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Background: Despite the extensive use of cellular bone matrices (CBMs) in spine surgery, there is little evidence to support the contribution of cells within CBMs to bone formation. The objective of this study was to determine the contribution of cells to spinal fusion by direct comparisons among viable CBMs, devitalized CBMs, and cell-free demineralized bone matrix (DBM).Methods: Three commercially available grafts were tested: a CBM containing particulate DBM (CBM-particulate), a CBM containing DBM fibers (CBM-fiber), and a cell-free product with DBM fibers only (DBM-fiber). CBMs were used in viable states (CBM-particulatev and CBM-fiberv) and devitalized (lyophilized) states (CBM-particulated and CBM-fiberd), resulting in 5 groups. Viable cell counts and bone morphogenetic protein-2 (BMP-2) content on enzyme-linked immunosorbent assay (ELISA) within each graft material were measured. A single-level posterolateral lumbar fusion was performed on 45 athymic rats with 3 lots of each product implanted into 9 animals per group. After 6 weeks, fusion was assessed using manual palpation, micro-computed tomography (μ-CT), and histological analysis.Results: The 2 groups with viable cells were comparable with respect to cell counts, and pairwise comparisons showed no significant differences in BMP-2 content across the 5 groups. Manual palpation demonstrated fusion rates of 9 of 9 in the DBM-fiber specimens, 9 of 9 in the CBM-fiberd specimens, 8 of 9 in the CBM-fiberv specimens, and 0 of 9 in both CBM-particulate groups. The μ-CT maturity grade was significantly higher in the DBM-fiber group (2.78 ± 0.55) compared with the other groups (p < 0.0001), while none of the CBM-particulate samples demonstrated intertransverse fusion in qualitative assessments. The viable and devitalized samples in each CBM group were comparable with regard to fusion rates, bone volume fraction, μ-CT maturity grade, and histological features.Conclusions: The cellular component of 2 commercially available CBMs yielded no additional benefits in terms of spinal fusion. Meanwhile, the groups with a fiber-based DBM demonstrated significantly higher fusion outcomes compared with the CBM groups with particulate DBM, indicating that the DBM component is probably the key determinant of fusion.Clinical Relevance: Data from the current study demonstrate that cells yielded no additional benefit in spinal fusion and emphasize the need for well-designed clinical studies on cellular graft materials. [ABSTRACT FROM AUTHOR]

Background: As concerns regarding health-care expenditure in the U.S. remain at the national forefront, outpatient arthroplasty is an appealing option for carefully selected patient populations. The purpose of this study was to determine the nationwide trends and complication rates associated with outpatient total knee arthroplasty (TKA) in comparison with standard inpatient TKA.Methods: We performed a retrospective review of the Humana subset of the PearlDiver Patient Record Database to identify patients who had undergone TKA (Current Procedural Terminology [CPT] code 27447) as either outpatients or inpatients from 2007 to 2015. The incidence of perioperative medical and surgical complications was determined by querying for relevant International Classification of Diseases, Ninth Revision (ICD-9) and CPT codes. Multivariate logistic regression analysis adjusted for age, sex, and Charlson Comorbidity Index (CCI) was used to calculate odds ratios (ORs) of complications among outpatients relative to inpatients treated with TKA.Results: Cohorts of 4,391 patients who underwent outpatient TKA and 128,951 patients who underwent inpatient TKA were identified. The median age was in the 70 to 74-year age group in both cohorts. The incidence of outpatient TKA increased across the study period (R = 0.60, p = 0.015). After adjustment for age, sex, and CCI, outpatient TKAs were found to more likely be followed by tibial and/or femoral component revision due to a noninfectious cause (OR = 1.22, 95% confidence interval [CI] = 1.01 to 1.47; p = 0.039), explantation of the prosthesis (OR = 1.35, CI = 1.07 to 1.72; p = 0.013), irrigation and debridement (OR = 1.50, CI = 1.28 to 1.77; p < 0.001), and stiffness requiring manipulation under anesthesia (OR = 1.28, CI = 1.17 to 1.40; p < 0.001) within 1 year. Outpatient TKA was also more frequently associated with postoperative deep vein thrombosis (OR = 1.42, CI = 1.25 to 1.63; p < 0.001) and acute renal failure (OR = 1.13, CI = 1.01 to 1.25; p = 0.026).Conclusions: With the potential to minimize arthroplasty costs among healthy patients, outpatient TKA is an increasingly popular option. Nationwide data from a private insurance database demonstrated a higher risk of perioperative surgical and medical complications including component failure, surgical site infection, knee stiffness, and deep vein thrombosis.Level Of Evidence: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence. [ABSTRACT FROM AUTHOR]

The article discusses the treatment use in cervical spine abnormalities. Topics discussed include the use of tubular retractor and endoscopic camera, and microscope in posterior cervical microendoscopic decompression, the use of radiographic fusion to compare flexion and measure the interspinous process tip distance with extension radiographs, and the use of computed tomography (CT).

The article offers information in spine surgery updates. Topics discussed include the report on cervical myelopathy which shows that 20% of 60% of patients who have cervical myelopathy had myelopathy had subsequent neurologic deterioration if the condition was not treated surgically, data on spinal cord deformity surgery, and the efficacy of nonoperative management in treating lumbar spine.

Background: Previous studies have suggested that the co-expression of two different bone morphogenetic protein (BMP) genes can result in the production of heterodimeric BMPs that may be more potent than homodimers. In this study, combined BMP-2 and BMP-7 gene transfer was performed ex vivo to compare the resulting new bone formation with that of single-BMP gene transfer in a rat spinal fusion model. Methods: Forty-four athymic rats underwent posterolateral fusion at L4-L5 and were implanted with a collagen sponge containing human adipose-derived stem cells. Group A received untreated cells, and the remaining groups received cells transfected with various genes in a lentivirus vector. The transferred genes were GFP (green fluorescent protein) in Group B, BMP-2 in Group C, BMP-7 in Group' D, and both BMP-2 and BMP-7 in Group E. In vitro production of BMP-2 and BMP-7 was quantified by means of an enzyme-linked immunosorbent assay (ELISA) specific to BMP-2 or BMP-7. Osseous fusion was quantified with use of radiography and microcomputed tomography. Results: ELISA demonstrated that Group E, which was treated with both BMP-2 and BMP-7, produced less than one-fourth as much BMP as the groups treated with a single transfected BMP (Groups C and D). Radiographs showed that all of the spines in Groups C, D, and E appeared to be fused by eight weeks; the spines in Groups A and B showed minimal evidence of new bone formation. Measurements confirmed that the mean bone formation area was significantly greater in Groups C, D, and E compared with Groups A and B (p < 0.001). In addition, the bone formation area was significantly greater in Group E compared with Groups C and D (p < 0.001). Conclusions: Combined BMP-2 and BMP-7 ex vivo gene transfer was found to be significantly more effective for inducing new bone formation compared with ex vivo gene transfer of an individual BMP in a rat spinal fusion model. Clinical Relevance: Combined BMP-2 and BMP-7 therapy may lead to efficient bone regeneration. [ABSTRACT FROM AUTHOR]

The article offers information related to spine surgery. It mentions that laminoplasty and anterior decompression and arthrodesis are the two common surgical approaches for the treatment of cervical spondylotic myelopathy. It notes that the Surgical Treatment of Acute Spinal Cord Injury Study (ASCIS) which compares change in American Spinal Injury Association (ASIA) Impairment Scale was completed.

The article discusses the new approaches in the field of spinal surgery. It includes the developments in various aspects including cervical spine treatment, treatment of the lumbar spine and spinal cord injury. Information on the diagnostic evaluation, treatment methodology and complications is presented. It also includes the meetings and events related to spinal surgery that will be held in nearby future.

The article discusses the recent developments in cervical spine treatment as of 2011. It mentions a study of cervical myelopathy which showed a significant result following the determination of differences of anterior and posterior cervical spine surgery. It cites disc arthroplasty which continuously demonstrated a good outcome as cervical spine therapy. It also notes atlantoaxial arthrodesis which is proven to be an efficient treatment for patients with nonrheumatoid destructive arthropathy.

Background: Growth factors like bone morphogenetic protein (BMP) are used as bone-graft substitutes to enhance bone growth in clinical situations. However, adverse reactions have been associated with BMP use. We developed a synthetic adjuvant therapy based on the sequence of a BMP-binding protein, secreted phosphoprotein-24 (spp24), which enhances the effects of BMP5 and ameliorates the adverse reactions. Our hypothesis is that a natural proteolytic fragment of spp24 is identical to an osteogenic protein previously described independently by two investigators. To test this hypothesis, spp24 and a truncated form of spp24 were separately implanted with recombinant human BMP-2 (rhBMP-2) in a rodent model of spine fusion. Methods: Two isoforms of spp24 were constructed with use of DNA recombinant technology. Spp24 with or without rhBMP-2 were added to collagen sponges and implanted bilaterally between L4 and L5 transverse processes Radio- graphs were made biweekly, and spines were explanted after eight weeks. Gross evaluation, microquantitative computed tomography study, and histological analysis were performed to evaluate bone growth. Results: Animals that received full-length spp24 and rhBMP-2 exhibited a complete obliteration of bone growth, while animals with the truncated form in combination with rhBMP-2 exhibited a mild inhibition to bone growth, with bone area measured from radiographs. Manual assessment and gross evaluation of all spines confirmed the results obtained from the bone-area measurements. Microquantitative computed tomography provided three-dimensional visual images of representative specimens, while histological staining of spine tissue displayed cellular evidence of bone formation. Conclusions: Results from this investigation confirm that the various isoforms of spp24 affect the bone-healing activity of rhBMP-2 in the rat spine fusion model. Thus, proteolytic modification of this protein is a likely mechanism for the regulation of BMP availability in the physiological environment. Future studies will define the roles of these proteins in controlling the activity of BMP5 and other members of the transforming growth factor-beta family of cytokines. This information will increase the understanding of normal bone-healing, allowing for the engineering of more effective orthopaedic treatment. [ABSTRACT FROM AUTHOR]

The article offers updates related to spine surgery in the U.S. It states the comparison between anterior and posterior treatment of thoracolumbar and lumbar adolescent idiopathic scoliosis. It notes several upcoming meetings including the Forty-fifth Annual Meeting of the Scoliosis Research Society (SRS) from September 21 to 24, 2010 in Kyoto, Japan. It adds the timing of surgical intervention and the use of developed pharmaceutical agents to minimize injury or to promote nerve regeneration.

The article focuses on the value of spine surgery as relative to the symposium presented at the Annual Meeting of the American Orthopaedic Association on June 10-13, 2009 in Bonita Springs, Florida. It states that the patients with degenerative spondylolisthesis that was treated surgically showed improvement related to pain and functions. It says that the patients with lumbar degenerative spinal stenosis showed a significant improvement in all primary outcomes after the surgical procedure.

Background: Demineralized bone matrix is an osteoinductive allograft derived from processed bone that is commonly mixed with autogenous bone in fusion procedures to treat diseases of the spine. An increasing number of demineralized bone matrix-based products are commercially available for spinal fusion procedures, but osteoinductive variability has been found not only across different products but also among production lots from the same demineralized bone matrix formulation. The purpose of this study was to assess the lot-to-lot variability across a single demineralized bone matrix-based product in terms of both extracted bone morphogenetic protein (BMP) concentrations (in vitro) and fusion performance in rats (in vivo). The goal was also to determine whether the in vitro measures could sufficiently and accurately predict the in vivo fusion performance of different demineralized bone matrix-based product lots. Methods: BMP-2 and BMP-7 were extracted from ten production lots of InterGro DBM Putty and quantified with use of ELISA (enzyme-linked immunosorbent assay). A posterolateral lumbar spinal fusion was performed on forty athymic rats with implantation of a demineralized bone matrix-based product. Fusion success was determined at eight weeks with use of radiographs and manual palpation of the segments. Logistic regression was used to determine the predictive abilities of BMPs. Results: Significant lot-to-lot variability was found in terms of both BMP concentrations (22 to 110 μg of BMP-2 per milligram of product and 44 to 125 μg of BMP-7 per milligram of product) and in vivo rates of fusion (0% to 75%; p < 0.04 for all). BMP-2 and BMP-7 concentrations correlated positively with each other across lots (r = 0.77, p < 0.0001). Most notably, extracted amounts of BMP-2 and BMP-7 each predicted in a dose-dependent manner the in vivo fusion performance in rats (R2 = 0.32, p < 0.01 for BMP-2, and R2 = 0.22, p < 0.009 for BMP-7). Conclusions: Assays for demineralized bone matrix-extracted BMP-2 and BMP-7 levels may be feasible and sufficient for predicting spinal fusion performance of individual production lots from the same demineralized bone matrix-based product. [ABSTRACT FROM AUTHOR]

The article highlights recent developments to the surgical treatment of spine diseases. It cited different updates to the surgical treatment of cervical spine pathology, spinal deformity surgery, surgery for spinal cord injury and surgical treatment for lumbar spine disorders. It also describes new developments in biologics related to the spine.

The article presents an overview of trends which are being seen in 2008 in the surgical treatment of the cervical spine, which include the evaluation of new technology and a renewed focus on the understanding of old treatment concepts and postulates. A discussion of research which has been done on the effectiveness of cervical arthroplasty is presented.

Background: Mesenchymal stem cells derived from human liposuction aspirates, termed processed lipoaspirate cells, have been utilized as cellular delivery vehicles for the induction of bone formation in tissue engineering and gene therapy strategies. In this study, we sought to evaluate the efficacy of bone morphogenetic protein (BMP)-2-producing adipose- derived stem cells in inducing a posterolateral spine fusion in an athymic rat model. Methods: Single-level (L4-L5) intertransverse spinal arthrodesis was attempted with use of a type-I collagen matrix in five groups of athymic rats, with eight animals in each group. Group I was treated with 5 × 106 adipose-derived stem cells transduced with an adenoviral vector containing the BMP-2 gene; group II, with 5 × 106 adipose-derived stem cells treated with osteogenic media and 1 μg/mL of recombinant BMP-2 (rhBMP-2); group Ill, with 10 μg of rhBMP-2; group IV, with 1 μg of rhBMP-2; and group V, with 5 × 106 adipose-derived stem cells alone. The animals that showed radiographic evidence of healing were killed four weeks after cell implantation and were examined with plain radiographs, manual palpation, microcomputed tomography scanning, and histological analysis. Results: All eight animals in group I demonstrated successful spinal fusion, with a large fusion mass, four weeks postoperatively. Furthermore, group-I specimens consistently revealed spinal fusion at the cephalad level (L3 and L4), where no fusion bed had been prepared surgically. In contrast, despite substantial BMP-2 production measured in vitro, group-II animals demonstrated minimal bone formation even eight weeks after implantation. Of the groups treated with the application of rhBMP-2 alone, the one that received a relatively high dose (group III) had a higher rate of fusion (seen in all eight specimens) than the one that received the low dose (group IV, in which fusion was seen in four of the eight specimens). None of the group-V animals (treated with adipose-derived stem cells alone) demonstrated successful spine fusion eight weeks after the surgery. Conclusions: Adipose-derived stem cells show promise as gene transduction targets for inducing bone formation to enhance spinal fusion in biologically stringent environments. Clinical Relevance: Adipose-derived stem cells demonstrate potential as cellular vehicles for the delivery of recombinant protein in a regional gene therapy strategy to enhance spinal fusion. However, before the exclusive use of adipose-derived stem cells in a cell-based strategy can become routine, more extensive study of the biological potential, the interactions between different carriers, and the influence of host biology is necessary. [ABSTRACT FROM AUTHOR]

The article offers developments in the treatment of the cervical spine. Disc arthroplasty is currently undergoing rigorous clinical testing, and the outcomes of this procedure are being compared with those of fusion in randomized controlled trials. Expansive laminoplasty for decompression in patients with multilevel spinal cord stenosis and myelopathy generally has been discussed.

Provides information on advancements in spine surgery. Popularity of laminoplasty for the treatment of cervical myelopathy secondary to ossification of the posterior longitudinal ligament and spondylosis with spinal stenosis; Continued effort to enhance the process of achieving spine fusion; Developments in spinal deformity surgery; Discovery of novel approaches in the treatment of the lumbar spine.

Background: A primary concern after posterior lumbar spine arthrodesis is the potential for adjacent segment degeneration cephalad or caudad to the fusion segment. There is controversy regarding the subsequent degeneration of adjacent segments, and we are aware of no long-term studies that have analyzed both cephalad and caudad degeneration following posterior arthrodesis. A retrospective investigation was performed to determine the rates of degeneration and survival of the motion segments adjacent to the site of a posterior lumbar fusion. Methods: Two hundred and fifteen patients who had undergone posterior lumbar arthrodesis were included in this study. The study group included 126 female patients and eighty-nine male patients. The average duration of follow-up was 6.7 years. Radiographs were analyzed with regard to arthritic degeneration at the adjacent levels both preoperatively and at the time of the last follow-up visit. Disc spaces were graded on a 4-point arthritic degeneration scale. Correlation analysis was used to determine the contribution of independent variables to the rate of degeneration. Survivorship analysis was performed to describe the degeneration of the adjacent motion segments. Results: Fifty-nine (27.4%) of the 215 patients had evidence of degeneration at the adjacent levels and elected to have an additional decompression (fifteen patients) or arthrodesis (forty-four patients). Kaplan-Meier analysis predicted a disease-free survival rate of 83.5% (95% confidence interval, 77.5% to 89.5%) at five years and of 63.9% (95% confidence interval, 54.0% to 73.8%) at ten years after the index operation. Although there was a trend toward progression of the arthritic grade at the adjacent disc levels, there was no significant correlation, with the numbers available, between the preoperative arthritic grade and the need for additional surgery. Conclusions: The rate of symptomatic degeneration at an adjacent segment warranting either decompression or arthrodesis was predicted to be 16.5% at five years and 36.1% at ten years. There appeared to be no correlation with the length of fusion or the preoperative arthritic degeneration of the adjacent segment. Level of Evidence: Prognostic study, Level IV (case series). See Instructions to Authors for a complete description of levels of evidence. [ABSTRACT FROM AUTHOR]

Background: Bone morphogenetic proteins (BMPs) are now being used as bone-graft substitutes to enhance spinal fusion. However, the large doses of BMP required to induce a spinal fusion in humans suggests that the delivery of these proteins should be improved. We used ex vivo adenoviral gene transfer to create BMP-2-producing bone marrow cells, and these autologous cells were found to induce a posterolateral fusion of the spine in syngeneic rats.Methods: Intertransverse spinal arthrodesis (L4 and L5) was attempted in ten groups of Lewis rats with 5 x 10 (6) BMP-2-producing rat bone marrow cells (Ad-BMP-2 cells), created through adenoviral gene transfer with guanidine hydrochloride-extracted demineralized bone matrix as a carrier (Group I); 5 x 10 (6) Ad-BMP-2 cells on a collagen sponge carrier (Group II); 10 micro g of recombinant BMP-2 (rhBMP-2) in a guanidine hydrochloride-extracted demineralized bone matrix carrier (Group III); 10 micro g of rhBMP-2 in a collagen sponge carrier (Group IV); autogenous iliac crest bone-grafting (Group V); 5 x 10 (6) beta-galactosidase-producing rat bone marrow cells, created through adenoviral gene transfer with guanidine hydrochloride-extracted demineralized bone matrix as a carrier (Group VI); decortication of the transverse processes alone (Group VII); 5 x 10 (6) uninfected rat bone marrow cells with a guanidine hydrochloride-extracted demineralized bone matrix carrier (Group VIII); guanidine hydrochloride-extracted demineralized bone matrix only (Group IX); or a collagen sponge alone (Group X). Each specimen underwent plain radiography, manual palpation, and histological analysis.Results: All spines in Groups I and II (BMP-2-producing bone marrow cells) and all spines in Groups III and IV were fused at four weeks postoperatively. In contrast, none of the spines in the other groups had fused at a minimum of eight weeks after implantation. Histological analysis of the specimens revealed that the spines that had received BMP-2-producing bone marrow cells (Groups I and II) were filled with coarse trabecular bone postoperatively, whereas those that had received rhBMP-2 (Groups III and IV) were filled with thin, lace-like trabecular bone. All of the other spines, including those that had been treated with autogenous iliac crest bone-grafting (Group V), produced little or no new bone.Conclusion: BMP-2-producing bone marrow cells, created by adenoviral gene transfer, produce sufficient BMP to induce an intertransverse fusion in the rat spine model. [ABSTRACT FROM AUTHOR]

Background: The radiographic anatomy of the cervical spine in children is complex and can be difficult to interpret. The present study was undertaken to document radiographically the growth and development of the cervical spine in a prospective, longitudinal manner and to establish standard radiographic measurements on the basis of findings in patients who were followed serially from the age of three months until skeletal maturity. Methods: The radiographic resources of the Cleveland Study of Normal Growth and Development (Bolton-Brush Collection, Cleveland, Ohio) were reviewed. From this large database, we identified fifty boys and forty-six girls who had a sufficient number of radiographs of the cervical spine for inclusion in our study. With use of a computerized image analyzer, the growth and development of the atlantodens interval, the diameter of the spinal canal, the Torg ratio, the height and width of the second through fifth cervical vertebral bodies, the height of the dens, and the ossification of the first cervical vertebra were assessed on serial radiographs made from the age of three months until skeletal maturity. Results: Serial measurements of the atlantodens interval, the anteroposterior diameter of the cervical canal, the height and anteroposterior width of the cervical vertebral bodies, and the height of the dens, made in normal, healthy children from the age of three months to fifteen years, are presented in tabular and graphic forms. The median Torg ratio was 1.47 for both males and females primarily, and it reached values of 1.06 for males and 1.10 for females by maturity. The anterior arch of the first cervical vertebra had ossified in 33% of the children by the age of three months and in 81% of the children by the age of one year. Closure of the synchondroses was completed in all children by the age of three years. Conclusions: The measurements presented in the current study are important because they are the first, as far as we know, to... [ABSTRACT FROM AUTHOR]