The progression of lumbar curves in adolescent Lenke 1 scoliosis and the distal adding-on phenomenon

Abstract

4, retrospective study.

Distal adding-on phenomenon in adolescent idiopathic scoliosis patients with thoracolumbar vertebra fusion

“…Thus, several authors have focused on this phenomenon and have found that skeletal immaturity and the selection of the LIV are highly correlated with distal adding-on. [ 1 , 4 , 8 ] Skeletal immaturity is indicated by an earlier and smaller Risser sign. Risser sign is the most common method to predict the development degree of AIS patients.…”

“…Matsumoto et al [ 3 ] suggested that the remaining apical vertebra deviation of the main thoracic curve and the last touching vertebra (LTV) in the cephalad direction of the LIV were significantly correlated with adding-on. Lakhal et al [ 4 ] concluded that the choice of the LIV influenced the deterioration of the lumbar curve and the development of adding-on.…”

“…Although many risk factors have been found, the incidence of adding-on is low, ranging from 2% to 13%. [ 2 – 4 ] We generally believe that some cases of adding-on may be avoided. As found in clinical observation, the relationship between the CSVL and the LIV has an important guiding significance for the choice of the LIV.…”

“…However, in surgical cases, after spinal fusion control, the deformity continues to develop, and the spine continues to grow, thus producing the distal postoperative adding-on phenomenon. [ 1 ] Adding-on often leads to the progressive loss of curve correction, unsatisfactory clinical outcomes, and a high risk of reoperation, the incidence of which has been reported to be 2% to 13% [ 2 – 4 ] and is a great concern among patients and surgeons. [ 5 ]…”

“…Many previous studies have focused on this phenomenon. Although many risk factors are associated with adding-on, such as age, skeletal immaturity, increases in the lowest instrumented vertebrae-central sacral vertical line (LIV-CSVL) distance of 10 mm in the postoperative period, the number of vertebrae from the first nonfused vertebra to the L5 vertebra (Dnfs), the postoperative scoliosis of the lumbar curve, and shoulder balance, [ 3 , 4 , 6 – 8 ] the selection of the LIV is the most important factor. Wang et al [ 1 ] suggested choosing the DV (the first vertebra in the cephalad direction from the sacrum with a deviation from the CSVL of more than 10 mm) because the LIV may provide the best outcome; it not only prevents adding-on but also conserves more lumbar motion and growth potential.…”