STUDY DESIGN. Prospective clinical study. OBJECTIVE. To investigate if a correlation exists between various parameters including major thoracic curve correction and postoperative pulmonary function test (PFT) improvement at 2 years postoperative following posterior segmental spinal fusion (PSSF) and instrumentation with iliac crest bone graft (ICBG). SUMMARY OF BACKGROUND DATA. There are no studies available on the correlation between major thoracic curve correction and postoperative PFT improvement following PSSF and instrumentation with ICBG with a homogenous diagnosis, similar operation method, and similar age population. METHODS. One hundred thirty-nine patients with adolescent idiopathic scoliosis (Lenke type 1-4), undergoing PSSF and instrumentation with ICBG at a single institution, were before surgery and 2 years after surgery prospectively evaluated in regard to PFTs, assessing forced vital capacity, and forced expiratory volume in 1 second. PFTs change at 2 years postoperative was compared by the various parameters including major thoracic Cobb curve correction and the types of instrumentation. We defined a significant clinical improvement as a 10% or more increase of percent predictive FEV1 value at 2 years postoperative. RESULTS. PSSF and instrumentation with ICBG demonstrated statistically significant improvement of absolute and percent-predicted PFTs at 2 years postoperative. There was a significant clinical improvement in 31 patients (22%) at 2 years postoperative. Significant clinical improvement was related to thoracic pedicle screw instrumentation (vs. thoracic hook instrumentation, P = 0.030). Absolute amount of major thoracic Cobb correction, magnitude of the residual curve, correction percentage of the major thoracic Cobb, the number of fused vertebrae, Risser sign, and age at surgery did not demonstrate any significant positive or negative correlation (-0.3 <Pearson correlation coefficient <0.3). CONCLUSIONS. Patients having a PSSF and instrumentation with ICBG statistically significant improvement of absolute and percent-predicted PFTs at 2 years postoperative. There was a significant clinical improvement in 31 patients (22%) at 2 years postoperative. A significant clinical improvement was related with thoracic pedicle screw instrumentation.
- Adolescent idiopathic scoliosis
- Iliac crest bone graft
- Major Cobb correction
- Posterior segmental spinal fusion
- Pulmonary function test