Surgical outcomes of anterior instrumentation and fusion for Lenke 5 AIS: a comparison between the left and right curve

English Keywords:Adolescent idiopathic scoliosis  Correction rate  Loss of correction  Outcome

English Abstract:

  【Abstract】 Objectives: To investigate the influence of curve direction on surgical outcomes of anterior single-rod instrumentation and fusion for Lenke 5 adolescent idiopathic scoliosis(AIS). Methods: A retrospective review was performed on 52 patients who underwent surgery for Lenke 5 AIS at our clinic between January 2005 and December 2009. According to the direction of thoracolumbar/lumbar(TL/L) curve, the patients were divided into the left-sided group(group L, n=38) and the right-sided group(group R, n=14). The radiographic measurements were compared between the two groups at preoperation, postoperation and follow-up by using the Student′s t test: curve magnitude, coronal balance, thoracic kyphosis, thoracolumbar junctional angle, lumbar lordosis, sagittal vertical axial, and so on. Results: Preoperative Cobb angles of the TL/L and thoracic curves as well as the number of levels in TL/L curve were comparable between the two groups. Duration of follow-up for group L and R averaged 3.1±0.9 years and 2.7±0.8 years, respectively. Compared with group L, operation time and intraoperative blood loss were both found to be higher in group R though not reaching statistical significance(208.8±41.4min vs. 225.6±39.6min, P=0.132; 236.5±159.6ml vs. 284.4±164.7ml, P=0.345). The average TL/L curve correction was 66.7% in group L and 64.4% in group R(P=0.808), and at final follow-up, the loss of TL/L curve correction averaged 4.6% and 5.1%, respectively(P=0.992). With respect to the thoracic curve, the average correction and correction loss at final follow-up were found to be similar between the two groups(P=0.886 and P=0.759, respectively). Complications occurred in 4 of the patients, with one proximal junctional kyphosis and two distal adding-on presenting in group L, as well as one proximal adding-on in group R. There was no neurologic complication, vascular injury or implant failure noted untill final follow-up. Conclusions: Anterior single-rod instrumentation remains an effective surgical treatment for Lenke type 5 AIS, and there is no statistically significant difference comparing the left and the right TL/L curves.