Pasquale X. Montesano

1988 Volvo award in clinical sciences. Facet joint injection in low-back pain. A prospective statistical study.

From January 1980 through December 1984, 454 patients were evaluated with facet joint injections. All had the chief complaint of low-back pain, normal neurologic examinations and no root tension signs. Three hundred and ninety completed the protocol, which included a lumbar motion pain assessment before and after facet injection. A total of 127 variables were studied. There were 229 males and 161 females with a median age of 38. Facet joint arthrograms were performed prior to intra-articular injection of local anesthetic and cortisone. Initial mean pain relief was only 29%. Variables correlating significantly (P < 0.05) with more postinjection pain relief were older age, prior history of low-back pain, normal gait, maximum pain on extension following forward flexion in the standing position, and the absence of leg pain, muscle spasm and aggravation of pain on Valsalva. Greatest pain relief immediately after injection was seen with lumbar extension and rotation, motions reported to stress the facet joints or aggravate pain of facet joint origin. Patients with more pain on lumbar extension and rotation as a group, however, did not get more pain relief. From this study we were not able to identify clinical facet joint syndromes or predict patients responding better to this procedure. The facet joints were not commonly the single or primary source for low-back pain in the great majority (>90%) of patients studied.

Biomechanics of cervical spine internal fixation.

Recent advances in the area of cervical spine internal fixation have resulted in important additions to the armamentarium of the spine surgery. However, a sophisticated knowledge of the biomechanics of these devices is important. This article discusses the biomechanics of odontoid screws, anterior cervical plates, posterior cervical plates, and posterior C1—C2 screw arthrodesis. It is hoped that this information will aid in implant selection.

Odontoid fractures treated by anterior odontoid screw fixation.

While odontoid fractures are common injuries, disagreement exists regarding treatment. Some authors claim a high rate of pseudoarthrosis and have therefore recommended early posterior fixation and fusion. This, however, results in decreased cervical rotation. Therefore, it has been recommended that a more direct approach to the fracture be taken. Results on anterior screw fixation in 14 patients are reported. The technique was found to be especially useful in multiple trauma patients, patients who refuse halo treatment, and in some nonunions.

Enhancement of lumbar spine fusion by use of translaminar facet joint screws.

From January 1983 to March 1986 the authors have performed 88 consecutive lumbosacral spine fusion, enhanced with translaminar facet screws, as described by F. Magerl of St. Gallen, Switzerland. Forty-three patients have a follow-up of 12 months or greater, for a mean follow-up time of 16 months. The median time to fusion in this group was 6 months, with a range of 6 weeks to 10 months. Ninety-three percent of the patients were found to be clinically improved, and 91% of patients were judged solidly fused on evaluation of motion radiographs. Compared with our previously reported results for lumbar fusion without internal fixation, supplementation of lumbar fusion by translaminar facet screw fixation significantly improved the clinical results, as well as the time required for fusion, with no significant increased risk.

Management of thoracolumbar fractures with accompanying neurological injury.

The optimal surgical approach for spinal canal reconstruction of thoracolumbar fractures is controversial, and the relationship between spinal canal reconstruction and neurological recovery remains unclear. To address these issues, 22 consecutive cases of thoracolumbar fracture with accompanying neurological deficit were reviewed. Neurological status was graded at the time of admission, postoperatively, and at a mean of 15 months postinjury. By using preoperative and postoperative radiographs and computed tomographic scans, the degree of spinal canal compromise was quantified in the sagittal, coronal, and axial planes. All fractures were stabilized by posterior instrumentation and fusion, and in 10 injuries, retropulsed vertebral body fragments were further reduced by posterolateral decompression. Spinal canal dimensions, neurological function, and operative approach were compared by using nonparametric statistical analysis. The greater the initial spinal canal compromise, the more severe the neurological deficit (P = 0.04). With injuries involving L1 and above, this relationship increased (P = 0.003). The extent of spinal canal reconstruction failed to correlate with neurological recovery. Compared with spinal instrumentation alone, transpedicular decompression showed no benefit in terms of postoperative canal dimensions or neurological outcome. On the basis of this experience, transpedicular decompression offers no advantage over spinal instrumentation alone. The relationship between initial spinal canal encroachment and neurological deficit demonstrates that the degrees of bony and neurological injury directly reflect the kinetic energy transferred at the time of impact. The lack of correlation between the extent of spinal canal reconstruction and neurological recovery suggests that ongoing neural compression/distortion contributes little to the overall neurological injury.

Is there a role for diskography in the era of magnetic resonance imaging? Prospective correlation and quantitative analysis of computed tomography-diskography, magnetic resonance imaging, and surgical findings

We herein report the results of a prospective study to define the role of diskography in the diagnosis of low back pain in an emerging era of magnetic resonance imaging (MRI). The study involved 32 patients (78 disks) with a clinical diagnosis of lumbar disk herniation; all were studied by computed tomography-diskography (CT-D), and 25 (51 disks) were also examined using MRI. The disks were graded on these studies according to a staging scheme modified from Modic. Ten of the patients (13 disks) having both CT-D and MRI underwent exploratory surgery, and the staging at surgery served as the standard against which the evaluative studies were judged. Surgical staging was compatible with the CT-D and MRI results in five disks, while in another five disks it was compatible only with the CT-D results. In the remaining three disks, both CT-D and MRI misidentified the stages. In six disks, CT-D more accurately defined the stage of disease than did MRI, whereas MRI was more precise than CT-D in only one disk. While having documented the value of CT-D as a source of information, particularly when surgery is contemplated, and as an effective means of staging disk herniation, we recommend MRI as the ideal screening test for lumbar radiculopathy and low back pain, reserving diskography for problematic cases.

Treatment of kyphotic deformity in ankylosing spondylitis.

This article reviews the available literature on the surgical options for the correction of kyphosis in ankylosing spondylitis and presents the radiologic appearance of the post-operative spine. In the postsurgical evaluation of the spine, the focus is on appreciation of the patterns of correction, early and late determination of angular correction, recognition of various complications (infection, nonunion, improper location, or breakage of hardware), and alertness to the possibility of complications at all levels of the spine.

Screw Fixation of the Odontoid Process

Summary: Screw fixation of odontoid fractures is a technically demanding procedure. However, in the hands of a fellowship trained spine surgeon, it is an important augmentation technique in the care of spinal injuries.

Neural Monitoring During Orthopaedic Spine Surgery: Rationale and Case Studies

Using a basic technique and modifying it as needed lends reliability and validity in the intraoperative assessment of spinal cord function. As a major trauma and spine center, we have monitored 390 cases with intraoperative somatosensory-evoked potentials over the past 59 months.