OBJECTIVETo evaluate the outcomes of selective anterior thoracolumbar or lumbar (TL/L) fusion for adolescent idiopathic scoliosis (AIS) with PUMCIId1 curves (Lenke type 5).

METHODSThirty-five consecutive AIS patients (PUMC type IId1, Lenke type 5) with selective anterior TL/L fusion with single solid rod instrumentation were reviewed. The average follow-up was 36 months (range, 18 - 42 months). Standing anteroposterior and lateral radiographs were measured and analyzed.

RESULTSThe average preoperative Cobb angle of the TL/L curves was 45.6 degrees and corrected to 9.7 degrees postoperatively, with 79.7% curve correction. The thoracic curves decreased from 29.7 degrees preoperatively to 17.6 degrees postoperatively, with a spontaneous correction of 41.5%. There was an average 4.7 degrees and 2.5 degrees correction loss of the TL/L and the thoracic curves at the final follow-up respectively. Trunk shift deteriorated slightly from 14.0 mm preoperatively to 14.8 mm postoperatively, and improved significantly to 5.1 mm at the final follow-up. The lowest instrumented vertebra (LIV) tilt was significantly improved after surgery (from -21.8 degrees preoperatively to -1.5 degrees postoperatively) and well maintained at the final follow-up (-2.1 degrees). The coronal disc angle immediately above the upper instrumented vertebra (UIVDA) and below the LIV (LIVDA) averaged 0.5 degrees and 0.6 degrees respectively, and aggravated after surgery (0.9 degrees and 4.9 degrees, respectively). Both the UIVDA and LIVDA were significantly aggravated at the final follow-up (3.0 degrees and 7.8 degrees, respectively). The sagittal contours of T(5-12) and T(10)-L(2) were well maintained after surgery and at the final follow-up. The lumbar lordosis of L(1)-S(1) and the sagittal Cobb angle of the instrumented segments were reduced postoperatively and at the final follow-up. No pseudarthrosis or other complications were observed.

CONCLUSIONSelective anterior TL/L fusion with single solid rod instrumentation is effective and safe for AIS with PUMCIId1 (Lenke type 5) curves, above and below the fusion and larger residual thoracic curve in some cases need further evaluated.