Abstract
Introduction
The spinous process is commonly resected during posterior fusion of adolescent idiopathic scoliosis (AIS) to allow for a wider fusion bed and more local autologous bone graft. However, the spinous process is an important structure in the posterior ligament complex and anchors paraspinal muscles. With the development of pedicle screw instrumentation and the potential fusion ability in adolescents, the need for resecting the spinous process in this procedure should be further investigated. The purpose of this study is to compare the fusion rate, duration of surgery, blood loss, surgical outcomes and complications between harvesting and preserving the spinous process in posterior spinal fusion of AIS.
Material and Methods
From January 2003 to December 2008, 104 consecutive AIS patients who underwent primary posterior fusion with local autologous bone grafts and who were followed for a minimum of 24 months were reviewed. The patients were divided into a harvesting group (n = 61) who had the spinous process harvested, and a preserving group (n = 43) who had the spinous process preserved. Radiographic assessments of structural curves were reviewed pre-operatively, 3 days, and 3 and 6 months post-operatively, and then annually. Blood loss, duration of surgery, pseudoarthrosis, post-operative back pain and other complications were also recorded at these time points and compared between the two groups.
Results
There were no significant differences in the duration of surgery between the harvesting and preserving groups (216 ± 47 versus 224 ± 50 minutes, p = 0.40), however blood loss was significantly higher in the harvesting group was statistically higher (983 ± 446 ml) than in the preserving group (824 ± 361 ml; p = 0.048). The pre- and post-operative Cobb angles, correction rates, and loss of correction of the structure curves were similar in both groups. Based on radiographic evaluation, the incidence of pseudoarthrosis was similar in both groups (3/58 versus 2/41; p = 0.95). Post-operative back pain or soreness was significantly higher in the harvesting group (16/58 versus 4/43; p = 0.03).
Conclusion
The surgical outcomes and fusion rates between harvesting and preserving the spinous process were comparable, despite significantly lower blood loss and less back pain or soreness in the preserving group. Thus, resecting the spinous process as local autologous bone graft may not be necessary in posterior fusion for AIS patients.