Hiroyuki Yoshihara

National trends in the surgical treatment for lumbar degenerative disc disease: United States, 2000 to 2009

BACKGROUND CONTEXT Surgical treatment for lumbar degenerative disc disease (DDD) remains controversial. Options include anterior lumbar interbody fusion, posterior approach fusion procedures such as posterior lumbar interbody fusion (PLIF) and posterolateral lumbar fusion (PLF), anterior and posterior lumbar fusion (APLF), and total disc replacement (TDR). However, the trends during the last decade are uncertain. PURPOSE To examine the trends in the surgical treatment for lumbar DDD on a national level. STUDY DESIGN A retrospective analysis of population-based national hospital discharge data collected for the Nationwide Inpatient Sample (NIS). PATIENT SAMPLE In the NIS from 2000 to 2009, patients aged 18 years or older with primary diagnosis of lumbar/lumbosacral DDD who underwent surgical treatment were included. OUTCOME MEASURES Trends in the surgical treatment for lumbar DDD. METHODS Clinical data were derived from the NIS between 2000 and 2009. Patients aged 18 years or older with a primary diagnosis of lumbar/lumbosacral DDD who underwent spinal fusion or TDR were identified. Data regarding patient- and health care system-related characteristics were retrieved and analyzed. RESULTS A total of 380,305 patients underwent surgical treatment for lumbar DDD between 2000 and 2009. Population adjusted incidence increased 2.4-fold from 2000 to 2009. Among the procedures, APLF increased 3.0-fold and PLIF/PLF increased 2.8-fold. Total disc replacement did not increase significantly. Anterior lumbar interbody fusion was performed in 16.8% of patients, PLIF/PLF in 67.9%, APLF in 13.6%, and TDR in 1.8%. Surgical treatment for lumbar DDD was 1.8 times more common in the Midwest region and 1.7 times more common in the South region than in the Northeast region. Total disc replacement was more common in younger patients and in the Northeast region. Poterior lumbar interbody fusion/PLF was more common in older patients and in the South region. CONCLUSIONS During the last decade, surgical treatment for lumbar DDD has increased 2.4-fold in the United States. Although all fusion procedures significantly increased, TDR did not increase. Surgical treatment for lumbar DDD was more common in the Midwest and South regions. Trends in the procedures were different depending on the age group and hospital region.

Delay in Hip Fracture Surgery: An Analysis of Patient-Specific and Hospital-Specific Risk Factors.

Objectives: To empirically define a “delay” for hip fracture surgery based on clinical outcomes, and to identify patient demographics and hospital factors contributing to surgical delay. Design: Retrospective database analysis. Setting: Hospital discharge data. Patients/Participants: A total of 2,121,215 patients undergoing surgical repair of hip fracture in the National Inpatient Sample between 2000 and 2009. Intervention: Internal fixation or partial/total hip replacement. Main Outcome Measurements: Logistic regressions were performed to assess the effect of surgical timing on in-hospital complication and mortality rates, controlling for patient characteristics and hospital attributes. Subsequent regressions were performed to analyze which patient characteristics (age, gender, race, comorbidity burden, insurance status, and day of admission) and hospital factors (size, teaching status, and region) independently contributed to the likelihood of surgical delay. Results: Compared to same-day surgery, each additional day of delay was associated with a significantly higher overall complication rate. However, next-day surgery was not associated with an increased risk of in-hospital mortality. Surgery 2 calendar days (odds ratio: 1.13) and 3+ days (odds ratio: 1.33) after admission was associated with higher mortality rates. Based on these findings, “delay” was defined as surgery performed 2 or more days after admission. Significant factors related to surgical delay included comorbidity score, race, insurance status, hospital region, and day of admission. Conclusions: Surgical delay in hip fracture care contributes to patient morbidity and mortality. A variety of patient and hospital characteristics seem to contribute to surgical delay and point to important health care disparities. Level of Evidence: Prognostic Level II. See Instructions for Authors for a complete description of levels of evidence.

National trends in the utilization of blood transfusions in total hip and knee arthroplasty.

Total hip arthroplasty (THA) and total knee arthroplasty (TKA) are among the most common surgical procedures that necessitate blood transfusion. The purpose of this study was to examine the trends in the utilization of blood transfusions in THA and TKA in the US from 2000 to 2009 by analyzing the Nationwide Inpatient Sample (NIS). During the last decade, the allogeneic blood transfusion (ALBT) rate increased (THA: 11.2% to 19.1%, TKA: 7.7% to 12.4%), whereas the predonated autologous blood transfusion (PR-ABT) rate decreased (THA: 7.7% to 3.9%, TKA: 6.1% to 2.4%) in primary unilateral THA and TKA patients in US hospitals. Overall blood transfusion rates remained stable over time in primary unilateral THA and TKA patients.

Sacroiliac joint pain after lumbar/lumbosacral fusion: current knowledge

Recently, the sacroiliac joint (SIJ) has gained increased attention as a source of persistent or new pain after lumbar/lumbosacral fusion. The underlying pathophysiology of SIJ pain may be increased mechanical load, iliac crest bone grafting, or a misdiagnosis of SIJ syndrome. Imaging studies show more frequent degeneration of the SIJ in patients with lumbar/lumbosacral fusion than in patients without such fusion. Using injection tests, it has been shown that SIJ pain is the cause of persistent symptoms in a considerable number of patients after fusion surgery. Recent articles reporting on surgical outcomes of SIJ fusion include a high percentage of patients who had lumbar/lumbosacral fusion or surgery before, although well-controlled clinical studies are necessary to assess the efficacy of surgical treatment. Taking these findings into consideration, the possibility that the SIJ is the source of pain should be considered in patients with failed back surgery syndrome after lumbar/lumbosacral fusion.

National trends in spinal fusion for pediatric patients with idiopathic scoliosis: demographics, blood transfusions, and in-hospital outcomes.

Study Design. Analysis of population-based national hospital discharge data collected for the Nationwide Inpatient Sample database. Objective. To analyze trends in spinal fusion for pediatric patients with idiopathic scoliosis on a national level with regard to demographics, blood transfusions, and in-hospital outcomes. Summary of Background Data. Spinal fusion for pediatric patients with idiopathic scoliosis is required for rapid curve progression. For such patients and their families, blood transfusions and complications are important aspects of the surgery. Methods. The Nationwide Inpatient Sample database was used to identify pediatric patients with idiopathic scoliosis who underwent spinal fusion from 2000 to 2009 using the International Classification of Diseases, Ninth Revision, Clinical Modification codes. Demographics of the patients were retrieved. Trends in demographics, blood transfusion methods, and in-hospital outcomes were analyzed. Results. The total number of patients included in this study was 43,983. A total of 30.4% of patients received a blood transfusion. Predonated autologous blood transfusions decreased over time, whereas perioperative autologous blood transfusions increased over time (P < 0.05, respectively). The in-hospital overall complication rate was 14.4%. The respiratory complication rate was the highest among complications; however, the rate decreased over time (P = 0.003). In-hospital blood transfusion, complication, and mortality rates were high in certain subgroups of patients, such as those with increased Elixhauser Comorbidity Score and those who underwent anterior and posterior fusion. The mean length of hospital stay decreased over time (P = 0.043). Conclusion. During the last decade, 30% of pediatric patients with idiopathic scoliosis who underwent spinal fusion received some type of blood transfusion; and strategies for blood transfusion methods have changed over the years. A decreasing trend in the respiratory complication rate and reduction in length of hospital stay may indicate better postoperative care. Level of Evidence: 3

Predictors of Allogeneic Blood Transfusion in Total Hip and Knee Arthroplasty in the United States, 2000–2009

We examined the predictors of allogeneic blood transfusion (ALBT) in primary unilateral total hip arthroplasty (THA) and total knee arthroplasty (TKA), analyzing the Nationwide Inpatient Sample between 2000 and 2009. Multivariate logistic regression analysis was performed. Significant predictors of ALBT in both THA and TKA included older age, female gender, race, weight loss, anemia, Elixhauser Comorbidity Score, hospital caseload, hospital region, and insurance status. No autologous-related blood transfusion was a significant predictor of ALBT in THA, however, not in TKA. We believe that the utilization of ALBT in THA and TKA can decrease by taking these factors into consideration for patient blood management before surgery.

Trends in the utilization of blood transfusions in spinal fusion in the United States from 2000 to 2009.

Study Design. Retrospective study. Objective. The purpose of this study was to examine the trends in the utilization of blood transfusions in spinal fusion in the United States from 2000 to 2009. Summary of Background Data. Spinal fusion is among the most common surgical procedures that necessitate blood transfusion. Blood transfusion methods include predonated autologous blood transfusion (PR-ABT), perioperative autologous blood transfusion (PE-ABT) (intraoperative and postoperative blood collection), and allogeneic blood transfusion (ALBT). The trends in the utilization of these blood transfusion methods in spinal fusion during the past decade are uncertain. Methods. The Nationwide Inpatient Sample was used to identify patients who underwent spinal fusion from 2000 to 2009, using the International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) codes. Patients who received PR-ABT, PE-ABT, and ALBT were identified using the appropriate ICD-9-CM codes. Patient demographics, surgical variables, and hospital characteristics data were retrieved. Trends in the utilization of blood transfusions were analyzed. Results. From 2000 to 2009, there was an increasing trend in the ALBT rate (4.3%–8.0%, P < 0.001) and a decreasing trend in the PR-ABT rate (2.6%–0.7%, P < 0.001) in patients who underwent spinal fusion. The overall blood transfusion and PE-ABT rates remained stable. The ALBT rate was high in the subgroups of patients, such as pediatric and elderly patients, female patients, patients with increased Elixhauser Comorbidity Score, Medicare patients, and patients who underwent thoracolumbar, posterior, and anterior and posterior fusion. Conclusion. During the past decade, the ALBT rate increased, whereas the PR-ABT rate decreased in patients who underwent spinal fusion in US hospitals. The overall blood transfusion rate remained stable; however, it may be reduced by using a patient blood management program, targeting the subgroups of patients with the high ALBT rate. Level of Evidence: 3

Rods in spinal surgery: a review of the literature

BACKGROUND CONTEXT Spinal instrumentation has been used for more than five decades. Since the introduction of the Harrington rod in 1962, new rod materials and concepts have been developed. Rigid rod fixation has achieved higher fusion rates than previous methods. Recently, semirigid rod fixation devices have been used for both dynamic stabilization and fusion fixation. Memory rods, which have an interesting ability to return to their pre-bent shape when the temperature increases, are expected to be used for scoliosis correction. PURPOSE To review the previous literature regarding biofunctionality and biocompatibility of rods in spinal surgery. CONCLUSION The properties of each type of rod need to be taken into consideration when performing spinal instrumentation surgery.

Predictors of allogeneic blood transfusion in spinal fusion in the United States, 2004-2009.

Study Design. Retrospective study. Objective. To examine the predictors of allogeneic blood transfusion (ALBT) in spinal fusion. Summary of the Background Data. Spinal fusion is among the most common surgical procedures that necessitate blood transfusion. Methods. Using the appropriate International Classification of Diseases, 9th revision, Clinical Modification (ICD-9-CM) codes, patients who underwent spinal fusion from 2004 to 2009 were identified in the Nationwide Inpatient Sample database. These patients were then divided into groups of those who received ALBT and those who did not, using the appropriate ICD-9-CM code. Patient demographics, surgical variables, and hospital characteristics were also retrieved. Multivariate logistic regression analysis was performed to identify the predictors of ALBT in spinal fusion. Results. Significant predictors of ALBT in spinal fusion included age, female sex, race status, weight loss, anemia, Elixhauser Comorbidity Score, autologous-related blood transfusion, surgical level, surgical approach, revision surgery, number of fused vertebrae, and insurance status. Pediatric and elderly patients were more likely to receive ALBT than middle-aged patients. African American and Hispanic patients were more likely to receive ALBT than Caucasian patients. As the Elixhauser Comorbidity Score increased, the odds ratio increased (score ≥4; odds ratio, 3.07). Thoracolumbar fusion was the strongest predictor among surgery-related variables (odds ratio, 8.56). Private insurance patients were less likely to receive ALBT than Medicare patients. Conclusion. This study identified significant predictors of ALBT in spinal fusion. These factors need to be taken into consideration when developing a patient blood management strategy before surgery. In this study, autologous-related blood transfusion could not avoid ALBT; on the contrary, it was a significant predictor. Level of Evidence: 3

Trends in the surgical treatment for spinal metastasis and the in-hospital patient outcomes in the United States from 2000 to 2009

BACKGROUND CONTEXT Surgical treatment for spinal metastasis is still controversial. However, with the improvements in treatment for primary tumors, the survival rate of patients with spinal metastasis is enhanced. At the same time, surgical technique for spinal metastasis has also improved. PURPOSE The purpose of this study was to examine trends in the surgical treatment for spinal metastasis and in-hospital patient outcomes on a national level. STUDY DESIGN/SETTING This was an epidemiologic study using national administrative data from the Nationwide Inpatient Sample (NIS) database. PATIENT SAMPLE All discharges in the NIS with a diagnosis code of secondary malignant neoplasm of the spinal cord/brain, meninges, or bone who also underwent spinal surgery from 2000 to 2009 were included. OUTCOME MEASURES Trends in the surgical treatment for spinal metastasis, in-hospital complications and mortality, and resource use were analyzed. METHODS The NIS was used to identify patients who underwent surgical treatment for spinal metastasis from 2000 to 2009, using the International Classification of Diseases, Ninth revision, Clinical Modification codes. Trends in the surgical treatment for spinal metastasis and in-hospital patient outcomes were analyzed. RESULTS From 2000 to 2009, there was an increasing trend in the population growth-adjusted rate of surgical treatment for spinal metastasis (1.15-1.77 per 100,000; p<.001). Average Elixhauser comorbidity score increased over time (2.6-3.8; p<.001), and the overall in-hospital complication rate increased over time (14.8%-27.7%; p<.001), whereas in-hospital mortality rate and length of hospital stay remained stable over time (5.2%-4.6%, p=.413; 10.6-10.8 days, p=.626). Inflation-adjusted mean hospital charges increased more than two-fold over time (