OBJECTIVE Dynesys® is one of the pedicle-based dynamic lumbar stabilization systems and good clinical outcome has been reported. However, the cylindrical spacer between the heads of the screws undergoes deformation during assembly of the system. The pre-strain probably change the angle of instrumented spine with time and oblique-shaped spacer may reduce the pre-strain. We analyzed patients with...

OBJECTIVE We sought to determine minimum 4 years of clinical outcomes including fusion rate, revision rate and complications of patients who underwent placement of rectangular stand-alone cages. METHODS Thirty-three cases of degenerative spine that had been followed for at least 4-years were reviewed retrospectively. Cages were inserted at L4-L5 level or L5-S1 in 27 or in 6 cases respectively...

Introduction Posterior lumbar interbody fusion can theoretically allow neural decompression directly and by restoration of disc height and appropriate lumbar lordosis. The technique of insertion of a trapezoidal lordotic wedge spacer (ramp) into the disc space before rotating it into position theoretically will obtain both an increase in disc height and allow correction of lordosis. However obs...

ABSTRACT Objective: Rate and compare radiographic measurements of thoracic kyphosis lumbar lordosis using anatomical dynamic parameters. Methods: Measurements were performed on lateral radiographs 10 adults both sexes without spinal disease or deformity. Thoracic measured parameters (T1-T12, T4-T12, T5-T12 L1-S1) (cervicothoracic thoracolumbar inflection point). Results: different in 30% subjec...

Figure 1 Pelvic radiograph shows fusion of both sacro-iliac joints. Whiskering is present at both ischial tuberosities and rami (arrowheads). Irregularity and sclerosis of the lesser trochanters are arrowed. Hipjoints are concentrically narrowed. chronic low back pain and stiffness, of gradual onset, for 10 years. He was living in China previously, receiving herbal applications and pain killers...

Material and methods Twenty-five female patients with ASD (mean age 64.3 years) who underwent fusion surgery were included for analysis. Diagnosis was lumbar scoliosis in 10 patients, kyphoscoliosis in 11, and kyphosis in 4. Radiographic measurement of spinal alignment and CSA of lumbar trunk muscles including psoas major and lumbar extensor muscles measured by Magnetic Resonance Imaging (MRI) ...

STUDY DESIGN Retrospective study. PURPOSE To compare initial fixation using the cortical bone trajectory (CBT) technique versus conventional pedicle screws (PS) in radiographs of postsurgical lumbar degenerative spondylolisthesis. OVERVIEW OF LITERATURE Few reports have documented the holding strength of CBT technique for spondylolisthesis cases. METHODS From October 2009 to June 2014, 21...

BACKGROUND Dynamic interspinous stabilization devices generally provide satisfactory results, but can result in recurrent lumbar disc herniation, spinous process fracture, or bone resorption of the spinous process. The purpose of this study was to investigate if the Wallis dynamic stabilization device is associated with bone resorption. METHODS Patients who underwent single-segment posterior ...

The most common cause of iatrogenic flatback syndrome is Harrington distraction instrumentation extending into the lower lumbar spine. Other common causes and exacerbating factors include failure to enhance regional lordosis during lumbar fusion for degenerative spondylosis, development of pseudarthrosis or postoperative loss of correction, development of kyphosis at the thoracolumbar junction,...

The double S shape of the vertebral column is one of the most important evolutionary adaptations to human bipedal locomotion, providing an optimal compromise between stability and mobility. It is commonly believed that a six element long lumbar spine facilitated the critical adoption of lumbar lordosis in early hominins, which contrasts with five lumbars in modern humans and four in chimpanzees...