Scheuermann’s Disease

Other Names

• Osteochondrosis of the Vertebral Endplate
• Avascular Necrosis of the Vertebral Endplate
• Avascular Necrosis of the Inferior Vertebral Endplate
• Avascular Necrosis of the Superior Vertebral Endplate
• Scheuermann kyphosis
• Juvenile kyphosis
• Juvenile discogenic disease

Pathophysiology

• General
  • Diagnosis is typically made between the ages of 12 and 17 years
  • Parents tend to notice a postural or “hunchbacked” appearance
  • Patients may also endorse back pain
• Discordant vertebral endplate mineralization and ossification during growth
  • This leads to asymmetric vertebral body growth and wedge-shaped vertebral bodies
  • 3 adjacent vertebral wedged vertebral bodies > 5° are pathognomonic
• The thoracic spine is most commonly affected, followed by the lumbar spine
  • The rigidity of curve distinguishes from postural kyphosis
• The exact etiology is poorly understood, likely multifactorial and theories include
  • The autosomal dominant component has been demonstrated in twin studies
  • Avascular or osteonecrosis of anterior apophyseal ring
  • Herniation of disc material leading to loss of anterior height
  • Abnormal collagen and proteoglycan ratio
  • Dural cysts
  • Biomechanical stress
  • Increased HGH secretion
  • Osteoporosis due to dysfunction of calcium metabolism
  • Inflammatory disease
  • Hypovitaminosis

Associated Conditions

• Hyperkyphosis
• Hyperlordosis
• Spondylolysis
• Scoliosis

Pathoanatomy

• Vertebral Body
  • Wedged anteriorly, typically in adjacent fashion
  • Anterior Longitudinal Ligament may be thickened
  • Intervertebral Disc may be narrowed

Differential Diagnosis

• Fractures
  • Compression Fracture
  • Burst Fracture
  • Chance Fracture
  • Spinous Process Fracture
  • Transverse Process Fracture
  • Rib Fracture
  • Sacral Stress Fracture
• Neurological
  • Lumbar Radiculopathy
  • Cauda Equina Syndrome
  • Sciatica
• Musculoskeletal
  • Mechanical Back Pain
  • Scoliosis
  • Kyphosis
  • Herniated Disc
  • Facet Joint Pain
  • Sacroilliac Joint Pain
  • Spinal Stenosis
  • Spondylolysis
  • Spondylolisthesis
  • Hyperlordosis
  • Baastrups Disease
• Autoimmune
  • Ankylosing Spondylitis
• Infectious
  • Spinal Epidural Abscess
  • Osteomyelitis
• Pediatric
  • Scheuermann’s Disease

Diagnosis

• History
  • Up to 50% of patients will endorse lower back pain, more commonly in thoracolumbar deformities than isolated thoracic
  • Most will have some sort of cosmetic or postural deformity
  • Clothes may fit differently, shoulders appear more rounded
  • Typically no inciting event
• Physical Exam: Physical Exam Back
  • Inspection will identify a rigid, kyphotic or even hyperkyphosis curve
  • Typically accentuated by forwarding bending
  • The curve does not resolve with extension, prone or supine
  • May also identify cervical or thoracic lordosis, scoliosis or tight hamstrings
• Special Tests

Radiographs

• Standard Radiographs Lumbar Spine, Standard Radiographs Thoracic Spine
  • The imaging modality of choice initially
  • Consider imaging the entire spine regardless of symptom location
• Findings on the lateral view
  • Rigid hyperkyphosis > 40°
  • Anterior wedging > 5° on 3 or more adjacent vertebral bodies
  • Does not improve with hyperextension
• Other findings
  • Irregular vertebral endplates
  • Schmorl nodes
  • Loss of disc space height
  • Scoliosis
  • Spondylolysis/spondylolisthesis
  • Disc herniation
  • Schmorl nodes: herniation of disc into vertebral endplate
• Cobb technique
  • Used to measure the angle between endplates
  • Use tilt angle of the end vertebral bodies that are most tilted in the kyphotic deformity, both proximally and distally on AP radiographs^[4]

MRI

• Can be useful to better evaluate soft tissue injuries
• Useful for pre-operative planning

CT

• Avoid if possible in the pediatric population

Other

• Consider checking pulmonary function tests to assess lung function

Classification

• Levels of involvement
  • Type I (Classic) – Thoracic spine involvement only, with the apex of curve T7-T9
    • Most common, better prognosis
  • Type II – Thoracic and lumbar involvement, with the apex of curve T10-T12
    • Less common
    • Associated with increased back pain, progression, severity
• Degree of hypnosis
  • Normal is 20° – 40°
  • Pathologic is > 40°
  • Around 95° can cause neurologic injury, myelopathy^[5]
  • Case reports of neurologic compromise as low as 53°^[6]
  • Curves > 100° can lead to restrictive lung disease^[7]

Treatment

Prognosis

• One-third of the patients with curves of 74° or more failed bracing and progressed to surgery^[8]
• Research shows 60-90% improvement of pain with surgery (need citation)
• Studies suggest residual curves >75° lead to worse functional outcomes (need citation)

Nonoperative

• Indications
  • Kyphosis less than 60°
  • Asymptomatic
• Medications
  • For short term relief
  • NSAIDS, Acetaminophen
• Activity modification
• Physical Therapy
  • Emphasis on stretching, core strengthening
• Extension bracing
  • Consider in patients with at least 45° of kyphosis, more commonly 60° – 80°
  • Options include Milwaukee Brace, Kyphologic Brace, Boston Brace
  • Anticipate approximately 50% correction with brace, slowing of progression
  • Compliance can be challenging
• Follow up
  • Annual follow up imaging should be obtained to monitor child

Operative

• Indications
  • Kyphosis > 75° with unacceptable deformity or pain
  • Neurological deficit or myelopathy
  • Refractory pain
• Technique
  • Smith-peterson osteotomy
  • Anterior release
  • Fusion