Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccine response in adults with predominantly antibody deficiency.

Background: Patients with predominantly antibody deficiency (PAD) have lower anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike antibody levels after initial 2-dose SARS-CoV-2 vaccination than healthy controls do; however, the anti-spike antibody responses and neutralization function in patients with PAD following subsequent immunizations remain understudied. Objective: We sought to characterize anti-spike antibody responses in adults with PAD over the course of 5 SARS-CoV-2 vaccine doses and identify diagnostic and immunophenotypic risk factors for low antibody response. Methods: We evaluated anti-spike antibody levels in 117 adult patients with PAD and 192 adult healthy controls following a maximum of 5 SARS-CoV-2 immunizations. We assessed neutralization of the SARS-CoV-2 wild-type strain and the Omicron BA.5 variant and analyzed infection outcomes. Results: The patients with PAD had significantly lower mean anti-spike antibody levels after 3 SARS-CoV-2 vaccine doses than the healthy controls did (1,439.1 vs 21,890.4 U/mL [P < .0001]). Adults with secondary PAD, severe primary PAD, and high-risk immunophenotypes had lower mean anti-spike antibody levels following vaccine doses 2, 3, and/or 4 but not following vaccine dose 5. Compared with patients with mild and moderate PAD, patients with severe PAD had a higher rate of increase in anti-spike antibody levels over 5 immunizations. A strong positive correlation was observed between anti-spike antibody levels and neutralization of both the SARS-CoV-2 wild-type strain and the Omicron BA.5 variant. Most infections were managed on an outpatient basis. Conclusions: In all of the patients with PAD, anti-spike antibody levels increased with successive SARS-CoV-2 immunizations and were correlated with neutralization of both the SARS-CoV-2 wild-type strain and the Omicron BA.5 variant. Secondary PAD, severe primary PAD, and high-risk immunophenotypes were correlated with lower mean anti-spike antibody levels following vaccine doses 2 through 4. Patients with severe PAD had the highest rate of increase in anti-spike antibody levels over 5 immunizations. These data suggest a clinical benefit to sequential SARS-CoV-2 immunizations, particularly among high-risk patients with PAD.

Respiratory infections predominate after day 100 following B-cell maturation antigen-directed CAR T-cell therapy.

Infections are an important complication after B-cell maturation antigen (BCMA)-directed chimeric antigen receptor (CAR) T-cell therapy and risks may differ between the early and late periods. We evaluated infections in 99 adults who received a first BCMA-directed CAR T-cell therapy (commercial and investigational autologous BCMA CAR T-cell products at the recommended phase 2 dose) for relapsed/refractory multiple myeloma between November 2016 and May 2022. Infections were recorded until day 365, if patients experienced symptoms with a microbiologic diagnosis, or for symptomatic site-specific infections treated with antimicrobials. One-year cumulative incidence functions were calculated based on time to first respiratory infection using dates of infection-free death and receipt of additional antineoplastic therapies as competing risks. Secondary analysis evaluated risk factors for late respiratory infections using univariate and multivariable Cox regression models. Thirty-seven patients (37%) experienced 64 infectious events over the first year after BCMA-directed CAR T-cell therapy, with 42 early infectious events (days, 0-100), and 22 late infectious events (days, 101-365). Respiratory infections were the most common site-specific infection and the relative proportion of respiratory infections increased in the late period (31% of early events vs 77% of late events). On multivariable analysis, hypogammaglobulinemia (hazard ratio [HR], 6.06; P = .044) and diagnosis of an early respiratory viral infection (HR, 2.95; P = .048) were independent risk factors for late respiratory infection. Respiratory infections predominate after BCMA CAR T-cell therapy, particularly after day 100. Hypogammaglobulinemia and diagnosis of an early respiratory infection are risk factors for late respiratory infections that may be used to guide targeted preventive strategies.

Factors predicting health-related quality of life of the Malaysian B40 school-aged children living in urban-poor flats in the central region of Malaysia.

BACKGROUND AND OBJECTIVES: Health-related quality of life (HRQoL) is a multidimensional concept that indicated an individual's holistic health, whereby the urban-poor community are susceptible to low HRQoL due to their high vulnerability. This study aimed to determine factors that predicted the HRQoL among the urban-poor school-aged children. METHODS AND STUDY DESIGN: This is a cross-sectional study and a total of 408 primary school-aged children (male: 72.3%; female: 27.7%), with a mean age of 9.68±1.48 years, were recruited from 10 urban-poor flats through cluster sampling at the central region of Malaysia. Their anthropometry, nutrition knowledge, attitude and practice, physical activity, dietary practices, and HRQoL were assessed. RESULTS: A quarter (24.5%) of the urban-poor children were either overweight or obese in the present study. The HRQoL total score among the urban-poor children was 65.0±18.5. The result of multiple linear regression analysis shown that higher nutrition attitude (B=0.34, p=0.001) and practices (B=0.39, p=0.001), higher physical activity (B=3.73, p=0.004), higher lunch intake (B=1.35, p<0.001), lower supper intake (B=-1.35, p<0.001), and lower fast-food intake (B=-1.61, -1.17, p<0.001) are the significant predictors of better HRQoL among the urban-poor children (R2=0.32, F(8,399)=23.72, p<0.001). CONCLUSIONS: Future studies should focus on these predictors to formulate interventions that could enhance the HRQoL among the Malaysian urban-poor children.

Quinolinic acid, a kynurenine/tryptophan pathway metabolite, associates with impaired cognitive test performance in systemic lupus erythematosus.

OBJECTIVES: Interferon-alpha, an important contributor to SLE pathogenesis, induces the enzyme indoleamine 2,3-dioxygenase in the kynurenine/tryptophan (KYN/TRP) pathway. This leads to a potentially neurotoxic imbalance in the KYN/TRP pathway metabolites, quinolinic acid (QA), an N-methyl D-aspartate glutamatergic receptor (NMDAR) agonist, and kynurenic acid (KA), an NMDAR antagonist. We determined whether QA/KA ratios associate with cognitive dysfunction (CD) and depression in SLE. METHODS: This cross-sectional study included 74 subjects with SLE and 74 healthy control (HC) subjects; all without history of neuropsychiatric disorders. Serum metabolite levels (KYN, TRP, QA, KA) were measured concurrently with assessments of cognition (Automated Neuropsychological Assessment Metrics (ANAM), 2×2 array), mood and pain, and compared between SLE and HC. Multivariable modelling in SLE was used to evaluate associations of metabolites with cognitive performance and depression. RESULTS: Serum KYN/TRP and QA/KA ratios were elevated in SLE versus HC (p<0.0001). SLE performed worse than HC on four of five ANAM tests (all p≤0.02) and the 2×2 array (p<0.01), and had higher depression scores (p<0.01). In SLE, elevated QA/KA ratios correlated with poor performance on Match to Sample (MTS), a working memory and visuospatial processing task (p<0.05). Subjects with SLE with elevated QA/KA ratios also had slightly higher odds of depression, but this did not reach significance (p=0.09). Multivariable modelling in SLE confirmed an association between QA/KA ratios and poor MTS performance when considering potentially confounding factors (p<0.05). CONCLUSIONS: Elevated serum KYN/TRP and QA/KA ratios confirm KYN/TRP pathway activation in SLE. The novel association between increased QA/KA ratios and poor cognitive performance supports further study of this pathway as a potential biomarker or therapeutic target for SLE-mediated CD.

Cetirizine as a Causative Agent for Drug Induced Methemoglobinemia: A Case Report and Review.

A case of methemoglobinemia (MHb) in a teenage woman, triggered by an acute ingestion of approximately 120 to 180 mg of cetirizine, allegedly, with no suicidal intent is described. The patient presented with anxiety and tremors and rapidly developed central cyanosis unresponsive to oxygen supplementation. There was a history of recurrent, spontaneously remitting, unprovoked "blue discoloration of hands." Investigations confirmed the diagnosis of MHb, and the patient responded to ascorbic acid and methylene blue, although the baseline methemoglobin level remained slightly high. The exact enzymatic deficiency could not be ascertained as the patient refused to undergo complete testing. To the best of our knowledge, this is the first documentation of cetirizine as a causative agent for drug induced MHb. Cetirizine, a selective histamine H1 receptor antagonist is eliminated via oxidation and conjugation processes, which use pathways other than cytochrome P450 enzyme system. The metabolism could potentially create by-products, like superoxide or hydrogen peroxide, which could act as strong reducing agents and oxidize hemoglobin into ferric containing methemoglobin. In this case, an unusually high systemic load of the drug speculatively saturated and overwhelmed the protective enzyme systems, which resulted in clinical manifestation of MHb.

Vancomycin volume of distribution estimation in adults with class III obesity.

PURPOSE: To compare methods of estimating vancomycin volume of distribution (V) in adults with class III obesity. METHODS: A retrospective, multicenter pharmacokinetic analysis of adults treated with vancomycin and monitored through measurement of peak and trough concentrations was performed. Individual pharmacokinetic parameter estimates were obtained via maximum a posteriori Bayesian analysis. The relationship between V and body weight was assessed using linear regression. Mean bias and root-mean-square error (RMSE) were calculated to assess the precision of multiple methods of estimating V. RESULTS: Of 241 patients included in the study sample, 159 (66.0%) had a body mass index (BMI) of 40.0-49.9 kg/m2, and 82 (34.0%) had a BMI of ≥50.0 kg/m2. The median (5th, 95th percentile) weight of patients was 136 (103, 204) kg, and baseline characteristics were similar between BMI groups. The mean ± S.D. V was lower in patients with a BMI of 40.0-49.9 kg/m2 than in those with a BMI of ≥50.0 kg/m2 (72.4 ± 19.6 L versus 79.3 ± 20.6 L, p = 0.009); however, body size poorly predicted V in regression analyses (R2 < 0.20). A fixed estimate of V (75 L) and use of a weight-based value (0.52 L/kg by total body weight [TBW]) yielded similar bias and error in this population. CONCLUSION: Results of the largest analysis of vancomycin V in class III obesity to date indicated that use of a fixed V value (75 L) and use of a TBW-based estimate (0.52 L/kg) for estimation of vancomycin V in patients with a BMI of ≥40.0 kg/m2 have similar bias. Two postdistribution vancomycin concentrations are needed to accurately determine patient-specific pharmacokinetic parameters, estimate area under the curve, and improve the precision of vancomycin dosing in this patient population.

Dosing vancomycin in the super obese: less is more.

Background: Vancomycin remains the mainstay of empirical therapy directed against MRSA. National guidelines recommend empirical dosing based on total body weight with trough-level therapeutic drug monitoring (TDM), which may not be optimal in obese and super obese patients. Furthermore, nomograms for empirical vancomycin dosing by estimated kidney function pre-date standardization of creatinine assays. Objectives: To determine an empirical vancomycin dosing strategy for obese and super obese adults that is consistent with the AUC monitoring paradigm. Methods: We conducted a population pharmacokinetic study using data obtained from routine peak and trough TDM of vancomycin in obese and super obese adults. An empirical dosing nomogram was developed using Monte Carlo simulation to identify vancomycin doses that optimize the probability of efficacy and minimize the probability of acute kidney injury based on AUC. Results: A total of 346 patients were included encompassing a wide range of body weight (69.6-293.6 kg) and BMI (30.1-85.7 kg/m2) values. In the final model, vancomycin clearance (CLV) was described using a linear combination of age, serum creatinine, sex and allometrically scaled body weight. Monte Carlo simulation demonstrated that maintenance doses >4500 mg/day were not required to achieve pharmacodynamic AUC targets in obese and super obese patients at clinically relevant values of CLV. Conclusions: Empirical vancomycin dosing informed by common clinical variables, including standardized creatinine, with subsequent individualization using AUC-targeted TDM can optimize therapy in obese and super obese adults.

Peak Measurement for Vancomycin AUC Estimation in Obese Adults Improves Precision and Lowers Bias.

Vancomycin area under the curve (AUC) estimates may be skewed in obese adults due to weight-dependent pharmacokinetic parameters. We demonstrate that peak and trough measurements reduce bias and improve the precision of vancomycin AUC estimates in obese adults (n = 75) and validate this in an independent cohort (n = 31). The precision and mean percent bias of Bayesian vancomycin AUC estimates are comparable between covariate-dependent (R2 = 0.774, 3.55%) and covariate-independent (R2 = 0.804, 3.28%) models when peaks and troughs are measured but not when measurements are restricted to troughs only (R2 = 0.557, 15.5%).

Individualized vancomycin dosing in obese patients: a two-sample measurement approach improves target attainment.

STUDY OBJECTIVE: To compare the likelihood of vancomycin target trough concentration attainment based on infectious diagnosis and/or minimum inhibitory concentration for the organism by using a two-sample approach versus the prior institutional standard of a trough-only approach in obese patients receiving vancomycin. DESIGN: Preintervention and postintervention study. SETTING: Community acute care hospital. PATIENTS: One hundred fifty hospitalized adults with a body mass index (BMI) of 30 kg/m(2) or greater and treated with vancomycin for at least 48 hours between July 2013 and March 2014 were evaluated to compare the frequency of steady-state therapeutic trough concentration attainment between two approaches: a trough-only dosing method (preintervention group [75 patients]) and a dosing strategy measuring two vancomycin serum concentrations during the elimination phase (peak and trough) to calculate pharmacokinetic parameters and individualize the maintenance regimen (postintervention group [75 patients]). Data for the preintervention group were retrospectively retrieved from a 4-month period for patients admitted between July and October 2013, prior to implementation of the two-point vancomycin dosing protocol. Initial vancomycin empiric dose selection for both groups utilized the same population-based pharmacokinetic equations. MEASUREMENTS AND MAIN RESULTS: Median (5th-95th percentile) age, weight, and BMI were 59 (34-80) years, 105 (79.8-164) kg, and 34.5 (30.0-55.1) kg/m(2) , respectively, for all patients. The percentages of initial therapeutic trough concentrations achieved in the preintervention and postintervention groups were 32.0% and 42.7%, respectively (p=0.117). For patients with a second trough measurement, 31.0% in the preintervention group and 65.2% in the postintervention group were within the therapeutic range (p=0.024). CONCLUSION: Measurement of two serum vancomycin concentrations significantly improves subsequent target trough concentration attainment in the obese population.

Cancer care in East and Central Harlem: community partnership needs assessment.

In the largely African American and Hispanic communities of East and Central Harlem in New York City (NYC), health inequities are glaring. Mortality from cancer is 20-30 % higher than in Manhattan and 30-40 % higher than rates in the general population in NYC. Despite advances in risk assessment, early detection, treatment, and survivorship, individuals in Harlem and similar urban communities are not benefiting equally. Guided by community-based participatory research, this study serves as an important step in understanding cancer care needs and the range of factors that impact the disparate rates of cancer in East and Central Harlem. Forty individual interviews were conducted with community leaders and residents. Major themes included: need for appropriate supportive services; health care access and financial challenges; beliefs related to stigma, trust, and accountability; and the impact of the physical environment on health. Education was seen as a critical area of need and intervention.

Coronal deformity correction in adolescent idiopathic scoliosis patients using the fulcrum-bending radiograph: a prospective comparative analysis of the proximal thoracic, main thoracic, and thoracolumbar/lumbar curves.

The aim of the prospective, comparative radiographic analysis was to determine the role of the fulcrum-bending radiograph (FBR) for the assessment of the proximal thoracic (PT), main thoracic (MT), and the thoracolumbar/lumbar (TL/L) curves in patients undergoing posterior spinal pedicle screw fixation and fusion for adolescent idiopathic scoliosis (AIS). The FBR demonstrated statistically better correction than other preoperative methods for the assessment of frontal plane correction of the MT curves. The fulcrum-bending correction index (FBCI) has been considered a superior method than the correction rate for comparing curve correction undergoing posterior spinal fusion because it accounts for the curve flexibility. However, their applicability to assess the PT and TL/L curves in AIS patients remains speculative. The relation between FBR and correction obtained by pedicle screws fixation is still unknown. Thirty-eight consecutive AIS patients who underwent pedicle screw fixation and posterior fusion were included in this study. The assessment of preoperative radiographs included standing posterior-anterior (PA), FBR, supine side-bending, and postoperative standing PA and lateral plain radiographs. The flexibility of the curve, as well as the FBCI, was calculated for all patients. Postoperatively, radiographs were assessed at immediate (i.e. 1 week), 3-month, 6-month, 12-month, and 2-year follow-up. Cobb angles were obtained from the PT, MT, and TL/L curves. The study consisted of 9 PT, 37 MT, and 12 TL/L curves, with a mean age of 15.1 years. The mean FBR flexibility of the PT, MT, and the TL/L curves was 42.6, 61.1, and 66.2%, respectively. The mean operative correction rates in the PT, MT, and TL/L curves were 43.4, 69.3, and 73.9%, respectively, and the mean FBCI was 103.8, 117.0, and 114.8%, respectively. Fulcrum-bending flexibility was positively correlated with the operative correction rate in PT, MT, and TL/L curves. Although the correction rate in MT and TL/L curves was higher than PT curves, the FBCI in PT, MT, and TL/L curves was not significantly different (p < 0.05). The FBR can be used to assist in the assessment of PT, MT, and TL/L curve corrections in AIS patients. When curve flexibility is taken into account by FBR, the ability of pedicle screws to correct PT, MT, and TL/L curves is the same.

A multicenter study to evaluate the safety and efficacy of a stand-alone anterior carbon I/F Cage for anterior lumbar interbody fusion: two-year results from a Food and Drug Administration investigational device exemption clinical trial.

STUDY DESIGN: Two-year prospective multicenter clinical trial. OBJECTIVE: To determine the safety and efficacy of the anterior I/F Cage in the primary treatment of single-level degenerative disc disease. SUMMARY OF BACKGROUND DATA: A carbon fiber-reinforced polymer cage was designed to replace the traditional allograft/autograft structural graft used in an anterior lumbar interbody fusion (ALIF). Although the outcomes of various types of ALIF cages have previously been reported, the safety and efficacy of the I/F cage are unknown. METHODS: Between June 2000 and June 2004, 112 patients were prospectively enrolled at 12 study sites for the current study. Efficacy was evaluated clinically and radiographically. "Patient success" was declared only when the following 4 criteria were present at final follow-up: (1) "clinical success": improvement of 15 points on Oswestry Disability Index, (2) absence of a new neurologic abnormality, (3) successful radiographic fusion, and (4) no subsequent secondary surgical intervention at 24-month follow-up. Safety was inferred by way of an objective summary of complications and adverse events, as reported at regular intervals throughout the course of the study. RESULTS: A total of 112 patients (mean age: 41.7 years) underwent a single-level ALIF procedure (L5-S1: 95 patients, L4-L5: 17 patients). The mean surgical time was 126 minutes, the mean estimated blood loss was 134 mL, and the mean duration of hospitalization was 3.3 days. There were 80 patients available for 24-month follow-up. Overall patient success was 25% (20/80). Clinical success was present in 46.3% (37/80), fusion success was 57.5% (46/80), and 87.5% of patients (70/80) avoided a subsequent secondary surgical intervention. Disc space height had significantly increased after surgery, and this increase was maintained at 2 years follow-up period. Complications and adverse events included the following: 8 infections (7.1%) (7 superficial, 1 deep), 2 vascular injuries (1.8%) (left common iliac vein), and 12 secondary surgical interventions (15%). CONCLUSION: This safety and efficacy study suggests that the anterior I/F Cage is a safe surgical option in the treatment of single-level lumbar degenerative disc disease. As a stand-alone construct, the I/F Cage yields suboptimal radiographic and clinical outcomes. Additional benefit may be gained from adjunctive posterior stabilization.

Immunogenicity of osteogenic protein 1: results from a prospective, randomized, controlled, multicenter pivotal study of uninstrumented lumbar posterolateral fusion.

OBJECT: The aim in this study was to detect and quantify antibody responses against recombinant human osteogenic protein 1 (OP-1) and to compare these responses to patient clinical outcomes and safety information. METHODS: A controlled, open-label, randomized, prospective, multicenter pivotal study was performed in which patients with single-level Grade I or II degenerative lumbar spondylolisthesis (Meyerding classification) and spinal stenosis underwent decompression and uninstrumented posterolateral spinal arthrodesis. Three hundred thirty-six patients were randomized in a 2:1 fashion to receive either OP-1 Putty or autogenous iliac crest bone graft. Patients were evaluated at regular postoperative intervals for radiographic results, clinical outcomes, and safety parameters for more than 36 months. Serum samples were collected over this period and evaluated for the presence of anti­OP-1 antibodies and neutralizing activity by using a battery of in vitro binding assays (including enzyme-linked immunosorbent assay [ELISA]) and cell-based bioassays, respectively. RESULTS: Antibodies were predominantly seen in the OP-1­treated patients, although some responses were recorded preoperatively and in patients receiving autograft alone. Antibody production peaked in the 6-week to 3-month postoperative time frame and diminished thereafter. Neutralizing antibodies (Nabs) were detected at 1 time point at least in 25.6% of the patients treated with OP-1 Putty, but were not found in any patient following the 24-month postoperative time period. A single autograft patient (1.2%) also presented with OP-1 Nabs. An anti­OP-1 antibody status did not correlate with any measure of patient outcomes or adverse events. CONCLUSIONS: Recombinant human OP-1 (bone morphogenetic protein 7), like many recombinant human proteins, induces an immune response following its use as a bone graft alternative. This response was transient and diminished over time, and there was no statistical evidence to suggest an association between Nab status and any of the efficacy or safety criteria that were examined.

Pulmonary cement embolization after kyphoplasty: a case report and review of the literature.

BACKGROUND CONTEXT: Kyphoplasty is performed for the treatment of osteoporotic compression fractures. A theoretical advantage of this technique is the reduced risk of embolization of cement. STUDY DESIGN/SETTING: Case report of an incidental finding of cement pulmonary embolization after kyphoplasty of an osteoporotic vertebral compression fracture. METHODS/RESULTS: Here we report a patient who presented with an incidental finding of pulmonary embolization after kyphoplasty and review the relevant literature. CONCLUSIONS: Patients who present with symptoms of respiratory distress after kyphoplasty should undergo workup for pulmonary embolism. Clinicians may consider routine postoperative chest radiographs after kyphoplasty to screen for embolic disease. Further research is necessary to identify the risk factors and possible long-term sequelae of cement embolization.

A systematic review of occipital cervical fusion: techniques and outcomes.

OBJECT Numerous techniques have been historically used for occipitocervical fusion with varied results. The purpose of this study was to examine outcomes of various surgical techniques used in patients with various disease states to elucidate the most efficacious method of stabilization of the occipitocervical junction. METHODS A literature search of peer-reviewed articles was performed using PubMed and CINAHL/Ovid. The key words "occipitocervical fusion," "occipitocervical fixation," "cervical instrumentation," and "occipitocervical instrumentation" were used to search for relevant articles. Thirty-four studies were identified that met the search criteria. Within these studies, 799 adult patients who underwent posterior occipitocervical fusion were analyzed for radiographic and clinical outcomes including fusion rate, time to fusion, neurological outcomes, and the rate of adverse events. RESULTS No articles stronger than Class IV were identified in the literature. Among the patients identified within the cited articles, the use of posterior screw/rod instrumentation constructs were associated with a lower rate of postoperative adverse events (33.33%) (p < 0.0001), lower rates of instrumentation failure (7.89%) (p < 0.0001), and improved neurological outcomes (81.58%) (p < 0.0001) when compared with posterior wiring/rod, screw/plate, and onlay in situ bone grafting techniques. The surgical technique associated with the highest fusion rate was posterior wiring and rods (95.9%) (p = 0.0484), which also demonstrated the shortest fusion time (p < 0.0064). Screw/rod techniques also had a high fusion rate, fusing in 93.02% of cases. When comparing outcomes of surgical techniques depending on the disease status, inflammatory diseases had the lowest rate of instrumentation failure (0%) and the highest rate of neurological improvement (90.91%) following the use of screw/rod techniques. Occipitocervical fusion performed for the treatment of tumors by using screw/rod techniques had the lowest fusion rate (57.14%) (p = 0.0089). Traumatic causes of occipitocervical instability had the highest percentage of pain improvement with the use of screw/plates (100% improvement) (p < 0.0001). CONCLUSIONS Based on the existing literature, techniques that use screw/rod constructs in occipitocervical fusion are associated with very favorable outcomes in all categories assessed for all disease processes. For patients requiring occipitocervical arthrodesis for the treatment of inflammatory diseases, screw/rod constructs are associated with the most favorable outcomes, while posterior wiring and onlay in situ bone grafting is associated with the least favorable outcomes. Occipitocervical arthrodesis performed for the diagnosis of tumor is associated with the lowest rate of successful arthrodesis using screw/rod techniques, while posterior wiring and rods have the highest rate of arthrodesis. The nonspecified disease group had the lowest rate of surgical adverse events and the highest rate of neurological improvement.

Patient perception of outcomes following failed spinal instrumentation with polyetheretherketone rods and titanium rods.

STUDY DESIGN: A structured questionnaire. OBJECTIVE: The purpose of this study was to determine whether material rod composition and its imaging characteristics can determine patient perceptions of pain, outcome, and need for revision surgery in the context of the failure of spinal instrumentation following lumbar arthrodesis. SUMMARY OF BACKGROUND DATA: Patient perceptions of radiographic images in the context of failed spinal instrumentation may influence clinical outcomes and patient satisfaction. Due to radiolucency, failed polyetheretherketone (PEEK) rods may be perceived differently by patients than more traditional materials. METHODS: Patients presenting primarily with chief complaints of back pain completed a 2-page, 22-question questionnaire containing 3 alternative radiographic images of failed rod instrumentation following posterolateral lumbar arthrodesis. The images represented failed rods composed of either PEEK, PEEK with a longitudinal radio-opaque marker, or traditional titanium. Statistical analysis with the Cochran Q test was performed to determine whether there were statistical differences in the responses. RESULTS: The responses suggested a preference for the images representing PEEK instrumentation as being associated with superior clinical outcomes, the least pain, the most comfort, and the least likelihood of required revision surgery. CONCLUSION: PEEK rods possess radiolucent properties that can alter patient perceptions of clinical outcomes when compared with images of other equally unfavorable scenarios. The significance of these patient perceptions must still be demonstrated. However, they may play an important role in clinical outcomes and patient satisfaction.

Complications in the management of Charcot spinal arthropathy.

Charcot spinal arthropathy is a relatively rare, destructive process characterized by a cycle of progressive deformity, destruction, and worsening instability as a result of repetitive trauma and inflammation. It may result from nontraumatic as well as traumatic causes. Historically, patients with severe symptomatic instability have been successfully treated with combined anterior and posterior fusion techniques. The long-term outcomes and potential complications, however, have not been well reported. The authors report on 2 such cases of Charcot spinal arthropathy treated surgically, one with a traumatic and one with a nontraumatic etiology. They include the unique pitfalls encountered while treating these patients, as well as their surgical treatments, complications, and long-term results.

Complications associated with single-level transforaminal lumbar interbody fusion.

BACKGROUND CONTEXT: The transforaminal lumbar interbody fusion (TLIF) procedure has become an increasingly popular means of obtaining a circumferential fusion while avoiding the morbidity of the anterior approach. Concerns remain, however, regarding the clinical efficacy and safety of its use. PURPOSE: The purpose of this study was to evaluate the complications of the single-level TLIF procedure. The difference in complications observed with the use of iliac crest autograft compared with rhBMP-2 will be assessed. STUDY DESIGN: Retrospective cohort study; a review of complications. METHODS: Patients who underwent a single-level TLIF between January 2004 to May 2007 with either autograft iliac crest or rhBMP-2 were identified. A retrospective review of these patients included operative reports, pre- and postoperative medical records, most recent postoperative dynamic and static lumbar radiographs, and computed tomography scans (when available). RESULTS: A total of 130 patients met the study criteria; 119 patients were available for follow-up, with an average radiographic follow-up of 19.1 months and an average clinical follow-up of 27.6 months. Thirty-three patients received iliac crest autograft and 86 patients received rhBMP-2. Complications occurred in 40 of the 119 study patients (33.6%). The autograft group had a higher complication rate (45.5% vs. 29.1%), but the difference was not statistically significant (p=.09). Complications in the autograft group included persistent donor-site pain (30.3%), donor-site infection (3.1%), lumbar wound infection (6.1%), and postoperative radiculitis (3.0%). Complications in the rhBMP-2 group included postoperative radiculitis (14.0%), vertebral osteolysis (5.8%), ectopic bone formation (2.3%), and lumbar wound infection (3.5%). A hydrogel sealant (Duraseal; Confluent Surgical Inc., Waltham, MA, USA) was used in 37 out of 86 patients in the rhBMP-2 group. The use of this sealant decreased the rate of postoperative radiculitis in the rhBMP-2 group from 20.4% to 5.4% (p=.047). The radiographic nonunion rate at most recent follow-up was 3.0% in the autograft group and 3.5% (p=.90) in the rhBMP-2 group. CONCLUSIONS: The most common complications in the autograft group were related to the donor site. The most common complication in the rhBMP-2 group was postoperative radiculitis, the incidence of which is reduced by the use of a hydrogel sealant.

The use of RhBMP-2 in single-level transforaminal lumbar interbody fusion: a clinical and radiographic analysis.

The "off label" use of rhBMP-2 in the transforaminal lumbar interbody fusion (TLIF) procedure has become increasingly popular. Although several studies have demonstrated the successful use of rhBMP-2 for this indication, uncertainties remain regarding its safety and efficacy. The purpose of this study is to evaluate the clinical and radiographic outcomes of the single-level TLIF procedure using rhBMP-2. Patients who underwent a single-level TLIF between January 2004 and May 2006 with rhBMP-2 were identified. A retrospective evaluation of these patients included operative report(s), pre- and postoperative medical records, and dynamic and static lumbar radiographs. Patient-reported clinical outcome measures were obtained from a telephone questionnaire and included a modification of the Odom's criteria, a patient satisfaction score, and back and leg pain numeric rating scale scores. Forty-eight patients met the study criteria and were available for follow-up (avg. radiographic and clinical follow-up of 19.4 and 27.4 months, respectively). Radiographic fusion was achieved in 95.8% of patients. Good to excellent results were achieved in 71% of patients. On most recent clinical follow-up, 83% of patients reported improvement in their symptoms and 84% reported satisfaction with their surgery. Twenty-nine patients (60.4%) reported that they still had some back pain, with an average back pain numeric rating score of 2.8. Twenty patients (41.7%) reported that they still had some leg pain, with an average leg pain numeric rating score was 2.4. Thirteen patients (27.1%) had one or more complications, including transient postoperative radiculitis (8/48), vertebral osteolysis (3/48), nonunion (2/48), and symptomatic ectopic bone formation (1/48). The use of rhBMP-2 in the TLIF procedure produces a high rate of fusion, symptomatic improvement and patient satisfaction. Although its use eliminates the risk of harvesting autograft, rhBMP-2 is associated with other complications that raise concern, including a high rate of postoperative radiculitis.