Short Review/Perspective on Adjacent Segment Disease (ASD) Following Cervical Fusion Versus Arthroplasty
Background/UNASSIGNED:Although the incidence of radiographic Adjacent Segment Disease (ASD) following anterior cervical diskectomy/fusion (ACDF) or cervical disc arthroplasty (CDA) typically ranges from 2-4%/year, reportedly fewer patients are symptomatic, and even fewer require secondary surgery. Methods/UNASSIGNED:Multiple studies have documented a 2-4% incidence of radiographic ASD following either ACDF or CDA per year. However, fewer are symptomatic from ASD, and even fewer require additional surgery/reoperations. Results/UNASSIGNED:In a meta-analysis (2016) involving 83 papers, the incidence of radiographic ASD per year was 2.79%, but symptomatic disease was present in just 1.43% of patients with only 0.24% requiring secondary surgery. In another study (2019) involving 38,149 patients undergoing ACDF, 2.9% (1092 patients; 0.62% per year) had radiographic ASD within an average of 4.66 postoperative years; the younger the patient at the index surgery, the higher the reoperation rate (i.e. < 40 years of age 4.56 X reoperations vs. <70 at 2.1 X reoperations). In a meta-analysis of 32 articles focusing on ASD 12-24 months following CDA, adjacent segment degeneration (ASDeg) occurred in 5.15% of patients, but adjacent segment disease (AS Dis) was noted in just 0.2%/ year. Further, AS degeneration occurred in 7.4% of patients after 1-level vs. 15.6% following 2 level fusions, confirming that CDA's "motion-sparing" design did not produce the "anticipated" beneficial results. Conclusion/UNASSIGNED:The incidence of radiographic ASD ranges from 2-4% per year for ACDF and CDA. Additionally, both demonstrate lesser frequencies of symptomatic ASD, and the need for secondary surgery. Further, doubling the frequency of ASD following 2 vs. 1-level CDA, should prompt surgeons to limit surgery to only essential levels.
The 100 Most-Cited Papers in Traumatic Injury of the Spine
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.
Reconstruction of Shattered Lumbo-Sacral Junction/Pelvis Utilizing Bilateral L4-Sacrum Fibula Strut Allograft And Double Iliac Screws Plus Routine Lumbar Pedicle Screw Fixation
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.
Unique Bone Suture Anchor Repair of Complex Lumbar Cerebrospinal Fluid Fistulas
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.
Spinal reconstruction for osteomyelitis with free vascularized fibular grafts using intra-abdominal recipient vessels: A series of three cases
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.
Prophylactic inferior vena cava filters prevent pulmonary embolisms in high-risk patients undergoing major spinal surgery
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.
Biomechanical evaluation of surgical constructs for stabilization of cervical teardrop fractures
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.