Internal architecture of the talus: implication for talar fracture.

The internal architecture of the talus has not previously been well described even though the morphological anatomy and the blood supply have been studied extensively. This study describes the internal architecture of the talus regarding its trabecular orientation, using high-resolution x-ray images of 13 dry tali and thick sections in the coronal, sagittal, and axial planes. The trabecular arrays and their relationship to talar fractures are described.

Computed tomographic evaluation of the internal structure of the lateral sacral mass in the upper sacra.

Because dimensions of the upper sacral cortexes vary greatly among individuals, preoperative computed tomographic (CT) evaluation of individual sacrum may help surgeons choose sacral screw insertion techniques. Axial CT scans were performed on 40 dry sacrum specimens to quantitatively evaluate the internal structure of the lateral sacral mass in the first and second segments. The results showed that the greatest cortical thickness in the S1 vertebra was found in the anterior cortex (3.

The vertebral artery: surgical anatomy.

Anterior cervical decompressive surgery is widely performed for spondylosis, herniated intervertebral disk, tumor, infection, and trauma in the subaxial cervical spine region. Laceration of the vertebral artery is the most challenging of surgical dilemmas during anterior cervical spine surgery, as gaining control of the massive hemorrhage from a ruptured vertebral artery is difficult and could possibly result in an uncertain neurologic morbidity. As such, the understanding the surgical anatomy of the vertebral artery is essential to prevent iatrogenic injuries.

Evaluation of the upper sacrum by three-dimensional computed tomography.

Axial and sagittal computed tomographic (CT) scans of 40 sacrum specimens were obtained. The measurements of the upper sacral canal and S1-2 and S2-3 anterior sacral foramina were performed on axial scans, and the evaluation of the upper sacral pedicle was based on sagittal scans. The results showed that there were statistically significant differences between male and female specimens in 3 of 29 measurements.

The quantitative study of the lateral region to the lumbar pedicle.

Background: An anatomic study of the lumbar nerve lateral to the pedicle was performed on 12 cadavers. Three courses of the lumbar nerve were noted around the pedicle. The direct measurements, including the angle of the lumbar rami with the spinal cord, the axis of the pedicle with the cord in the coronal plane, and the distance between the lateral border of the pedicle to the rami, were made bilaterally.

Anatomic bases for anterior spinal surgery: surgical anatomy of the cervical vertebral body and disc space.

Twenty adult cadaveric cervical spines were sectioned longitudinally through the midline to display longitudinal sections of the vertebral bodies and disc spaces from C3 to T1. Computer-assisted anatomic images were obtained for measurements of the disc spaces and vertebral bodies. Anteroposterior (AP) depth gradually increased from 16.

Anatomic considerations for anterior instrumentation of the lumbar spine.

One hundred seventy lumbar vertebrae from L1-L4 were used to quantitatively evaluate the lumbar vertebral body and examine the relationship of the maximum posterior angles of screw placement to the spinal canal. Anatomic evaluation included dimensions of the vertebral body. Three entrance points on the lateral aspect of the vertebral body for screw insertion and an additional point 3 mm from the posterolateral corner of the spinal canal were defined and marked.

The anatomic relation of lateral mass screws to the spinal nerves. A comparison of the Magerl, Anderson, and An techniques.

Study Design: Analysis of the anatomic relation of the Magerl, Anderson, and An screws to the spinal nerve.

Objectives: To compare the potential incidence of nerve root (ventral and dorsal ramus) injury caused by the Magerl, Anderson, and An techniques.

Summary Of Background Data: Posterior plating with lateral mass screw fixation is a common procedure for managing an unstable cervical spine.

CT-guided sacroiliac joint injections.

Confusion surrounding low back pain syndrome may partially be resolved in a select small group of patients by instituting a provocative intraarticular injection of a combination of a local anesthetic and a steroid. This approach enables one to determine whether the sacroiliac joint (SIJ) is the site of origin of the low back pain syndrome. We carried out a study of 71 computed tomography (CT)-guided injections in 58 patients with noninflammatory etiology.

Subtalar arthroscopy for persistent subfibular pain after calcaneal fractures.

This is a report of 10 consecutive patients who had subtalar arthroscopy for persistent pain in the subfibular area after open reduction and internal fixation for intra-articular calcaneal fractures. The average period between the injury and the subtalar arthroscopy was 14.3 months (range, 6-36 months).

External rotation-lateral view of the ankle in the assessment of the posterior malleolus.

Demonstration of a posterior malleolar fragment on a radiograph of an ankle fracture is important in the diagnosis and evaluation of posterior malleolus fractures. The size and extent of displacement of a posterior malleolar fragment can be evaluated. The diagnosis of non-union of the posterior malleolus is also important because it can lead to failure of reduction of ankle fractures.

Thoracic pedicle screw placement guided by computed tomographic measurements.

Cadaveric pedicle screw placement guided by the measurements from axial computed tomography (CT) scans in the thoracic spine was assessed in this study. Axial CT scans were performed on four cadaveric thoracic spines, and the measurements included the pedicle transverse angle, inner pedicle width, and distance between the midline of the vertebra and the pedicle axis on the dorsal aspect of the lamina. With utilization of the data from CT scans, screws were directly placed into the thoracic pedicle from T1 to T10.

Are anatomic landmarks reliable in determination of fusion level in posterolateral lumbar fusion?

Study Design: Determination of the fusion level by direct observation and palpation of anatomic landmarks is compared with the finding obtained from a lateral intraoperative radiograph.

Objectives: To assess the reliability of the use of intraoperative anatomic landmarks in determination of the fusion level.

Summary Of Background Data: Accurate determination of the level to be fused in noninstrumented posterolateral fusion is crucial.

Extensile approach to the anterolateral surface of the humerus and the radial nerve.

A proposed approach to the anterolateral surface of the humeral shaft that would allow for exploration of the radial nerve was studied in 30 cadaver arms. The incision starts proximally along the posterior border of the deltoid muscle and extends anteriorly and distally over the lateral border of the biceps muscle. A deep dissection is made in the internervous plane between the deltoid and the triceps muscles proximally and between the longitudinally split fibers of the brachialis muscle distally.

The projection of the cervical disc and uncinate process on the posterior aspect of the cervical spine.

Background: Surgical techniques of foraminotomy for decompression of the cervical nerve have been well described in the literature. Excessive resection of the facet joint and laminae may decrease segmental stability and increase scar formation. How much bony resection is adequate to remove a soft or hard disc herniation is not known.

Radiographic evaluation of the calcaneocuboid joint: a cadaver study.

Eighteen cadaver feet were used for radiographic evaluation of the calcaneocuboid joint. The articular surface of the cuboid on all specimens was painted with a radiopaque material. Fractures and 1-mm step-off of the fractures were simulated in six specimens.

Magnetic resonance imaging evaluation of thecal sac diameters following laminectomy in the lumbar spine.

Sagittal magnetic resonance images (MRIs) from 20 patients who had postoperative persistent or recurrent low back pain were reviewed to study the thecal sac diameter at laminectomy sites. The thecal sac anteroposterior diameter was measured in three sites: the maximum AP diameter at the laminectomy site, and the proximal and distal levels to the laminectomy site. A comparison between the thecal sac AP diameter at laminectomy sites and the average diameter of both the proximal and distal levels was then made.

Anatomic relation between the cervical pedicle and the adjacent neural structures.

Study Design: An evaluation of the anatomic relation between the cervical pedicles and the adjacent neural structures.

Objectives: To determine quantitatively the antomic relation of the cervical pedicles to the adjacent nerve roots and dural sac.

Summary Of Background Data: Transpedicular screw fixation in the cervical spine has been reported, but little quantitative data regarding the anatomic relation between the cervical pedicles and the surrounding neural structures are known.

Cartilage and synovium of the peroneocuboid joint: an anatomic and histological study.

The surface area, thickness, and composition of the articular cartilage of the peroneocuboid articulation and the location of the synovium were investigated in 15 cadaver foot specimens. The articulations of the medial side of the peroneus longus tendon and lateral side of the cuboid were covered with fibrous and hyaline cartilages, respectively. On the lateral tuberosity of the cuboid, there is a facet that has 79.

Anatomic relationship of the cervical nerves to the lateral masses.

Eight cervical specimens were transversely sectioned with slices approximately 2 mm to 3 mm in thickness to evaluate the anatomic relationship of the spinal nerves to the lateral masses. Results showed that the spinal nerve either does not appear or, when it does, is situated anteromedially to the superior facet on the cross sections through the upper portion of the superior facet. The anterolateral aspect of the superior facet is free from the spinal nerve.

Anatomic basis of the anterior surgery on the cervical spine: relationships between uncus-artery-root complex and vertebral artery injury.

Vertebral artery injury is a serious complication during anterior surgery on the cervical spine. However, little information is available in the literature concerning the mechanism of vertebral artery laceration during the procedures of the anterior cervical decompression. In the current study twenty-eight cadavers were dissected to determine the location and relationships of the fibro-ligamentous tissues to the uncinate process, vertebral artery and nerve roots from the C3 to C6 levels.

The quantitative anatomy of the laminas of the spine.

Study Design: This study evaluated the dimensions of the laminas from C2 to L5 using adult spine specimens.

Objectives: To provide a set of quantitative data for the laminas from C2 to L5.

Summary Of Background Data: Anatomic evaluation of the pedicle and facet joint in the spine has been extensively reported.

Open reduction and internal fixation of fracture of the posterior process of the talus: a case report and review of the literature.

A fracture of the posterior process of the talus is rare. In this report, we present a case of isolated displaced fracture of the posterior process of the talus, which was treated by early open reduction and internal fixation through a posteromedial approach. The fracture healed without evidence of avascular necrosis of either the posterior fragment or the talar body.

Radiographic evaluation of talonavicular joint after talar screw placement: a cadaver study.

Twelve cadaver feet were used for a radiographic assessment of the talonavicular joint. A 4.0- or a 6.

Quantitative anatomy of the transverse foramen and pedicle of the axis.

Forty dry C2 cervical vertebrae were obtained to evaluate quantitatively the anatomy of the C2 transverse foramen and pedicle. Computed tomography (CT) scans and plain radiographs were also obtained of 20 specimens to evaluate the internal structure of the transverse foramen and pedicle. The results of the measurements showed that differences between male and female specimens were found to be significant for four of seven linear parameters and for one of the two angular parameters.