Faculty Bibliography

PURPOSE:This study aimed to evaluate facet joint parameters and osteoarthritis grades, and segmental angular and translational motions among different grades of L5/S1 intervertebral disc (IVD) degeneration. METHODS:This retrospective study analysed kinematic magnetic resonance imaging (kMRI) images of the lumbar spine of 214 patients with low back pain. Degenerations of the L5/S1 IVDs and facet joints osteoarthritis were assessed using the Pfirrmann and Pathria grading scales, respectively. Facet joint parameters included facet joint angle and facet joint space width. Angular and translation segmental motions were measured using MRI Analyzer software. RESULTS:The mean age of the studied patients was 44.1 ± 13.9 years. Patients with L5/S1 disc degeneration were associated with higher odds of facet joint osteoarthritis (odds ratio = 2.28, 95% confidence interval = 1.23-4.23, P = 0.008). There was a positive correlation between L5/S1 disc degeneration grade and the facet joint grade (r = 0.365, P > 0.001). Grade IV facet joint osteoarthritis did not appear in grades I or II disc degeneration (P > 0.001). The average facet joint width decreased significantly with increasing Pfirrmann grading (P = 0.017). The difference in facet joint angle between groups was not statistically significant (P = 0.532). The differences in the angular and translational motions were not statistically significant (P = 0.530, and 0.510, respectively). CONCLUSION:A positive correlation exists between L5/S1 disc degeneration and facet joint osteoarthritis grades. The facet joint space width decreases significantly with increasing grade of disc degeneration.

STUDY DESIGN/METHODS:Retrospective review of insurance database. PURPOSE/OBJECTIVE:To investigate national trends, complications, and costs after cervical disc replacement (CDR) using an administrative insurance database representative of the United States population. OVERVIEW OF LITERATURE/BACKGROUND:As CDR continues to be used to treat patients with cervical stenosis, it is important to gain a better understanding of its use on a national level, potential complications, and cost. This information will allow for optimal patient counseling, risk stratification, and healthcare cost assessments. Several prior studies have investigated complications associated with CDR, but they have been limited by small sample size, single institution experiences, limited follow-up, and potential conflicts of interest. METHODS:Patients who underwent single or multilevel CDR between 2007 and 2015 were identified using an insurance database. We collected data on annual trends, reimbursement costs, patient demographic information, hospital information, and information on complications from the time of operation to 1 year postoperative. RESULTS:Total of 293 patients underwent either single or multilevel CDR. The number of procedures increased nonlinearly over time at an average of 17% per year, with a greater increase seen in the outpatient setting. Less than 3.7% of patients had new onset pain within 1 year after CDR. Within 1 year, 12.3% of patients reported a mechanical and/or bone-related complication. There were no patients who indicated a new nerve injury within 6 months of follow-up. Less than 3.7% of patients presented with dysphagia or dysphonia within 6 months, infection within 3 months, or a revision or reoperation within 1 year. Average reimbursement for single-level inpatient versus outpatient CDR was US $33,696.28 and US $34,675.12, respectively (p=0.29). CONCLUSIONS:This study demonstrated that the use of CDR continued to increase. The most common complication was mechanical and/or bone-related, and cost analysis demonstrated no significant difference between inpatient and outpatient CDR.

STUDY DESIGN/UNASSIGNED:Classification development. OBJECTIVES/UNASSIGNED:The aim of our study was to develop a 3-tier classification for the levels of evidence for osteobiologics and provide a description of the principles by which osteobiologics can be evaluated. BOnE (Bone Osteobiologics and Evidence) classification evaluates each osteobiologic based on the available evidence, and if the published evidence is based on clinical, in vivo or in vitro studies. METHODS/UNASSIGNED:The process of establishing the BOnE classification included 5 face-to-face meetings and 2 web calls among members of the AOSpine Knowledge Forum Degenerative. RESULTS/UNASSIGNED:The 3 levels of evidence were determined based on the type of data on osteobiologics: level A for human studies, level B for animal studies, and level C for in vitro studies, with level A being the highest level of evidence. Each level was organized into 4 subgroups (eg, A1, A2, A3, and A4). CONCLUSIONS/UNASSIGNED:The use and the variety of osteobiologics for spine fusion has dramatically increased over the past few decades; however, literature on their effectiveness is inconclusive. Several prior systematic reviews developed by AOSpine Knowledge Forum Degenerative reported low level of evidence primarily due to the high risk of bias, small sample size, lack of control groups, and limited patient-reported outcomes. BOnE classification will provide a universal platform for research studies and journal publications to classify a new or an existing product and will allow for creating decision-making algorithms for surgical planning.

STUDY DESIGN/UNASSIGNED:Systematic literature review. OBJECTIVE/UNASSIGNED:Our primary objective was to compare reported fusion rates after anterior cervical discectomy and fusion (ACDF) using structural allograft versus polyetheretherketone (PEEK) interbody devices in patients with cervical spine degeneration. Our secondary objectives were to compare differences in rates of subsidence and reoperation and in patient-reported outcomes between the 2 groups. METHODS/UNASSIGNED:Through a systematic review of the English-language literature using various databases, we identified 4702 articles. After we applied inclusion and exclusion criteria, 14 articles (7 randomized controlled trials, 4 prospective studies, and 3 retrospective studies) reporting fusion rates of structural allograft or PEEK interbody devices were eligible for our analysis. No randomized controlled trials compared outcomes of structural allograft versus PEEK interbody devices. Extracted data included authors, study years, study designs, sample sizes, patient ages, duration of follow-up, types of interbody devices used, fusion rates, definition of fusion, reoperation rates, subsidence rates, and patient-reported outcomes. RESULTS/UNASSIGNED:Fusion rates were 82% to 100% for allograft and 88% to 98% for PEEK interbody devices. The reported data were insufficient to perform meta-analysis. Structural allograft had the highest reported rate of reoperation (14%), and PEEK interbody devices had the highest reported subsidence rate (18%). Patient-reported outcomes improved in both groups. There was insufficient high-quality evidence to compare the associations of various PEEK modifications with fusion rates. CONCLUSION/UNASSIGNED:Fusion rates were similar between structural allograft and PEEK interbody devices when used for ACDF for cervical spine degeneration. Currently, there is insufficient high-quality evidence to assess associations of PEEK modifications with fusion rates. LEVEL OF EVIDENCE/UNASSIGNED:II.

PURPOSE OF REVIEW/OBJECTIVE:To provide information on characteristics and use of various ceramics in spine fusion and future directions. RECENT FINDINGS/RESULTS:In most recent years, focus has been shifted to the use of ceramics in minimally invasive surgeries or implementation of nanostructured surface modification features to promote osteoinductive properties. In addition, effort has been placed on the development of bioactive synthetics. Core characteristic of bioactive synthetics is that they undergo change to simulate a beneficial response within the bone. This change is based on chemical reaction and various chemical elements present in the bioactive ceramics. Recently, a synthetic 15-amino acid polypeptide bound to an anorganic bone material which mimics the cell-binding domain of type-I collagen opened a possibility for osteogenic and osteoinductive roles of this hybrid graft material. Ceramics have been present in the spine fusion arena for several decades; however, their use has been limited. The major obstacle in published literature is small sample size resulting in low evidence and a potential for bias. In addition, different physical and chemical properties of various ceramics further contribute to the limited evidence. Although ceramics have several disadvantages, they still hold a great promise as a value-based graft material with being easily available, relatively inexpensive, and non-immunogenic.

The purpose of this study was to assess trends in the use of perioperative single and continuous peripheral nerve blocks (PNBs) and their associations with emergency department (ED) visits after arthroscopic rotator cuff repair (RCR) surgery. The authors used a large database from a private insurer to identify patients who received perioperative PNBs for arthroscopic RCR surgeries from 2007 to 2015. They analyzed patient demographics as well as trends in perioperative PNB use. They also assessed rates of single shot vs continuous PNB use and compared rates of postoperative ED visits according to PNB type. The rate of perioperative PNB for arthroscopic RCR was higher than previously reported (65.9%) and increased over time (52.8% in 2007 to 64.6% in 2015; P=.029). Single shot PNBs were more common than continuous, catheter-mediated PNBs (60.0% vs 6.6%; P<.001), although the use of continuous blocks increased at a greater rate during the study period. Patients who received a perioperative continuous PNB were significantly more likely to visit an ED within 7 days of their surgery than those who received a single shot PNB or no PNB (6.71% vs 4.78% vs 4.74%; P<.02). The rates of ED visits within each group did not change significantly over time. Continuous PNBs are increasingly common for patients undergoing arthroscopic RCR surgery but are associated with increased rates of postoperative ED visits. Studies are needed to identify the reasons for this increased rate of ED visits and strategies to decrease ED use. [Orthopedics. 2020; 43(2): 127-131.].

BACKGROUND CONTEXT:Posterior cervical foraminotomy (PCF) is a relatively safe procedure for the treatment of cervical radiculopathy. Though most often performed as an inpatient procedure, there is an increasing number of patients treated in an outpatient setting. PURPOSE:This study aimed to compare the perioperative complication rates associated with inpatient and outpatient single-level PCF. STUDY DESIGN/SETTING:Retrospective database study. PATIENT SAMPLE:Patients with cervical radiculopathy who underwent inpatient or outpatient single-level PCF between 2007 to the first quarter of 2016. OUTCOME MEASURES:Charlson Comorbidity Index (CCI) was used as a broad measure of comorbidity. Surgical complications included cervical nerve root injury, dural tear, wound complications, infection, dysphagia, cervicalgia, and revision surgery. Medical complications included pulmonary embolism and lower limb deep vein thrombosis, acute myocardial infarction, acute respiratory failure, pneumonia, sepsis, and urinary complications. METHODS:This study was a retrospective review of patients who received single-level PCF from 2007 to the first quarter of 2016 as either outpatients or inpatients using the Humana subset of the PearlDiver Patient Record Database. The incidence of perioperative medical and surgical complications was queried using relevant International Classification of Diseases (ICD-9-CM and ICD-10-CM) and Current Procedural Terminology codes. Multivariate logistic regression analysis, adjusted for age, gender, and CCI, was performed to calculate odds ratios (ORs) of complications among inpatients relative to outpatients treated with PCF. Propensity score matching was done, and comparisons were made for postoperative complications. RESULTS:Throughout the time period, 1,469 and 1,192 patients received inpatient and outpatient single-level PCF, respectively. The mean CCIs±standard deviation of inpatient and outpatient groups undergoing PCF were 2.83±3.11 and 1.46±2.21, respectively (p<.001). After propensity score matching, patients who received PCF in an inpatient setting showed significantly higher rates of wound complications (OR=1.53, 95% confidence interval [CI]=1.04-2.23; p=.029), infection (OR=1.91, CI=1.15-3.15; p=.012), acute respiratory failure (OR=2.50, CI=1.23-5.08; p=.011), and urinary tract infections and incontinence (OR=2.11, CI=1.32-3.38; p=.002). CONCLUSIONS:Outpatient single-level PCF was associated with a lower rate of perioperative medical and surgical complications. The PCF in the outpatient setting can potentially be a safe procedure for the treatment of cervical radiculopathy with appropriate patient selection.