured on Channel NewsAsia

Scoliosis

Basics
Description
  • Scoliosis is a 3D curvature of the spine, best appreciated on an AP radiograph and physical examination.
  • Both thoracic and lumbar segments of the spine may be affected.
  • It is defined as a curve >10°.
  • Classification:
    • Etiology:
      • Idiopathic
      • Congenital
      • Neuromuscular
      • Connective tissue
      • Degenerative
    • Location (of the apex or middle of the curve):
      • Thoracic
      • Thoracolumbar
      • Lumbar
    • Subclassification of idiopathic scoliosis by age:
      • Infantile (<3 years)
      • Juvenile (3-10 years)
      • Adolescent (>11 years)
Epidemiology
  • The most common type is idiopathic scoliosis.
  • Scoliosis may occur at any age.
  • The most common age at diagnosis of idiopathic scoliosis is 11-13 years.
Prevalence
  • Small curves of idiopathic scoliosis are almost equally prevalent in males and females.
  • Females, however, are 3-4 times more likely to develop progression of the curve.
  • In scoliosis other than the idiopathic type, less difference in gender-related prevalence is noted.
  • Prevalence of curves >10° is ~2-3%.
  • Prevalence of curves requiring bracing (>25°) is ~0.3%.
  • Prevalence of curves requiring surgery is ~1 in 1,000.
Risk Factors
  • Progressive idiopathic scoliosis
  • Positive family history
  • Female gender
  • Premenarchal status
  • Paralytic scoliosis
  • Severe spinal cord injury before adolescence
  • Scoliosis in cerebral palsy, including total involvement
Genetics
Idiopathic scoliosis is transmitted as autosomal dominant, with incomplete penetrance and variable expressivity.
Etiology
  • Idiopathic scoliosis:
    • Theories about the cause of idiopathic scoliosis include a subtle connective-tissue abnormality or neurohormonal defect.
    • Causes of congenital scoliosis include hemivertebrae and fusions between vertebrae.
  • Neuromuscular scoliosis:
    • Cerebral palsy
    • Traumatic paralysis
    • Spina bifida
    • Poliomyelitis
    • Friedreich ataxia
    • Virtually any systemic neurologic condition that affects the trunk
  • Connective tissue-associated scoliosis:
    • Marfan syndrome
    • Ehlers-Danlos syndrome
    • NF
    • Down syndrome
Associated Conditions
  • Almost any systemic neurologic disorder that affects the trunk
  • Most connective-tissue disorders
Diagnosis
Signs and Symptoms
  • Varied, depending on the location of the spine affected
  • For thoracic curves, the ribs are rotated on the convex side, producing a rib hump and a more prominent scapula on the same side.
  • With thoracolumbar and lumbar curves, 1 side of the pelvis becomes more prominent, giving the appearance of a high hip.
  • Many, but not all, teens develop increased pain in the area of the curve.
  • Symptoms are few until adulthood, when back pain and nerve root pain may develop.
Physical Exam
  • Examine the patient, while he or she is standing, to see shoulder, rib, and hip asymmetry.
  • Measure leg lengths.
  • Perform the forward bend test with the patient’s legs straight and observe the entire spine for asymmetry between the right and left sides.
    • This test is most useful and highly sensitive, and it is used in school screening programs.
    • If asymmetry is present, measure the slope between the right and left sides of the rib cage.
    • Some patients with a positive forward bend test do not have severe scoliosis.
    • Follow-up a positive test with a radiograph if the rib slope is >6°.
    • Repeat the test if an abnormality is found.
  • Quantify rib prominence or a hump by a scoliometer.
  • Observe any kyphosis and lordosis.
  • Inspect the skin over the entire spine for dimples, hair, or vascular markings, which may signal an underlying congenital anomaly.
  • Rule out ligamentous laxity.
  • Examine for cafe-au-lait spots or neurofibromas.
  • Perform a careful neurologic examination, which can be practically done by observing gait and 1-legged hop and by testing reflexes.
  • Assess the patient’s physical maturity by checking for secondary sexual characteristics such as axillary and facial hair, skin changes, breast development.
  • Measure the height for serial comparison.
Tests
Imaging
  • Radiography:
    • Standing posteroanterior radiography of the entire spine is indicated.
    • Lateral films should be obtained if associated abnormal kyphosis is present.
    • Spine films usually show the iliac crests and allow determination of the Risser stage for skeletal maturity.
      • The Risser stage is the amount of ossification of the iliac growth cartilage.
      • Risser 0, unossified, skeletally immature; Risser V, fully ossified, mature.
    • Presence of an open triradiate cartilage of the hip indicates that the growth spurt has not been completed.
  • MRI is indicated only if spinal cord disease is possible.
Pathological Findings
  • The vertebrae are rotated toward the convexity of the curve.
  • In addition, individual vertebrae are misshapen because of growth while curved.
Differential Diagnosis
  • Isolated rib rotation may occur without scoliosis.
  • Kyphosis (a curvature in the sagittal plane only, which may be confused with scoliosis), clavicle fracture, or Sprengel deformity may give the appearance of a high shoulder.
  • Leg-length inequality may cause the appearance of a high hip.
Treatment
General Measures
  • The spine in patients with scoliosis is not unstable.
  • Encourage patients to be as active as possible.
  • Physical therapy and exercise if pain or stiffness is present
  • Patients with minor curves (<25°) should be observed if they are still growing, but they can be discharged if skeletal maturity has been reached.
  • Patients with moderate curves (25-40°) should be braced if substantial growth remains.
  • Patients with large curves (>45°):
    • See an orthopaedic surgeon to determine whether correction is indicated.
    • Surgery offered.
Special Therapy
Physical Therapy
  • Strengthening and stretching of abdominal and extensor muscles if pain exists
  • Not indicated for routine cases of scoliosis
  • Does not help correct the curves
Complementary and Alternative Therapies
Yoga may be helpful for back discomfort.
Surgery
  • If a curve is to be fused, 1 or 2 rods are used to correct the curve, and a bone graft is placed along the rod to cause the vertebrae to fuse.
    • Only the curved region is fused.
    • The neurologic risk is currently <1%.
Follow-up
Patients should be followed at least until maturity.
Prognosis
  • Pulmonary compromise, including cor pulmonale in congenital or neuromuscular curves, occurs mainly in patients with curves >100°.
  • Most untreated curves >40-50° in adulthood slowly become worse.
Complications
  • Severe curves (>70°) occasionally may progress to the point where they compromise pulmonary function.
  • Curves >40° pose an increased risk of back pain in adulthood.
  • Surgical complications include neurologic injury (<1%), infection, and failure of the vertebrae to fuse.
Patient Monitoring
  • Growing children should be seen every 4-6 months, usually with radiographs.
  • Adults should be seen every 1-5 years.
  • Patients with congenital scoliosis should be monitored for associated anomalies.
Miscellaneous
Codes
ICD9-CM
  • 737.30 Idiopathic scoliosis
  • 754.2 Congenital scoliosis
Patient Teaching
  • Instruct patients in the general guidelines and treatment options.
  • Remind parents of the genetic nature of the condition so that relatives and young siblings with scoliosis may be detected while bracing is still an option.
Prevention
  • Curve worsening may be effectively prevented in growing children by use of a brace.
    • It must be worn 18-23 hours per day.
    • This intervention is effective in ~75% of patients.
    • Bracing does not correct curves.
FAQ
Q: What is the cause of scoliosis?
A: It is not known. It often is passed along in families. It may be a subtle disorder of balance or spinal growth.
Q: Can physical therapy or exercises slow or halt the worsening of the curve?
A: No evidence suggests that it can.
Q: Can bracing correct scoliosis?
A: It rarely produces any permanent correction.
Q: Does scoliosis affect internal organs?
A: It is associated with decreased pulmonary function in curves >70°. There is little documentation of effects on cardiac, gastrointestinal, or genitourinary function.

Comments are closed.