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Scoliosis Surgery:
Complications
Tamara Simon, M.D.
July 2004
Scoliosis: Definition
• Scoliosis: lateral displacement or curvature of the
spine, usually occurs with• Kyphosis: spinal deformity with anteroposterior
angulation (can occur in isolation , from
destruction or injury to the vertebral bodies)
• Severity of these two conditions is defined by
measurement of the Cobb angle of curvature that
is formed by the limbs of the convex primary
curvature
Cobb Angle
Causes of Kyphoscoliosis
• Idiopathic (80%)
• Neuromuscular disease
– Muscular dystrophy
– Polio
– Cerebral palsy
• Vertebral disease
–
–
–
–
Osteoporosis/ osteomalacia
Pott’s disease
Neurofibromatosis
Rickets
• Disorders of connective tissue
– Marfan’s syndrome
– Ehlers-Danlos syndrome
– Morquio’s syndrome
• Acquired abnormalities
– Thoracoplasty
– Fibrothorax
Diagnosis/ Prognosis
• Diagnosis is made by physical examination
• Extent is often underestimated until
radiographs are visualized
• Degree of spinal deformity is the most
important risk factor for respiratory failure,
and the effects of kyphosis and scoliosis are
additive
Pathophysiology
• PFTs demonstrate a restrictive pattern usually, with
decreased TLC, VC, FRC, and compliance (effects of
breathing at low lung volumes)
• ABG demonstrates hypoxemia without hypercapnia is seen
in moderate to severe disease; V/Q mismatch has been
reported with a scoliosis angle greater than 65 degrees
• Pulmonary hypertension can develops as a result of
persistent hypoxemia
• Nocturnal hypoventilation and arterial oxygen desaturation
are described during REM.
• Exercise limitation is often present in patients with
kyphoscoliosis. However, there is a normal breathing
pattern response to exercise and a normal maximum tidal
volume to vital capacity ratio. Hence, exercise intolerance
may be a result of physical deconditioning
Treatment
• Mild disease has a good prognosis and requires
supportive care only
• In adults, surgery is of questionable benefit and
carries a significant complication rate
• In adolescents, both surgery and brace treatment
improve lung function.
• Medical therapy can include pulmonary
rehabilitation, supplemental oxygen as needed,
and managing ventilatory failure (i.e. negative
pressure ventilators, positive pressure ventilation
administered via tracheostomy, and more recently,
noninvasive positive pressure ventilation.
…or Surgery
A Standing PA XR of 6-year-old with
neurofibromatosis,
curve 38 degrees
B Standing PA XR. Despite bracing,
her curve increased to 67 degrees
C Patient has unresectable
neurofibroma occluding one lung, but
needs continued chest cavity growth
and lung expansion.
D Standing PA XR after dual growth
rods inserted, routine rod lengthening
6 months later. Curve is now 45
degrees.
Surgery: Early Complications in
PICU
• Coagulopathy
• Ileus (3.5% to 6.1%)
– Usually seen for 36-48 hours
• Fat embolism
– Tachycardia, tachypnea, altered mental status, pyrexia
– Release of fat into bloodstream after long-bone
procedures
• Pneumothorax
• Chylothorax
• Hemothorax
Surgery: Early Complications
(cont)
• SIADH (33% of children)
– Hyponatremia, hypoosmolality concentrated urine, normal renal
and adrenal function
– Excessive action of ADH in renal tubules; release of ANP
– Thought due to increased manipulation of dura and neural tracts as
well as blood loss
• Pancreatitis (14% of all patients)
– Persistent vomiting, abdominal pain, elevation of serum amylase
and lipase
– Inflammation of pancreatic tissue
– Thought related to positioning, ischemia, hypotension, etc.
Surgery: Late Complications
• Cholelithiasis
– Immediately post-op secondary to hemolysis coupled
with postoperative fasting
– Gallstones may persist for several years (11.1% by
ultrasound)- but not specific to scoliosis patients
– 50% are asymptomatic, less than 25% will require
intervention
– Present with acute cholecystitis (RUQ pain, guarding,
rebound tenderness, leukocytosis, and pyrexia)
Surgery: Late Complications
• Superior mesenteric artery syndrome
– Nausea, intermittent bilious vomiting, abdominal pain,
distention
– Due to extrinsic compression of third portion of
duodenum between SMA and aorta
– Associated with burns, anorexia, weight loss, tumors,
and spinal manipulation (usually patients are 20%
underweight)
– Reasons for association may include adolescent growth
spurt; upward tension on SMA root and
mesentery,decreasing SMA angle and compressing
duodenum; and relative spinal extension in scoliosis
creating more vertical tension on soft tissue anterior to
spine
Surgery: Late Complications
A characteristic UGI
series showing sharp
cutoff of contrast
material at the third
portion of the
duodenum (secondary
to compression by the
superior mesentery
artery)
References
• Barron RM, Schwarzstein RM. Diseases of the
Chest Wall, Up to Date
• Canale: Campbell's Operative Orthopaedics, 10th
ed., MD Consult
• Feldman: Sleisenger & Fordtran's Gastrointestinal
and Liver Disease, 7th ed., MD Consult
• Shapiro G, Green DW, Fatica NS, et al. Medical
complications in scoliosis surgery. Current
Opinion in Pediatrics, 2001, 13:36-41.