The Effect of Concomitant Rib Deformity in Congenital Scoliosis on Spinal Curve Correction After Segmental Pedicle Screw Instrumentation.

STUDY DESIGN: A single-center, prospective study.

OBJECTIVE: To investigate the effect of rib anomaly on surgical curve correction outcome in congenital scoliosis.

SUMMARY OF BACKGROUND DATA: The presence of rib anomalies may complicate surgical correction of congenital scoliosis. The outcome of surgical correction, however, has not been documented in scoliotic patients with and without rib deformity.

METHODS: Percent Cobb angle decrease (CAD) after operation was calculated in 94 patients with congenital scoliosis. Posterior segmental pedicle screw instrumentation (posterior approach) with or without previous anterior spinal release and fusion (anterior approach) was the method of correction. The impact of vertebral anomaly and rib deformity on CAD was examined.

RESULTS: Although the type of vertebral anomaly had no significant effect on the mean CAD, it was significantly lower in 56 patients with rib deformity compared with that in the remaining patients without rib deformity (35.14%±15.83% vs. 51.54%±17.82%, P<0.001); particularly in those with complex, unilateral rib abnormalities, and in those with same-level vertebral and rib deformities. Patients' sex and age at the time of operation, rib number abnormality, and the type of operation (ie, posterior-only approach vs. anterior and posterior approach) did not contribute significantly to Cobb angle change after operation.

CONCLUSIONS: Concomitant rib deformities, particularly of complex and unilateral types, significantly compromise operative curve correction outcome in congenital scoliosis.