STUDY DESIGN: A retrospective evaluation of 203 adolescent idiopathic @entity1635 @entity1 with Lenke 1B or 1C (King-Moe II) type curves. OBJECTIVES: To evaluate the incidence of inclusion of the lumbar curve in the treatment of this @entity85 as well as radiographic factors associated with lumbar curve fusion. SUMMARY OF BACKGROUND DATA: In @entity1 with @entity2383 , many authors have recommended fusing only the thoracic curve (selective thoracic fusion). Studies have shown that correction of the thoracic curve results in spontaneous correction of the unfused lumbar curve; however, in some cases, truncal decompensation develops. Though there have been various attempts to define more accurately what type of curve pattern should undergo selective fusion, controversy continues in this area. METHODS: Measurements were obtained from the preoperative standing posteroanterior and side-bending radiographs of 203 @entity1 with Lenke Type 1B or 1C curves from five sites of the DePuy AcroMed Harms Study Group. @entity1 were divided into two groups depending on their most distal vertebra instrumented: the "selective thoracic fusion" group included @entity1 who were fused to L1 or above and the "nonselective fusion" group included @entity1 fused to L2 or below. A statistical comparison was conducted to identify variables associated with the choice for a nonselective fusion. RESULTS: The incidence of fusion of the lumbar curve ranged from 6% to 33% at the different @entity1 care sites. Factors associated with nonselective fusion included larger preoperative lumbar curve magnitude (42 +/- 10 degrees vs. 37 +/- 7 degrees, P < 0.01), greater displacement of the lumbar apical vertebra from the central sacral vertical line, (3.1 +/- 1.4 cm vs. 2.2 +/- 0.8 cm, P < 0.01), and a smaller thoracic to lumbar curve magnitude ratio (1.31 +/- 0.29 vs. 1.44 +/- 0.30, P = 0.01). CONCLUSIONS: The characteristics of the compensatory "nonstructural" lumbar curve played a significant role in the surgical decision-making process and varied substantially among members of the study group. Side-bending correction of the lumbar curve to <25 degrees (defining these as Lenke 1, @entity2649 ) was not sufficientcriteria to perform a selective fusion in some of these cases. The substantial variation in the frequency of fusing the lumbar curve (6% to 33%) confirms that controversy remains about when surgeons feel the lumbar curve can be spared in Lenke 1B and 1C curves. Site-specific analysis revealed that the radiographic features significantly associated with a selective fusion varied according to the site at which the @entity1 was treated. The rate of selective fusion was 92% for the 1B type curves compared to 68% for the 1C curves.

Factors involved in the decision to perform a selective versus nonselective fusion of Lenke 1B and 1C (King-Moe II) curves in adolescent idiopathic XXXX .

@entity1 :: ('9606', 'Species') :: ['Patients', 'patients', 'patient'] @entity2649 :: ('MESH:C563613', 'Disease') :: ['nonstructural lumbar curves'] @entity1635 :: ('MESH:D012600', 'Disease') :: ['scoliosis'] @entity85 :: ('MESH:D009140', 'Disease') :: ['type of deformity'] @entity2383 :: ('MESH:D028361', 'Disease') :: ['structural thoracic curves and compensatory lumbar curves']
@entity1635 :: (MESH:D012600,Disease) :: ['scoliosis']
