Jonathan N Grauer

Yale-New Haven Hospital, New Haven, Connecticut, United States

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Publications (152)265.37 Total impact

  • Jonathan N Grauer, Andrea Halim, Kristaps J Keggi
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    ABSTRACT: Total hip arthroplasty (THA) and revision total hip arthroplasty are among the most commonly performed orthopedic procedures. There are many reported complications of THA, but intrapelvic complications are a rare subset. Bladder injuries have infrequently been described in association with this common procedure. We present an unusual case of a bladder tear occurring intraoperatively during a revision THA. It is suspected that the patient's history of multiple prior hip procedures caused adhesions of the bladder to the pelvic floor and predisposed the bladder to injury during acetabular revision. Previous reports of bladder injury relating to THA have described thermal necrosis, component migration, and occasional direct perforation. There are no prior case reports describing bladder tears related to adhesions occurring intraoperatively during revision THA. This case report highlights the importance of surgeon awareness of an unusual complication. In this case, intraoperative and postoperative recognition of a hematuria diagnosis led to the appropriate treatment, and this patient had an acceptable outcome.
    American journal of orthopedics (Belle Mead, N.J.) 08/2014; 43(8):E185-E188.
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    ABSTRACT: Study Design. Retrospective cohort.Objective. To determine the effect of non-insulin-dependent diabetes mellitus (NIDDM) and insulin-dependent diabetes mellitus (IDDM) on postoperative complications following elective lumbar fusion surgery.Summary of Background Data. Diabetes mellitus (DM) is a common chronic disease. The effects of NIDDM and IDDM on rates of postoperative complications, extended length of stay, and readmission after lumbar fusion surgery are not well established.Methods. A retrospective cohort study was conducted using the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database. Patients undergoing lumbar fusion between 2005 and 2012 were identified and characterized as having NIDDM, IDDM, or neither. Bivariate and multivariate analyses were used to test NIDDM and IDDM patients for increased risk of adverse postoperative outcomes over the initial 30 postoperative days.Results. 15,480 patients who underwent lumbar fusion were identified (13,043 were non-DM patients, 1,650 patients had NIDDM, and 787 patients had IDDM).NIDDM was independently associated with an increased risk of wound dehiscence (Relative Risk = 2.3; p = 0.033) and extended length of stay (1.2; p < 0.003).IDDM was independently associated with an increased risk of death (2.7; p = 0.020), sepsis (2.2; p = 0.002), septic shock (3.3; p = 0.032), unplanned intubation (2.8; p = 0.003), ventilator-assisted respiration > 48 hours postoperatively (2.8; p = 0.005), wound-related infection (1.9; p = 0.001), urinary tract infection (1.6, p = 0.011), pneumonia (3.1; p < 0.001), extended length of stay (1.5; p < 0.001), and readmission within 30 days (1.5, p = 0.036).Conclusions. Compared to non-DM patients, IDDM was associated with an increased risk of a considerably higher number of postoperative complications than NIDDM. These complications were also of greater severity. This important designation may improve preoperative risk stratification and counseling of diabetic patients prior to lumbar fusion surgery.
    Spine 07/2014; · 2.16 Impact Factor
  • Andrea Halim, Jonathan Grauer
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    ABSTRACT: We report a case of a C7 pars fracture subadjacent to C7 pedicle screw instrumentation at the caudal end of posterior cervical instrumentation construct. To date, posterior cervical instrumentation has been "off label"; however, the US Food and Drug Administration is considering approving label indication of such instrumentation for this common surgical practice. Complications related to the techniques are reported to be relatively low. We know of no previous reports of pars fractures occurring subadjacent to such instrumentation. A 43-year-old man underwent posterior C5-C7 instrumented fusion. Postoperatively, the patient experienced cervical spine injury after a mechanical fall down stairs. Work-up detected bilateral C7 pars fractures subadjacent to the posterior instrumentation construct. After we treated the pars fracture with distal extension of the posterior fusion to the level of T2, the patient progressed to union and marked improvement of initial clinical symptoms that was maintained 2.5 years after posterior instrumentation. To our knowledge, a C7 pars fracture subadjacent to posterior cervical instrumentation construct has not been reported. We hypothesize that the pars may have been vulnerable to fracture because of excessive bone resection during foraminotomy or decortication. This complication was successfully treated by extending the fusion caudally.
    American journal of orthopedics (Belle Mead, N.J.) 07/2014; 43(7):E137-E139.
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    ABSTRACT: : Study Design. Retrospective cohort study of 13,927 patients, 820 of whom received iliac crest bone graft (ICBG).Objective. To compare adverse events, length of stay (LOS), and readmission for patients receiving ICBG to those who did not using multivariate analysis to control for potentially confounding factors.Summary of Background Data. The use of ICBG in spinal fusion has been associated with increased surgical time, LOS, and donor site morbidity. Development of expensive bone graft substitutes has been predicated on these issues. Data on the effect of bone graft harvest on LOS and readmission rate is sparse, and multivariate analysis has not been used to control for confounding factors.Methods. Prospectively collected data from the American College of Surgeons National Surgical Quality Improvement Project (ACS NSQIP) 2010-2012 database was retrospectively reviewed. This includes demographics, comorbidities, surgical data, and hospital and 30-day follow-up outcomes data including adverse events, LOS, and readmission.Results. Only 5.9% of spinal fusions utilize ICBG.Bivariate logistic regression (used for categorical variables) found the ICBG cohort was more likely to have a postoperative blood transfusion (11.6% vs. 5.5%, p<0.001). Bivariate linear regression (used for continuous variables) found the ICBG cohort to have an extended operative time (+36.0 min, p<0.001) and extended LOS (+0.6 days, p<0.001).Multivariate analyses controlling for comorbidities, demographics, and approach determined postoperative blood transfusion (OR 1.5), extended operative time (+ 22.0 min, p<0.001) and LOS (+0.2 days, p = 0.037) to be significantly associated with ICBG use.No other adverse event was significantly associated with ICBG use. Readmission rates were not significantly different.Conclusion. This study used a large national database cohort and identified increased postoperative blood transfusion, extended operative time, and increased LOS as short-term outcomes associated with ICBG on multivariate analysis. Other short-term morbidities were not significantly associated with ICBG. Readmission rates were not affected.
    Spine 06/2014; · 2.16 Impact Factor
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    ABSTRACT: After lower extremity fracture or surgery, physicians often prescribe limited weight bearing. The current study was performed to evaluate teaching and compliance of touch-down weight bearing (defined as 25 lb) at a level I academic trauma center. A survey was distributed to physical therapists (PTs) from the orthopedic ward to gauge their training methods and their confidence in patients' ability to comply. Patients with recommended touch-down weight bearing were then evaluated on the day of discharge and again at their first follow-up appointment using the SmartStep weight-bearing measurement device (Andante Medical Devices, Inc, White Plains, New York). Fifteen PTs completed the survey (average of 14 years in practice). Inconsistency was observed in weight-bearing teaching methods: verbal cues were used 87% of the time, tactile methods were used 41%, demonstration was used 23%, and a scale was used only 1%. Limited confidence was found in the instruction efficacy by those surveyed. Twenty-one patients were seen the day of discharge and 18 of those were seen at first follow-up. At discharge, average minimum and maximum weight bearing were 3.2 and 30.2 lb, respectively. Only 31% of steps were within an acceptable range of 15 to 35 lb. At first follow-up, average minimum and maximum weight bearing were 12.2 and 50.8 lb, respectively. Only 27% of steps were within the acceptable range. The majority of steps were less than the prescribed weight at discharge, whereas the majority of steps were greater than the prescribed weight at first follow-up. These data suggest that more uniform and effective teaching methods for prescribed weight-bearing orders are warranted assuming compliance is an important clinical objective.
    Orthopedics 06/2014; 37(6):e552-6. · 1.05 Impact Factor
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    ABSTRACT: The use of national inpatient databases for spine surgery research has been increasing. Unfortunately, without firsthand knowledge of each specific database, it can be difficult to judge the validity of such studies. Large databases that rely on administrative data, such as International Classification of Diseases, Ninth Revision (ICD-9) codes, may misrepresent patient information and could thus affect the results of studies that use this data. The present study uses obesity, an easily quantified and objective variable, as an example comorbidity to assess the accuracy of ICD-9 codes in the setting of their continued use in spine database studies. A cross-sectional study at a large academic medical center. All patients spending at least one night in the hospital as an inpatient between April 1, 2013 and April 16, 2013. Obstetrics and gynecology, psychiatry, and pediatric patients were excluded. Proportion of patients for whom ICD-9 obesity diagnosis codes assigned at hospital discharge match chart-documented BMI. The medical record was reviewed for each patient, and obesity ICD-9 codes were directly compared to documented body mass index (BMI). No known conflicts of interest exist for this study. The study included 2,075 patients. Of 573 "obese" patients (calculated BMI 30-39.9), only 109 received the correct code (278.00), giving this ICD-9 code a sensitivity of 0.19. Of 174 "morbidly obese" patients (calculated BMI > 40), only 84 received the correct code (278.01), giving this ICD-9 code a sensitivity of 0.48. Using obesity as an example, this study highlights the potential errors inherent to using ICD-9-coded databases for spine surgery research. Should a study based on such data use "obesity" as a variable in any analyses, the reader should interpret these results with caution. We further suggest that obesity is likely not the only comorbidity to which these results apply. As database research continues to represent an increasing proportion of publications in the field of spine surgery, it is important to realize that study outcomes can be skewed by data accuracy, and thus should not be blindly accepted simply by virtue of large sample sizes.
    The spine journal: official journal of the North American Spine Society 04/2014; · 2.90 Impact Factor
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    ABSTRACT: : Study Design. Retrospective cohort study of 183 patients who underwent elective anterior cervical discectomy and fusion (ACDF) at a single institution over a two-year period.Objective. To determine which preoperative factors were independently associated with a prolonged hospital length of stay (LOS) following ACDF.Summary of Background Data. ACDF has become the most common treatment modality for addressing cervical spine pathology. Extended LOS following ACDF is associated with increased costs and complications. There is a lack of conclusive data for factors affecting LOS after ACDF. This study aims to create a multivariate model to determine the association of various patient and operative characteristics with LOS after ACDF.Methods. Patients who underwent elective ACDF at a single academic institution between January 2011 and February 2013 were identified using billing records. Their charts were reviewed to collect variables available preoperatively such as patient demographics, comorbidities, and surgery planned. Patients were categorized as normal or extended LOS, with extended LOS defined as LOS > 75th percentile. A multivariate logistic regression was used to determine which factors were independently associated with extended LOS.Results. A total of 183 ACDF patients were identified. The average LOS for this cohort was 2.0 ± 2.5 days (Mean ± Standard Deviation). Extended LOS was defined as ≥ 3 days. Multivariate analysis revealed that preoperative factors independently associated with extended LOS were history of non-spinal malignancy (Odds Ratio [OR] = 4.9), history of pulmonary disease (OR = 4.0), and procedures that included corpectomy (OR = 4.5).Conclusion. Patients with a history of non-spinal malignancy or pulmonary disease, as well as patients who underwent corpectomy, were more likely to have an extended LOS (ORs 4.0-4.9). Of significant note, other factors that one might expect to be associated with extended LOS did not independently predict extended LOS in this analysis.
    Spine 04/2014; · 2.16 Impact Factor
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    ABSTRACT: Retrospective cohort. To determine whether a genetic test is associated with successful Providence bracing for adolescent idiopathic scoliosis. Genetic factors have been defined that predict risk of progression of adolescent idiopathic scoliosis in a polygenic fashion. From these data, a commercially available genetic test, ScoliScore, was developed. It is now used in clinical practice for counseling and to guide clinical management. Bracing is a mainstay of treatment for adolescent idiopathic scoliosis. Large efforts have been made recently to reduce potential confounding across studies of different braces; however, none of these have considered genetics as a potential confounder. In particular, ScoliScore has not been evaluated in a population undergoing bracing. We conducted a retrospective cohort study in which we identified a population of adolescent idiopathic scoliosis patients who were initiated with Providence bracing and followed over time. While these patients did not necessarily fit the commercial indications for ScoliScore, we contacted the patients and obtained a saliva sample from each for genetic analysis. We then tested whether ScoliScore correlated with the outcome of their bracing therapy. We were able to contact and invite 25 eligible subjects, of whom 16 (64.0%) returned samples for laboratory analysis. Patients were followed for an average of 2.3 years (range 1.1 to 4) after initiation of the Providence brace. 8 patients (50.0%) progressed to more than 45 degrees, while 8 patients (50.0%) did not. The mean ScoliScore among those who progressed to more than 45 degrees was higher than that among those who did not (176 vs. 112, P=0.030). We demonstrate that a genetic test correlates with bracing outcome. It may be appropriate for future bracing studies to include analysis of genetic predisposition to limit potential confounding.
    Journal of spinal disorders & techniques 03/2014; · 1.21 Impact Factor
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    ABSTRACT: National databases are being used with increasing frequency to conduct orthopaedic research. However, there are important differences in these databases, which could result in different answers to similar questions; this important potential limitation pertaining to database research in orthopaedic surgery has not been adequately explored. The purpose of this study was to explore the interdatabase reliability of two commonly used national databases, the Nationwide Inpatient Sample (NIS) and the National Surgical Quality Improvement Program (NSQIP), in terms of (1) demographics; (2) comorbidities; and (3) adverse events. In addition, using the NSQIP database, we identified (4) adverse events that had a higher prevalence after rather than before discharge, which has important implications for interpretation of studies conducted in the NIS. A retrospective cohort study of patients undergoing operative stabilization of transcervical and intertrochanteric hip fractures during 2009 to 2011 was performed in the NIS and NSQIP. Totals of 122,712 and 5021 patients were included from the NIS and NSQIP, respectively. Age, sex, fracture type, and lengths of stay were compared. Comorbidities common to both databases were compared in terms of more or less than twofold difference between the two databases. Similar comparisons were made for adverse events. Finally, adverse events that had a greater postdischarge prevalence were identified from the NSQIP database. Tests for statistical difference were thought to be of little value given the large sample size and the resulting fact that statistical differences would have been identified even for small, clinically inconsequential differences resulting from the associated high power. Because it is of greater clinical importance to focus on the magnitude of differences, the databases were compared by absolute differences. Demographics and hospital lengths of stay were not different between the two databases. In terms of comorbidities, the prevalences of nonmorbid obesity, coagulopathy, and anemia in found in the NSQIP were more than twice those in the NIS; the prevalence of peripheral vascular disease in the NIS was more than twice that in the NSQIP. Four other comorbidities had prevalences that were not different between the two databases. In terms of inpatient adverse events, the frequencies of acute kidney injury and urinary tract infection in the NIS were more than twice those in the NSQIP. Ten other inpatient adverse events had frequencies that were not different between the two databases. Because it does not collect data after patient discharge, it can be implied from the NSQIP data that the NIS does not capture more than ½ of the deaths and surgical site infections occurring during the first 30 postoperative days. This study shows that two databases commonly used in orthopaedic research can identify similar populations of operative patients but may generate very different results for specific commonly studied comorbidities and adverse events. The NSQIP identified higher rates of morbid obesity, coagulopathy, and anemia. The NIS identified higher rates of peripheral vascular disease, acute kidney injury, and urinary tract infection. Level II, prognostic study. See the Instructions for Authors for a complete description of levels of evidence.
    Clinical Orthopaedics and Related Research 03/2014; · 2.79 Impact Factor
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    ABSTRACT: Retrospective review of the prospective American College of Surgeons National Surgical Quality Improvement Project (ACS NSQIP) database with 30-day follow-up of 2164 patients undergoing elective anterior cervical discectomy and fusion (ACDF). To determine factors independently associated with increased length of stay (LOS) and complications following ACDF in order to facilitate preoperative planning and setting of realistic expectations for patients and providers. The effect of individual preoperative factors on LOS and complications has been evaluated in small-scale studies. Large database analysis with multivariate analysis of these variables has not been reported. The ACS NSQIP database from 2005-2010 was queried for patients undergoing ACDF procedures. Pre and perioperative variables were collected. Multivariate regression determined significant predictors (P<0.05) of extended LOS and complications. Average LOS was 2.0±4.0 days (mean±SD) with a range of 0 to 103 days. By multivariate analysis, age≥65, functional status, transfer from facility, preoperative anemia, and diabetes were the preoperative factors predictive of extended LOS. Major complications, minor complications, and extended surgery time were the perioperative factors associated with increased LOS. The elongating effect of these variables was determined, and ranged from 0.5-5.0 days. 71 (3.3%) had a total of 92 major complications, including return to OR (40), venous thrombotic events (13), respiratory (21), cardiac (6), mortality (5), sepsis (4), and organ space infection (3). Multivariate analysis determined ASA score≥3, preoperative anemia, age≥65, extended surgery time and male gender to be predictive of major complications (odds ratios ranging between 1.756-2.609) No association found between levels fused and LOS or complications. Extended LOS following ACDF is associated with factors including age, anemia, and diabetes, as well as the development of postoperative complications. One in 33 patients develops a major complication post-operatively, which are associated with an increased LOS of 5 days.
    Journal of spinal disorders & techniques 02/2014; · 1.21 Impact Factor
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    ABSTRACT: Study Design. Retrospective cohort.Objective. To identify factors that were independently associated with increased postoperative length of stay (LOS) and readmission in patients who underwent elective laminectomy for lumbar spinal stenosis (LSS).Summary of Background Data. LSS is a common pathology that is traditionally treated with decompressive laminectomy. Risk factors associated with increased LOS and readmission have not been fully characterized for laminectomy.Methods. Patients who underwent laminectomy for LSS during 2011 and 2012 were identified from the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database. Patient characteristics were tested for association with LOS and readmission using bivariate and multivariate analyses. Patients with LOS > 10 days were excluded from the readmission analysis as the ACS-NSQIP only captures readmissions within 30 postoperative days, and the window for potential readmission was deemed too short for patients staying longer than 10 days.Results. A total of 2,358 laminectomy patients met inclusion criteria. The average age was 66.4 ± 11.7 years (mean ± standard deviation). Average postoperative LOS was 2.1 ± 2.6 days. Of those meeting criteria for readmission analysis, 3.7% of patients (86 of 2,339) were readmitted within 30 days postoperatively.Independent risk factors for prolonged LOS were increased age (p < 0.001), increased body mass index (p = 0.004), American Society of Anesthesiologists class 3-4 (p = 0.005), and preoperative hematocrit < 36.0 (p = 0.001). Independent risk factors for readmission were increased age (p = 0.013), increased body mass index (p = 0.040), ASA class 3-4 (p < 0.001), and steroid use (p = 0.001). The most common reason for readmission was surgical site-related infections (25.0% of patients readmitted in 2012).Conclusion. The identified factors associated with LOS and readmission following lumbar laminectomy may be useful for optimizing patient care.
    Spine 02/2014; · 2.16 Impact Factor
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    ABSTRACT: The "July effect" is the hypothetical increase in morbidity thought to be associated with the training of new residents during the first portion of the academic year. We evaluated for the presence of the July effect in the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database among 21,434 patients who underwent primary total hip or knee arthroplasty. There was no association of an interaction term for academic quarter and resident involvement with "serious adverse events" (P=0.656) or "any adverse events" (P=0.578). As a result, this study could not demonstrate a July effect. Patients can be reassured that undergoing total joint arthroplasty during the first part of the academic year is without increased risk of adverse events related to the training of residents.
    The Journal of arthroplasty 02/2014; · 1.79 Impact Factor
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    ABSTRACT: Study Design. Retrospective cohort study.Objective. To identify factors that are independently associated with increased surgical drain output in patients who have undergone ACDF.Summary of Background Data. Surgical drains are typically placed following ACDF to reduce the risk of complications associated with neck hematoma. The orthopaedic literature has repeatedly challenged the use of surgical drains following many procedures, and there are currently no guidelines for determining which patients are most likely to benefit from drain placement after ACDF.Methods. Consecutive patients who underwent elective ACDF with surgical drain placement at a single academic institution between January 2011 and February 2013 were identified using billing records. Patient information was abstracted from the medical record. Patients were categorized based on normal or increased total drain output, with increased drain output defined as total drain output ≥ 50th percentile (30mL). A multivariate logistic regression was used to determine which factors were independently associated with increased drain output.Results. A total of 151 ACDF patients met inclusion criteria. Total drain output ranged from 0 mL to 265 mL. The average drain output for this cohort was 42.3 ± 45.5 mL (mean ± standard deviation). Among all patients in the study, 80 patients had increased drain output (drain output ≥ 50 percentile or 30 mL).Multivariate analysis identified three independent predictors of increased drain output: age ≥ 50 years (Odds Ratio [OR] = 3.9), number of levels (2 levels, OR = 2.7; 3-4 levels, OR = 17.0), and history of smoking (OR = 2.8). One patient developed a postoperative neck hematoma while a drain was in place.Conclusion. Patients with the above-identified factors associated with increased drain output may benefit most from surgical drain placement after ACDF. Nonetheless, neck hematoma is still possible even with drain use.
    Spine 01/2014; · 2.16 Impact Factor
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    ABSTRACT: Background Context The use of national inpatient databases for spine surgery research has been increasing. Unfortunately, without firsthand knowledge of each specific database, it can be difficult to judge the validity of such studies. Large databases that rely on administrative data, such as International Classification of Diseases, Ninth Revision (ICD-9) codes, may misrepresent patient information and could thus affect the results of studies that use this data. Purpose The present study uses obesity, an easily quantified and objective variable, as an example comorbidity to assess the accuracy of ICD-9 codes in the setting of their continued use in spine database studies. Study Design/Setting A cross-sectional study at a large academic medical center. Patient Sample All patients spending at least one night in the hospital as an inpatient between April 1, 2013 and April 16, 2013. Obstetrics and gynecology, psychiatry, and pediatric patients were excluded. Outcome Measures Proportion of patients for whom ICD-9 obesity diagnosis codes assigned at hospital discharge match chart-documented BMI. Methods The medical record was reviewed for each patient, and obesity ICD-9 codes were directly compared to documented body mass index (BMI). No known conflicts of interest exist for this study. Results The study included 2,075 patients. Of 573 “obese” patients (calculated BMI 30-39.9), only 109 received the correct code (278.00), giving this ICD-9 code a sensitivity of 0.19. Of 174 “morbidly obese” patients (calculated BMI > 40), only 84 received the correct code (278.01), giving this ICD-9 code a sensitivity of 0.48. Conclusions Using obesity as an example, this study highlights the potential errors inherent to using ICD-9-coded databases for spine surgery research. Should a study based on such data use “obesity” as a variable in any analyses, the reader should interpret these results with caution. We further suggest that obesity is likely not the only comorbidity to which these results apply. As database research continues to represent an increasing proportion of publications in the field of spine surgery, it is important to realize that study outcomes can be skewed by data accuracy, and thus should not be blindly accepted simply by virtue of large sample sizes.
    The Spine Journal. 01/2014;
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    ABSTRACT: Background context Magnetic resonance imaging (MRI) is frequently used in the evaluation of degenerative conditions in the lumbar spine. The relative inter-rater and intra-rater agreements of MRI findings across different pathological conditions are underexplored, as most studies are focused on specific findings. Purpose To characterize the inter-rater and intra-rater agreement of MRI findings used to assess the degenerative lumbar spine. Study Design A retrospective diagnostic study at a large academic medical center was undertaken with a panel of orthopaedic surgeons and musculoskeletal radiologists to assess lumbar MRIs using standardized criteria. Patient Sample Seventy-five subjects who underwent routine lumbar spine MRI at our institution. Outcome Measures Each MRI study was assessed for ten lumbar degenerative findings using standardized criteria. Lumbar vertebral levels were assessed independently, where applicable, for a total of 52 data points collected per study. Methods T2-weighted axial and sagittal MRI sequences were presented in random order to the four reviewers (two orthopaedic spine surgeons and two musculoskeletal radiologists) independently to determine inter-rater agreement. The first ten studies were re-evaluated at the end to determine intra-rater agreement. Images were assessed using standardized and pilot-tested criteria to assess disc degeneration, stenosis, and other degenerative changes. Inter-rater and intra-rater absolute percent agreements were calculated. To highlight the most clinically important MRI disagreements, a modified agreement analysis was also performed (in which disagreements between the lowest two severity grades for applicable conditions were ignored). Fleiss' kappa coefficients for inter-rater agreement were determined. There were no sources of funding or conflicts of interest related to this study. Results The overall absolute and modified inter-rater agreements were 76.9% and 93.5%, respectively. The absolute and modified intra-rater agreements were 81.3% and 92.7%. Average Fleiss' kappa coefficient was 0.431, suggesting moderate overall agreement. However, when stratified by condition, absolute inter-rater agreement ranged from 65.1% to 92.0%. Disc hydration, disc space height, and bone marrow changes exhibited the lowest absolute inter-rater agreements. The absolute intra-rater agreement had a narrower range, from 74.5% to 91.5%. Fleiss' kappa coefficients ranged from fair to substantial agreement (0.282-0.618). Conclusions Even in a study using standardized evaluation criteria, there was significant variability in the inter-rater and intra-rater agreement of MRI in assessing different degenerative conditions of the lumbar spine. Clinicians should be aware of the condition-specific diagnostic limitations of MRI interpretation.
    The spine journal: official journal of the North American Spine Society 01/2014; · 2.90 Impact Factor
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    ABSTRACT: Study Design. Retrospective cohort.Objective. To evaluate for the presence and magnitude of the July effect within elective spine surgery.Summary of Background Data. The July effect is the hypothetical increase in morbidity and mortality thought to be associated with the influx of new (or newly promoted) trainees during the first portion of the academic year. Studies evaluating for the presence and magnitude of the July effect have demonstrated conflicting results.Methods. We accessed the American College of Surgeons National Surgical Quality Improvement Program database from years 2005-2010. Statistical analyses were conducted using bivariate and multivariate logistic regression.Results. A total of 14,986 cases met inclusion criteria and constitute the study population. Of these, 26.5% occurred in the first academic quarter and 25.3% had resident involvement. The rate of serious adverse events (SAEs) was 1.9 times higher and the rate of any adverse events (AAEs) was 1.6 times higher among cases with resident involvement than among cases without (p < 0.001 for both). Among cases without resident involvement, the rates of SAEs and AAEs did not differ by academic quarter. Similarly, among cases with resident involvement, the rates of SAEs and AAEs did not differ by academic quarter.Conclusion. We could not demonstrate that the training of new (or newly promoted) residents is associated with an increase in the adverse events of spine surgery. Safeguards that have been put in place to ensure patient safety during this training period appear to be effective. While adverse events were more common among cases with resident involvement than among cases without resident involvement, our data suggest that this association is more likely a product of the riskier population of cases in which residents participate than of the resident involvement itself.
    Spine 12/2013; · 2.16 Impact Factor
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    ABSTRACT: Study Design. Retrospective cohort study of the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database from 2005 to 2010 that included 1,861 patients who had undergone elective posterior lumbar fusion.Objective. To characterize factors that were independently associated with increased hospital length of stay (LOS) in patients who had undergone elective posterior lumbar fusion.Summary of Background Data. Posterior lumbar spine fusion is a common surgical procedure used to treat lumbar spine pathology. LOS is an important clinical variable and a major determinant of inpatient hospital costs. There is lack of studies in the literature using multivariate analysis to specifically examine the predictors of LOS after elective posterior lumbar fusion.Methods. Patients who underwent elective posterior lumbar fusion from 2005 to 2010 were identified in the ACS-NSQIP database. Preoperative and intraoperative variables were extracted for each case and a multivariate linear regression was performed to assess the contribution of each variable to LOS.Results. A total of 1,861 elective posterior lumbar fusion patients were identified. The average age for patients in this cohort was 60.6 ± 13.9 years (mean ± standard deviation [SD]) with a body mass index (BMI) of 30.3 ± 6.2 kg/m. 44.7% of patients were male. LOS ranged from 0 days to 51 days. Multivariate linear regression identified age (p < 0.001), morbid obesity (BMI ≥ 40 kg/m, p < 0.001), American Society of Anesthesiologists (ASA) class (p = 0.001), operative time (p < 0.001), multilevel procedure (p = 0.001), and intraoperative transfusion (p < 0.001) as significant predictors of extended LOS.Conclusion. The identified preoperative and intraoperative variables associated with extended LOS after elective posterior lumbar fusion may be helpful to clinicians for patient counseling and postoperative planning.
    Spine 12/2013; · 2.16 Impact Factor
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    ABSTRACT: Prior studies on the impact of obesity on spine surgery outcomes have focused mostly on lumbar fusions, do not examine lumbar discectomies or decompressions, and have shown mixed results regarding complications. Differences in sample sizes as well as differences in the BMI thresholds for the definition of the obese vs. comparison cohorts could account for the inconsistencies in the literature. To analyze whether different degrees of obesity influence the complication rates in patients undergoing lumbar spine surgery. Retrospective cohort analysis of prospectively collected data using the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database from 2005 to 2010. Patients in the de-identified, risk-adjusted, and multi-institutional ACS-NSQIP database undergoing lumbar anterior fusion, posterior fusion, TLIF/PLIF, discectomy, or decompression. Primary outcome measures were 30-day post-surgical complications, including PE, DVT, death, system-specific complications (wound, pulmonary, urinary, CNS, cardiac), septic complications and having ≥ 1 complication overall. Secondary outcomes were time spent in the operating room, blood transfusions, length of stay, and re-operation within 30 days. Patients undergoing lumbar anterior fusion, posterior fusion, TLIF/PLIF, discectomy, or decompression in the ACS-NSQIP, 2005-2010 were categorized into 4 BMI groups: non-obese (18.5-29.9 kg/m(2)), obese I (30-34.9 kg/m(2)), obese II (35-39.9 kg/m(2)), obese III (≥40 kg/m(2)). Obese I-III patients were compared to patients in the non-obese category using χ(2) and ANOVA. Multivariate linear/logistic regression models were used to adjust for preoperative risk factors. The authors report no sources of funding or conflicts of interest related to this study. Data was available for 10,387 patients undergoing lumbar surgery. Of these, 4.5% underwent anterior fusion, 17.9% posterior fusion, 6.3% TLIF/PLIF, 40.7% discectomy, 30.5% decompression. Among all patients, 25.6% were obese I, 11.5% obese II, and 6.9% obese III. On multivariate analysis, obese I and III had a significantly increased risk of urinary complications and obese II and III patients had a significantly increased risk of wound complications. Only obese III patients, however, had a statistically increased risk of having increased time spent in the operating room, an extended length of stay, pulmonary complications and of having ≥ 1 complication (all p < .05). Patients with high BMI appear to have higher complication rates after lumbar surgery than patients who are non-obese. However, the complication rates seem to increase substantially for obese III patients. These patients have longer times spent in the operating room, extended hospitals stays and an increased risk for wound, urinary, pulmonary complications and for having at least one or more complication overall. Surgeons should be aware of the increased risk of multiple complications for patients with BMI ≥ 40 kg/m(2).
    The spine journal: official journal of the North American Spine Society 12/2013; · 2.90 Impact Factor
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    ABSTRACT: Lumbar pathology is often associated with axial pain or neurologic complaints. It is often presumed that such pain is associated with decreased lumbar motion; however, this correlation is not well established. The utility of various outcome measures that are used in both research and clinical practice have been studied, but the connection with range of motion has not been well documented. The current study was performed to objectively assess the postulated correlation of lumbar complaints (based on standardized outcome measures) with extremes of lumbar range of motion (ROM) and functional range of motion with activities of daily living (fROM) as assessed with an electrogoniometer. Clinical cohort study. Subjects slated to undergo a lumbar intervention (injection, decompression, and/or fusion) were voluntarily enrolled in the study. Visual Analog Scale (VAS) for axial, lower extremity, and combined axial and lower extremity, as well as Oswestry-Disability Index (ODI). Pain and disability scores were assessed with VAS and ODI. A previously validated electrogoniometer was used to measure ROM (extremes of motion in three planes) and fROM (functional motion during 15 simulated activities of daily living). Pain and disability scores were analyzed for statistically significant association with the motion assessments using linear regression analyses. 28 males and 39 females were enrolled with an average age of 55.6 years (range 18-79). ODI and VAS were positively associated (p<0.001). Combined axial and lower extremity VAS was associated with lateral and rotational ROM (p<0.05), but not flexion/extension or any fROM. Similar findings were noted for separately analyzed axial and lower extremity VAS. On the other hand, ODI was inversely correlated with ROM in all planes and fROM in at least one plane for 10 of 15 ADLs (p<0.05). Extremes of lumbar motion and motions associated with activity of daily living are of growing clinical interest. Even though ODI and VAS are associated with each other, ODI appears to be a better predictor of these motion parameters than VAS (axial, lower extremity, or combined) and may be more useful in the clinical setting when considering functional movement parameters.
    The spine journal: official journal of the North American Spine Society 11/2013; · 2.90 Impact Factor
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    ABSTRACT: Vertebral body derived bone marrow aspirate (BMA, with an appropriate carrier) is a potential alternative to traditional iliac crest bone graft for use in spinal fusion surgery. No studies have looked at the effect of different temporary handling / storage conditions on the osteoprogenitor potential of BMA. This is especially important since aspirate, as with cancellous and/or cortical grafts, may be extracted some time prior to actual implementation in regular clinical use. In order to characterize factors that affect BMA cell concentration during routine spinal instrumentation, this study examines whether cell counts change significantly between the second pedicle aspirated and the first pedicle harvested at the same vertebral level. This study also aims to examine the optimal perioperative storage conditions for BMA obtained from the vertebral body. In vitro concentrations of viable cells were determined in BMA harvested from the first and second pedicles on every vertebral level, and after one hour of storage in different perioperative conditions. BMA was harvested from 28 pedicles from seven patients undergoing lumbar instrumented fusion surgeries. Viable nucleated cell concentrations in BMA. After obtaining HIC approval from our institution, twenty eight vertebral marrow aspirates (obtained from seven patients) were evaluated. Based on prior work, four ml aspirates from each pedicle were evaluated. BMA was aspirated from both pedicles of two vertebral levels per patient. Samples were divided and placed in different storage conditions to examine the effect of laterality (first versus second pedicle aspirated per level), temperature, media, and time, on nucleated cell counts. No funding was received for this study, and the authors disclose no study specific conflicts of interest. Cell count was not significantly different between the first or second side aspirated for each vertebral level. Similarly, no significant differences were found for samples after one hour of storage at different temperatures (0°C, room temperature, or 37°C) or media (none, saline, essential media). Of the conditions examined, time from aspiration was the only variable found to have an impact on nucleated cell counts (p=0.003). The viable cell count decreased to less than half by four hours. As vertebral BMA is increasingly considered as a bone grafting option, the field would be remiss not to consider factors that could affect cell viability after abstraction and prior to implementation. We expected a greater effect of perioperative storage conditions than was observed. Although the variables evaluated might show small effects on cell viability in a larger study, this would not be expected to be significant. In the current study, only prolonged time from abstraction could be shown to have a significant effect on cell viability.
    The spine journal: official journal of the North American Spine Society 10/2013; · 2.90 Impact Factor

Publication Stats

2k Citations
265.37 Total Impact Points

Institutions

  • 1997–2014
    • Yale-New Haven Hospital
      New Haven, Connecticut, United States
  • 1997–2013
    • Yale University
      • Department of Orthopaedics and Rehabilitation
      New Haven, CT, United States
  • 2011
    • University Center Rochester
      Rochester, Minnesota, United States
    • Brigham and Women's Hospital
      • Department of Medicine
      Boston, MA, United States
  • 2009
    • Kansas City VA Medical Center
      Kansas City, Missouri, United States
    • University of Rochester
      • Department of Orthopaedics and Rehabilitation
      Rochester, NY, United States
  • 2008
    • University of New Haven
      New Haven, Connecticut, United States
  • 2003–2007
    • Thomas Jefferson University
      • • Rothman Institute
      • • Department of Orthopaedic Surgery
      Philadelphia, Pennsylvania, United States
  • 2003–2005
    • Rothman Institute
      Philadelphia, Pennsylvania, United States