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Thoracic Insufficiency Syndrome
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Laura Stoll
November 2010
Normal thorax
• Spine + rib cage + sternum + diaphragm
• Lung development depends on thoracic
growth
– Increase in T-spine height
– Symmetrical enlargement of rib cage through
rib growth
– Correct orientation of ribs
Thoracic spine growth
• Birth-5 years: 1.4 cm/yr
• 6-10 years: 0.6 cm/yr
• 11-15 years: 1.2 cm/yr
• Marked loss of T-spine height = severe
reduction in thoracic volume for lungs
• Jarcho-Levin syndrome (spondylothoracic
dysplasia)
– Single, short, block vertebra (1/4th normal height)
– High mortality due to respiratory complications
Campbell RM, et al 2007; Ramirez N, et al
Rib contribution
• Birth - 2 years:
– Ribs horizontal = growth of rib in length
– Increase in diameter of rib cage = square-shaped
thoracic cross-section
• 2 years-10 years:
– Rib course downward = oval-shaped thoracic
cross-section
• 10 years - skeletal maturity:
– Ribs grow rapidly = final rectangular shaped
thoracic cross-section
• Rib cage contributes to volume increase
by expanding anteriolaterally “buckethandle” biomechanism
• Diaphragm “piston” increases thoracic
volume by downward excursion
Thoracic insufficiency
syndrome
• Inability of the thorax to support normal
respiration or lung growth
• Thoracic insufficiency syndrome does
not equal respiratory insufficiency
• Dx based on H&P, imaging studies, V-P
lung scans, PFTs, labs
Campbell RM, et al 2003
Disorders of normal, stable
thorax volume
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Causes extrinsic restrictive lung disease
Scoliosis with absent or fused ribs
Scoliosis with windswept deformity
Jarcho Levine syndrome
Jeune syndrome
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Disorders of thorax’s ability to
change volume
• CDH - decreased contraction of
diaphragm
• Unilateral hemidiaphragm paralysis
• Anomalous insertion of the diaphragm
in congenital scoliosis and rib anomalies
• Secondary thoracic insufficiency
syndrome - torso collapsed on pelvis
Campbell RM, et al 2004
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Campbell RM, et al 2007
• Standard scoliosis:
– Thorax usually spacious, no rib cage
deformities, near normal vital capacity
– Characterized by degree of curve on AP
radiographs
– Tx: bracing or definitive spinal fusion
Exotic scoliosis
• Early onset
• Thorax distorted by spinal lordosis and curve
rotation
• Often associated with rib-cage deformities:
absent or fused ribs
• Volume depletion deformity and thoracic
growth inhibition = adverse effects on lung
growth
• Can’t do conventional treatments
(fusion):
– Bone stock may be insufficient
– Patient too small for standard implants for
fusion
– Lung function may be too poor
– Will not address the 3D thoracic deformity
– Loss of growth of T-spine from early fusion
would impact thoracic volume
VEPTR
• Vertical expandable
prosthetic titanium rib
• Dr. Robert Campbell
and Dr. Melvin Smith of
Christus Santa Rosa
Children’s Hospital in
San Antonio, TX
• Received FDA approval
in August 2004
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Surgical Indications
• Rib fusion and progressive scoliosis
• Hypoplastic thorax syndrome
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Jeune’s syndrome
Achondroplasia
Jarcho-Levin syndrome
VACTERL syndrome
• Flail chest syndrome
– Rib agenesis
– Acquired causes
Type I: Absent ribs and
scoliosis
• Stabilization expansion thoracoplasty
– Stabilizes the flail chest-wall segment
– Laterally expands and lengthens the
collapsed hemithorax section
• 2-3 VEPTR devices used
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Campbell RM, et al 2007
Type II - fused ribs and
scoliosis
• Opening wedge thoracostomy
• Fused hemithorax is osteotomized
transversely, lengthened until the thorax
is equilibrated
• Those under 2 years old with no history
spine surgery do best
Campbell RM, et al 2007
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Campbell RM, et al 2007
Type IIIa - Jarcho-Levin
Syndrome
• Staged bilateral opening-wedge
thoracostomies
• Rib-to-rib VEPTR devices
• Lengthen sequentially constricted
hemithorax while correcting any
associated scoliosis
Campbell RM, et al 2007
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Campbell RM, et al 2007
Type IIIb - Jeune syndrome or infantile
scoliosis with windswept deformity
• Circumferential thoracic constriction
• Staged bilateral dynamic segmental curved
VEPTR
• In windswept deformity scoliosis, concave
chest is lengthened with opening-wedge
thoracostomy, lengthening of hemithorax,
stabilization with unilateral rib to spine or rib
to pelvis VEPTR
Campbell RM, et al 2007
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VEPTR complications
• Prone to complications due to repetitive
nature of maintenance surgeries
– Wound infection - 3.3% per procedure
– Skin slough
– Scarring
• Migration of fixation - 0.09 migrations/yr/pt
• Device breakage
• Brachial plexus injuries
Campbell RM, et al 2007
Outcomes
• Improvement of percentile weight
• Decreased in ventilator dependence, increase
in thoracic volume
• +/- increase in lung volume (and decrease in
FVC) - benefit may lie more in stabilizing
thorax and improving respiratory mechanics
measured in other ways
• 10/21 patients had increased activity levels
postoperatively
Skaggs, et al; Campbell RM, et al 2007; Yazici, et al;
Mayer, et al; Waldhausen, et al
• Further defining thoracic insufficiency
syndrome
• VEPTR new device. Long term followup studies still needed
References
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Campbell RM, et al. JBJS Am. 2003;85:399
Campbell RM, et al. JBJS Am. 2004;86:1659
Campbell RM, et al. JBJS Am. 2004;86Suppl1:51
Campbell RM, et al. JBJS Am. 2007;89-A:108
Mayer, et al. J Pediatr Orthop. 2009;29:35
Rameriz N, et al. JBJS Am. 2007;89:2663
Skaggs, et al. Spine. 2009;34:2530
Waldhausen JHT, et al. J Pediatr Surg. 2007;42:76
Yazici, et al. Spine. 2009;34:1800