No abstract available.
Laminectomy

Approaching to high lumbar level, the width of laminar decrease and conventional laminectomy for the management of L1-2 or L2-3 disc herniation may cause fracture of inferior articular facets of L1 or L2 vertebrae. We performed anterolateral approach to preserve posterior elements(destruction of which may cause later spinal instability), for the management of high lumbar disc herniation.
Laminectomy ; Spine

The surgical approach to spinal tumors varies not only with the level and location of the tumor, but also with the type and extent of the tumor. Some of the dumbbell neurofibroma(neurilemmoma) can be removed through simple laminectomy, but usually are approached through two separate incisions by two stages. In this report, posterior and anterolateral approaches in a single stage to dumbbell neurofibroma(neurilemmoma) of the spinal region are described. This approach provides full exposure of intra- and paraspinal portions of the tumor, thus permitting safe dissection and total removal. Six patients who underwent this procedure are described to illustrate its application.
Humans ; Laminectomy ; Neurofibroma ; Spine*

No abstract available.
Arteriovenous Fistula* ; Laminectomy*

C1/2 posterior transarticular screw fixation has become an accepted method of rigid internal fixation for patients requiring posterior C1/2 fusion. Especially,Surgery for Os odontoideum can be troublesome due to its severe tranlational instability, canal stenosis requiring decompressive laminectomy and defective C1 posterior arch. The author reports three cases of complicated Os odontoideum(one case of failed occipito-C2 fusion, two cases requiring C1 laminectomy) with C1/2 transarticular screw fixation and interarticular bone fusion. All required decompressive laminectomy and demonstrated highly unstable translational instabilities. On the basis of these experiences, it is postulated that C1/2 transarticular screw fixation seems to be superior to other methods in stabilization and fusion for complicated Os-odontoideum.
Constriction, Pathologic ; Humans ; Laminectomy

STUDY DESIGN: An experimental biomechanical study. PURPOSE: This study aims to investigate the behavior of a lamina injury in lumbar burst fractures during reduction maneuvers. OVERVIEW OF LITERATURE: Lumbar burst fractures are frequently accompanied by a lamina fracture. Many researchers concluded that any reduction maneuver will close the fractured lamina edges and possibly crush the entrapped neural elements. This conclusion did not rely on solid biomechanical trials and was based primarily on clinical experience. METHODS: Eighteen fresh-frozen lamb spines were randomly divided into three groups. Using the preinjury and the dropped-mass technique, a burst fracture model was developed. A central laminectomy of 5 mm of the L3 lumbar spine was created to mimic a complete type of lamina fracture. To measure the movement of the fractured laminar edges, two holes were drilled on both sides of the upper and lower regions of the lamina to allow for optic marker placement. A single specific spine movement was applied to each group: traction, flexion, and extension. Gap changes were measured by camera extensometers. RESULTS: After traction, the average values of the upper and lower aspects of the lamina interval showed narrowing of 1.65±0.82 mm and 1.97±1.14 mm, respectively. No statistical significance was detected between the two aspects. The upper and lower regions of the lamina gap behaved differently during extension. At 10°, 20°, and 30°, the upper part of the lamina interval was widened by an average of 0.016±0.024, 0.29±0.32, and 1.73±1.45 mm, respectively, whereas the lower part was narrowed by an average of 0.023±0.012, 0.47±0.038, and 1.94±1.46 mm, respectively. CONCLUSIONS: Neural element crushing may take place, particularly at the lower aspect of the fractured lamina gap during extension and throughout the whole lamina gap during traction. The lamina gap widens during flexion. Reduction maneuvers should be attempted after exploring the fractured lamina to prevent further neurological compromise.
Laminectomy ; Spine ; Traction

No abstract available.
Constriction, Pathologic* ; Decompression* ; Laminectomy*

No abstract available.
Cicatrix* ; Diskectomy* ; Laminectomy* ; Rabbits*

PURPOSE: To determine the utility of the nutrient foramen on the lamina in thoracic pedicle screw fixation. MATERIALS AND METHODS: This study investigated the nutrient foramina on the lamina from 4th to 8th thoracic vertebra after partial laminectomy of 7 cadaveric spines. A 2 mm steinmann pin was inserted as follows: Vertical insertion on the right nutrient foramen and a 10 degree caudad on the left nutrient foramen. Radiographs and CT were obtained and the relationships between steinmann pin and pedicle were analyzed. RESULTS: There were 44 nutrient foramens (63%). Among them, 31 nutrient foramens (70%, 31/44) were on the right. On the lateral radiograph, the right pins were inserted to the upper end plate and the left pins were inserted within the vertebral body in T4 and T5. In T6, 7 and 8, the right pins were inserted lower than the upper end plate, and the left pins were inserted to the lower portion of the vertebral body. On the CT axial scan, medialization to 17 degrees from T4 to T7 and 5 degrees in T8 from the nutrient foramen was possible when the size of pedicle screw for humans is considered. CONCLUSION: The nutrient foramens on the lamina of thoracic vertebra are useful for inserting the thoracic pedicle screw.
Cadaver ; Humans ; Laminectomy ; Spine

No abstract available.
Animals ; Cats* ; Laminectomy* ; Spine*