OBJECTIVETo analyze the possible reasons for proximal junctional lordosis (PJL) after short-segment posterior pedicle screw fixation in lumbar spine and discuss its proper management.

METHODSFrom December 2001 to August 2005, 345 patients were treated by short-segment pedicle screw fixation and these patients were reviewed. Clinical outcome was evaluated according to Oswestry Disability Index (ODI). Proximal junctional lordosis was assessed evaluated on radiographs, by measuring lumbar lordosis angle, segmental angle at proximal level and lumbar-sacral angle. Risk factors of proximal junctional lordosis were analyzed.

RESULTSAll patients were followed-up for 2 to 6 years (average 3.8 years). ODI after lumbar surgery was 9.7-46.2 ( average 19.6 +/- 10.7). PJL was noted in 78 patients (22.6%), 37 (10.7%) of whom were symptomatic and 21 (6.1%) received revision surgery. PJL was more commonly occurred in patients over 60 years old, with reduced lumbar lordosis or vertical sacrum. The number of fusion-segment was not correlated to the occurrence of PJL.

CONCLUSIONSShort-segment posterior pedicle screw fixation can not improve lumbar sagittal alignment. Age over of 60 years, reduced lumbar lordosis and vertical sacrum are possible risk factors of PJL sacrum.

Adult ; Aged ; Bone Screws ; Female ; Follow-Up Studies ; Humans ; Internal Fixators ; Lordosis ; etiology ; Lumbar Vertebrae ; surgery ; Male ; Middle Aged ; Retrospective Studies ; Spinal Fusion ; adverse effects ; Treatment Outcome

PURPOSE: Anterior cervical discectomy and fusion (ACDF) has become a common spine procedure, however, there have been no previous studies on whole spine alignment changes after cervical fusion. Our purpose in this study was to determine whole spine sagittal alignment and pelvic alignment changes after ACDF. MATERIALS AND METHODS: Forty-eight patients who had undergone ACDF from January 2011 to December 2012 were enrolled in this study. Cervical lordosis, thoracic kyphosis, lumbar lordosis, sagittal vertical axis (SVA), and pelvic parameters were measured preoperatively and at 1, 3, 6, and 12 months postoperatively. Clinical outcomes were assessed using Visual Analog Scale (VAS) scores and Neck Disability Index (NDI) values. RESULTS: Forty-eight patients were grouped according to operative method (cage only, cage & plate), operative level (upper level: C3/4 & C4/5; lower level: C5/6 & C6/7), and cervical lordosis (high lordosis, low lordosis). All patients experienced significant improvements in VAS scores and NDI values after surgery. Among the radiologic parameters, pelvic tilt increased and sacral slope decreased at 12 months postoperatively. Only the high cervical lordosis group showed significantly-decreased cervical lordosis and a shortened SVA postoperatively. Correlation tests revealed that cervical lordosis was significantly correlated with SVA and that SVA was significantly correlated with pelvic tilt and sacral slope. CONCLUSION: ACDF affects whole spine sagittal alignment, especially in patients with high cervical lordosis. In these patients, alteration of cervical lordosis to a normal angle shortened the SVA and resulted in reciprocal changes in pelvic tilt and sacral slope.
Adult ; Aged ; Cervical Vertebrae/physiopathology/radiography/*surgery ; Cross-Sectional Studies ; *Diskectomy ; Female ; Humans ; Lordosis/etiology/*surgery ; Magnetic Resonance Imaging ; Male ; Middle Aged ; Neck/surgery ; Retrospective Studies ; Spinal Diseases/complications/physiopathology/radiography/*surgery ; Spinal Fusion/*methods ; Spine ; Treatment Outcome ; Young Adult