Transverse plane pelvic rotation: AIS Double Curve
Transverse plane pelvic rotation increase (TPPRI) following rotationally corrective instrumentation of adolescent  idiopathic scoliosis double curves   Marc A  Asher, Sue-Min Lai, Brandon B Carlson, Jeffrey L Gum and Douglas C Burton   Background   We have occasionally observed clinically noticeable  postoperative transverse plane pelvic rotation increase (TPPRI) in the  direction of direct thoracolumbar/lumbar rotational corrective load  applied during posterior instrumentation and arthrodesis for double  (Lenke 3 and 6) adolescent idiopathic scoliosis (AIS) curves.  Our  purposes were to document this occurrence; identify its frequency,  associated variables, and natural history; and determine its effect upon  patient outcome.   Methods   Transverse plane pelvic rotation (TPPR) can be quantified  using the left/right hemipelvis width ratio as measured on standing  posterior-anterior scoliosis radiographs.   Descriptive statistics were  done to determine means and standard de...