The impact of diabetes mellitus on patients undergoing degenerative cervical spine surgery

Insulin dependence negatively impacts outcomes in anterior cervical discectomy with fusions: a ten-year retrospective analysis

BACKGROUND CONTEXT

Although anterior cervical discectomy and fusion (ACDF) procedures for cervical spine disease have been increasing amid a growing diabetic patient population, there is a paucity of literature focusing on insulin-dependence as a risk-factor for post-operative ACDF complications.

PURPOSE

To evaluate the differential impact of insulin dependence on perioperative outcomes including total length of stay, surgical, and medical complications within thirty days following ACDF.

STUDY DESIGN/SETTING

A retrospective cohort, large multicenter database study.

PATIENT SAMPLE

The American College of Surgeons National Surgical Quality Improvement Program database was queried to retrospectively identify patients who had undergone ACDF between 2011 and 2021 using the Current Procedural Terminology code 22551.

OUTCOME MEASURES

Perioperative surgical and medical complications.

METHODS

The study population was divided into 3 groups 1) insulin-dependent diabetes mellitus (IDDM), 2) non-insulin-dependent diabetes mellitus (NIDDM), and 3) no diabetes mellitus (non-DM). One-way analysis of variance for continuous variables and chi-square tests for categorical variables were used to identify differences in perioperative variables between the 3 groups. Multivariable logistic regression analysis assessed the effect of diabetes mellitus status on post-operative medical and surgical outcomes.

RESULTS

A total of 85,758 ACDF procedures were identified between 2011 and 2021, of which 5,178 were IDDM, 9,652 were NIDDM, and 70,982 were non-DM. The rates of surgical and medical complication varied between the 3 groups. IDDM patients had the highest rates of at least one medical complication (6.1%). Only IDDM increased the risk for medical complications (OR: 1.320, 95% CI [1.144-1.518]) and extended hospital length of stay (LOS) (OR: 1.244, 95% CI [1.071-1.441]) following a multivariate logistic regression analysis.

CONCLUSION

Patients with IDDM were at an increased risk for postoperative medical complications and extended hospital LOS. Personalized postoperative management, guided by risk assessment is indicated for this population. These findings can be used to improve risk stratification and informed consent for DM patients who are insulin dependent.

The Influence of Preoperative Anticoagulant and Antiplatelet Therapy on Rebleeding Rates in Patients Suffering from Spinal Metastatic Cancer: A Retrospective Cohort Study

INTRODUCTION

The age of patients requiring surgery for spinal metastasis, primarily those over 65, has risen due to improved cancer treatments. Surgical intervention targets acute neurological deficits and instability. Anticoagulants are increasingly used, especially in the elderly, but pose challenges in managing bleeding complications. The study examines the correlation between preoperative anticoagulant/antiplatelet use and bleeding risks in spinal metastasis surgery, which is crucial for optimizing patient outcomes.

MATERIAL AND METHODS

In a retrospective study at our department from 2010 to 2023, spinal tumor surgery patients were analyzed. Data included demographics, neurological status, surgical procedure, preoperative anticoagulant/antiplatelet use, intra-/postoperative coagulation management, and the incidence of rebleeding. Coagulation management involved blood loss assessment, coagulation factor administration, and fluid balance monitoring post-surgery. Lab parameters were documented at admission, preop, postop, and discharge.

RESULTS

A cohort of 290 patients underwent surgical treatment for spinal metastases, predominantly males (63.8%, n = 185) with a median age of 65 years. Preoperatively, 24.1% (n = 70) were on oral anticoagulants or antiplatelet therapy. Within 30 days, a rebleeding rate of 4.5% (n = 9) occurred, unrelated to preoperative anticoagulation status (p > 0.05). A correlation was found between preoperative neurologic deficits (p = 0.004) and rebleeding risk and the number of levels treated surgically, with fewer levels associated with a higher incidence of postoperative bleeding (p < 0.01).

CONCLUSIONS

Surgical intervention for spinal metastatic cancer appears to be safe regardless of the patient's preoperative anticoagulation status. However, it remains imperative to customize preoperative planning and preparation for each patient, emphasizing meticulous risk-benefit analysis and optimizing perioperative care.

Postoperative Length of Stay in Patients With Stress Hyperglycemia Compared to Patients With Diabetic Hyperglycemia: A Retrospective Cohort Study

BACKGROUND

Postoperative hospital length of stay (LOS) is longer in patients with diabetes than in patients without diabetes. Stress hyperglycemia (SH) in patients without a history of diabetes has been associated with adverse postoperative outcomes. The effect of SH on postoperative LOS is uncertain. The aim of this study is to compare postoperative LOS in patients with SH to patients with diabetic hyperglycemia (DH) following noncardiac surgery.

METHODS

We carried out a retrospective cohort study of inpatients with at least two glucose measurements ≥180 mg/dL. Two groups were compared. Patients with SH had no preoperative history of diabetes. Patients were considered to have DH if they had an established preoperative diagnosis of diabetes mellitus or a preoperative hemoglobin A1c (HbA1c) ≥6.5%. The primary outcome measure was hospital LOS.

RESULTS

We included 270 patients with postoperative hyperglycemia-82 in the SH group and 188 in the DH group. In a linear regression analysis, hospital LOS was longer in the SH group than in the DH group (10.4 vs 7.3 days; P = .03). Within the SH group, we found no association between LOS and prompt treatment of hyperglycemia within 12 hours (P = .43), insulin dose per day (P = .89), or overall mean glucose (P = .13).

CONCLUSIONS

Postoperative LOS was even longer in patients with SH than in patients with DH, representing a potential target for quality improvement efforts. We did not, however, find evidence that improved treatment of SH was associated with reduction in LOS.

Diabetes in Orthopaedic Sports Medicine Surgeries Standard Review

Diabetes mellitus has been shown to affect the outcomes of various orthopaedic procedures. Although orthopaedic sports medicine procedures tend to be less invasive and are often performed on younger and healthier patients, diabetes is associated with an increased risk of postoperative infection, readmission, and lower functional outcome scores. However, this risk may be moderated by the glycemic control of the individual patient, and patients with a low perioperative hemoglobin A1c may not confer additional risk. Further research is needed to evaluate the impact of diabetes on surgical outcomes in sports orthopaedics is needed, with the goal of evaluating mediating factors such as glycemic control in mind.

Preoperative medical assessment for adult spinal deformity surgery: a state-of-the-art review

INTRODUCTION

The purpose of this study is to provide a state-of-the-art review regarding risk factors for perioperative complications in adult spinal deformity (ASD) surgery. The review includes levels of evidence for risk factors associated with complications in ASD surgery.

METHODS

Using the PubMed database, we searched for complications, risk factors, and adult spinal deformity. The included publications were assessed for level of evidence as described in clinical practice guidelines published by the North American Spine Society, with summary statements generated for each risk factor (Bono et al. in Spine J 9:1046-1051, 2009).

RESULTS

Frailty had good evidence (Grade A) as a risk for complications in ASD patients. Fair evidence (Grade B) was assigned for bone quality, smoking, hyperglycemia and diabetes, nutritional status, immunosuppression/steroid use, cardiovascular disease, pulmonary disease, and renal disease. Indeterminate evidence (Grade I) was assigned for pre-operative cognitive function, mental health, social support, and opioid utilization.

CONCLUSIONS

Identification of risk factors for perioperative complications in ASD surgery is a priority for empowering informed choices for patients and surgeons and managing patient expectations. Risk factors with grade A and B evidence should be identified prior to elective surgery and modified to reduce the risk of perioperative complications.

Common procedures and conditions leading to inpatient hospital admissions in adults with and without diabetes from 2015 to 2019 in Germany : A comparison of frequency, length of hospital stay and complications

OBJECTIVE

To evaluate common surgical procedures and admission causes in inpatient cases with diabetes in Germany between 2015 and 2019 and compare them to inpatient cases without diabetes.

METHODS

Based on the German diagnosis-related groups (G-DRG) statistics, regression models stratified by age groups and gender were used to calculate hospital admissions/100,000 individuals, hospital days as well as the proportion of complications and mortality in inpatient cases ≥ 40 years with or without a documented diagnosis of diabetes (type 1 or type 2).

RESULTS

A total of 14,222,326 (21%) of all inpatient cases aged ≥ 40 years had a diagnosis of diabetes. More middle-aged females with vs. without diabetes/100,000 individuals [95% CI] were observed, most pronounced in cases aged 40-< 50 years with myocardial infarction (305 [293-319] vs. 36 [36-37], p < 0.001). Higher proportions of complications and longer hospital stays were found for all procedures and morbidities in cases with diabetes.

CONCLUSION

Earlier hospitalizations, longer hospital stays and more complications in inpatient cases with diabetes together with the predicted future increase in diabetes prevalence depict huge challenges for the German healthcare system. There is an urgent need for developing strategies to adequately care for patients with diabetes in hospital.

The Effect of Diabetes and Metabolic Syndrome on Spine Surgery Outcomes

PURPOSE OF REVIEW

Diabetes and metabolic syndrome are highly prevalent in patients undergoing spine surgery. This review aims to capture both the findings of recently published literature investigating the effects of diabetes and metabolic syndrome on spine surgery outcomes and the current best practices in patient management.

RECENT FINDINGS

Diabetes and metabolic syndrome both contribute to worse outcomes in patients undergoing spine surgery. Although patients with diabetes are at greater risk of complications, those with uncontrolled diabetes experience increased healthcare costs and greater odds of postoperative complications. Furthermore, metabolic syndrome is repeatedly shown to have an adverse effect on spine surgery outcomes, including healthcare costs and medical complications. Spine surgeons should coordinate care with primary care physicians to optimize the preoperative profile of patients with comorbidities like diabetes and metabolic syndrome to minimize operative risk. With the shift to value-based care, understanding the patient factors that lead to complications is becoming increasingly important. Future studies should build upon the current literature and design preoperative interventions for at-risk patients. Additionally, further research is needed to analyze the modulatory effects of the social determinants of health in patients with diabetes and metabolic syndrome.

The Effect of Diabetes Mellitus on the Neurological Function of Patients with Cervical Spondylotic Myelopathy

OBJECTIVE

To evaluate the clinical value of diabetes mellitus for diagnosis and postoperative prognosis in patients with cervical spondylotic myelopathy undergoing anterior decompression and fusion.

METHODS

A total of 84 Patients (50 males and 34 females) who underwent anterior decompression and fusion were reviewed in this single-center retrospective study. The patients were divided into two groups (44 patients in the diabetes mellitus group and 40 in the non-diabetic group). Clinical manifestations were evaluated, including characteristics baseline, clinical tests, MRI information, clinical scores, and complications. The predictive effect of diabetes mellitus on clinical scores were assessed via the receiver operating characteristic curve. The correlation between the severity of diabetes mellitus and neurological function recovery was estimated using the Pearson correlation coefficient.

RESULTS

Patients with diabetes mellitus exhibited a higher ratio of hyperintensity of the spinal cord (P < 0.05) and worse preoperative clinical scores and neurological recovery (all P < 0.05). Receiver operating characteristic curve results indicated that diabetes mellitus could serve as a good indicator for preoperative evaluation of the Japanese Orthopedic Association (JOA) score (area under curve [AUC] = 0.639), visual analogue score (AUC = 0.642), and Nurick score (AUC = 0.740). In addition, analysis of JOA in isolation suggested that diabetes mellitus correlated closely with the sensory function in the upper and lower limbs (both P < 0.01). The Receiver operating characteristic curve also demonstrated that diabetes mellitus as a clinical test had a reasonable specificity for sensory function in the upper (AUC = 0.654) and lower limbs (AUC = 0.671). Both the level of HbA1c and the duration of diabetes mellitus were negatively correlated with the recovery rate of the JOA score. There was no significant difference between the perioperative complications between the two groups (P > 0.05).

CONCLUSION

This present study revealed that the neurological impairment caused by diabetes mellitus in patients undergoing anterior decompression and fusion does not only affect postoperative functional recovery but also interferes with the preoperative clinical manifestations, especially the sensory function in the upper and lower limbs.

Optimal hemoglobin A1C target in diabetics undergoing elective cervical spine surgery

BACKGROUND CONTEXT

Diabetes mellitus (DM) is a well-established risk factor for suboptimal outcomes following cervical spine surgery. Hemoglobin A1C (HbA1c), a surrogate for long-term glycemic control, is a valuable assessment tool in diabetic patients.

PURPOSE

In patients undergoing elective cervical spine surgery, we sought to identify optimal HbA1c levels to: (1) maximize 1-year postoperative patient-reported outcomes (PROs), and (2) predict the occurrence of medical and surgical complications.

STUDY DESIGN/SETTING

A retrospective cohort study using prospectively collected data was performed in a single academic center.

PATIENT SAMPLE

Diabetic patients undergoing elective anterior cervical fusion and posterior cervical laminectomy and fusion (PCLF) between October 2010-March 2021 were included.

OUTCOME MEASURES

Primary outcomes included Numeric Rating Scale (NRS)-Neck pain, NRS-Arm pain, and Neck Disability Index (NDI). Secondary outcomes included surgical site infection (SSI), complications, readmissions, and reoperations within 90-days postoperatively.

METHODS

HbA1c, demographic, comorbidity, and perioperative variables were gathered in diabetic patients only. PROs were analyzed as continuous variables and minimum clinically difference (MCID) was set at 30% improvement from baseline.

RESULTS

Of 1992 registry patients undergoing cervical surgery, 408 diabetic patients underwent cervical fusion surgery. Anterior: A total of 259 diabetic patients underwent anterior cervical fusion, 141 of which had an available HbA1c level within one year prior to surgery. Mean age was 55.8±10.1, and mean HbA1c value was 7.2±1.4. HbA1c levels above 6.1 were associated with failure to achieve MCID for NDI (AUC=0.77, 95%CI 0.70-0.84, p<.001), and HbA1c levels above 6.8 may be associated with increased odds of reoperation (AUC=0.61, 95%CI 0.52-0.69, p=.078). Posterior: A total of 149 diabetic patients underwent PCLF, 65 of which had an available HbA1c level within 1 year. Mean age was 63.6±9.2, and mean HbA1c value was 7.2±1.5. Despite a low AUC for NRS-Arm pain and readmission, HbA1c levels above 6.8 may be associated with failure to achieve MCID for NRS-Arm pain (AUC=0.61, 95%CI 0.49-0.73, p=.094), and HbA1c levels above 7.6 may be associated with higher readmission rate (AUC=0.63, 95%CI 0.50-0.75, p=.185).

CONCLUSIONS

In a cohort of diabetic patients undergoing elective cervical spine surgery, HbA1c levels above 6.1 were associated with decreased odds of achieving MCID for NDI in anterior cervical fusion surgery. Though only moderate associations were seen for the select outcomes of reoperation (6.8), readmission (7.6), and MCID for NRS-Arm pain (6.8), preoperative optimization of HbA1c using these levels as benchmarks should be considered to reduce the risk of complications and maximize PROs for patients undergoing elective cervical spine surgery.

Effect of Diabetes Mellitus on Implant Osseointegration of Titanium Screws: An Animal Experimental Study

Objective

To explore the effect of diabetes mellitus (DM) on implant osseointegration of titanium screws.

Methods

Sixty rats were randomly divided into a DM group and a control group (each group, n = 30). DM group rats were injected with 1% Streptozotocin solution at 65 mg/kg to establish a DM model. Titanium screws were implanted into the rats' distal femurs in both groups. The rats were sacrificed for micro‐CT scanning, micro‐indentation, biomechanical detection, confocal Raman microspectroscopy, and histological and histomorphometric analysis at 4, 8, and 12 weeks post‐implantation, respectively. Messenger RNA (mRNA) expression and protein expression of the related growth factors around the implant were analyzed using real‐time polymerase chain reaction and Western blots.

Results

At 4, 8 and 12 weeks, micro‐CT scanning, hematoxylin‐eosin (HE) staining, Gieson's acid‐magenta staining, and fluorescent labeled staining showed disorder in the bone tissue arrangement, a lack of new bone tissue, poor maturity and continuity, and poor trabecular bone parameters around the implant in the DM group. At 4, 8, and 12 weeks, the interfacial bone binding rate in the DM group was significantly lower (16.2% ± 4.8%, 25.7% ± 5.7%, 42.5% ± 5.8%, respectively) than that in the control group (23.6% ± 5.2%, 40.8% ± 6.3%, 64.2% ± 7.3%, respectively; P < 0.05). At 8 and 12 weeks, the elastic modulus (17.0 ± 1.8 and 15.1 ± 1.5 GPa, respectively) and trabecular bone hardness (571 ± 39 and 401 ± 37 MPa, respectively) in the DM group were significantly lower than the elastic modulus (23.4 ± 2.3 and 23.8 ± 1.8 GPa, respectively) and trabecular bone hardness (711 ± 45 and 719 ± 46 MPa, respectively) in the control group (P < 0.05). The maximum load required for the prosthesis pull‐out experiment in the DM group at 4, 8, and 12 weeks (55.14 ± 6.74 N, 73.34 ± 8.43 N, and 83.45 ± 8.32 N, respectively) was significantly lower than that in the control group (77.45 ± 7.48 N, 93.28 ± 8.29 N, and 123.62 ± 9.43 N, respectively, P < 0.05). At 8 and 12 weeks, the mineral‐to‐collagen ratio in the DM group (6.56 % ± 1.35% and 4.45%± 1.25%, respectively) was significantly higher than that in the control group (5.31% ± 1.42% and 3.62% ± 1.33%, respectively, P < 0.05). At 12 weeks, mRNA and protein expression levels of bone morphogenetic protein 2, transforming growth factor‐β1, vascular endothelial growth factor, osteopontin, osteocalcin, and runt‐related transcription factor 2 in the DM group were significantly lower than that in the control group.

Conclusions

DM can negatively affect bone osseointegration, manifesting as disorder in bone tissue arrangement around the implant, a lack of new bone tissue, poor maturity and continuity, poor trabecular bone parameters and lower expression of the related growth factors.

Diabetes mellitus and perioperative outcomes: a scoping review of the literature

BACKGROUND

Diabetes mellitus (DM) is frequently encountered in the perioperative period. DM may increase the risk of adverse perioperative outcomes owing to the potential vascular complications of DM. We conducted a scoping review to examine the association between DM and adverse perioperative outcomes.

METHODS

A systematic search strategy of the published literature was built and applied in multiple databases. Observational studies examining the association between DM and adverse perioperative outcomes were included. Abstract screening determined full texts suitable for inclusion. Core information was extracted from each of the included studies including study design, definition of DM, type of DM, surgical specialties, and outcomes. Only primary outcomes are reported in this review.

RESULTS

The search strategy identified 2363 records. Of those, 61 were included and 28 were excluded with justification. DM was mostly defined by either haemoglobin A1c (HbA1c) or blood glucose values (19 studies each). Other definitions included 'prior diagnosis' or use of medication. In 17 studies the definition was unclear. Type 2 DM was the most frequently studied subtype. Five of seven studies found DM was associated with mortality, 5/13 reported an association with 'complications' (as a composite measure), and 12/17 studies found DM was associated with 'infection'. Overall, 33/61 studies reported that DM was associated with the primary outcome measure.

CONCLUSION

Diabetes mellitus is inconsistently defined in the published literature, which limits the potential for pooled analysis. Further research is necessary to determine which cohort of patients with DM are most at risk of adverse postoperative outcomes, and how control influences this association.

Sinonasal Packing is Not a Requisite for Successful Cerebrospinal Fluid Leak Repair

Background Numerous methods have been described to repair nasal cerebrospinal fluid (CSF) leaks. Most studies have focused on optimizing CSF leak repair success, leading to closure rates of 90 to 95%.

Objective This study aimed to determine if excellent reconstruction rates could be achieved without using sinonasal packing.

Methods A prospective case series of 73 consecutive patients with various CSF leak etiologies and skull base defects was conducted to evaluate reconstruction success without sinonasal packing. The primary outcome measure was postoperative CSF leak. Secondary outcome measures were postoperative epistaxis requiring intervention in operating room or emergency department, infectious sinusitis, and 22-item sinonasal outcome test (SNOT-22) changes.

Results Mean age was 54.5 years and 64% were female. Multilayered reconstructions were performed in 55.3% of cases, with collagen or bone epidural inlay grafts, and nasal mucosal grafts or nasoseptal flaps for onlay layers. Onlay-only reconstructions with mucosal grafts or nasoseptal flaps were performed in 44.7% of cases. Tissue sealants were used in all cases, and lumbar drains were used in 40.8% of cases. There were two initial failures (97.4% initial success), but both resolved with lumbar drains alone (no revision surgeries). There were no instances of postoperative epistaxis requiring intervention in the operating room or emergency department. Infectious sinusitis occurred in 2.7% of patients in the first 3 months postoperatively. SNOT-22 did not change significantly from preoperatively to first postoperative visits, then improved over time.

Conclusion Nasal CSF leaks from various etiologies and defect sites were successfully repaired without using sinonasal packing, and patients experienced minimal sinonasal morbidity.

A national snapshot of the impact of clinical depression on post-surgical pain and adverse outcomes after anterior cervical discectomy and fusion for cervical myelopathy and radiculopathy: 10-year results from the US Nationwide Inpatient Sample

Depression is associated with poorer outcomes in a wide spectrum of surgeries but the specific effects of depression in patients undergoing cervical spine surgery are unknown. This study aimed to evaluate the prevalence and impact of pre-surgical clinical depression on pain and other outcomes after surgery for cervical degenerative disc disease using a national representative database. Data of patients with cervical myelopathy and radiculopathy were extracted from the 2005–2014 US Nationwide Inpatient Sample (NIS) database. Included patients underwent anterior discectomy and fusion (ACDF). Acute or chronic post-surgical pain, postoperative complications, unfavorable discharge, length of stay (LOS) and hospital costs were evaluated. Totally 215,684 patients were included. Pre-surgical depression was found in 29,889 (13.86%) patients, with a prevalence nearly doubled during 2005–2014 in the US. Depression was independently associated with acute or chronic post-surgical pain (aOR: 1.432), unfavorable discharge (aOR: 1.311), prolonged LOS (aOR: 1.152), any complication (aOR: 1.232), respiratory complications/pneumonia (aOR: 1.153), dysphagia (aOR: 1.105), bleeding (aOR: 1.085), infection/sepsis (aOR: 1.529), and higher hospital costs (beta: 1080.640) compared to non-depression. No significant risk of delirium or venous thrombotic events was observed in patients with depression as compared to non-depression. Among patients receiving primary surgery, depression was independently associated with prolonged LOS (aOR: 1.150), any complication (aOR:1.233) and postoperative pain (aOR:1.927). In revision surgery, no significant associations were found for prolonged LOS, any complication or pain. In conclusion, in the US patients undergoing ACDF, pre-surgical clinical depression predicts post-surgical acute or chronic pain, a slightly prolonged LOS and the presence of any complication. Awareness of these associations may help clinicians stratify risk preoperatively and optimize patient care.

Incidence and Clinical Outcomes of Hypothyroidism in Patients Undergoing Spinal Fusion

Background

Hypothyroidism has been independently associated with the development of several comorbidities and is known to increase complication rates in non-spinal surgeries. However, there are limited data regarding the effects of hypothyroidism in major spine surgery. Therefore, we present the largest retrospective analysis evaluating outcomes in hypothyroid patients undergoing spinal fusion.

Methods

A retrospective review of the National Inpatient Sample (NIS) from 2004-2014 was performed. Patients with an International Classification of Diseases, 9th revision, Clinical Modification (ICD-9-CM) procedure code indicating spinal fusion (81.04-81.08, 81.34-81.38, 81.0x, 81.3x) were included. Patients with an ICD-9-CM diagnosis code indicating hypothyroidism (244.x) were compared to those without. Cervical and lumbar fusions were evaluated independently. Significant covariates in univariable logistic regression were utilized to construct multivariable models to analyze the effect of hypothyroidism on perioperative morbidity and mortality.

Results

A total of 4,149,125 patients were identified, of which 9.4% were hypothyroid. Although, hypothyroid patients had a higher risk of hematologic complications (lumbar - odds ratio [OR] 1.176, p < 0.0001; cervical - OR 1.162, p < 0.0001), they exhibited decreased in-hospital mortality (lumbar - OR .643, p < 0.0001; cervical - OR .606, p < 0.0001). Hypothyroid lumbar fusion patients also demonstrated decreased rates of perioperative myocardial infarction (MI) (OR .851, p < 0.0001). All these results were independent of patient gender.

Conclusions

Hypothyroid patients undergoing spinal fusion demonstrated lower rates of inpatient mortality and, in lumbar fusions, also had lower rates of acute MI when compared to their euthyroid counterparts. This suggests that hypothyroidism may offer protection against all-cause mortality and may be cardioprotective in the postoperative period for lumbar spinal fusions independent of patient gender.

Impact of Diabetes Mellitus on Cervical Spine Surgery for Ossification of the Posterior Longitudinal Ligament

Ossification of the posterior longitudinal ligament (OPLL) is commonly associated with diabetes mellitus (DM); however, the impact of DM on cervical spine surgery for OPLL remains unclear. This study was performed to evaluate the influence of diabetes DM on the outcomes following cervical spine surgery for OPLL. In total, 478 patients with cervical OPLL who underwent surgical treatment were prospectively recruited from April 2015 to July 2017. Functional measurements were conducted at baseline and at 6 months, 1 year, and 2 years after surgery using JOA and JOACMEQ scores. The incidence of postoperative complications was categorized into early (≤30 days) and late (>30 days), depending on the time from surgery. From the initial group of 478 patients, 402 completed the 2-year follow-up and were included in the analysis. Of the 402 patients, 127 (32%) had DM as a comorbid disease. The overall incidence of postoperative complications was significantly higher in patients with DM than in patients without DM in both the early and late postoperative periods. The patients with DM had a significantly lower JOA score and JOACMEQ scores in the domains of lower extremity function and quality of life than those without DM at the 2-year follow-up.

Smoking Is an Independent Risk Factor for 90-Day Readmission and Reoperation Following Posterior Cervical Decompression and Fusion

BACKGROUND

Posterior cervical decompression and fusion (PCF) is a common procedure used to treat various cervical spine pathologies, but the 90-d outcomes following PCF surgery continue to be incompletely defined.

OBJECTIVE

To identify risk factors associated with 90-d readmission and reoperation following PCF surgery.

METHODS

Adults undergoing PCF from 2012 to 2020 were identified. Demographic and radiographic data, surgical characteristics, and 90-d outcomes were collected. Univariate analysis was performed using Student's t-test, chi square, and Fisher exact tests as appropriate. Multivariable logistic regression models with lasso penalty were used to analyze various risk factors.

RESULTS

A total of 259 patients were included. The 90-d readmission and reoperation rates were 9.3% and 4.6%, respectively. The most common reason for readmission was surgical site infection (SSI) (33.3%) followed by new neurological deficits (16.7%). Patients who smoked tobacco had 3-fold greater odds of readmission compared to nonsmokers (odds ratio [OR]: 3.48; 95% CI 1.87-6.67; P = .0001). Likewise, the most common reason for reoperation was SSI (33.3%) followed by seroma and implant failure (25.0% each). Smoking was also an independent risk factor for reoperation, associated with nearly 4-fold greater odds of return to the operating room (OR: 3.53; 95% CI 1.53-8.57; P = .003).

CONCLUSION

Smoking is a significant predictor of 90-d readmission and reoperation in patients undergoing PCF surgery. Smoking cessation should be strongly considered preoperatively in elective PCF cases to minimize the risk of 90-d readmission and reoperation.

Diabetes Mellitus Does Not Impact Achievement of a Minimum Clinically Important Difference Following Anterior Cervical Discectomy and Fusion

BACKGROUND

Diabetes mellitus (DM) has been identified as a risk factor for poorer outcomes following anterior cervical discectomy and fusion (ACDF). This study aims to evaluate the impact DM has on achievement of MCID (minimum clinically important difference) following ACDF.

METHODS

A surgical database was reviewed for patients who underwent primary, single-level ACDF procedures with posterior instrumentation. Visual analog scales (VAS) Arm and Neck, Neck Disability Index (NDI), and Patient-Reported Outcomes Measurement Information System (PROMIS) and 12-item Short Form (SF-12) scores for physical function (PF) were recorded. MCID achievement was calculated using pre-established values from the literature. Intergroup differences in demographic, perioperative characteristics, mean outcome scores and rates of MCID achievement were calculated.

RESULTS

There were 43 patients with diabetes and 320 patients without diabetes. DM status was significantly associated with age, ethnicity, hypertension, American Society of Anesthesiologists physical classification score, Charlson Comorbidity Index, and insurance type (all P ≤ 0.041). Postoperative length of stay was significantly greater for the DM group (P = 0.011). Mean VAS Arm and NDI differed at 6 months (P ≤ 0.049, both) and PROMIS-PF differed from 6 weeks through 6 months (P ≤ 0.039, all). Patients without diabetes significantly improved in all PROMs by 1 year postoperatively (P < 0.01, all). Patients with diabetes significantly improved in VAS Neck and Arm, SF-12 physical component score, and PROMIS-PF by 1 year (all P ≤ 0.013) but NDI significantly improved only at 12 weeks (P = 0.038). Intergroup differences for MCID achievement were demonstrated at 6 months for NDI and SF-12 physical component score (P ≤ 0.008).

CONCLUSIONS

Although moderate intergroup differences in MCID achievement were demonstrated, the results of this study suggest that patients may realize similar benefits of ACDF surgery regardless of DM status.

Accidental Dural Tears in Minimally Invasive Spinal Surgery for Degenerative Lumbar Spine Disease

Background: One of the most frequent complications of spinal surgery is accidental dural tears (ADTs). Minimal access surgical techniques (MAST) have been described as a promising approach to minimizing such complications. ADTs have been studied extensively in connection with open spinal surgery, but there is less literature on minimally invasive spinal surgery (MISS).

Materials and Methods: We reviewed 187 patients who had undergone degenerative lumbar spinal surgery using minimally invasive spinal fusions techniques. We analyzed the influence of age, Body Mass Index (BMI), smoking, diabetes, and previous surgery on the rate of ADTs in MISS.

Results: Twenty-two patients (11.764%) suffered from an ADT. We recommended bed rest for two and a half to 5 days, depending on the type of repair required and the amount of cerebrospinal fluid (CSF) leakage. We could not find any statistically significant correlation between ADTs and age (p = 0.34,), BMI (p = 0.92), smoking (p = 0.46), and diabetes (p = 0.71). ADTs were significantly more frequent in cases of previous surgery (p < 0.001). None of the patients developed a transcutaneous CSF leak or post-operative infection.

Conclusions: The frequency of ADTs in MISS appears comparable to that encountered when using open surgical techniques. Additionally, MAST produces less dead space along the corridor to the spine. Such reduced dead space may not be enough for pseudomeningocele to occur, cerebrospinal fluid to accumulate, and fistula to form. MAST, therefore, provides a certain amount of protection.

Association of Preoperative Hemoglobin A1c and Body Mass Index with Wound Infection Rate in Spinal Surgery

BACKGROUND

The deleterious effect of diabetes mellitus on surgical outcomes is well documented for joint replacement surgery. We analyzed the large national US Department of Veterans Affairs (VA) database for patients who had undergone elective spinal surgery.

METHODS

We retrospectively searched the VA database and identified 174 520 spine cases.

RESULTS

There were 7766 (4.5%) wound infections and 49 271 (28%) had hemoglobin A1c (HbA1c) testing (range: 3.0-17.8) prior to surgery. In the preoperative HbA1c-checked group, there were 2941 (6.0% of 49 271) infections and in the without-preoperative HbA1c group, there were 4825 (3.9% of 125 249) infections. The distribution of infections was significantly different (χ² = 372.577, P < .0001) and suggests a 2.12% increase in the absolute risk of infection based on the presence of preoperative HbA1c testing, regardless of the result. Logistic regression revealed a preoperative HbA1c test was associated with an odds ratio of 1.435 for infection (confidence interval 1.367-1.505, P < .0001). In a separate model based on HbA1c levels, we found that HbA1c is a significant predictor of infection with an odds ratio of 1.042 (confidence interval 1.017-1.068, P = .0009) for each 1% increase in the test result. This analysis differs from using a strict cutoff value of HbA1c of 6.5%. Similar testing for body mass index and age yielded an odds ratio of 1.027 for each increase of 1 kg/m² and an odds ratio of 1.009 for each 1-year increase in age respectively.

CONCLUSIONS

Hemoglobin A1c testing, HgA1c value, body mass index, and age all contribute to the risk of wound infection after elective spine surgery in a large national VA population. These data can be used to estimate surgical risks and to aid in patient counseling about proposed spine surgery.

LEVEL OF EVIDENCE

4.

Two-Year Clinical and Radiological Outcomes in Patients With Diabetes Undergoing Single-Level Anterior Cervical Discectomy and Fusion

STUDY DESIGN

Secondary analysis of data from the multicenter, randomized, parallel-controlled Food and Drug Administration (FDA) investigational device exemption study.

OBJECTIVE

Studies on outcomes following anterior cervical discectomy and fusion (ACDF) in individuals with diabetes are scarce. We compared 24-month radiological and clinical outcomes in individuals with and without diabetes undergoing single-level ACDF with either i-FACTOR or local autologous bone.

METHODS

Between 2006 and 2013, 319 individuals with single-level degenerative disc disease (DDD) and no previous fusion at the index level underwent ACDF. The presence of diabetes determined the 2 cohorts. Data collected included radiological fusion evaluation, neurological outcomes, Neck Disability Index (NDI), Visual Analog Scale (VAS) scores, and the 36-Item Short Form Survey Version 2 (SF-36v2) Physical and Mental component summary scores.

RESULTS

There were 35 individuals with diabetes (11.1%; average body mass index [BMI] = 32.99 kg/m²; SD = 5.72) and 284 without (average BMI = 28.32 kg/m²; SD = 5.67). The number of nondiabetic smokers was significantly higher than diabetic smokers: 73 (25.70%) and 3 (8.57%), respectively. Preoperative scores of NDI, VAS arm pain, and SF-36v2 were similar between the diabetic and nondiabetic participants at baseline; however, VAS neck pain differed significantly between the cohorts at baseline (P = .0089). Maximum improvement for NDI, VAS neck and arm pain, and SF-36v2 PCS and MCS scores was seen at 6 months in both cohorts and remained stable until 24 months.

CONCLUSIONS

ACDF is effective for cervical radiculopathy in patients with diabetes. Diabetes is not a contraindication for patients requiring single-level surgery for cervical DDD.

Predictors of Readmission and Prolonged Length of Stay After Cervical Disc Arthroplasty

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

The aim of the study was to assess which factors increase risk of readmission within 30 days of surgery or prolonged length of stay (LOS) (≥2 days) after cervical disc arthroplasty (CDA).

SUMMARY OF BACKGROUND DATA

Several studies have shown noninferiority at mid- and long-term outcomes after cervical disc arthroplasty (CDA) compared to anterior cervical discectomy and fusion ACDF, but few have evaluated short-term outcomes regarding risk of readmission or prolonged LOS after surgery.

METHODS

Demographics, comorbidities, operative details, postoperative complications, and perioperative outcomes were collected for patients undergoing single level CDA in the National Surgical Quality Improvement Program (NSQIP) database. Patients with prolonged LOS, defined as >2 days, and readmission within 30 days following CDA were identified. Univariable and multivariable logistic regression models were used to identify risk factors for prolonged LOS and readmission.

RESULTS

A total of 3221 patients underwent single level CDA. Average age was 45.6 years (range 19-82) and 53% of patients were male. A total of 472 (14.7%) experienced a prolonged LOS and 36 (1.1%) patients were readmitted within 30 days following surgery. Predictors of readmission were postoperative superficial wound infection (odds ratio [OR] = 73.83, P < 0.001), American Society of Anesthesiologists (ASA) classification (OR = 1.98, P = 0.048), and body mass index (BMI) (OR = 1.06, P = 0.02). Female sex (OR = 1.76, P < 0.001), diabetes (OR = 1.50, P = 0.024), postoperative wound dehiscence (OR = 13.11, P = 0.042), ASA class (OR = 1.43, P < 0.01), and operative time (OR = 1.01, P < 0.001) were significantly associated with prolonged LOS.

CONCLUSION

From a nationwide database analysis of 3221 patients, wound complications are predictors of both prolonged LOS and readmission. Patient comorbidities, including diabetes, higher ASA classification, female sex, and higher BMI also increased risk of prolonged LOS or readmission.Level of Evidence: 3.

Diabetes Does Not Increase Complications, Length of Stay, or Hospital Costs After Minimally Invasive Transforaminal Lumbar Interbody Fusion

STUDY DESIGN

Retrospective cohort.

OBJECTIVE

To determine if the presence of diabetes mellitus as comorbidity is associated with complications, inpatient length of stay, or direct hospital costs after minimally invasive transforaminal lumbar interbody fusion (MIS TLIF).

SUMMARY OF BACKGROUND DATA

Very few studies have investigated the effect of diabetes on complications, length of stay, or costs in minimally invasive lumbar surgeries.

METHODS

Patients undergoing primary, single-level MIS TLIF were retrospectively reviewed. Diabetic and nondiabetic patients were propensity matched in a 1:1 manner for age, sex, and comorbidity burden. An association between diabetic status and preoperative demographic or perioperative variables, including inpatient length of stay, was tested for using Student t test or χ analysis. Multivariate linear regression was used to test for an association between diabetic status and direct hospital costs.

RESULTS

After 1:1 propensity matching, 100 patients were included in this analysis. There were no significant differences in age, sex, body mass index, smoking status, or Charlson Comorbidity Index between propensity-matched patients with and without diabetes. In regards to the length of stay, no significant differences existed between diabetic and nondiabetic groups (68.7 vs. 58.3 h, P=0.218). No other significant differences existed in other perioperative variables including operative time, intraoperative blood loss, or complication rate (P≥0.05 for each). Multivariate analysis indicated that diabetic status was not associated with differences in total direct hospital costs (US$20,428 vs. US$20,429, P=0.792) or cost subcategories after MIS TLIF (P≥0.05 for each).

CONCLUSIONS

In this investigation, diabetes was not associated with postoperative complication rates, inpatient length of stay, or direct hospital costs after primary, single-level MIS TLIF. The reduced extent of operative exposure and tissue trauma in MIS TLIF may mitigate the risk of complications in diabetic patients, possibly preventing extensions in hospital stay length and associated hospital costs.

Long-Term Effect of Diabetes on Reoperation After Lumbar Spinal Surgery: A Nationwide Population-Based Sample Cohort Study

BACKGROUND

Diabetes mellitus (DM) is associated with poor postoperative outcomes and increased morbidity after surgeries. Some previous studies have addressed the close association between DM and those leading to reoperations, whereas others have rejected this theory. This study aimed to evaluate the long-term effect of DM on lumbar spinal surgery using data from a nationwide sample cohort.

METHODS

A population-based cohort comprised one million people, which is a 2.1% representative sample of the Korean population. The present study included adult patients with lumbar degenerative diseases (e.g., lumbar spinal stenosis and spondylolisthesis), who underwent their first lumbar surgery in 2006. The cumulative incidence function for reoperation was calculated and multivariate analysis was performed to define correlation between reoperation and independent factors.

RESULTS

A total of 2020 patients were enrolled and followed up for 10 years. Nondiabetic patients, patients with DM without complication (DwoC), and patients with DM with complication (DwC) accounted for 79.5%, 9.36%, and 11.14% of all patients, respectively. Reoperation incidence stratified by DM was 12.7% for nondiabetic patients, 22.2% for patients with DwoC, and 20.0% for patients with DwC in 10 years of follow-up. During the same period, death, a competing event of reoperation, occurred in 7.8% of nondiabetic patients, in 13.2% of patients with DwoC, and in 20.9% of patients with DwC.

CONCLUSIONS

DM increased 1.65 times the overall cumulative incidences of reoperation after lumbar spinal surgeries for 10 years of follow-up. The reoperation incidence for DwC may be lower than that for DwoC because of a high incidence of death as a competing event of reoperation.

Risk factors and outcomes of diabetic foot ulcer among diabetes mellitus patients admitted to Nekemte referral hospital, western Ethiopia: Prospective observational study

Objectives

Diabetic foot ulcer is one of the complications of diabetes mellitus. The diabetic patients with foot infections especially gangrene require long-term hospitalization and carry the risk of limb amputation. Despite these challenges, there are a scarce studies done on risk factors and no finding on outcomes of diabetic foot ulcers in Ethiopia.

Patients and methods

A prospective observational study was conducted among diabetes patients with diabetic foot ulcer at Nekemte referral hospital from March 15 to June 15, 2018.

Results

Of the 115 diabetes foot ulcer patients admitted to Nekemte referral hospital, 64(55.65%) were males and the mean age of participants was 44.4 ± 14.7 years. Fifty-eight (50.43%) of the patients had chronic health problems and 56(48.69%) had diabetic complications. Of patients with complications, 35(30.43%) were undergone amputations. Diabetic foot ulcer grade ≥4 (AOR = 1.7; 95% CI: 1.604, 4.789), inappropriate antibiotics use (AOR = 2.526; 95% CI: 1.767, 8.314), overweight (AOR = 2.767; 95% CI: 1.827, 9.252), obesity (AOR = 3.020; 95% CI: 2.556, 16.397), poor blood glucose control (AOR = 2.592; 95% CI: 1.937, 7.168) and neuropathy (AOR = 1.565; 95% CI: 1.508, 4.822) were predictors of amputation up on multivariable logistic regression analysis.

Conclusion

Blood glucose level, higher body mass index, inappropriate antibiotics use, neuropathy and advanced grade of diabetic foot ulcer were independent predictors of amputation. Thus, special emphasis for patients having neuropathy and advanced grade of diabetic foot ulcer as well as weight reduction, managing hyperglycaemia, and appropriate antibiotics prescription practice would decrease untoward effects of diabetic foot ulcer.

•

Foot problems are common in people with diabetes throughout the world, affecting up to 15% of diabetic patients.

•

Diabetic foot complications is the major medical, social and economic problem for all types of diabetes.

•

Advanced diabetes foot infections are the most common diabetes-related cause of hospitalization.

•

Empiric antibiotic regimen is selected for diabetic foot infections on the basis of the likely etiologic agent(s).

•

Peripheral arterial disease (PAD) is present in one-half of all patients with foot ulcers.

PHQ-9 Score Predicts Postoperative Outcomes Following Minimally Invasive Transforaminal Lumbar Interbody Fusion

STUDY DESIGN

This was a retrospective cohort study.

OBJECTIVE

This study evaluates if an association exists between preoperative depression and postoperative outcomes following minimally invasive transforaminal lumbar interbody fusion (MIS TLIF).

SUMMARY OF BACKGROUND DATA

Few studies have quantified preoperative depression symptoms using Patient Health Questionnaire-9 (PHQ-9) to predict postoperative outcomes after lumbar fusion, especially MIS TLIF.

METHODS

A surgical database of patients undergoing primary, single-level MIS TLIF was retrospectively reviewed. Patients were stratified by predefined preoperative PHQ-9 scores: no depression (<5), mild depression (5-9), and moderate to severe depression (≥10). Inpatient pain scores and narcotics use were recorded. Oswestry Disability Index, Veterans RAND-12 Mental Component Score and Physical Component Score, and Visual Analog Scale (VAS) back and leg pain scores were collected preoperatively and at 6-week, 12-week, and 6-month follow-up. One-way analysis of variance and χ analysis determined if an association existed between PHQ-9 subgroups and baseline characteristics or perioperative outcomes. Multivariate linear regression assessed for an association between PHQ-9 and postoperative patient-reported outcomes.

RESULTS

In total, 94 patients were included. Patients with higher PHQ-9 scores were younger, obese, and carried workers' compensation insurance. Higher PHQ-9 scores were associated with worse preoperative Oswestry Disability Index, Veterans RAND-12 Mental Component Score and Physical Component Score, and VAS back and leg pain scores. Patients with higher PHQ-9 reported greater inpatient VAS pain scores on postoperative day 0 and 1 and demonstrated greater hourly narcotics consumption on postoperative day 0. Furthermore, higher PHQ-9 scores exhibited less improvement in all patient-reported outcomes.

CONCLUSIONS

Patients with severe depression symptoms reported greater pain, increased narcotics consumption, and less clinical improvement after MIS TLIF. Therefore, patients with greater PHQ-9 scores should be monitored more closely and may benefit from additional counseling with regard to postoperative outcomes to better manage pain control and expectations of recovery.

Effect of diabetes type on long-term outcome of epidermal axon regeneration

Objective

To assess the effect of diabetes type on the long‐term rate and extent of epidermal nerve regeneration.

Methods

Subjects with well controlled type 1 diabetes mellitus (n = 11) or type 2 diabetes mellitus (n = 36), with normal nerve conduction studies and baseline intraepidermal nerve fiber density (IENFD), and healthy controls (n = 10) underwent chemical axotomy of the intraepidermal nerves at the thigh using topical capsaicin. Skin biopsies were performed at 30, 90, 150, and 180 days post‐axotomy.

Results

After 180 days, IENFD in diabetic subjects remained significantly below baseline levels, while healthy controls returned to normal. At each time point, regeneration rates were significantly slower among diabetic subjects, although type 1 subjects regenerated significantly faster and achieved higher percentages of baseline IENFD compared with type 2.

Interpretation

Among diabetic patients, nerve injury recovery is likely to take significantly longer than in healthy individuals, and remains incomplete, particularly among type 2 patients. This may partially explain the progression of neuropathy among diabetic patients: damage accumulates because nerve recovery is slowed and incomplete. Furthermore, these findings support caution when recommending certain procedures, such as carpal tunnel repair, to patients with progressed diabetic disease.

Physical function computer adaptive test outcomes in diabetic lumbar spine surgical patients

BACKGROUND CONTEXT

Diabetes is a highly prevalent comorbid condition among patients undergoing spine surgery. Several studies have used legacy patient-reported outcome measures to implicate diabetes as a predictor of increased disability, pain, and decreased physical function and quality of life following spine surgery. The effect of diabetes on postoperative physical function has not yet been studied using the PROMIS Physical Function Computer Adaptive Test (PF CAT).

PURPOSE

To understand the effect of diabetes on physical function outcomes among patients undergoing lumbar spine surgery, as reported by the PF CAT.

STUDY DESIGN/SETTING

A retrospective cohort study was performed at a single university-based spine clinic.

PATIENT SAMPLE

Patients who underwent lumbar spine surgery between October 1, 2013 and April 26, 2018 with both PF CAT and Oswestry Disability Index (ODI) scores available for review.

OUTCOME MEASURES

PROMIS PF CAT. Secondary measures of disability included the ODI.

METHODS

PF CAT and ODI questionnaires were administered to patients via electronic tablets. Data from these questionnaires were collected prospectively, and retrieved from a university database. Wilcox tests, Exact Wilcox tests, linear regression models, and descriptive analytics were applied.

RESULTS

Patients meeting inclusion criteria included 233 nondiabetic patients and 65 diabetic patients. Mean PF CAT scores among diabetics were lower than those of nondiabetics at all time-points from preoperative through 12 months postoperative, with significance found at both 6 months (p=.035) and 12 months (p=.039) postoperative. Mean ODI scores among diabetics were significantly higher than those of nondiabetics at 3 months (p=.018) and 12 months (p=.027) postoperative. By 12 months postoperative, a smaller proportion of diabetics reached PF CAT and ODI minimum clinically important difference thresholds when compared to nondiabetics.

CONCLUSIONS

Diabetes is associated with lower PF CAT scores up to one year following lumbar spine surgery. However, many of these patients achieve meaningful improvement in physical function during this time. The PF CAT is consistent with legacy outcome measures in assessing outcomes in diabetic patients undergoing lumbar spine surgery, with an added benefit of decreased patient burden.

Elevated glycohemoglobin HbA1c is associated with low back pain in nonoverweight diabetics

BACKGROUND CONTEXT

Low back pain (LBP) is a common complaint in clinical practice of multifactorial origin. Although obesity has been thought to contribute to LBP primarily by altering the distribution of mechanical loads on the spine, the additional contribution of obesity-related conditions such as diabetes mellitus (DM) to LBP has not been thoroughly examined.

PURPOSE

To determine if there is a relationship between DM and LBP that is independent of body mass index (BMI) in a large cohort of adult survey participants.

STUDY DESIGN

Retrospective analysis of prospectively collected National Health and Nutrition Examination Survey (NHANES) data to characterize associations between LBP, DM, and BMI in adults subdivided into 6 subpopulations: normal weight (BMI 18.5-25), overweight (BMI 25-30), and obese (BMI >30) diabetics and nondiabetics. Diabetes was defined with glycohemoglobin A1c (HbA1c) ≥6.5%.

PATIENT SAMPLE

11,756 participants from NHANES cohort.

OUTCOME MEASURES

Percentage of LBP reported.

METHODS

LBP reported in the 1999-2004 miscellaneous pain NHANES questionnaire was the dependent variable examined. Covariates included HbA1c, BMI, age, and family income ratio to poverty as continuous variables as well as race, gender, and smoking as binary variables. Individuals were further subdivided by weight class and diabetes status. Regression and graphical analyses were performed on the study population as a whole and also on subpopulations.

RESULTS

Increasing HbA1c did not increase the odds of reporting LBP in the full cohort. However, multivariate logistic regression of the 6 subpopulations revealed that the odds of LBP significantly increased with increasing HbA1c levels in normal weight diabetics. No other subpopulations reported significant relationships between LBP and HbA1c. LBP was also significantly associated with BMI for normal weight diabetics and also for obese subjects regardless of their DM status.

CONCLUSIONS

LBP is significantly related to DM status, but this relationship is complex and may interact with BMI. These results support the concept that LBP may be improved in normal weight diabetic subjects with improved glycemic control and weight loss, and that all obese LBP subjects may benefit from improved weight loss alone.

The Effect of Preoperative Medications on Length of Stay, Inpatient Pain, and Narcotics Consumption After Minimally Invasive Transforaminal Lumbar Interbody Fusion

STUDY DESIGN

This is a retrospective cohort study.

OBJECTIVE

To determine the association between preoperative medications and length of stay, inpatient pain, and narcotics consumption after a minimally invasive transforaminal lumbar interbody fusion (MIS TLIF).

SUMMARY OF BACKGROUND DATA

Previous studies have identified risk factors for increased length of hospital stay, inpatient pain, and narcotics consumption. However, little is known regarding the effects of preoperative medications on outcomes after spine surgery.

METHODS

A prospectively maintained surgical database of patients undergoing primary, single-level MIS TLIF was retrospectively reviewed. Preoperative medications taken within 30 days before surgery were recorded for each patient and categorized by medication type. Poisson regression with robust error variance was used to determine the association between preoperative medications and length of stay, pain scores, and narcotics consumption. Multivariate analysis was performed using a backwards, stepwise regression to identify independent risk factors.

RESULTS

In total, 138 patients were included in this analysis. On bivariate analysis, benzodiazepines were associated with longer hospital stays [relative risk (RR)=2.03; P=0.031]. Benzodiazepines (RR=3.71; P<0.001) and preoperative narcotics (RR=2.60; P=0.012) were risk factors for pain ≥7 on postoperative day 0. On multivariate analysis, benzodiazepines were an independent risk factor for prolonged stay. Benzodiazepines, narcotics, and nonsteroidal anti-inflammatories were identified as independent risk factors for increased postoperative pain.

CONCLUSIONS

These results suggest that benzodiazepines are a risk factor for increased length of stay and postoperative pain after MIS TLIF. Preoperative narcotics and nonsteroidal anti-inflammatories were also identified as risk factors for postoperative pain though this did not lead to increases in narcotics consumption. Patients taking these medications should undergo more vigilant perioperative monitoring for adequate pain management. More work must be done to further elucidate the association between preoperative medications and postoperative outcomes after MIS TLIF.

Dietary advanced glycation end-product consumption leads to mechanical stiffening of murine intervertebral discs

Back pain is a leading cause of disability and is strongly associated with intervertebral disc (IVD) degeneration. Reducing structural disruption and catabolism in IVD degeneration remains an important clinical challenge. Pro-oxidant and structure-modifying advanced glycation end-products (AGEs) contribute to obesity and diabetes, which are associated with increased back pain, and accumulate in tissues due to hyperglycemia or ingestion of foods processed at high heat. Collagen-rich IVDs are particularly susceptible to AGE accumulation due to their slow metabolic rates, yet it is unclear whether dietary AGEs can cross the endplates to accumulate in IVDs. A dietary mouse model was used to test the hypothesis that chronic consumption of high AGE diets results in sex-specific IVD structural disruption and functional changes. High AGE diet resulted in AGE accumulation in IVDs and increased IVD compressive stiffness, torque range and failure torque, particularly for females. These biomechanical changes were likely caused by significantly increased AGE crosslinking in the annulus fibrosus, measured by multiphoton imaging. Increased collagen damage measured with collagen hybridizing peptide did not appear to influence biomechanical properties and may be a risk factor as these animals age. The greater influence of high AGE diet on females is an important area of future investigation that may involve AGE receptors known to interact with estrogen. We conclude that high AGE diets can be a source for IVD crosslinking and collagen damage known to be important in IVD degeneration. Dietary modifications and interventions that reduce AGEs warrant further investigation and may be particularly important for diabetics, in whom AGEs accumulate more rapidly.

Summary: Dietary AGEs lead to sex-specific intervertebral disc structural and functional changes and may be targeted for promoting spinal health, especially in diabetes, in which AGEs form rapidly.

Revised Cardiac Risk Index versus ASA Status as a Predictor for Noncardiac Events After Posterior Lumbar Decompression

BACKGROUND

The Revised Cardiac Risk Index (RCRI) was designed to predict risk for cardiac events after noncardiac surgery. However, there is a paucity of literature that directly addresses the relationship between RCRI and noncardiac outcomes after posterior lumbar decompression (PLD). The objective of this study is to determine the ability of RCRI to predict noncardiac adverse events after PLD.

METHODS

The American College of Surgeons National Surgical Quality Improvement Program was used to identify patients undergoing PLD from 2006 to 2014. Multivariate and receiver operating characteristic analysis was used to identify associations between RCRI and postoperative complications.

RESULTS

A total of 52,066 patients met the inclusion criteria. Membership in the RCRI=1 cohort independently predicted unplanned intubation, ventilation >48 hours, progressive renal insufficiency, acute renal failure, urinary tract infection (UTI), sepsis, septic shock, and readmission. Membership in the RCRI=2 cohort independently predicted for superficial surgical site infection, pneumonia, unplanned intubation, ventilation >48 hours, bleeding transfusion, progressive renal insufficiency, acute renal failure, UTI, sepsis, septic shock, and readmission. Membership in the RCRI=3 cohort independently predicted unplanned intubation (odds ratio [OR], 11.8), ventilation >48 hours (OR, 23.0), acute renal failure (OR, 84.5), and UTI (OR, 3.6). RCRI had a poor discriminative ability (DA) (area under the curve = 0.623), and American Society of Anesthesiologists status had a fair DA (area under the curve = 0.770) to predict a composite of noncardiac complications.

CONCLUSIONS

RCRI was predictive of a wide range of noncardiac complications after PLD but had a diminished DA to predict a composite of any noncardiac complication than did American Society of Anesthesiologists score. Consideration of the RCRI as a component of preoperative surgical risk stratification can minimize patient morbidity and mortality after lumbar decompression.

Diabetes Mellitus as a Risk Factor for Acute Postoperative Complications Following Elective Adult Spinal Deformity Surgery

STUDY DESIGN

Retrospective cohort study.

OBJECTIVES

Diabetes mellitus is a highly prevalent disease in the United States. Adult spinal deformity (ASD) surgery encompasses a wide variety of spinal disorders and is associated with a morbidity rate between 20% and 80%. Considering utilization of spinal surgery will continue to increase, this study investigates the influence of diabetes mellitus on acute postoperative outcomes following elective ASD surgery.

METHODS

The 2010-2014 American College of Surgeon's National Surgical Quality Improvement Program database was queried using Current Procedural Terminology and International Classification of Diseases (9th Revision) diagnosis codes relevant to ASD surgery. Patients were divided into cohorts based on their diabetic status. Bivariate and multivariate logistic regression analyses were employed to identify which 30-day postoperative outcomes patients are at risk for.

RESULTS

A total of 5809 patients met the inclusion criteria for the study of which 4553 (84.2%) patients were nondiabetic, 578 (10.7%) patients had non-insulin-dependent diabetes mellitus (NIDDM), and 275 (5.1%) patients had insulin-dependent diabetes mellitus (IDDM). Diabetes status was significantly associated with length of stay ≥5 days (NIDDM: odds ratio [OR] = 1.27, 95% confidence interval [CI] = 1.02-1.58, P = .034; IDDM: OR = 1.55, 95% CI = 1.15-2.09, P = .004), any complication (NIDDM: OR = 1.26, 95% CI = 1.01-1.58, P = .037), urinary tract infection (NIDDM: OR = 1.87, 95% CI = 1.14-3.05, P = .012), and cardiac complications (IDDM: OR = 4.05, 95% CI = 1.72-9.51, P = .001).

CONCLUSIONS

Given the prevalence of diabetes, surgeons will invariably encounter these patients for ASD surgery. The present study identifies the increased risk NIDDM and IDDM patients experience following ASD surgery. Quantification of this increased risk may improve the selection of appropriate surgical candidates, patient risk stratification, and patient postoperative safety.

Poorer Fusion Outcomes in Diabetic Cervical Spondylotic Myelopathy Patients Undergoing Single-level Anterior Cervical Discectomy and Fusion Does Not Compromise Functional Outcomes and Quality of Life

STUDY DESIGN

Retrospective matched pair cohort study using prospectively collected registry data.

OBJECTIVES

The aim of this study was to determine whether patients with DM have poorer patient-reported outcomes and poorer fusion rates after undergoing a single-level anterior cervical discectomy and fusion (ACDF) for cervical myelopathy.

SUMMARY OF BACKGROUND DATA

ACDF remains the most common procedure in the treatment of cervical spondylotic myelopathy (CSM); however, there is a paucity of literature with regards to patient-reported outcome measures (PROMs), health-related quality-of-life (HRQOL) scores, and fusion rates post-ACDF in diabetic patients with CSM.

METHODS

From 2002 to 2012, 29 diabetic patients were matched with 29 nondiabetic controls. Patient demographics, perioperative data, and validated spine-specific scores including the Numerical Pain Rating Scale on Neck Pain and Upper Limb Pain, American Academy of Orthopaedic Surgeons (AAOS) neck pain and disability scores, AAOS Neurogenic Symptoms Score, Neck Disability Index, Japanese Orthopaedic Association Cervical Myelopathy Score, and Short Form 36 Physical/Mental Component Summaries were recorded. Fusion rates based on Bridwell grading were assessed at 2 years.

RESULTS

After matching, there were no significant preoperative differences in patient demographics, clinical outcomes, PROMs or HRQoL measures between the DM and control group (P > 0.05). There was no difference in either length of hospital stay (P = 0.92) or length of surgery (P = 0.92) between the two groups. At 2 years postoperatively, there were no significant differences between validated spine-specific scores, PROMs, HRQoL scores, satisfaction rates, or fulfilment of expectations between the two groups. Significant poorer Bridwell fusion grades were noted in the DM group at 2 years postoperatively (P < 0.05). Subgroup analysis within the DM group demonstrated that glycated hemoglobin levels had no impact on functional outcomes, fulfilment of expectations, or patient satisfaction at 2 years (P > 0.05).

CONCLUSION

Despite poorer fusion outcomes following single-level ACDF for symptomatic CSM, there was no significant difference in validated spine outcome scores, PROMs, HRQoL measures, or satisfaction levels when compared to nondiabetic controls at short-term follow-up.

LEVEL OF EVIDENCE

3.

Patient Factors Contributing to Prolonged Postoperative Length of Stay and Increased Rate of Readmission After Elective Posterior Cervical Fusion

STUDY DESIGN

This is retrospective study of prospectively collected data.

OBJECTIVE

To identify patient factors that are independently associated with prolonged length of stay (LOS) and readmission after posterior cervical fusion (PCF) utilizing a large national database.

SUMMARY OF BACKGROUND DATA

A number of studies have investigated the morbidity and mortality after PCF; however, little is known about the factors that are associated with prolonged LOS and readmission, both of which incur increased costs for patients and hospitals.

METHODS

The American College of Surgeons National Surgical Quality Improvement Program database was queried from 2011 to 2014. Current Procedural Terminology code 22600 was used to identify patients who underwent PCF. All patient factors were assessed for association with LOS and readmission rate using bivariate and multivariate logistic regressions.

RESULTS

A total of 2667 patients who underwent PCF met the inclusion criteria for LOS analysis. Average (±SD) LOS was 3.92 (±3.24) days, and median LOS was 3 days (interquartile range, 2-5 d). On multivariate analysis, increased LOS was found to be significantly associated with dependent functional status (P<0.001), diabetes mellitus (P=0.021), preoperative anemia (P=0.001), American Society of Anesthesiologists class 3 or 4 (P<0.001), and number of fused levels (P<0.001). A total of 2591 patients met criteria (LOS≤11 d) for analysis of readmission. Readmission rate among these patients was 7.1%. Average (±SD) LOS of the patients not readmitted within 30 days of operation was 3.89 (±3.25), whereas the average (±SD) LOS of the patients readmitted was 4.24 (±3.08). On multivariate analysis, readmission was found to be significantly associated with only dependent functional status (P=0.019) and increased number of fused levels (P=0.032).

CONCLUSIONS

The current study provides valuable information on patient factors that are associated with prolonged LOS and readmission, which would be useful in enhanced informed consent before surgery, surgical planning, discharge planning, and optimizing postoperative care.

LEVEL OF EVIDENCE

Level III.

Impact of Glycemic Control on Morbidity and Mortality in Adult Idiopathic Scoliosis Patients Undergoing Spinal Fusion

STUDY DESIGN

This is a retrospective analysis of administrative database.

OBJECTIVE

To elucidate the effect of glycemic control on surgical outcomes of middle-aged and elderly idiopathic scoliosis patients undergoing spinal fusion surgery.

SUMMARY OF BACKGROUND DATA

Diabetes mellitus (DM) is a condition thought to adversely affect outcomes of spine surgery. However, no study has stratified glycemic control levels and their impact on outcome for idiopathic scoliosis patients receiving a spinal fusion surgery. Previous studies may have reported higher than true rates of complications for controlled diabetic patients, who are the majority of diabetic patients.

MATERIALS AND METHODS

The Nationwide Inpatient Sample was queried from years 2002 to 2011. We extracted idiopathic scoliosis patients older than 45 years of age that received spinal fusion and analyzed complications and outcomes variables among 3 cohorts: nondiabetic patients, controlled diabetics, and uncontrolled diabetics. Multivariate analyses were used to assess whether glycemic control was a risk factor for adverse postoperative outcomes.

RESULTS

Controlled diabetics had significantly increased rates of acute renal failure (ARF), while uncontrolled diabetics had significantly increased rates of acute postoperative hemorrhage. In multivariate analyses controlling for patient factors and comorbidities, controlled DM was found to be an independent predictor of ARF [odds ratio (OR), 1.863; 95% confidence interval (CI), 1.346-2.579; P=0.0002), and uncontrolled DM was found to be a significant risk factor for acute postoperative hemorrhage (OR, 2.182; 95% CI, 1.192-3.997; P=0.0115), ARF (OR, 4.839; 95% CI, 1.748-13.392; P=0.0024), deep vein thrombosis (OR, 5.825; 95% CI, 1.329-25.522, P=0.0194) and in-patient mortality (OR, 8.889; 95% CI, 1.001-78.945; P=0.0499).

CONCLUSIONS

Controlled DM was found to be a risk factor for ARF in adult idiopathic scoliosis patients undergoing spinal fusion surgery, while uncontrolled DM was shown to be a risk factor for postoperative hemorrhage, ARF, deep vein thrombosis, and mortality. The present study provides valuable data for better informed consent for patients with diabetes considering surgery for idiopathic scoliosis.

LEVEL OF EVIDENCE

Level III.

Predominantly negative impact of diabetes on spinal surgery: A review and recommendation for better preoperative screening

BACKGROUND

For patients undergoing spine surgery, the literature attributes significant increased perioperative risks/adverse events (AE) complications, longer length of stay (LOS), and higher 30-day readmission/reoperation rates to those with diabetes. Diabetics are often divided into those with insulin dependent diabetes (IDDM), and non-insulin dependent diabetes (NIDD). However, other series also compare those with uncontrolled diabetes (UCDM) vs. those with controlled DM (CDM).

METHODS

We found a marked variation in the size and quality of studies identified in PubMed regarding the impact of diabetes on spinal surgery (e.g., focusing on complications, AE, outcomes, morbidity, and mortality).

RESULTS

Of the 197,461 lumbar fusions in one NIS (Nationwide Inpatient Sample 1988-2003), 11,000 (5.6%) diabetics (DM) had higher infection rates, transfusion rates, more pneumonias, higher in-hospital mortality rates, greater costs, and longer LOS than those undergoing similar procedures without DM. For 3726 ACS-NSQIP patients undergoing anterior cervical fusions, 270 NIDDM had more urinary tract infections and returns to the operating room; the 171 IDDM required more reoperations, 30 day readmission, and longer LOS (by 5 days) vs. 3285 non DM. Of the 5627 patients undergoing posterior cervical fusions (ACS-NSQIP), 2029 (36.1%) had AE directly related to DM. In another NSQUIP study of 51277 patients undergoing lumbar spine surgery, IDDM and NIDDM demonstrated longer LOS, plus IDDM showed more surgical AE and 30 day readmissions vs. those with no DM.

CONCLUSIONS

Patients with IDDM or NIDDM undergoing spine surgery exhibited more perioperative complications/AE/morbidity, longer LOS, and higher readmission/reoperation rates vs. non DM.

Predictors of extended length of stay, discharge to inpatient rehab, and hospital readmission following elective lumbar spine surgery: introduction of the Carolina-Semmes Grading Scale

OBJECTIVE Extended hospital length of stay (LOS), unplanned hospital readmission, and need for inpatient rehabilitation after elective spine surgery contribute significantly to the variation in surgical health care costs. As novel payment models shift the risk of cost overruns from payers to providers, understanding patient-level risk of LOS, readmission, and inpatient rehabilitation is critical. The authors set out to develop a grading scale that effectively stratifies risk of these costly events after elective surgery for degenerative lumbar pathologies. METHODS The Quality and Outcomes Database (QOD) registry prospectively enrolls patients undergoing surgery for degenerative lumbar spine disease. This registry was queried for patients who had undergone elective 1- to 3-level lumbar surgery for degenerative spine pathology. The association between preoperative patient variables and extended postoperative hospital LOS (LOS ≥ 7 days), discharge status (inpatient facility vs home), and 90-day hospital readmission was assessed using stepwise multivariate logistic regression. The Carolina-Semmes grading scale was constructed using the independent predictors for LOS (0-12 points), discharge to inpatient facility (0-18 points), and 90-day readmission (0-6 points), and its performance was assessed using the QOD data set. The performance of the grading scale was then confirmed separately after using it in 2 separate neurosurgery practice sites (Carolina Neurosurgery & Spine Associates [CNSA] and Semmes Murphey Clinic). RESULTS A total of 6921 patients were analyzed. Overall, 290 (4.2%) patients required extended LOS, 654 (9.4%) required inpatient facility care/rehabilitation on hospital discharge, and 474 (6.8%) were readmitted to the hospital within 90 days postdischarge. Variables that remained as independently associated with these unplanned events in multivariate analysis included age ≥ 70 years, American Society of Anesthesiologists Physical Classification System class > III, Oswestry Disability Index score ≥ 70, diabetes, Medicare/Medicaid, nonindependent ambulation, and fusion. Increasing point totals in the Carolina-Semmes scale effectively stratified the incidence of extended LOS, discharge to facility, and readmission in a stepwise fashion in both the aggregate QOD data set and when subsequently applied to the CNSA/Semmes Murphey practice groups. CONCLUSIONS The authors introduce the Carolina-Semmes grading scale that effectively stratifies the risk of prolonged hospital stay, need for postdischarge inpatient facility care, and 90-day hospital readmission for patients undergoing first-time elective 1- to 3-level degenerative lumbar spine surgery. This grading scale may be helpful in identifying patients who may require additional resource utilization within a global period after surgery.

Diabetes as an Independent Predictor for Extended Length of Hospital Stay and Increased Adverse Post-Operative Events in Patients Treated Surgically for Cervical Spondylotic Myelopathy

BACKGROUND

Diabetes as an independent driver of peri-operative outcomes, and whether its severity impacts indications is conflicted in the research. The purpose of this study is to evaluate diabetes as a predictor for postoperative outcomes in cervical spondylotic myelopathy (CSM) patients.

METHODS

A retrospective review was performed of patients treated surgically for CSM (ICD-9 721.1) from 2010-2012 in the prospectively-collected American College of Surgeons National Surgical Quality Improvement Program (NSQIP) database. Outcome measures were length of stay, and the presence of complications. Diabetic patients were stratified based on whether or not their diabetes was insulin- or non-insulin-dependent.

RESULTS

A total of 5,904 surgical CSM patients were included, 1101 (19%) had diabetes. 722 (65%) were non-insulin-dependent diabetics, and 381 (35%) were insulin-dependent diabetics. Diabetes was found to be an independent predictor of extended LOS (OR: 1.878[2.262-1.559], p<0.001) as well as of developing a complication (OR: 1.666[2.217-1.253], p<0.001) after controlling for associated variables like BMI. Type of diabetes (insulin- vs. non-insulin-dependent) showed little significant difference between the groups (p>0.05), however, patients with insulin-dependent diabetes were associated with an increased incidence of wound complications (p=0.027); severity of diabetes was not associated with any other individual complications.

CONCLUSIONS

Type and severity of diabetes is not a predictor for complication. Diabetes is associated with extended LOS and peri-operative morbidity. Level of evidence: Class 2b. Clinical relevance: Our findings support the view of many spine surgeons, who believe that diabetes has a negative impact on the outcome of surgery for CSM. Our findings support those cohort studies that found an association between diabetes and worst post-operative outcomes following surgical treatment of CSM. These findings lend support to the importance of monitoring preoperative serum glucose levels, as prevention of peri-operative hyperglycemia has been linked to improved postoperative outcomes in spine, joint and colon surgery.

Risk Factors for 30-Day Unplanned Readmission and Major Perioperative Complications After Spine Fusion Surgery in Adults: A Review of the National Surgical Quality Improvement Program Database

STUDY DESIGN

Retrospective review of a prospective cohort.

OBJECTIVE

The aim of the study was to determine the patient characteristics and surgical procedure factors related to increased rates of 30-day unplanned readmission and major perioperative complications after spinal fusion surgery, and the association between unplanned readmission and major complications.

SUMMARY OF BACKGROUND DATA

Reducing unplanned readmissions can reduce the cost of healthcare. Payers are implementing penalties for 30-day readmissions after discharge. There is limited data regarding the current rates and risk factors for unplanned readmission and major complications related to spinal fusion surgery.

METHODS

Spine fusion patients were identified using the 2012 and 2013 American College of Surgeons National Surgical Quality Improvement Program Participant User File. Rates of readmissions within 30 days after spine fusion surgery were calculated using the person-years method. Cox proportional hazards models were used to assess the independent associations of spine surgical procedure types, diagnoses, patient profiles, and major perioperative complications with unplanned related readmissions. Independent risk factors for major complications were assessed by multivariable logistic regression.

RESULTS

Of the 18,602 identified patients, there was a 5.2% overall major perioperative complication rate. There was a rate of 4.4% per 30 person-days for unplanned readmissions related to index surgery. Independent risk factors for both readmissions and major perioperative complications included combined anterior and posterior surgery, diagnosis of solitary tumor, older age, and higher American Society of Anesthesiologists class. Patients with deep/organ surgical site infection carried higher risk of having unplanned readmission, followed by pulmonary embolism, acute renal failure, and stroke/cerebral vascular accident with neurological deficit.

CONCLUSION

This study provides benchmark rates of 30-day readmission based on diagnosis and procedure codes from a high-quality database for adult spinal fusion patients and showed increased rates of 30-day unplanned readmission and major perioperative complications for patients with specific risk factors. Targeted preoperative planning on modifiable risk factors with proportional reimbursement may promote higher-quality healthcare.

LEVEL OF EVIDENCE

3.

Incidence and Risk Factors for Prolonged Hospitalization and Readmission after Transsphenoidal Pituitary Surgery

Objective

To evaluate the incidence and factors associated with 30-day readmission and to analyze risk factors for prolonged hospital length of stay following transsphenoidal pituitary surgery.

Study Design

Retrospective longitudinal claims analysis.

Setting

American College of Surgeons National Surgical Quality Improvement Program.

Subjects and Methods

The database of the American College of Surgeons National Surgical Quality Improvement Program was queried for patients who underwent transsphenoidal pituitary surgery ( Current Procedural Terminology code 61548 or 62165) between 2005 and 2014. Patient demographic information, indications for surgery, and incidence of hospital readmission and length of stay were reviewed. Risk factors for readmission and prolonged length of stay, defined as >75th percentile for the cohort, were identified through logistic regression modeling.

Results

A total of 1006 patients were included for analysis. Mean hospital length of stay after surgery was 4.1 ± 0.2 days. Predictors of prolonged length of stay were operative time ( P < .001, odds ratio [OR] = 1.7, 95% confidence interval [95% CI] = 1.5-2.0), bleeding disorder ( P = .049, OR = 3.1, 95% CI = 1.0-9.5), insulin-dependent diabetes ( P = .007, OR = 2.4, 95% CI = 1.3-4.4), and reoperation ( P < .001, OR = 10.3, 95% CI = 4.7-23.9). In a subset analysis of 529 patients who had surgery between 2012 and 2014, 7.2% (n = 38) required hospital readmission. History of congestive heart failure (CHF) was a predictor of hospital readmission ( P = 0.03, OR = 12.7, 95% CI = 1.1-144.0).

Conclusion

This review of a large validated surgical database demonstrates that CHF is an independent predictor of hospital readmission after transsphenoidal surgery. Although CHF is a known risk factor for postoperative complications, it poses unique challenges to patients with potential postoperative pituitary dysfunction.

Impact of Insulin Dependence on Lumbar Surgery Outcomes: An NSQIP Analysis of 51,277 Patients

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

The objective of our study was to evaluate the differential impact of insulin dependence on lumbar surgery outcomes, including surgical and medical complications, total length of hospital stay, nonhome bound discharge, and unplanned readmissions.

SUMMARY OF BACKGROUND DATA

Although the negative effects of diabetes mellitus (DM) on joint arthroplasty outcomes are well documented, there is a paucity of studies evaluating those on spine surgery.

METHODS

Data files from 2005 to 2013 were reviewed and to collect data on patients undergoing lumbar spine surgery. χ tests, for categorical variables, and one-way ANOVA, for continuous variables, were used to identify differences in perioperative variables among patients who do not have DM, who are insulin-independent (NIDDM), and who are insulin-dependent (IDDM). Binary logistic regression analysis assessed the effect of DM status on surgical outcomes. Significance was defined as P < 0.05.

RESULTS

Significant differences were detected among the three groups in surgical and medical complication and unplanned readmission rates, as well as rates of nonhome-bound discharge. The NIDDM and IDDM groups experienced significantly longer mean total hospital length of stay at 3.2 and 3.9 days, respectively, compared with 2.6 days for nondiabetics (P < 0.0001). Both NIDDM (OR, 1.226; P = 0.017) and IDDM (OR, 1.499; P < 0.0001) independently increased the risk for medical complications, whereas only IDDM (OR, 2.429; P < 0.0001) was associated with surgical complications. IDDM was found to be associated with increased rate of 30-day unplanned readmission (OR, 1.353; P = 0.005). Neither NIDDM nor IDDM had an effect on the likelihood of nonhome discharge.

CONCLUSION

We hope our findings improve risk stratification efforts and informed consent for two DM patient populations. In addition, our findings advocate for appropriate risk stratification of a subgroup DM patients who are dependent on insulin and are at greater risk for surgical morbidity.

LEVEL OF EVIDENCE

3.

Osteoporosis in Cervical Spine Surgery

STUDY DESIGN

Retrospective administrative database analysis.

OBJECTIVE

To investigate the effect of osteoporosis (OS) on complications and outcomes in patients undergoing cervical spine surgery.

SUMMARY OF BACKGROUND DATA

OS is the most prevalent degenerative human bone disease, and spine surgeons will inevitably perform procedures on patients with OS. These patients might present a difficult patient cohort because many fixation techniques depend on bone quality and adequate bone healing--both of which are compromised in OS.

METHODS

The nationwide inpatient sample was queried using the Ninth Revision, Clinical Modification procedural codes for cervical spine procedures and diagnosis codes for degenerative conditions of cervical spine from 2002 to 2011. Patients were separated into two cohorts, those patients with OS and those without OS. Demographics, hospital characteristics, and adjusted complication likelihood were analyzed. Multivariate regression analysis was performed to determine odds of revision surgery in patients with OS.

RESULTS

Of all patients undergoing degenerative cervical spine surgery, 2% were identified as having OS (32,557 of a sample of 1,602,129 patients). Osteoporotic patients were more likely to undergo posterior cervical spine fusion when compared with those patients without OS (11.3% vs. 5.4%, P < 0.0001). Moreover, circumferential fusion was performed 3 times more frequently in the osteoporotic cohort. Adjusted complications showed increased odds for postoperative hemorrhage (odds ratio = 1.70, 95% confidence interval = 1.46-1.98, P < 0.0001). Patients with OS stayed in the hospital longer (3.5 vs. 2.5 days, P < 0.0001) and had 30% costlier hospitalizations. Multivariate for revision surgery indicated that osteoporotic patients had significantly increased odds of revision surgery (odds ratio = 1.54, P ≤ 0.0001) when referenced to non-osteoporotic patients undergoing cervical spine surgery.

CONCLUSION

Osteoporotic patients were more likely to undergo revision surgery, have longer hospitalizations, and have higher hospitalization costs, than their non-osteoporotic counterparts.

LEVEL OF EVIDENCE

3.

Risk Modeling Predicts Complication Rates for Spinal Surgery

STUDY DESIGN

Retrospective review of clinical data registry.

OBJECTIVE

In the current era of quality reporting and pay for performance, neurosurgeons must develop models to identify patients at high risk of complications. We sought to identify risk factors for complications in spine surgery and to develop a score predictive of complications.

SUMMARY OF BACKGROUND DATA

We examined spinal surgeries from the American College of Surgeons National Surgical Quality Improvement Project (ACS-NSQIP) database. 22,430 cases were identified based on common procedural terminology.

METHODS

Univariate analysis followed by multivariate regression was used to identify significant factors.

RESULTS

The overall complication rate for the cohort was 9.9%. The most common complications were postoperative bleeding requiring transfusion (4.1%), nonwound infections (3.1%), and wound-related infections (2.2%). Multivariate regression analysis identified 20 factors associated with complications. Assigning 1 point for the presence of each factor a risk model was developed. The range of scores for the cohort was 0 to 13 with a median score of 4. Complication rates for a risk score of 0 to 4 was 3.7% and for scores 5 to 13 was 18.5%. The risk model robustly predicted complication rates, with complication rate of 1.2% for score of 0 (n = 412, 1.8% of total) and 63.6% and 100% for scores of 12 and 13 (n = 22 patients, 0.1% of total cohort) respectively (P < 0.001). The risk score also correlated strongly with total length of stay, mortality, and total work relative value units for the case.

CONCLUSION

Patient-specific risk factors including comorbidities are strongly associated with surgical complications, length of stay, cost of care, and mortality in spine surgery and can be used to develop risk models that are highly predictive of complications.

LEVEL OF EVIDENCE

3.