Strategies for the treatment of severe and progressive scoliosis in children have traditionally involved consideration of an instrumented spinal fusion procedure. In the short-term, these procedures offer predictable outcomes for the majority of patients, including achievement of a spinal fusion, prevention of scoliosis progression, and substantial correction of spinal deformity. However, a spinal fusion procedure is a salvage-type surgery that eliminates growth, motion, and function in the fused portion of the spine. Although safe and effective in the short-term, the implications of a multisegment spinal fusion may not be benign in the long-term for all patients. This is particularly true for children at the extremes of age and curve severity. For young children with progressive scoliosis, fusion procedures may result in a short trunk deformity and/or thoracic insufficiency syndrome. For older children, fusion procedures may eventually result in painful adjacent segment degeneration or spinal imbalance issues.
The limitations of spinal fusion surgery have prompted investigators to seek more physiologic solutions for these deformities. The alternatives for surgical treatment of spinal deformity can be categorized as involving: 1) limited fusion (e.g., hemiepiphysiodesis, short segment fusion); 2) temporizing measures that delay fusion (e.g., growing rods, VEPTR); and even 3) fusionless scoliosis surgery that avoids fusion (e.g., anterior vertebral stapling, anterior thoracic tethering). The goal of each of these treatment options is to preserve as much growth, motion, and function of the spine as possible. Temporizing measures that prevent deformity progression in a young child potentially allow additional vertical spinal growth, chest volume expansion, and continued pulmonary development. Although fusion is eventually required in these children, the long-term impact on morbidity, as well as the avoidance of mortality issues associated with extensive spinal fusion in the very young child, is significant. The impact of fusionless procedures in the older child may be less dramatic. However, in the short-term, these potentially offer a single, definitive, minimally invasive (or at least less extensive) procedure, without requirement for bone graft or achievement of fusion. In the long-term, the preservation of growth, motion, and function of the spine also may reduce the risk of painful adjacent segment degeneration and spinal imbalance issues.
The papers in this section discuss some of the more novel approaches to the treatment of progressive spinal deformities in children. For the temporizing measures that involve the use of growing rods or VEPTR, useful clinical data are provided from investigators with substantial experience in treating scoliosis in the young child. For the more definitive fusionless treatments, involving stapling or tethering of the spine to guide growth, extensive data from animal testing are provided in the hope that this will allow optimal application of these techniques in children.