Does patient selection account for the perceived cost savings in outpatient spine surgery? A meta-analysis of current evidence and analysis from an administrative database

OBJECTIVEFrom 1994 to 2006 outpatient spinal surgery increased 5-fold. The perceived cost savings with outcomes comparable to or better than those achieved with inpatient admission for the same procedures are desirable in an era where health expenditures are scrutinized. The increase in outpatient spine surgery is also driven by the proliferation of ambulatory surgery centers. In this study, the authors hypothesized that the total savings in outpatient spine surgery is largely driven by patient selection and biases toward healthier patients.METHODSA meta-analysis assessed patient selection factors and outcomes associated with outpatient spine procedures. Pooled odds ratios and mean differences were calculated using a Bayesian random-effects model. The authors extended this analysis in a novel way by using the results of the meta-analysis to examine cost data from an administrative database of academically affiliated hospitals. A Bayesian approach with priors informed by the meta-analysis was used to compare costs for inpatient and outpatient performance of anterior cervical discectomy and fusion (ACDF) and lumbar laminectomy.RESULTSSixteen studies with a total of 370,195 patients met the inclusion criteria. Outpatient procedures were associated with younger patient age (mean difference [MD] -2.34, 95% credible interval [CrI] -4.39 to -0.34) and no diabetes diagnosis (odds ratio [OR] 0.78, 95% CrI 0.54-0.97). Outpatient procedures were associated with a lower likelihood of reoperation (OR 0.42, 95% CrI 0.16-0.80), 30-day readmission (OR 0.39, 95% CrI 0.16-0.74), and complications (OR 0.29, 95% CrI 0.15-0.50) and with lower overall costs (MD -$121,392.72, 95% CrI -$216,824.81 to -$23,632.92). Additional analysis of the national administrative data revealed more modest cost savings than those found in the meta-analysis for outpatient spine surgeries relative to inpatient spine surgeries. Estimated cost savings for both younger patients ($555 for those age 30-35 years [95% CrI -$733 to -$374]) and older patients ($7290 for those age 65-70 years [95% CrI -$7380 to -$7190]) were less than the overall cost savings found in the meta-analysis.CONCLUSIONSCompared to inpatient spine surgery, outpatient spine surgery was associated with better short-term outcomes and an initial reduction in direct costs. A selection bias for outpatient procedures toward younger, healthier patients may confound these results. The additional analysis of the national database suggests that cost savings in the outpatient setting may be less than previously reported and a result of outpatient procedures being offered more frequently to younger and healthier individuals.

Enterobacter Infection after Spine Surgery: An Institutional Experience

BACKGROUND

Gram-negative surgical site infections (SSI) following spine surgery are becoming increasingly more common owing to a broad perioperative antibiotic usage targeting gram-positive organisms. Enterobacter species have been reported to be the most common gram-negative bacteria following spine surgery.

METHODS

We queried our institutional database for Enterobacter SSIs after spine surgery at a single institution from 2009-2016. Relevant demographic, clinical, and operative variables were collected. We compared this cohort to patients who had non-Enterobacter SSI during the same period.

RESULTS

Enterobacter species were isolated in 16 patients (9 males) diagnosed with SSI after undergoing spine surgery. This group represented 0.2% of all spine cases and 14.5% of all spinal SSIs. Seven patients (43.8%) required multiple irrigations and debridements (I&Ds) (range: 2-8), whereas only 17 of 94 patients (18.1%) with non-Enterobacter SSI required multiple I&Ds (range: 2-5, P = 0.043). Those infected with Enterobacter were associated with higher BMI (37.6 ± 12.7 vs. 31.7 ± 8, P = 0.036), earlier wound dehiscence (14.8 vs. 24.6 days, P = 0.01), polymicrobial infections (37.5% vs. 10.6%, P = 0.012), and longer length of stay (18 days [9.5-31.5] vs. 5 days [3-8], P = 0.01) when compared to non-Enterobacter SSI cohort. At an average of 24.2 months follow-up, all 15 surviving patients were infection free with no further revision surgeries needed.

CONCLUSIONS

Enterobacter SSI cases were associated with higher BMI, earlier wound breakdown, polymicrobial infection and longer length of stay. Nevertheless, with vigilant surveillance and timely I&Ds, these challenging infections can be treated successfully with original implant retention in almost all cases.

Operative Approaches for Lumbar Disc Herniation: A Systematic Review and Multiple Treatment Meta-Analysis of Conventional and Minimally Invasive Surgeries

BACKGROUND

Minimally invasive surgery (MIS) techniques have emerged as viable and safe alternatives for lumbar disc herniation, including percutaneous discectomy, percutaneous endoscopic discectomy, and tubulardiscectomy (TD). We present here a systematic review and a multiple-treatment meta-analysis evaluating the operative outcomes and patient-reported outcomes of open/microdiscectomy (OD/MD) and all MIS approaches for lumbar disc herniation.

METHODS

The PICO approach and PRISMA (i.e., Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines were followed to query existing online databases since their inception to 2016, which yielded 14 studies after we applied the inclusion/exclusion criteria. The Cochrane Collaboration's tool for assessing risk of bias in randomized trials was used to assess the risk of bias in each study was used to assess the risk of bias in each study. Each outcome was assessed across all studies with the GRADE (i.e., Grading of Recommendations, Assessment, Development and Evaluations) criteria.

RESULTS

There were 1707 patients analyzed, with 782 (45.81%) undergoing OD/MD, 491 (28.76%) undergoing TD, 199 (11.65%) undergoing percutaneous endoscopic discectomy, and 235 (13.76%) patients undergoing percutaneous discectomy. TD was found to be associated with significantly worse Oswestry Disability Index scores (mean difference 1.17, P = 0.03) whereas OD/MD was associated with worse Oswestry Disability Index scores compared with all other approaches (mean difference 2.61, P = 0.03), significantly longer duration of stay (mean difference 2.96, P = 0.04), and more blood loss (mean difference 30.53, P < 0.001). In terms of complications, TD was found to be associated with a greater rate of overall complications (odds ratio [OR] 1.49, P = 0.002), greater incidence of dural tears (OR 1.72 P = 0.04), and recurrent herniation (OR 2.09, P = 0.0007). Finally, OD/MD was associated with significantly lower incidence of revision surgery (OR 0.53, P = 0.0007).

CONCLUSIONS

Our meta-analysis revealed that tubular-discectomy and percutaneous-endoscopic-discectomy, the most commonly employed MIS techniques for discectomy, can be used as safe alternatives for open discectomy depending on the preference of the operating surgeon.

Skull base plasmacytoma: A unique case of POEMS syndrome with a plasmacytoma causing craniocervical instability

INTRODUCTION

Plasmacytomas, considered to be the solitary counterparts of multiple myeloma, are neoplastic monoclonal plasma cell proliferations within soft tissue or bone. Plasmacytomas often present as a collection of findings known as POEMS-syndrome (Polyneuropathy, Organomegaly, Endocrinopathy, M-Protein spike, and Skin changes).

CASE DESCRIPTION

We present a report of a 47 yo male diagnosed with POEMS-syndrome secondary to a skull base plasmacytoma. The mass resulted in marked instability of the cranio-cervical junction due to bony erosion. Following an induction course of chemotherapy, he showed clinical improvement with a marked reduction in tumor size and underwent an autologous peripheral blood stem cell transplant for systemic treatment of his POEMS-syndrome. Following completion of systemic treatment, he then underwent a definitive occipital-cervical fusion without complications. His neurologic exam upon dismissal was stable with subjective improvement in left upper extremity strength. Postoperative radiographs confirmed spinal alignment and pathological examination of a small biopsy from C1 revealed benign fibrous tissue.

CONCLUSION

To the best of our knowledge, this is the first report of a skull-base plasmacytoma associated with POEMS-syndrome, causing cranio-cervical instability. The approach of systemic therapy combined with temporary external fixation, followed by definitive occipital cervical fusion resulted in a good outcome for this patient.

Management of major vascular injury during pedicle screw instrumentation of thoracolumbar spine

OBJECTIVES

Vascular injury is a rare complication of spinal instrumentation. Presentation can vary from immediate hemorrhage to pseudoaneurysm formation. In the literature, surgical approach to repair has varied based on anatomy, acuity of diagnosis, infection, and available technology. In this manuscript, we aim to describe our institutional experience with vascular injuries in thoraco-lumbar spine surgery.

PATIENTS AND METHODS

We report our institutional experience of three cases of vascular injury secondary to pedicle screw misplacement and their management, as well as a review of the literature.

RESULTS

The first case had a history of previous instrumentation and presented with back pain and fever. The patient was taken for instrumentation exploration via a posterior approach. Aortic violation was discovered at T6 intraoperatively during instrumentation removal and the patient underwent emergent endovascular repair. The second case presented with chronic back pain after multiple prior posterior fusions and CT angiogram showing screw perforation on the aorta at T10. The patient underwent elective endovascular repair with synchronous removal of the instrumentation. The third case presented with radicular leg pain 6 months after L4-S1 posterior lumbar interbody fusion, with CT scan demonstrating the left S1 screw abutting the L5 nerve root and common iliac vein. The patient underwent elective instrumentation revision with intraoperative venography.

CONCLUSION

Major vascular injury is a known complication of spinal surgery, especially if it involves instrumentation with pedicle screws. Treatment approach has evolved with the advancement of endovascular technology; however, open surgery remains an option when anatomy or infection is prohibitive. In the elective setting, preoperative planning with attention to surgical approach, positioning, and contingencies, should occur in a multidisciplinary fashion. Repair with an aortic stent-graft cuff may minimize unnecessary coverage of the descending thoracic aorta and intercostal arteries.

Allegations of Failure to Obtain Informed Consent in Spinal Surgery Medical Malpractice Claims

Importance

Predictive factors associated with increased risk of medical malpractice litigation have been identified, including severity of injury, physician sex, and error in diagnosis. However, there is a paucity of literature investigating informed consent in spinal surgery malpractice.

Objective

To investigate the failure to obtain informed consent as an allegation in medical malpractice claims for patients undergoing a spinal procedure.

Design, Setting, and Participants

In this retrospective cohort study, a national medicolegal database was searched for malpractice claim cases related to spinal surgery for all years available (ie, January 1, 1980, through December 31, 2015).

Main Outcomes and Measures

Failure to obtain informed consent and associated medical malpractice case verdict.

Results

A total of 233 patients (117 [50.4%] male and 116 [49.8%] female; 80 with no informed consent allegation and 153 who cited lack of informed consent) who underwent spinal surgery and filed a malpractice claim were studied (mean [SD] age, 47.1 [13.1] years in the total group, 45.8 [12.9] years in the control group, and 47.9 [13.3] years in the informed consent group). Median interval between year of surgery and year of verdict was 5.4 years (interquartile range, 4-7 years). The most common informed consent allegations were failure to explain risks and adverse effects of surgery (52 [30.4%]) and failure to explain alternative treatment options (17 [9.9%]). In bivariate analysis, patients in the control group were more likely to require additional surgery (45 [56.3%] vs 53 [34.6%], P = .002) and have more permanent injuries compared with the informed consent group (46 [57.5%] vs 63 [42.0%], P = .03). On multivariable regression analysis, permanent injuries were more often associated with indemnity payment after a plaintiff verdict (odds ratio [OR], 3.12; 95% CI, 1.46-6.65; P = .003) or a settlement (OR, 6.26; 95% CI, 1.06-36.70; P = .04). Informed consent allegations were significantly associated with less severe (temporary or emotional) injury (OR, 0.52; 95% CI, 0.28-0.97; P = .04). In addition, allegations of informed consent were found to be predictive of a defense verdict vs a plaintiff ruling (OR, 0.41; 95% CI, 0.17-0.98; P = .046) or settlement (OR, 0.01; 95% CI, 0.001-0.15; P < .001).

Conclusions and Relevance

Lack of informed consent is an important cause of medical malpractice litigation. Although associated with a lower rate of indemnity payments, malpractice lawsuits, including informed consent allegations, still present a time, money, and reputation toll for physicians. The findings of this study can therefore help to improve preoperative discussions to protect spinal surgeons from malpractice claims and ensure that patients are better informed.

Full-endoscopic versus micro-endoscopic and open discectomy: A systematic review and meta-analysis of outcomes and complications

OBJECTIVES

The purpose of this study was to systematically compare the effectiveness and safety of full-endoscopic discectomy (FED) and micro-endoscopic discectomy (MED) with open discectomy (OD) for the treatment of symptomatic lumbar disc herniation.

METHODS

Electronic searches were performed using six databases from their inception to February 2016, identifying all relevant randomized controlled trials and comparative observational studies comparing either FED or MED with OD. Data were extracted and analyzed according to predefined clinical endpoints.

RESULTS

Twenty three studies were selected for analysis, including 421 FED, 6914 MED, and 21,152 OD cases. No significant difference was found between FED and OD in regards to postoperative visual analog scale (VAS) leg pain scores (WMD 0.03, P=0.93). Similar results were obtained for MED vs OD (WMD 0.09, P=0.18). In terms of postoperative Oswestry disability index (ODI), both FED and MED were similar to OD (WMD -2.60, P=0.32 and WMD -1.00, P=0.21, respectively). FED had a significantly shorter operative duration compared to OD (54.6 vs 102.6min, P=0.0001). MED alone and endoscopic approaches overall (including MED and FED) demonstrated significantly lower estimated blood loss (44.3 vs 194.4mL, P=0.03 and 38.2 vs 203.5mL, respectively, both p<0.05). FED alone demonstrated a trend towards lower estimated blood loss in comparison to OD (3.3 vs 244.9mL, P=0.07). No difference was found in overall complications, recurrence or reoperation rates, dural tears, root injury, wound infections, and spondylodiscitis between FED vs OD, or MED vs OD.

CONCLUSIONS

Based on this meta-analysis, FED and MED appear to be safe and efficacious alternatives to traditional approaches, but these results require further investigation and validation by prospective randomized studies.

Risk factors for dural tears: a study of elective spine surgery. Neurol Res 2016;39:97-106. [PMID: 27908218 DOI: 10.1080/01616412.2016.1261236]

OBJECTIVE

This study moves beyond previous cohort studies and benchmark data by studying a population of elective spine surgery from a multicenter registry in an effort to validate, disprove, and/or identify novel risk factors for dural tears.

METHODS

A retrospective cohort analysis queried a multicenter registry for patients with degenerative spinal diagnoses undergoing elective spinal surgery from 2010-2014. Multivariable logistic regression analysis interrogated for independent risk factors of dural tears.

RESULTS

Of 104,930 patients, a dural tear requiring repair occurred in 0.6% of cases. On adjusted analysis, the following factors were independently associated with increased likelihood of a dural tear: ankylosing spondylitis vs. intervertebral disc disorders, greater than two levels, combined surgical approach and posterior approach vs. anterior approach, decompression only vs. fusion and decompression, age groups 85+, 75-84 and 65-74 vs. <65, obesity (BMI ≥30), corticosteroid use and preoperative platelet count <150,000.

CONCLUSIONS

This multicenter study identifies novel risk factors for dural tears in the elective spine surgery population, including corticosteroids, thrombocytopenia, and ankylosing spondylitis. The results of this analysis provide further information for surgeons to use both in operative planning and in preoperative counseling when discussing the risk of dural tears.

Micro vs. macrodiscectomy: Does use of the microscope reduce complication rates?

OBJECTIVE

A single level discectomy is one of the most common procedures performed by spine surgeons. While some practitioners utilize the microscope, others do not. We postulate improved visualization with an intraoperative microscope decreases complications and inferior outcomes.

METHODS

A multicenter surgical registry was utilized for this retrospective cohort analysis. Patients with degenerative spinal diagnoses undergoing elective single level discectomies from 2010 to 2014 were included. Univariate analysis was performed comparing demographics, patient characteristics, operative data, and outcomes for discectomies performed with and without a microscope. Multivariable logistic regression analysis was then applied to compare outcomes of micro- and macrodiscectomies.

RESULTS

Query of the registry yielded 23,583 patients meeting inclusion criteria. On univariate analysis the microscope was used in a greater proportion of the oldest age group as well as Hispanic white patients. Patients with any functional dependency, history of congestive heart failure, chronic corticosteroid use, or anemia (hematocrit<35%) also had greater proportions of microdiscectomies. Thoracic region discectomies more frequently involved use of the microscope than cervical or lumbar discectomies (25.0% vs. 16.4% and 13.0%, respectively, p<0.001). Median operative time (IQR) was increased in microscope cases [80min (60, 108) vs. 74min (54, 102), p<0.001]. Of the patients that required reoperation within 30days, 2.5% of them had undergone a microdiscectomy compared to 1.9% who had undergone a macrodiscectomy, p=0.044. On multivariable analysis, microdiscectomies were more likely to have an operative time in the top quartile of discectomy operative times, ≥103min (OR 1.256, 95% CI 1.151-1.371, p<0.001). In regards to other multivariable outcome models for any complication, surgical site infection, dural tears, reoperation, and readmission, no significant association with microdiscectomy was found.

CONCLUSIONS

The use of the microscope was found to significantly increase the odds of longer operative time, but not influence rates of postoperative complications. Thus, without evidence from this study that the microscope decreases complications, the use of the microscope should be at the surgeon's discretion, validating the use of both macro and micro approaches to discectomy as acceptable standards of care.

Synthesis and characterization of nanoparticle thin films of a-(PbSe)100-xCdx lead chalcogenides

We report the synthesis of amorphous (PbSe)100-xCdx (x = 5, 10, 15, and 20) nanoparticle thin films using thermal evaporation method under argon gas atmosphere. Thin films with a thickness of 20 nm have been deposited on glass substrates at room temperature under a continuous flow (50 sccm) of argon. X-ray diffraction patterns suggest the amorphous nature of these thin films. From the field emission scanning electron microscopy images, it is observed that these thin films contain quite spherical nanoparticles with an average diameter of approximately 20 nm. Raman spectra of these a-(PbSe)100-xCdx nanoparticles show a wavelength shift in the peak position as compared with earlier reported values on PbSe. This shift in peak position may be due to the addition of Cd in PbSe. The optical properties of these nanoparticles include the studies on photoluminescence and optical constants. On the basis of optical absorption measurements, a direct optical bandgap is observed, and the value of the bandgap decreases with the increase in metal (Cd) contents in PbSe. Both extinction coefficient (k) and refractive index (n) show an increasing trend with the increase in Cd concentration. On the basis of temperature dependence of direct current conductivity, the activation energy and pre-exponential factor of these thin films have been estimated. These calculated values of activation energy and pre-exponential factor suggest that the conduction is due to thermally assisted tunneling of the carriers.