Prediction of thoracic dimensions and spine length based on individual pelvic dimensions in children and adolescents: an age-independent, individualized standard for evaluation of outcome in early onset spinal deformity.

STUDY DESIGN: A retrospective review of spine, chest, and pelvic dimensions of normal CT scans from 1999 to 2004 was performed. OBJECTIVE: To determine age-independent predictors of spine and chest dimensions. SUMMARY OF BACKGROUND DATA: Progressive thoracic deformity is associated with early-onset spinal deformities. Patients with severe early-onset scoliosis are commonly smaller and slower to grow than normal. Newer treatment approaches emphasize spine length and chest growth. Assessing treatment outcomes is hampered by the lack of normal values appropriate for diseased children. This study establishes normal range standards of chest and spine dimensions to aid in assessment of treatment outcomes. METHODS: A total of 198 CT scans of previously healthy patients 0 to 21 years of age were measured. Measurements taken from CT scans include maximum inner chest width, anteroposterior chest depth, thoracic spine height, lumbar spine height, total spine height, and pelvic inlet width. Linear regression was applied to establish gender-specific reference ranges for spine and chest dimensions based on pelvic width. RESULTS: Chest and spine dimensions were significantly correlated with pelvic inlet width and gender (P < 0.001). Multiple linear regression indicated that pelvic inlet width provided excellent fit in establishing gender-specific normal ranges independent of age. CONCLUSION: Pelvic inlet width is an age-independent predictor of pediatric chest width and thoracic dimensions that may be used to assess thoracic and spine growth in early onset spine deformity patients.

The treatment of spine and chest wall deformities with fused ribs by expansion thoracostomy and insertion of vertical expandable prosthetic titanium rib: growth of thoracic spine and improvement of lung volumes.

STUDY DESIGN: Prospective clinical trial of vertical expandable prosthetic titanium rib (VEPTR) in patients with combined spine and chest wall deformity with scoliosis and fused ribs. OBJECTIVE: Report the efficacy and safety of expansion thoracostomy and VEPTR surgery in the treatment of thoracic insufficiency syndrome (TIS) associated with fused ribs. SUMMARY OF BACKGROUND DATA: Traditional attitudes toward early-onset combined chest and spine deformity assume that thoracic deformity is best controlled by treatment directed at spine deformity, often involving early spinal arthrodesis. Campbell and others have heightened awareness of the interrelationship between lung, chest, and spine development during growth and characterized TIS as the inability of the thorax to support normal respiration or lung growth. Expansion thoracostomy and VEPTR insertion was developed to directly control both spine and chest wall deformity during growth, while permitting continued vertebral column and chest growth at an early stage. METHODS: Multidisciplinary evaluation of children with combined spine and chest wall deformity included pediatric pulmonologist, thoracic, and orthopedic surgeon evaluations. One or more opening wedge expansion thoracostomies and placement of VEPTR devices were performed as described by Campbell, with repeated device lengthenings during growth. Parameters measured included Cobb angle, length of thoracic spine, CT-derived lung volumes, and in older children pulmonary function tests. RESULTS: Thirty-one patients with fused ribs and TIS were treated, 4 of whom had undergone prior spinal arthrodesis at other institutions with continued progression of deformity. In 30 patients, the spinal deformity was controlled and growth continued in the thoracic spine during treatment at rates similar to normals. Increased volume of the constricted hemithorax and total lung volumes obtained during expansion thoracostomy were maintained at follow-up. Complications included device migration, infection, and brachial plexus palsy. CONCLUSIONS: Expansion thoracostomy and VEPTR insertion with serial lengthening may be the preferred treatment for young children with chest wall deformity and scoliosis associated with fused ribs but requires multidisciplinary care and attention to details of soft tissue management. When indicated, surgical intervention with VEPTR can be considered early in growth, before deformity is severe, since spinal growth will continue with treatment.