Faculty Bibliography

BACKGROUND/UNASSIGNED:Our hypothesis was that lumbar adhesive arachnoiditis (AA)/chronic lumbar AA (CAA) are clinical diagnoses that do not require radiographic confirmation. Therefore, patients with these syndromes do not necessarily have to demonstrate significant radiographic abnormalities on myelograms, MyeloCT studies, and/or MR examinations. When present, typical AA/CAA findings may include; central or peripheral nerve root/cauda equina thickening/clumping (i.e. latter empty sac sign), arachnoid cysts, soft tissue masses in the subarachnoid space, and/or failure of nerve roots to migrate ventrally on prone MR/Myelo-CT studies. METHODS/UNASSIGNED:We reviewed 3 articles and 7 clinical series that involved a total of 253 patients with AA/CAA to determine whether there was a significant correlation between these clinical syndromes, and myelographic, Myelo-CT, and/or MR imaging pathology. RESULTS/UNASSIGNED:We determined that patients with the clinical diagnoses of AA/CAA do not necessarily exhibit associated radiographic abnormalities. However, a subset of patients with AA/CAA may show the classical AA/CAA findings of; central or peripheral nerve root/cauda equina thickening/clumping (empty sac sign), arachnoid cysts, soft tissue masses in the subarachnoid space, and/or failure of nerve roots to migrate ventrally on prone MR/ Myelo-CT studies. CONCLUSION/UNASSIGNED:Patients with clinical diagnoses of AA/CAA do not necessary show associated neuroradiagnostic abnormalities on myelograms, Myelo-CT studies, or MR. Rather, the clinical syndromes of AA/CAA may exist alone without the requirement for radiolographic confirmation.

Background/UNASSIGNED:Traumatic injury to the spine can be a complex diagnostic and therapeutic entity often with devastating consequences. Outside of the isolated vertebral column injury costs; annual costs associated with spinal cord injury (SCI) are estimated to exceed $9.7 billion. Objective/UNASSIGNED:To identify the 100 most-cited articles on spine trauma. Methods/UNASSIGNED:The Thomson Reuters Web of Science citation indexing service was queried. The articles were sorted by times cited in descending order. Two independent reviewers reviewed the article titles and abstracts to identify the top 100 most-cited articles. Results/UNASSIGNED:The top 100 articles were found to be cited between 108 (articles #99-100) and 1595 times (article #1). The most-cited basic science article was cited 340 times (#12 on the top 100 list). The oldest article on the top 100 list was from 1953 and most recent from 2012. The number of patients, when applicable, in a study ranged from 9 (article #34) to 34,069 (article #5). Top 100 articles were published in 41 different journals with a wide range of specialities and fields most commonly multidisciplinary. Basic science research encompassed 34 of the 100 articles on the list. Conclusions/UNASSIGNED:We present the 100 most-cited articles in spinal trauma with emphases on important contributions from both basic science and clinical research across a wide range of authors, specialties, patient populations, and countries. Recognizing some of the most important contributions in the field of spinal trauma may provide insight and guide future work.

Background/UNASSIGNED:A traumatically shattered lumbosacral junction/pelvis may be difficult to repair. Here the authors offer a pelvic fixation technique utilizing routine pedicle screws, interbody lumbar fusions, bilateral iliac screws/ rods/crosslinks, and bilateral fibular strut allografts from the lumbar spine to the sacrum. Methods/UNASSIGNED:A middle aged male sustained a multiple storey fall resulting in a left sacral fracture, and right sacroiliac joint (SI) dislocation. The patient had previously undergone attempted decompressions with routine pedicle screw L4-S1 fusions at outside institutions; these failed twice. When the patient was finally seen, he exhibited, on CT reconstructed images, MR, and X-rays, a left sacral fracture nonunion, and a right sacroiliac joint dislocation. Results/UNASSIGNED:The patient underwent a bilateral pelvic reconstruction utilizing right L4, L5, S1 and left L4, L5 pedicle screws plus interbody fusions (L4-L5, and L5, S1), performed from the left. Unique to this fusion construct was the placement of bilateral double iliac screws plus the application of bilateral fibula allografts from L4-sacrum filled with bone morphogenetic protein (BMP). After rod/screw/connectors were applied, bone graft was placed over the fusion construct, including the decorticated edges of the left sacral fractures, and right SI joint dislocation. We additionally reviewed other pelvic fusion reconstruction methods. Conclusions/UNASSIGNED:Here, we utilized a unique pelvic reconstruction technique utilizing pedicle screws/rods, double iliac screws/rods, and bilateral fibula strut grafts extending from the L4-sacrum filled with BMP.

Background/UNASSIGNED:Spine surgeons encounter occasional complex cerebrospinal fluid fistulas/dural tears (CSF/DT) during lumbar spinal surgery. In some cases, these leaks are found during the index procedure, but others may appear postoperatively, or in the course of successive procedures. Here we asked, whether these complex CSF fistulas/DT could be more readily repaired utilizing a "bone suture anchor" technique, particularly where there is no residual dural margin/remnant. Methods/UNASSIGNED:With the combined expertise of the orthopedist and neurosurgeon, mini/micro bone suture anchors, largely developed for hand surgery, facilitated repair of complex DT occurring during lumbar spine surgery. This technique was utilized to suture in place fascia, periosteal, or muscle grafts, and was followed by the application of microfibrillar collagen, and a fibrin sealant. Results/UNASSIGNED:This mini/micro suture anchor technique has now been utilized to repair multiple significant intraoperative and/or postoperative recurrent DT, largely avoiding the need to place lumbar drains and/or lumbo- peritoneal shunts. Conclusions/UNASSIGNED:Here, we reviewed how to directly suture dural grafts utilizing a mini/micro bone suture anchor technique to repair complex intraoperative primary/recurrent DT occurring during lumbar spine surgery. The major advantages of this technique, in addition to obtaining definitive occlusion of the DT, largely avoids the need to place lumbar drains and/or lumbo-peritoneal shunts with their attendant risks and complications.

Reconstruction of bony defects in the surgical management of vertebral osteomyelitis is a challenging endeavor. Our objective is to report the use of intra-abdominal vessels as the recipient vessels for microanastomosis of vascularized bone graft and the use of a spinal cage for fixation. Three patients failed conservative treatment for vertebral osteomyelitis and suffered pathologic fracture. Their treatment consisted of staged posterior irrigation and debridement with segmental fixation, followed by a thoracoabdominal approach multiple-level corpectomy. Reconstruction was performed with a free vascularized fibular graft placed within a custom, expandable cage. The vascularized fibular graft was anastomosed to an intra-abdominal recipient vessel. All patients improved clinically with no neurologic deficits noted. All showed evidence of successful fusion. Free vascularized bone grafts continue to be an excellent option for multi-level spinal defects related to osteomyelitis. Intra-abdominal recipient vessels are appropriate recipient vessels, as their diameter, length, and accessibility allow vascularized bone graft reconstruction of vertebral column defects of the thoracolumbar region. These vessels are also easily accessible and the anastomoses can be performed in the superficial operating incision.

STUDY DESIGN/METHODS:Clinical case series. OBJECTIVE:To show the efficacy of prophylactic inferior vena cava (IVC) filters in preventing venous thromboembolic event (VTE) in high-risk patients undergoing major spinal surgery. SUMMARY OF BACKGROUND DATA/BACKGROUND:Patients undergoing major spinal surgery are at increased risk for VTEs. Recent studies have shown IVC filters are effective in preventing clinically significant pulmonary embolism (PE), but have not documented the frequency of all emboli prevented. METHODS:Patients undergoing major spinal surgery from 2006 to 2009, having IVC filters placed for VTE prophylaxis, were reviewed. Patients with 2 or more risk factors for VTE were included and their perioperative courses were reviewed for PE and device-related complications. Cavograms obtained at the time of attempted filter retrieval identified intercepted emboli. The rates of intercepted emboli and clinical PEs were compared with those of similar populations undergoing similar procedures. RESULTS:Approximately 17% of patients had entrapped thrombus present at attempted filter retrieval. An additional 17% of filters were unable to be retrieved due to change in position within the IVC. No patients experienced symptomatic PE. One patient developed a deep vein thrombus requiring pharmacologic treatment and another patient developed superficial phlebitis. There were no complications related to IVC filter use. CONCLUSIONS:These findings show that the decreased rate of PE observed in this and other series is likely because of the use of IVC filters, rather than sampling bias inherent when studying a relatively rare problem. The safety of IVC filters in this population is also confirmed. The observed rate of clinical PE is consistent with other published series. Emboli intercepted by filters may more accurately estimate clinically significant emboli prevented. Therefore, cavograms may prove to be a valuable method of assessing the efficacy of these devices in future studies.

BACKGROUND CONTEXT/BACKGROUND:Cervical flexion teardrop fractures (CFTF) are highly unstable injuries, and the optimal internal fixation construct is not always clearly indicated. PURPOSE/OBJECTIVE:The purpose of the current study was to determine whether the type of fixation construct (anterior, posterior, or combined) or number of joint levels involved in fixation (one or two) affected the relative stability of a CFTF injury at C5-C6. STUDY DESIGN/SETTING/METHODS:Human cadaveric cervical spine specimens were mechanically tested under displacement control in the intact state and after creation of CFTF at C5-C6 with stabilization using five different instrumentation constructs. Joint stiffness and intervertebral translation of the constructs were compared with the intact state and normalized (instrumented/intact) to assess relative differences across the five constructs. METHODS:Spine specimens were mechanically tested in the intact state during flexion, extension, lateral bending, and axial rotation. CFTF was created at C5-C6 by creating an osteotomy at C5 and transecting the posterior ligaments and intervertebral disc. Specimens were tested with anterior, posterior, and combined single-level constructs (C5-C6). Then, a corpectomy was performed at C5, and specimens were retested with the two-level constructs (C4-C6; anterior and anterior-posterior). Joint stiffness and intervertebral translations were computed. RESULTS:All five fixation constructs resulted in joint stability that was as good as or better than that of the intact specimens. Relative stiffness of the constructs differed depending upon the motion type considered, though the two-level anterior-posterior construct typically provided the greatest stability. Intervertebral translation along the major axis was reduced the most for both of the combined instrumentation systems, although there were few changes in total intervertebral translation across the five constructs. CONCLUSIONS:All five constructs restored stability comparable to that of the intact specimens. The significance of the relative differences in constructs for the in vivo spine is unclear and warrants further clinical investigation.