Because neither the degree of constriction of the spinal canal considered to be symptomatic for lumbar spinal stenosis nor the relationship between the clinical appearance and the degree of a radiologically verified constriction is clear, a correlation of patient's disability level and radiographic constriction of the lumbar spinal canal is of interest.

Osteotomies may be life saving procedures for patients with rigid severe spinal deformity. Several different types of osteotomies have been defined by several authors. To correct and provide a balanced spine with reasonable amount of correction is the ultimate goal in deformity correction by osteotomies. Selection of osteotomy is decided by careful preoperative assessment of the patient and deformity and the amount of correction needed to have a balanced spine. Patient's general medical status and surgeon's experience levels are the other factors for determining the ideal osteotomy type. There are different osteotomy options for correcting deformities, including the Smith-Petersen osteotomy (SPO), pedicle subtraction osteotomy (PSO), bone-disc-bone osteotomy (BDBO) and vertebral column resection (VCR) providing correction of the sagittal and multiplanar deformity. SPO refers to a posterior column osteotomy in which the posterior ligaments and facet joints are removed and a mobile anterior disc is required for correction. PSO is performed by removing the posterior elements and both pedicles, decancellating vertebral body, and closure of the osteotomy by hinging on the anterior cortex. BDBO is an osteotomy that aims to resect the disc with its adjacent endplate(s) in deformities with the disc space as the apex or center of rotational axis (CORA). VCR provides the greatest amount of correction among other osteotomy types with complete resection of one or more vertebral segments with posterior elements and entire vertebral body including adjacent discs. It is also important to understand sagittal imbalance and the surgeon must consider global spino-pelvic alignment for satisfactory long-term results. Vertebral osteotomies are technically challenging but effective procedures for the correction of severe adult deformity and should be performed by experienced surgeons to prevent catastrophic complications.

Our preliminary findings indicate that DTI may show abnormalities in the spinal cord before the development of T2 hyperintensity on conventional sequences in patients with CSM.

Fulcrum higher than bending higher than traction with the patient UGA is the order of radiographs for better predicting flexibility and correction in curves between 40 degrees and 65 degrees. Flexibility obtained at traction radiographs with the patient UGA is clearly better in numerical values, and closer to the amount of surgical correction than the amount of flexibility at fulcrum and side-bending radiographs for curves larger than 65 degrees, although not statistically significant as a result of the small number of patients in this group. However, pedicle screw instrumentation provides even more correction than the traction radiographs with the patient UGA. Thus, traction radiographs with the patient UGA may show much better flexibility, especially in more than 65 degrees and rigid curves.

Figure 1. Twenty-six years old female patient having postsurgical kyphosis after three previous operations. The preoperative and postoperative radiographs showed the correction of coronal and sagittal deformity after posterior vertebral column resection.Figure 2. Nine-year-old girl having previous in situ fusion and some kind of rib distraction device. PVCR was performed and the coronal and sagittal plane deformities were corrected. Spine www.spinejournal.com E343 DEFORMITY Posterior Vertebral Column Resection • Hamzaoglu et al