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Koji Otani

Publications and source records attributed to Koji Otani.

5 recordsLinked to original sources

Mid-term and long-term follow-up data after placement of the Graf stabilization system for lumbar degenerative disorders.

OBJECT: The Graf pedicle screw and ligament device is designed to provide flexible stabilization to prevent abnormal spinal movement. The purpose of this study was to investigate radiographic and clinical outcomes during a minimal 5-year follow-up period. METHODS: Between 1991 and 1997, 43 consecutive patients (whose mean age was 61 years) with lumbar degenerative disease underwent decompression and stabilization in which the Graf system was placed. Data were available for 31 patients who attended follow up for the minimal 5-year period. In a retrospective review, the authors assessed measurements on radiographs, clinical results (using Japanese Orthopaedic Association [JOA] Scale scores), and low-back pain (using a visual analog scale [VAS] score), preoperatively and postoperatively at 1, 3, 5, and/or 10 years. Radiographic measurements included sagittal and frontal range of motion (ROM), regional lordosis, and posterior disc height as well as the extent of degenerative spondylolisthesis. Final follow-up JOA and VAS scores were significantly better than preoperative scores. Sagittal and frontal ROM was significantly reduced at 1 and 5 years, respectively, compared with preoperative values, and a gradual reduction persisted throughout the follow-up period. Compared with its preoperative status, the disc height ratio (adjacent segments to the operated level) was reduced 5 years after surgery. A significant inhibition of the vertebral slippage was detected only in the flexion position. CONCLUSIONS: Analysis of these data indicated that the Graf system eventually leads to successful fusion, suggesting the presence of stability in all three dimensions. The use of the Graf system should continue to be evaluated as an alternative device in the treatment of lumbar degenerative disease.

Adult↗

[Block treatment for low back pain--technical note].

Many types of block are used for treatment of low back pain. In the current paper, trigger-point block, facet block, ilio-sacral joint block, epidural block and nerve root infiltration (nerve root block), quite common procedures for treatment of low back pain, are introduced and technical notes are described. There are two important points for block treatment, one is the knowledge of anatomy and another is the knowledge of side effects. We must remember to prepare everything for side effects when block treatment is done.

Humans↗

Indomethacin blocks the nucleus pulposus-induced effects on nerve root function. An experimental study in dogs with assessment of nerve conduction and blood flow following experimental disc herniation.

Inflammatory mechanisms have been suggested to be involved in the basic pathophysiologic events leading to nerve root injury after local application of nucleus pulposus. To assess if these nucleus pulposus-induced effects could be blocked by anti-inflammatory treatment, 41 dogs were exposed to either incision of the L6-7 disc to induce experimental disc herniation with (n=12) or without (n=14) indomethacin treatment per os (5 mg/kg per day), and no incision with (n=5) or without (n=10) indomethacin. Intraneural blood flow and nerve conduction velocity were assessed after 7 days to evaluate the degree of nerve injury. Disc incision induced a reduction in nerve root and dorsal ganglion blood flow as well as nerve function, similarly to previous studies. However, simultaneous treatment with indomethacin efficiently blocked the negative effects on both blood flow and nerve conduction but had no effects per se. The present study thus indicates that inflammatory mechanisms may be of relevance in the pathophysiology of nucleus pulposus-induced nerve root injury and thereby also for sciatica.

Animals↗

Correlation of low back pain with functional status, general health perception, social participation, subjective happiness, and patient satisfaction.

STUDY DESIGN: A cross-sectional and epidemiologic study investigated low back pain. OBJECTIVE: To assess the correlation among outcome measures for low back pain, including sciatica, according to a proposed low back pain-related model. SUMMARY OF BACKGROUND DATA: Various outcome measures are used in low back pain research: pain, functional status, generic health status, and patient satisfaction. Correlation among these measures has been unclear. METHODS: For this study, 816 subjects (369 men and 447 women; average age, 62 years) who underwent an adult medical examination. The patients were interviewed concerning their personal background, severity of low back pain and sciatica, functional status, general health perception, social participation, subjective happiness, and patient satisfaction. The correlation among these measures was analyzed systematically using path analysis based on a low back pain-related model hypothesizing that low back pain and sciatica worsen functional status and general health perception and then affect social participation, subjective happiness, and patient satisfaction. RESULTS: Restriction of functional status was found to be the most closely correlated with severity of low back pain. A decrease in physical health was most closely correlated with restriction of function. Social participation, subjective happiness, and patient satisfaction were closely correlated with physical health status. There was a significant correlation among outcome measures concerning physical health, which was consistent with a low back pain-related model. CONCLUSIONS: The outcome measures concerning physical health in this study were found to be correlated significantly, consistent with the proposed low back pain-related model.

Adult↗

Anatomic study of the axis for surgical planning of transarticular screw fixation.

Transarticular screw fixation has shown increased stability compared with other posterior stabilization techniques. However, there have been few reports on vertebral artery injury related to the screw insertion. The current study measured the parameters of the pedicle and vertebral artery groove of the axis and clarified the accuracy and safety of the transarticular screw fixation. Direct measurements were taken from 98 dry axis vertebrae. The width and height of the pedicle were measured. The mediolateral and anteroposterior dimensions of the vertebral artery groove also were measured. Forty-one percent had asymmetry. In 20% of the specimens, the pedicle was smaller than the diameter of the screw (3.5 mm). The pedicle of the axis has large anatomic variability and asymmetry. Some pedicles were not suitable for atlantoaxial transarticular screw fixation. The risks associated with screw fixation should be prevented by preoperative computed tomography with three-dimensional reconstruction. Screw trajectory reconstruction with coronal and sagittal reconstruction is useful to evaluate the pedicle width and height.

Atlanto-Axial Joint↗