Evaluating the Academic Influence of Orthopedic Surgeons in Spinal Literature Through Relative Citation Ratio.

INTRODUCTION:  The innovative iCite tool applies the relative citation ratio (RCR) to gauge the time and field-adjusted scientific influence of a publication. This study examines scholarly effects on spine surgery to distinguish the impact made by orthopedic surgeons, neurosurgeons, and several other specialists. MATERIALS AND METHODS:  From 2013 to 2017, 100 of the highest RCR-rated articles were gathered for each of the following terms: cervical disc herniation (CDH), lumbar disc herniation (LDH), lumbar spinal stenosis (LSS), neurogenic claudication (NC), radiculopathy (RAD), and sciatica (SC). The first, second, and last authors were queried for background and academic qualifications and placed into the following specialty categories: orthopedic surgery, neurosurgery, pain management, medicine, and others. To provide an alternative degree of influence, the Scopus database was employed to classify the h-index associated with each author. RESULTS:  Across the six search terms, there were 526 orthopedic surgeons among 1,730 authors (30.4%), with the highest representation in LSS (118/290, 40.7%), and the lowest in SC (45/286, 15.7%). Orthopedics was the most influential specialty across all six research terms by median RCR (p = 0.012). Compared to their neurosurgical counterparts, orthopedic authors had a greater influence in CDH (3.93 vs. 2.63, p = 0.0492), LDH (5.10 vs. 4.99, p = 1.0000), NC (2.16 vs. 1.40, p = 0.2370), and SC (3.35 vs. 3.04, p = 0.5285), but had a lower influence in LSS (5.13 vs. 5.32, p = 0.7736) and RAD (5.03 vs. 6.05, p = 0.3938). CONCLUSION:  Orthopedic surgeons lead other specialties when determining scholarly influence through RCR across six of the pre-designated research domains within spine surgery. For orthopedics, a modest influence in LSS and RAD may suggest potential areas of future focus. The use of bibliometrics to analyze available literature enables us to identify other specialties that have contributed to our field and promote interdisciplinary collaboration.

Patient Satisfaction with Orthopedic Telemedicine Health Visits During the COVID-19 Pandemic.

Background:Telemedicine usage in orthopedic surgery has seen a dramatic increase as a result of the severe acute respiratory syndrome coronavirus 2 pandemic. The purpose of this study was to examine patient perceptions with telemedicine at a large orthopedic practice.Materials and Methods:An anonymous online survey was distributed to all patients who received a telemedicine health visit at our institution for musculoskeletal complaints from March 17 to June 1, 2020. Responses were scored on a 5-point Likert scale (strongly disagree, disagree, neutral, agree, and strongly agree, 1-5) and analyzed by average score and percent reaching top box.Results:A majority of patients (76.5%) were satisfied with their visit, and only 19.2% did not want telemedicine as a future option. Patients who presented for follow-up visits (4.11 vs. 3.94, p = 0.0053; 48% vs. 41%, p = 0.02) and utilized video (4.21 vs. 3.88, p < 0.001; 51% vs. 39%, p < 0.001) were more satisfied. Average satisfaction between older (>65 years) and younger patients was similar (4.06 vs. 4.06, p = 0.97), however, younger patients were more likely to reach top box (42% vs. 51%, p < 0.001). Confidence that the physician came to the correct diagnosis (r = 0.78, p < 0.001) and receiving the same information and care as an in-office visit (r = 0.60, p < 0.001) demonstrated the strongest correlation with satisfaction and desire for future telemedicine visits, respectively. Interestingly, 31.1% of patients would have sought treatment elsewhere had telemedicine not been an option.Conclusions:Overall, satisfaction rates are high for orthopedic patients undergoing telemedicine visits. Patients are more confident in telemedicine when presenting for a follow-up visit and with the use of video.

Differences in Patient and Physician Perceptions of Urgency for Musculoskeletal Conditions During the COVID-19 Pandemic.

In 2020, the coronavirus disease 2019 (COVID-19) pandemic limited musculoskeletal care to urgent or "nonelective" office visits and procedures. No guidelines exist to inform patients or physicians what meets these criteria. The purpose of this multi-institutional study was to describe the differences in perceptions of urgency for musculoskeletal complaints between patients and providers during the COVID-19 pandemic. An anonymous survey was distributed to patients who visited the authors' orthopedic clinics in January and February 2020 and practicing orthopedic surgeons. The surveys were administered in May 2020 after COVID-19 was officially labeled a pandemic and included questions regarding demographic information and perceptions of orthopedic urgency. A total of 1491 patients and 128 physicians completed the surveys. A significantly higher percentage of physicians considered the following diagnoses an appropriate indication for an urgent visit compared with patients: fracture (P<.001), acute dislocation (P<.001), infection (P<.001), neurologic compromise (P<.001), tumor (P<.001), acute tendon injury (P<.001), weakness (P<.001), inability to bear weight (P<.001), post-surgical problem (P<.001), and painful joint effusion (P<.001). There were no significant differences in the perception of urgency for the following conditions: bursitis/tendonitis (P=1.00), joint/extremity deformity without pain (P=.113), and loss of range of motion of a joint (P=.467). Younger patients and those with higher levels of education were significantly more likely to consider their conditions urgent. Patients may require additional education to prevent delay in treatment of urgent conditions-especially time-sensitive conditions such as neurologic compromise, tumors, and infections-when access to physicians is limited. [Orthopedics. 2021;44(4):e534-e538.].

Correlation of Early Outcomes and Intradiscal Interleukin-6 Expression in Lumbar Fusion Patients.

OBJECTIVE: To determine if there is correlation between intradiscal levels of interleukin-6 (IL-6) and early outcome measures in patients undergoing lumbar fusion for painful disc degeneration. METHODS: Intervertebral disc tissue was separated into annulus fibrosus/nucleus pulposus and cultured separately in vitro in serum-free medium (Opti-MEM). Conditioned media was collected after 48 hours. The concentration of IL-6 was quantified using enzyme-linked immunosorbent assay. Pearson correlation coefficients quantified relationships between IL-6 levels and pre- and postoperative visual analogue scale (VAS) back pain and Oswestry Disability Index (ODI), as well as change in VAS/ODI. RESULTS: Sixteen discs were harvested from 9 patients undergoing anterior lumbar interbody fusion (mean age, 47.4 years; range, 21-70 years). Mean preoperative and 6-month postoperative VAS were 8.1 and 3.7, respectively. Mean preoperative and postoperative ODI were 56.2 and 25.6, respectively. There were significant positive correlations between IL-6 expression and postoperative VAS (ρ = 0.38, p = 0.048) and ODI (ρ = 0.44, p = 0.02). No significant correlations were found between intradiscal IL-6 expression and preoperative VAS (ρ = -0.12, p = 0.54). Trends were seen associating IL-6 expression and change in VAS/ODI (ρ = -0.35 p = 0.067; ρ = -0.34, p = 0.08, respectively). A trend associated IL-6 and preoperative ODI (ρ = 0.36, p = 0.063). CONCLUSION: The direct association between IL-6 expression and VAS/ODI suggests patients with elevated intradiscal cytokine expression may have worse early outcomes than those with lower expression of IL-6 after surgery for symptomatic disc degeneration.

Does Riluzole Influence Bone Formation?: An In Vitro Study of Human Mesenchymal Stromal Cells and Osteoblast.

STUDY DESIGN: A post-test design biological experiment. OBJECTIVE: The aim of this study was to evaluate the osteogenic effects of riluzole on human mesenchymal stromal cells and osteoblasts. SUMMARY OF BACKGROUND DATA: Riluzole may benefit patients with spinal cord injury (SCI) from a neurologic perspective, but little is known about riluzole's effect on bone formation, fracture healing, or osteogenesis. METHODS: Human mesenchymal stromal cells (hMSCs) and human osteoblasts (hOB) were obtained and isolated from healthy donors and cultured. The cells were treated with riluzole of different concentrations (50, 150, 450 ng/mL) for 1, 2, 3, and 4 weeks. Cytotoxicity was evaluated as was the induction of osteogenic differentiation of hMSCs. Differentiation was evaluated by measuring alkaline phosphatase (ALP) activity and with Alizarin red staining. Osteogenic gene expression of type I collagen (Col1), ALP, osteocalcin (Ocn), Runx2, Sox9, Runx2/Sox9 ratio were measured by qRT-PCR. RESULTS: No cytotoxicity or increased proliferation was observed in bone marrow derived hMSCs and primary hOBs cultured with riluzole over 7 days. ALP activity was slightly increased in hMSCs after treatment for 2 weeks with riluzole 150 ng/mL and slightly upregulated by 150% (150 ng/mL) and 90% (450 ng/mL) in hMSCs at 3 weeks. In hOBs, ALP activity almost doubled after 2 weeks of culture with riluzole 150 ng/mL (P < 0.05). More pronounced 2.6-fold upregulation was noticed after 3 weeks of culture with riluzole at both 150 ng/mL (P = 0.05) and 450 ng/mL (P = 0.05). No significant influence of riluzole on the mRNA expression of osteocalcin (OCN) was observed. CONCLUSION: The effect of riluzole on bone formation is mixed; low-dose riluzole has no effect on the viability or function of either hMSCs or hOBs. The activity of ALP in both cell types is upregulated by high-dose riluzole, which may indicate that high-dose riluzole can increase osteogenic metabolism and subsequently accelerate bone healing process. However, at high concentrations, riluzole leads to a decrease in osteogenic gene expression, including Runx2 and type 1 collagen. LEVEL OF EVIDENCE: N/A.

The local cytokine and growth factor response to recombinant human bone morphogenetic protein-2 (rhBMP-2) after spinal fusion.

BACKGROUND CONTEXT: The systemic response regarding cytokine expression after the application of recombinant human bone morphogenetic protein-2 (rhBMP-2) in a rat spinal fusion model has recently been defined, but the local response has not been defined. Defining the local cytokine and growth factor response at the fusion site will help explain the roles of these molecules in the fusion process, as well as that of rhBMP-2. Our hypothesis is that the application of rhBMP-2 to the fusion site will alter the local levels of cytokines and growth factors throughout the fusion process, in a manner that is different from the systemic response, given the tissue-specific effects of rhBMP-2. PURPOSE: The purpose of this study was to evaluate the local cytokine and growth factor response after the application of rhBMP-2 in a rat spinal fusion model. STUDY DESIGN/SETTING: This was a basic science animal model study. METHODS: This study was partially funded by a physician-sponsored grant from Medtronic. A total of 135 Wistar rats (age 8 weeks, weighing approximately 300-400 g) underwent L4-L5 posterolateral intertransverse fusion with demineralized bone graft (approximately 0.4-cm3 rat demineralized bone matrix [DBM] per side). In the first group, 10 µg of rhBMP-2 on an allograft collagen sponge (ACS) was added to the fusion site with approximately 0.4-cm3 rat DBM per side. In the second group, 100 µg of rhBMP-2 on an ACS was added to the fusion site with approximately 0.4-cm3 rat DBM per side, and the third experiment was the control group, which consisted of only an ACS plus 0.4-cm3 DBM per side. There were nine groups of five animals each per experiment. Each group was sacrificed at time points up to 4 weeks (1, 6, 24, and 48 hours, and 4, 7, 14, 21, and 28 days after surgery). At sacrifice, the DBM, transverse processes, and any new bone formed were harvested, immediately frozen in liquid nitrogen, and prepared for protein extraction. ELISA was performed to compare the levels of various cytokines (interleukin [IL]-1ß, tumor necrosis factor alpha, IL-6, IL-1RA [IL-1 receptor antagonist], IL-4, and IL-10) and growth factors (vascular endothelial growth factor [VEGF], endothelia growth factor [EGF], insulin-like growth factor-1 [IGF-1], platelet derived growth factor [PDGF], transforming growth factor beta [TGF-ß]) that are known to be involved in the fusion-fracture healing process. Fusion was evaluated on the rats sacrificed at 28 days by manual palpation and microcomputed tomography (microCT) by two independent observers. RESULTS: The expression of cytokines and growth factors varied throughout the fusion process at each time point. In the groups treated with rh-BMP-2, IL-6 and IL-1RA had higher expression in the early time points (1 and 6 hours). Tumor necrosis factor alpha demonstrated significantly lower expression in the groups treated with rhBMP-2 at Days 1, 2, and 4. At the early time points (1 and 6 hours), in the groups treated with rhBMP-2, all of the growth factors IGF-1, VEGF, platelet derived growth factor AB (PDGF-AB), TGF-ß had equal or lower expression compared with controls. At 24 hours, there was a peak in IGF-1, VEGF, and PDGF-AB. These growth factors then declined, with IGF-1 and PDGF-AB having a second peak at Day 7. At 4 weeks, all of the rhBMP-2-treated animals fused based on manual palpation and microCT. The control group had four of five rats fused based on manual palpation and two of five rats based on microCT. CONCLUSIONS: There is significant variability in the expression of cytokines throughout the fusion process after treatment with rhBMP-2. The inflammatory response appears to peak early (1 and 6 hours), followed by a significant decrease with rhBMP-2 treatment. However, the growth factor expression appears to be suppressed early (1 and 6 hours), followed by a peak at 24 hours, and a second peak at Day 7.

Outcome of a Resident Spine Surgical Skills Training Program.

STUDY DESIGN: Cadaver training lab. OBJECTIVE: To determine if a technical cadaver skills training lab for spinal surgery increases resident confidence, satisfaction in training, and perception of operating room safety. SUMMARY OF BACKGROUND DATA: Resident training is an important topic in the setting of work hour reform. The use of supplemental materials such as videos, sawbones, and simulators may become important to adequately train orthopedic residents. At present, there are no established curricula for training orthopedic surgery residents on anatomy and common procedures encountered during a spinal surgery rotation. METHODS: Residents were assembled into teams of a PGY-5 and PGY-2 and/or PGY-1 to perform dissection and procedures on 5 fresh-frozen spine cadavers. With attending and spine fellow supervision, residents performed anterior cervical, posterior cervical, and posterior thoracolumbar surgical exposure, decompression, and fusion procedures in the operating room using surgical tools and instrumentation. Residents were then queried about their confidence levels, satisfaction in training, and perception of safety using a Likert scale (0-10). Strong agreement (scores ≥8) and strong disagreement (scores ≤3) and correlations were evaluated. RESULTS: Seventeen residents completed the training program (7 PGY-1s, 2 PGY-2s, and 8 PGY-5s). After the training, the majority of residents strongly agreed that they had an increased confidence of their own abilities (59%). A significant majority (65%) of residents strongly agreed that they were satisfied with the benefits provided by the training program. Compared with other methods of education, residents strongly agreed that the training was more helpful than textbook chapters (94%), sawbones (94%), web-based training (94%), or a virtual-based (completely electronic) training (94%). After the training, residents strongly agreed that the training improved feelings of preparation (47%), safety (41%), and ability to prevent intraoperative errors (41%). The vast majority of residents strongly agreed "Before performing surgery on me, I would want a resident to perform this cadaveric training" (88%). CONCLUSIONS: These results demonstrate that team-based, cadaveric training with adequate attending supervision, before onset of a spine surgical rotation, may lead to high resident confidence, satisfaction in training, and perception of patient safety.

Are Modic changes associated with intervertebral disc cytokine profiles?

BACKGROUND CONTEXT: Degenerative changes including Modic changes (MCs) are commonly observed in patients with chronic low back pain. Although intervertebral disc (IVD) cytokine expression has been shown to be associated with low back pain, the cytokine profile for degenerative IVD with and without MC has not been compared. PURPOSE: This study aimed to evaluate the potential association between IVD cytokine expression and MCs. STUDY DESIGN: A laboratory study was carried out. METHODS: The IVD tissue samples from 10 patients with type II MCs and10 patients without MCs who underwent an anterior lumbar interbody and fusion for significant low back pain were collected. The expression levels of 42 cytokines were determined using a RayBio Human Cytokine Antibody Array 3 (RayBiotech Inc, Norcross, GA, USA) and the results were verified with enzyme-linked immunosorbent assay (ELISA). RESULTS: The cytokine array demonstrated a statistically significant increase in the expression of granulocyte-macrophage colony-stimulating factor (GM-CSF) (p=.001) and epithelial-derived neutrophil-activating peptide 78 (ENA-78) (p=.04), and a trend toward an increase in interleukin-1ß (IL-1ß) (p=.12) and tumor necrosis factor-α (TNF-α) (p=.22) in IVDs associated with type II MCs. These results were validated with ELISA which demonstrated a 3.85-fold increase in the GM-CSF level between IVDs with type II MCs compared with those without MCs (p=.03). Similarly there was a significant increase in the level of both ENA-78 (3.68-fold, p=.02) and IL-1ß (2.11-fold, p=.01) in IVDs with type II MCs. Lastly, there was a trend (p=.07) toward an increase in TNF-α in IVDs with type II MCs (4.4-fold). CONCLUSION: Intervertebral discs with type II MCs demonstrate a significant increase in IL-1ß, GM-CSF, and ENA-78, and there is a trend toward an increase in TNF-α. These results further strengthen the association between MCs and low back pain.

The surgical algorithm for the AOSpine thoracolumbar spine injury classification system.

PURPOSE: The goal of the current study is to establish a surgical algorithm to accompany the AOSpine thoracolumbar spine injury classification system. METHODS: A survey was sent to AOSpine members from the six AO regions of the world, and surgeons were asked if a patient should undergo an initial trial of conservative management or if surgical management was warranted. The survey consisted of controversial injury patterns. Using the results of the survey, a surgical algorithm was developed. RESULTS: The AOSpine Trauma Knowledge forum defined that the injuries in which less than 30% of surgeons would recommend surgical intervention should undergo a trial of non-operative care, and injuries in which 70% of surgeons would recommend surgery should undergo surgical intervention. Using these thresholds, it was determined that injuries with a thoracolumbar AOSpine injury score (TL AOSIS) of three or less should undergo a trial of conservative treatment, and injuries with a TL AOSIS of more than five should undergo surgical intervention. Operative or non-operative treatment is acceptable for injuries with a TL AOSIS of four or five. CONCLUSION: The current algorithm uses a meaningful injury classification and worldwide surgeon input to determine the initial treatment recommendation for thoracolumbar injuries. This allows for a globally accepted surgical algorithm for the treatment of thoracolumbar trauma.

A Survey On Spine Surgeons' Opinions On The Release Of The Centers for Medicare and Medicaid Services Data.

BACKGROUND: In April 2014 the Centers for Medicare and Medicaid Services (CMS) released a dataset for the public which included information on services provided by physicians and healthcare providers for Medicare beneficiaries in the 2012 calendar year. The objective of this study is to determine spine surgeons' opinions on the release of the CMS data, and determine how they feel this information may affect patient care. METHODS: A survey was sent to members of the Association for Collaborative Spine Research (ACSR) regarding their practice patterns and opinions on the release of the CMS data. Determinants included surgical subspecialty, practice setting, years in practice and region. The average response was collected for each question and compared across groups. Additionally, questions in which greater than 75% of respondents either agreed (agree or strongly agree) or disagreed (disagree or strongly disagree) were identified. RESULTS: Seventy-six surgeons completed the survey, and while the overall interobserver reliability between each question was only slight (κ = 0.11), more than 75% of respondents either agreed or strongly agreed with five statements and, more than 75% of respondents either disagreed or strongly disagreed with six statements. While 86% of surgeons are in favor of more transparency, 83% of respondents felt that without the proper context, the data released does not accurately portray spine surgery. Additionally, 96% of spine surgeons do not believe the CMS data helps patients decide which spine surgeon is best for them. CONCLUSIONS: The small percentage of spine surgeons who responded to this survey are in favor of more transparency but do not feel the release of the CMS data either accurately represents spine surgeons or will help patients better identify the appropriate surgeon. In spite of these concerns, it is unlikely the release of the CMS data will significantly impact the accessibility of a spine surgeon to a Medicare beneficiary.

Can a Thoracolumbar Injury Severity Score Be Uniformly Applied from T1 to L5 or Are Modifications Necessary?

Study Design Literature review. Objective The aim of this review is to highlight challenges in the development of a comprehensive surgical algorithm to accompany the AOSpine Thoracolumbar Spine Injury Classification System. Methods A narrative review of the relevant spine trauma literature was undertaken with input from the multidisciplinary AOSpine International Trauma Knowledge Forum. Results The transitional areas of the spine, in particular the cervicothoracic junction, pose unique challenges. The upper thoracic vertebrae have a transitional anatomy with elements similar to the subaxial cervical spine. When treating these fractures, the surgeon must be aware of the instability due to the junctional location of these fractures. Additionally, although the narrow spinal canal makes neurologic injuries common, the small pedicles and the inability to perform an anterior exposure make decompression surgery challenging. Similarly, low lumbar fractures and fractures at the lumbosacral junction cannot always be treated in the same manner as fractures in the more cephalad thoracolumbar spine. Although the unique biomechanical environment of the low lumbar spine makes a progressive kyphotic deformity less likely because of the substantial lordosis normally present in the low lumbar spine, even a fracture leading to a neutral alignment may dramatically alter the patient's sagittal balance. Conclusion Although the new AOSpine Thoracolumbar Spine Injury Classification System was designed to be a comprehensive thoracolumbar classification, fractures at the cervicothoracic junction and the lumbosacral junction have properties unique to these junctional locations. The specific characteristics of injuries in these regions may alter the most appropriate treatment, and so surgeons must use clinical judgment to determine the optimal treatment of these complex fractures.

Substance P Receptor Antagonist Suppresses Inflammatory Cytokine Expression in Human Disc Cells.

STUDY DESIGN: Laboratory study. OBJECTIVE: To evaluate whether blockade of the Substance P (SP) NK1R attenuates its proinflammatory effect on human intervertebral disc cells (IVD), and to evaluate the signaling pathways associated with SP. SUMMARY OF BACKGROUND DATA: SP and its receptors are expressed in human IVD cells, and cause upregulation of inflammatory mediators; however, the effects of blocking these receptors have not been studied in human IVD cells. METHODS: Human annulus fibrosus (AF) and nucleus pulposus (NP) cells were expanded in monolayer, and then suspended in alginate beads. The alginate beads were treated with culture medium first containing a high affinity NK1R antagonist (L-760735) at different concentrations, and then with medium containing both NK1R antagonist and SP at 2 concentrations. Ribonucleic acid was isolated and transcribed into cDNA. Quantitative reverse transcriptase-polymerase chain reaction (RT-PCR) was performed to evaluate expression of interleukin (IL)-1ß, IL-6, and IL-8. Western blot analysis was performed to examine levels of the phosphorylated p38 mitogen-activated protein kinase (MAPK), extracellular signal regulated kinase 1/2 (ERK1/2) and nuclear factor kappa-light-chain-enhancer of activated B cells (NFκB p65). The cells were pretreated with specific inhibitors of p38 (SB203580), ERK1/2 (PD98059), and p65 (SM7368) and then stimulated with SP. RESULTS: We detected expression of NK1R, neurokinin receptor 2 (NK2R), and neurokinin receptor 3 (NK3R) in AF and NP cells. Treatment of disc cells with the NK1R antagonist was able to suppress expression of IL-1ß, IL-6, and IL-8 in a dose-dependent manner. SP stimulation increased phosphorylation of p38-MAPK and ERK1/2, but not of NFκB p65. This indicates that p38-MAPK and ERK1/2 control SP-induced cytokine expression independently from NF-kB p65. Inhibition of p38 and ERK1/2 activation reduced SP-induced IL-6 production in human disc cells. CONCLUSION: NK1R is responsible for the proinflammatory effect of SP on IVD cells and this effect can be blocked by preventing binding of SP to NK1R. This study shows for the first time that SP mediates signaling in disc cells through NK1R and that SP activates the proinflammatory p38-MAPK and ERK1/2 pathways. LEVEL OF EVIDENCE: 4.

Anterior lumbar spine surgery: a systematic review and meta-analysis of associated complications.

BACKGROUND CONTEXT: The anterior approach to the lumbar spine is increasingly used to accomplish various surgical procedures. However, the incidence and risk factors for complications associated with anterior lumbar spine surgery (ALS) have not been fully elucidated. PURPOSE: To identify and document types of complications and complication rates associated with ALS, determine risk factors for these events, and evaluate the effect of measures used to decrease complication rates. STUDY DESIGN: Systematic review and meta-analysis. METHODS: A systematic review of the English-language literature was conducted for articles published between January 1992 and December 2013. A MEDLINE search was conducted to identify articles reporting complications associated with ALS. For each complication, the data were combined using a generalized linear mixed model with a binomial probability distribution and a random effect based on the study. Predictors used were the type of procedure (open, minimally invasive, or laparoscopic), the approach used (transperitoneal vs. retroperitoneal), use of recombinant bone morphogenetic protein-2, use of preoperative computed tomography angiography (CTA), and the utilization of an access surgeon. Open surgery was used as a reference category. RESULTS: Seventy-six articles met final inclusion criteria and reported complication rates in 11,410 patients who underwent arthrodesis and/or arthroplasty via laparoscopic, mini-open, and open techniques. The overall complication rate was 14.1%, with intraoperative and postoperative complication rates of 9.1% and 5.2%, respectively. Only 3% of patients required reoperation or revision procedures. The most common complications reported were venous injury (3.2%), retrograde ejaculation (2.7%), neurologic injury (2%), prosthesis related (2%), postoperative ileus (1.4%), superficial infection (1%), and others (1.3%). Laparoscopic and transperitoneal procedures were associated with higher complication rates, whereas lower complication rates were observed in patients receiving mini-open techniques. Our analysis indicated that the use of recombinant bone morphogenetic protein-2 was associated with increased rates of retrograde ejaculation; however, there may be limitations in interpreting these data. Data regarding the use of preoperative CTA and an access surgeon were limited and demonstrated mixed benefit. CONCLUSIONS: Overall complication rates with ALS are relatively low, with the most common complications occurring at a rate of 1% to 3%. Complication rates are related to surgical technique, approach, and implant characteristics. Further randomized controlled trials are needed to validate the use of preventative measures including CTA and the use of an access surgeon.

Revision surgery for failed cervical spine reconstruction: review article.

BACKGROUND: As the number of cervical spine procedures performed continues to increase, the need for revision surgery is also likely to increase. Surgeons need to understand the etiology of post-surgical changes, as well as have a treatment algorithm when evaluating these complex patients. QUESTIONS/PURPOSES: This study aims to review the rates and etiology of revision cervical spine surgery as well as describe our treatment algorithm. METHODS: We used a narrative and literature review. We performed a MEDLINE (PubMed) search for "cervical" and "spine" and "revision" which returned 353 articles from 1993 through January 22, 2014. Abstracts were analyzed for relevance and 32 articles were reviewed. RESULTS: The rates of revision surgery on the cervical spine vary by the type and extent of procedure performed. Patient evaluation should include a detailed history and review of the indication for the index procedure, as well as lab work to rule out infection. Imaging studies including flexion/extension radiographs and computed tomography are obtained to evaluate potential pseudarthrosis. Magnetic resonance imaging is helpful to evaluate the disc, neural elements, soft tissue, and to differentiate scar from infection. Sagittal alignment should be corrected if necessary. CONCLUSIONS: Recurrent or new symptoms after cervical spine reconstruction can be effectively treated with revision surgery after identifying the etiology, and completing the appropriate workup.

Clinical and radiographic degenerative spondylolisthesis (CARDS) classification.

BACKGROUND CONTEXT: Lumbar degenerative spondylolisthesis (DS) is a common, acquired condition leading to disabling back and/or leg pain. Although surgery is common used to treat patients with severe symptoms, there are no universally accepted treatment guidelines. Wide variation in vertebral translation, disc collapse, sagittal alignment, and vertebral mobility suggests this is a heterogeneous disease. A classification scheme would be useful to differentiate homogenous subgroups that may benefit from different treatment strategies. PURPOSE: To develop and test the reliability of a simple, clinically useful classification scheme for lumbar DS. STUDY DESIGN: Retrospective case series. PATIENT SAMPLE: One hundred twenty-six patients. OUTCOME MEASURES: Proposed radiographic classification system. METHODS: A classification system is proposed that considers disc space height, sagittal alignment and translation, and the absence or presence of unilateral or bilateral leg pain. Test cases were graded by six observers to establish interobserver reliability and regraded in a different order 1 month later to establish intraobserver reliability using Kappa analysis. To establish the relative prevalence of each subtype, a series of 100 consecutive patients presenting with L4-L5 DS were classified. RESULTS: Four radiographic subtypes were identified: Type A: advanced Disc space collapse without kyphosis; Type B: disc partially preserved with translation of 5 mm or less; Type C: disc partially preserved with translation of more than 5 mm; and Type D: kyphotic alignment. The leg pain modifier 0 denotes no leg pain, 1 denotes unilateral leg pain, and 2 represents bilateral leg pain. The Kappa value describing interobserver reliability was 0.82, representing near-perfect agreement. Intraobserver reliability analysis demonstrated Kappa=0.83, representing near-perfect agreement. Grading of the consecutive series of 100 patients revealed the following distribution: 16% Type A, 37% Type B, 33% Type C, and 14% Type D. CONCLUSIONS: A new radiographic and clinical classification scheme for lumbar DS with high inter- and intraobserver reliabilites is proposed. Use of this classification scheme should facilitate communication to enhance the quality of outcomes research on DS.

Which Variables Are Associated With Patient-reported Outcomes After Discectomy? Review of SPORT Disc Herniation Studies.

BACKGROUND: The Spine Patient Outcomes Research Trial (SPORT) evaluated the effects of surgery versus nonoperative treatment for lumbar intervertebral disc herniation (IDH), among other pathologies. Multiple subgroup analyses have been completed since the initial publications, which have further defined which patient factors lead to better or worse patient-reported outcomes; however, the degree to which these factors influence patient-reported outcomes has not been explored. QUESTIONS/PURPOSES: We reviewed the subgroup analyses of the SPORT IDH studies to answer the following questions: (1) What factors predicted improvement in patient-reported outcomes after operative or nonoperative treatment of lumbar IDH? (2) What factors predicted worse patient-reported outcomes compared to baseline after operative or nonoperative treatment of lumbar IDH? And (3) what factors influenced patient-reported outcomes of surgery in patients with lumbar IDH? METHODS: We conducted a MEDLINE(®) search to identify the subgroup analyses of the SPORT IDH data that were responsive to our study questions. Eleven articles were identified that met our search criteria. RESULTS: The patient factors associated with larger improvements in Oswestry Disability Index at 4 years with either surgical or nonoperative treatment included a higher baseline Oswestry Disability Index, BMI of less than 30, not being depressed, being insured, having no litigation pending, not having workers compensation, and having symptoms for less than 6 weeks, though there were others. Factors leading to improvement with surgical treatment were mostly related to anatomic characteristics of the disc herniation such as posterolateral and sequestered herniations. There were no patient or clinical factors identified that were associated with worse patient-reported outcomes compared to baseline after either operative or nonoperative treatment. At 2-year followup, the treatment effects were greater for those patients with upper-level herniations, patients not receiving workers compensation, and nondiabetic patients. In a 4-year multivariate analysis, being married, without joint problems, and having worse symptoms at baseline resulted in greater treatment effect with surgery. CONCLUSIONS: While most patients with IDH will likely see improvement with either surgical or nonoperative treatment, there are patient-related factors that can help predict which subgroups will demonstrate a greater improvement with surgery, such as not having joint problems, being married, having worsening symptoms at baseline, and not having diabetes. These results can help providers and patients when discussing treatment options. LEVEL OF EVIDENCE: Level I, therapeutic study. See Instructions for Authors for a complete description of levels of evidence.

Variation in the management of thoracolumbar trauma and postoperative infection.

STUDY DESIGN: Multinational survey of spine trauma surgeons. OBJECTIVES: To survey spine trauma surgeons, examine the variety of management practices for thoracolumbar fractures, and investigate the need for future areas of study. BACKGROUND: Attempts to develop a universal thoracolumbar classification system represent the first step in standardizing treatment of thoracolumbar injuries, but there is little consensus regarding diagnosis and management of these injuries. METHODS: A survey questionnaire regarding a fictional neurologically intact patient with a burst fracture was administered to 46 spine surgeons. The questionnaire consisted of 2 domains: management of thoracolumbar fractures and management of postoperative infection. Survey results were compiled and evaluated and consensus arbitrarily assumed when the majority of surgeons agreed on a single question answer. RESULTS: Although majority consensus was reached on most questions, the interobserver reliability was poor. Consensus was achieved that magnetic resonance imaging should be performed during initial imaging. The majority would also operate regardless of magnetic resonance imaging findings, and would not operate at night. The favored technique was a posterior approach with decompression. Percutaneous fusion was considered a viable option by the majority of surgeons. No consensus was reached regarding instrumentation levels or construct length. The majority would use posterolateral bone grafting, and would not remove instrumentation nor perform an anterior reconstruction. Consensus was reached that postoperative bracing is unnecessary. Regarding management of infection, consensus was reached to use intraoperative vancomycin powder but not culture the nares before surgery. The majority used a set time period for antibiotic treatment when a drain was required, and would not apply supplementary bone graft at the time of final debridement and closure. CONCLUSIONS: There is lack of consensus regarding the appropriate management of thoracolumbar fractures. In the future, multicenter prospective studies are necessary to establish guidelines for the management of thoracolumbar fractures.

Differential gene expression in anterior and posterior annulus fibrosus.

STUDY DESIGN: Laboratory study. OBJECTIVE: To evaluate the differential gene expression of cytokines and growth factors in anterior versus posterior annulus fibrosus (AF) intervertebral disc (IVD) specimens. SUMMARY OF BACKGROUND DATA: Histological analysis has demonstrated regional differences in vascular and neural ingrowth in the IVD, and similar differences may exist for cytokine and growth factor expression in patients with degenerative disc disease (DDD). Regional expression of these cytokines may also be related to the pain experienced in DDD. METHODS: IVD tissue was obtained from patients undergoing anterior lumbar interbody fusion surgery for back pain with radiological evidence of disc degeneration. For a control group, the discs of patients undergoing anterior lumbar discectomy for degenerative scoliosis were obtained as well. The tissue was carefully removed and separated into anterior and posterior AF. After tissue processing, an antibody array was completed to determine expression levels of 42 cytokines and growth factors. RESULTS: Nine discs from 7 patients with DDD and 5 discs from 2 patients with scoliosis were analyzed. In the DDD group, there were 10 cytokines and growth factors with significantly increased expression in the posterior AF versus the anterior AF ([interleukin] IL-4, IL-5, IL-6, M-CSF, MDC, tumor necrosis factor ß, EGF, IGF-1, angiogenin, leptin). In the scoliosis group, only angiogenin and PDGF-BB demonstrated increased expression in the posterior AF. No cytokines or growth factors had increased expression in the anterior AF compared with posterior AF. CONCLUSION: The posterior AF expresses increased levels of cytokines and growth factors compared with the anterior AF in patients with DDD. This differential expression may be important for targeting treatment of painful IVDs. LEVEL OF EVIDENCE: N/A.

Intramedullary nailing of diaphyseal femur fractures secondary to gunshot wounds: predictors of postoperative malrotation.

OBJECTIVES: The purpose of this study was to determine significant factors that may impact the postoperative differences in femoral version (DFV) and differences in femoral length (DFL) between the fixed and uninjured sides after intramedullary nailing (IMN) secondary to gunshot wounds. DESIGN: Retrospective data registry study. SETTING: Academic level I trauma center. PATIENTS: Over a 10-year period, 417 patients underwent IMN of a diaphyseal femur fracture (OTA/AO 32A-C). Of these, 57 patients sustained fractures caused by gunshots and had a postoperative computed tomographic scanogram. MAIN OUTCOME MEASURES: DFV and DFL. The effect of the following variables on DFV and DFL were determined through univariate and stepwise multivariate regression analyses: age, sex, body mass index, trauma fellowship-trained versus nontrauma surgeon, daytime versus nighttime surgery, antegrade versus retrograde nail insertion, use of traction, type of operating table, and AO and Winquist classifications. RESULTS: The mean postoperative DFV for all patients was 8.62 degrees (±6.67 degrees). Postoperative DFV greater than 15 degrees was found in 12.3% of all patients. After IMN, no significant differences in DFV were found with increasing complexity of AO/OTA or Winquist fracture classification. None of the aforementioned independent variables were significantly predictive of postoperative DFV in univariate or multivariate analyses. The mean postoperative DFL for all patients was 5.25 mm (±4.36 mm). In a multivariate model, classification as Winquist type 3 or 4 was weakly (adjusted R = 0.075) but significantly predictive of less DFL than categorization as type 1 or 2 (P = 0.027). CONCLUSIONS: Although gunshot-associated femur fractures may present surgical challenges for treatment through IMN, acceptable femoral rotation and length are obtainable regardless of the fracture complexity or a variety of demographic and surgically-related variables. LEVEL OF EVIDENCE: Prognostic level II.