Epidemiological trends in spine surgery over 10 years in a multicenter database

Risk Factors and Outcomes of Surgical Site Infections of the Spine: A Retrospective Multi-Center Analysis

Background/Objectives: Surgical site infections (SSIs) in spine surgery pose significant risks, including neurological deficits, prolonged hospital stays, and increased healthcare costs. SSIs are classified by their location and include superficial, deep, and organ/space (OS) infections. In spine surgery, OS SSIs include osteomyelitis, discitis, and spinal epidural abscess. These infections are difficult to treat with conservative measures, impart significant morbidity, and incur increasing hospital costs. Despite advancements in surgical technique and infection control, the literature is conflicting on which factors are associated with a significant increase in risk of SSIs after spinal surgery. There is also a significant gap in the literature in defining the risk factors specific to OS SSIs. This study aims to identify risk factors associated with SSI after spine surgery at a single institution, as well as provide descriptive characteristics of patients with OS SSIs. Methods: This retrospective study analyzed spinal surgeries performed at a multi-center, single-institution between 1 January 2019 and 9 February 2025. Neurosurgical patients who underwent spine surgery were identified by ICD-10 procedure and diagnosis codes. Surgical infections were classified based on the National Healthcare Safety Network (NHSN) criteria. Univariate and multivariate analyses were performed to assess associations between patient demographics, comorbidities, and infection risk. Results: Of the 2363 unique spinal surgery patients, 39 developed infections, with 14 meeting the NHSN criteria for OS SSI. The overall rate of SSIs at this institution was 1.65%. Significant risk factors for developing an SSI included cardiovascular disease (p = 0.017) and COPD (p = 0.012). Multivariate analysis confirmed both risk factors identified in the univariate analysis as independent risk factors, with adjusted odds ratios of 1.97 (p = 0.033) and 2.072 (p = 0.041), respectively. The commonly cultured pathogens included Staphylococcus aureus, Staphylococcus epidermidis, and methicillin-resistant Staphylococcus aureus. Conclusions: Male sex, diabetes mellitus, gastroesophageal reflux disease, hyperlipidemia, hypertension, hardware placement, and a history of smoking were more common in patients with SSI. In the OS SSI subgroup, cardiovascular disease and COPD were associated with an increased risk of developing an OS SSI. Future research is needed to investigate more detailed risk factors and include mitigating factors of OS infection into the analysis.

Vancomycin Antibiotic Prophylaxis Compared to Cefazolin Increases Risk of Surgical Site Infection Following Spine Surgery

Study DesignRetrospective analysis of randomized controlled trial.ObjectivesSurgical site infection (SSI) after spine surgery has severe negative health and financial consequences. Surgical antibiotic prophylaxis (SAP) is a routinely used method to prevent SSIs in the spine patient population. The most commonly used antibiotic is cefazolin, with vancomycin often being substituted in the case of penicillin or cephalosporin allergy. Vancomycin as SAP has been associated with increased SSI in the joint replacement literature, but this is not yet well defined in the spinal surgery population. The purpose of this study was to determine whether vancomycin SAP compared to cefazolin SAP is associated with increased risk of SSI.Methods535 patients, aged 16 years or older, underwent elective multi-level open posterior spinal fusion surgery at the thoracic, thoracolumbar, or lumbar levels. Demographic and operative characteristics as well as post-operative outcomes were compared between the following groups: (1) noninfected-cefazolin, (2) noninfected-vancomycin, (3) infected-cefazolin, and (4) infected-vancomycin. Primary outcomes were superficial and complicated (deep and organ/space) infections.ResultsThe following risk factors for SSI were identified in a logistic regression analysis: vancomycin (OR 2.498, 95% CI, 1.085-5.73, P = 0.031), increasing operating time (OR 1.006, 95% CI, 1.001-1.010 P = 0.010), weight (OR 1.020, 95% CI 1.006-1.034, P = 0.005), revision procedure (OR 2.343, 95% CI 1.283-4.277, P = 0.006), and depression (OR 2.366, 95% CI 1.284-4.360, P = 0.006).ConclusionsIn open posterior approach spinal fusion surgery, vancomycin SAP is associated with increased risk of infection compared to cefazolin SAP.

Institution-Based Quality and Safety Improvement Initiatives in Spine Surgery: A Scoping Review

BACKGROUND

Improving patient safety and healthcare quality is necessary to advance value-based health care. Spine surgery is complex, entailing joint efforts between different disciplines. This scoping review aimed to map the research on establishing and implementing institution-based quality improvement (QI) initiatives in spine surgery.

METHODS

Studies were identified in electronic searches of PubMed, Web of Science, and Scopus databases. Qualitative or quantitative studies that report the implementation of QI programs that occurred in or covered spine surgery were included; studies that did not describe the establishment, implementations, impacts, barriers, and facilitators of QI initiatives were excluded. Three reviewers independently screened the retrieved studies, and 2 reviewers extracted data and conducted a quality assessment of full-text articles. Studies were categorized according to dimensions of quality (timely, effective, patient-centered, efficient, equitable, and safe), and quality appraisal was conducted using the Standards for Quality Improvement Reporting Excellence reporting guidelines.

RESULTS

The search from the 3 databases yielded 2,876 returns; after removing duplicates, there were 1,274 in total. After screening, 228 records were entered into a full-text review, resulting in 133 records included in the review. Specifically, 88 addressed aspects of efficiency, 74 on safety, 32 on improving effectiveness, 23 on patient-centeredness, 7 on timeliness, and 1 on equity. Of the studies included, 71 rely on retrospective audits, 19 are prospective, and only 8 are interventional trials. Only 67 QI initiatives leveraged the advantages of multidisciplinary teams or the rigor of evidence-based protocols. Study gaps include limited follow-up, small sample sizes, and lack of comprehensive assessment using both objective measures and patient-reported outcomes.

CONCLUSIONS

This scoping review maps the current research on developing and implementing institution-based QI initiatives in spine surgery. Although most of the initiatives reported show improvement in the quality of health care and patient safety from multiple aspects, the sustainability of these initiatives remains unknown, and further studies are needed to trace the long-term effects and generalizability of these initiatives.

Comparison of mid-term outcomes between unilateral biportal endoscopic and minimally invasive transforaminal lumbar interbody fusion in the treatment of single-level lumbar degenerative disease

OBJECTIVE

To compare the mid-term clinical and radiological outcomes between unilateral biportal endoscopic transforaminal lumbar interbody fusion (ULIF) and minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) in the treatment of single-segment lumbar degenerative disease.

METHODS

Patients with L4-S1 disease treated with fusion surgery in our department between August 1, 2019 and June 30, 2020 were retrospectively analyzed. The patients were categorized into ULIF and MIS-TLIF groups based on the surgical method performed. The preoperative demographic baseline and operation-related indicators of the groups were compared, including operative time, estimated blood loss (EBL), postoperative drainage volume, time to ambulation, and postoperative hospital stay. The Visual Analog Scale (VAS) was utilized to assess the severity of back pain (VAS-B) and leg pain (VAS-L). The Oswestry Disability Index (ODI) and Japanese Orthopedic Association (JOA) scores were employed to evaluate the level of functionality. Bridwell criteria were used to evaluate interbody fusion. The lumbar lordotic angle (LLA), intervertebral disc height (IDH), and segmental lordotic angle (SLA) pre- and post-operatively were compared. The creatine kinase (CK), C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), and interleukin-6 (IL-6) levels pre- and post-operatively, and the complication rates were compared.

RESULTS

The baseline preoperative demographics of the ULIF (n=35) and MIS-TLIF (n=42) groups did not differ significantly. Compared with MIS-TLIF, ULIF had lower intraoperative blood loss and postoperative drainage volume and shorter time to ambulation and postoperative hospital stay, but longer operative time. The VAS-B, VAS-L, JOA, and ODI scores of both groups significantly improved. The VAS-L at 1 week postoperatively, the VAS-B at 1 week and 1 month postoperatively, and the JOA and ODI scores at 1 month postoperatively were better in the ULIF group. At 1 and 3 days postoperatively, the ULIF group exhibited substantially reduced levels of CRP, CK, and IL-6. The fusion rates did not differ significantly at 1 year, 2 years, and 3 years of follow-up. The IDH, SLA, and LLA improved significantly in both groups but no significant differences were observed between the two groups. Complication rates were comparable between the two groups.

CONCLUSIONS

Both ULIF and MIS-TLIF are proven to be safe and effective minimally invasive lumbar fusion techniques. Both achieve comparable outcomes in terms of interbody fusion rate, long-term pain relief, functional improvement, and complication rate. Compared with MIS-TLIF, ULIF has less intraoperative blood loss, less postoperative drainage volume, reduced inflammatory reaction, and faster postoperative pain relief and functional improvement.

The Effectiveness of Artificial Intelligence-based Pedicle Screw Trajectory Planning in Patients With Different Levels of Bone Mineral Density

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

To evaluate the effectiveness of pedicle screw trajectory planning based on artificial intelligence (AI) software in patients with different levels of bone mineral density (BMD).

SUMMARY OF BACKGROUND DATA

AI-based pedicle screw trajectory planning has potential to improve pullout force (POF) of screws. However, there is currently no literature investigating the efficacy of AI-based pedicle screw trajectory planning in patients with different levels of BMD.

METHODS

The patients were divided into 5 groups (group A-E) according to their BMD. The AI software utilizes lumbar spine CT data to perform screw trajectory planning and simulate AO screw trajectories for bilateral L3-5 vertebral bodies. Both screw trajectories were subdivided into unicortical and bicortical modes. The AI software automatically calculating the POF and pullout risk of every screw trajectory. The POF and risk of screw pullout for AI-planned screw trajectories and AO standard trajectories were compared and analyzed.

RESULTS

Forty-three patients were included. For the screw sizes, AI-planned screws were greater in diameter and length than those of AO screws ( P <0.05). In groups B-E, the AI unicortical trajectories had a POF of over 200N higher than that of AO unicortical trajectories. POF was higher in all groups for the AI bicortical screw trajectories compared with the AO bicortical screw trajectories ( P <0.05). AI unicortical trajectories in groups B-E had a lower risk of screw pullout compared with that of AO unicortical trajectories ( P <0.05).

CONCLUSIONS

AI unicortical screw trajectory planning for lumbar surgery in patients with BMD of 40-120 mg/cm 3 can significantly improve screw POF and reduce the risk of screw pullout.

Patients' experience on waiting for spinal arthrodesis: a qualitative study

PURPOSE

A number of studies have explored patients' subjective experience of waiting for spinal surgery, however, they did so through an investigation conducted post-operatively. Thus, the aim of this study was to explore the experience of patients while still on the waitlist for lumbar spinal arthrodesis.

METHODS

This qualitative study of semi-structured interviews was conducted at an orthopedic research institute in Italy. The interview track was developed by a team of professionals (physiotherapists, orthopedic surgeon, psychologist) and consisted of 40 questions. Fifteen patients, 10 females and 5 males aged between 23 and 80 years, waiting for spinal arthrodesis were interviewed. The interviews were performed, transcribed and analyzed by the multiprofessional team through thematic analysis using a reflexive approach.

RESULTS

Five main themes were generated: (1) Impact of persistent pain on patients' physical and psychological functioning; (2) Fear of the unknown and uncertainties; (3) Hope and regaining normality; (4) The impact of the unpredictability of the waiting time; (5) Need for better communication and information on the care pathway. Two minor themes were also produced.

CONCLUSIONS

These findings highlighted that patients on the waiting list for spinal arthrodesis need more certainty about waiting times, better communication with hospital staff, more thorough information about their care pathway. This could help patients feel more confident and may lead to more adequate expectations before surgery.

TRIAL REGISTRATION

The study protocol was registered on ClinicalTrials.gov database on 14/03/2022 with ID number NCT06323694.

Prevalence of Spin in Reviews on Intrawound Application of Vancomycin for Surgical Site Prophylaxis in Spine Surgery

STUDY DESIGN

Systematic Review.

OBJECTIVES

Systematic reviews and meta-analyses that aggregate data on the intrawound application of vancomycin for surgical site infection (SSI) prophylaxis in spine surgeries are at an increased risk of spin, the overstating of beneficial effects of an intervention. The purpose of this study was to identify studies that coalesce outcomes of intrawound vancomycin SSI prophylaxis in spine surgeries and define the prevalence and types of spin in the identified literature. Secondarily, this study aimed to identify patterns within study characteristics that were associated with certain spin types.

METHODS

This study was conducted using the Preferred Reporting Items for Systemic Reviews and Meta-Analyses guidelines. A search was performed in 4 databases (PubMed, SCOPUS, Medline and Cochrane) for systematic reviews and meta-analyses on intrawound vancomycin use for SSI prophylaxis in spine surgeries. Two authors independently assessed studies for inclusion criteria and then aggregated study characteristics: titles, publication journal and year, authors, level of evidence, etc. Each study was subsequently evaluated for the presence of 15 different spin types. Statistical analysis was performed for patterns between spin prevalence and study characteristics.

RESULTS

From the database search, 18 studies met the inclusion criteria. In total, 13 studies (72%) were found to have spin. The most common types of spin identified were spin type 9 ("Conclusion claims the beneficial effect of the experimental treatment despite reporting bias"), found in 9 (50.00%) studies and type 3 ("Selective reporting of or overemphasis on efficacy outcomes or analysis favoring the beneficial effect of the experimental intervention"), found in 7 (38.89%) studies.

CONCLUSIONS

There is a high prevalence of spin in systematic reviews and meta-analyses on the intrawound application of vancomycin for SSI prophylaxis in spine surgery. Our analysis demonstrated that studies tended to selectively report positive findings while minimizing negative outcomes within abstracts.

Disparities Attributable to Sex Differences in 4680 Lumbar Fusion Outcomes

BACKGROUND

While studies have examined the relationship between sex and outcomes after lumbar fusion surgery, few have strictly controlled for other patient-level variables. In this study, we use coarsened exact matching (CEM) to determine the effect of patient-reported sex on spinal fusion outcomes.

METHODS

Outcomes across 4680 consecutive adult single-level, posterior-only lumbar fusions at a multihospital academic medical center were retrospectively assessed. First, univariate analyses were performed to broadly examine the effect of sex on surgical outcomes, uncontrolled for other patient factors. Next, the population was split by sex (male vs. female) and matched 1:1 on demographic and medical factors known to influence outcomes (including age, race, smoking status, and past surgical history) using CEM. CEM effectively controls for confounding variable bias by creating pairs of matched samples and preserving the fidelity of each covariate through binning. Primary outcomes included 30-day and 90-day readmissions, emergency department visits, reoperations, and mortality. Secondary outcomes included discharge disposition and length of hospital stay.

RESULTS

Between otherwise exactly matched male-female pairs, females were less likely to be discharged home (odds ratio 1.70, P < 0.001) and had a longer length of stay (mean: 95.7 vs. 87 hours, P < 0.001). No differences in readmissions or reoperations were observed between matched cohorts.

CONCLUSIONS

Female patients encountered longer hospital stays and higher odds of nonhome discharge after single-level lumbar fusion compared to otherwise exactly matched male patients.

Patient acceptance of reoperation risk for lumbar decompression versus fusion

BACKGROUND CONTEXT

Lumbar decompression and lumbar fusion are effective methods of treating spinal compressive pathologies refractory to conservative management. These surgeries are typically used to treat different spinal problems, but there is a growing body of literature investigating the outcomes of either approach for patients with lumbar degenerative spondylolisthesis and stenosis. Different operations are associated with different risks and different potential needs for reoperation. Patient acceptance of reoperation rates after spinal surgery is currently not well understood.

PURPOSE

The purpose of this study is to identify patient tolerance for reoperation rates following lumbar decompression and lumbar fusion surgery.

DESIGN

A qualitative and quantitative survey intended to capture information on patient preferences was administered.

PATIENT SAMPLE

Written informed consent was obtained from patients presenting to 2 spinal clinics.

OUTCOME MEASURES

Patients were asked their threshold tolerance for reoperation rates in the context of choosing a smaller (decompression) versus larger (fusion) spinal surgery.

METHODS

A survey was administered to patients at 2 spinal clinics-1 surgical and 1 nonsurgical. A consecutive series of new patients over multiple clinic days who agreed to participate in the study and filled out the survey are reported on here. Patients were asked to assess, contemplating a problem that could either be treated with lumbar decompression or lumbar fusion, the level at which 1) the likelihood that needing a repeat surgery within 3 to 5 years would change their mind about choosing the decompression operation and cause them to choose the fusion operation and then 2) the likelihood of needing a repeat surgery within 3 to 5 years that would be acceptable to them after the fusion operation. The distribution of patient responses was assessed with histograms and descriptive statistics.

RESULTS

Ninety patients were surveyed, and of these, 73 patients (81.1%) returned fully completed questionnaires. The median reoperation acceptance rates after a decompression was <60%, while the median acceptable revision rate when contemplating the fusion surgery was 10%.

CONCLUSIONS

Patient acceptance for the potential need for revision surgery is higher when considering a decompression compared to a fusion operation. Reoperation risk rates along with the magnitude of the surgical intervention are important considerations in determining patients' surgical preferences. Understanding patient preferences and risk tolerances can aid clinicians in shared decision-making, potentially improving patient satisfaction and outcomes in the several lumbar pathologies which can be ameliorated with either decompression or fusion.

Comparison of reoperation incidence after fusion versus decompression for lumbar degenerative disease: A propensity score-weighted study

BACKGROUND

Reoperation after lumbar spine surgery is a major issue for both patients and physicians. It is uncertain whether fusion is superior to decompression alone for lumbar degenerative disease regarding reoperation rate. We aim to evaluate the reoperation rate after fusion surgery for lumbar degenerative disease compared with decompression alone.

METHODS

This study was conducted under a retrospective cohort design in patients undergoing fusion or decompression alone in one or two levels for lumbar degenerative disease using a Japanese claims-based database. Primary outcome was reoperation incidence during the follow-up period, and secondary outcome was reoperation incidence within 90 days postoperatively. Confounding factors were handled using propensity score overlap weighting. Cumulative incidence of reoperation was calculated from the Kaplan-Meier curve and hazard ratios (HRs) and 95% confidence intervals (CIs) for reoperation were estimated using Cox proportional hazards regression models.

RESULTS

8497 patients (2051 patients in the fusion group and 6446 in the decompression alone group) were included in the study. There was no difference in reoperation rate between fusion and decompression alone (weighted HR 0.85 [95% CI 0.69 to 1.04]; p = 0.11).

CONCLUSIONS

Among patients with lumbar degenerative disease who underwent fusion or decompression alone, no significant difference was observed between the two groups.

Early prediction of functional impairment at hospital discharge in patients with osteoporotic vertebral fracture: a machine learning approach

Although conservative treatment is commonly used for osteoporotic vertebral fracture (OVF), some patients experience functional disability following OVF. This study aimed to develop prediction models for new-onset functional impairment following admission for OVF using machine learning approaches and compare their performance. Our study consisted of patients aged 65 years or older admitted for OVF using a large hospital-based database between April 2014 and December 2021. As the primary outcome, we defined new-onset functional impairment as a Barthel Index ≤ 60 at discharge. In the training dataset, we developed three machine learning models (random forest [RF], gradient-boosting decision tree [GBDT], and deep neural network [DNN]) and one conventional model (logistic regression [LR]). In the test dataset, we compared the predictive performance of these models. A total of 31,306 patients were identified as the study cohort. In the test dataset, all models showed good discriminatory ability, with an area under the curve (AUC) greater than 0.7. GBDT (AUC = 0.761) outperformed LR (0.756), followed by DNN (0.755), and RF (0.753). We successfully developed prediction models for new-onset functional impairment following admission for OVF. Our findings will contribute to effective treatment planning in this era of increasing prevalence of OVF.

A curved compliant spinal bone anchor to enhance fixation strength

Pedicle screws have long been established as the gold standard for spinal bone fixation. However, their fixation strength can be compromised in cases of low bone density, particularly in osteoporotic bone, due to the reliance on a micro-shape lock between the screw thread and the surrounding bone. To address this challenge, we propose augmenting conventional pedicles screws with a curved compliant anchor. This anchor integrates a curved super-elastic nitinol rod that is advanced through a canulated pedicle screw, forming a macro-shape lock within the vertebral body to aid the fixation strength. Both placement safety and fixation strength of this novel spinal bone anchor were validated on tissue phantoms (Sawbones). The radius of the curved compliant anchor's path demonstrates high precision while exhibiting strong dependence on the bone density in which the anchor is placed. When the curved compliant anchor is combined with a conventional pedicle screw, the mean maximum pull-out force elevated to 290 N, marking a 14% enhancement in pull-out resistance compared to using pedicle screw alone. Further augmentation with multiple curved compliant anchors holds promise for even greater fixation. The application of a curved compliant spinal bone anchor offers a promising means of increasing the fixation strength of pedicles screws, which is especially relevant in challenging clinical scenarios such a patient suffering from osteoporosis.

Diabetes and heart disease do not affect short-term lumbar fusion outcomes accounting for other risk factors in a matched cohort analysis

Objectives

Comprehensive preoperative management involves the identification and optimization of medical comorbidities while avoiding excessive healthcare utilization. While diabetes and heart disease are major causes of morbidity that can worsen surgical outcomes, further study is needed to evaluate how well current perioperative strategies mitigate their risks. This study employs an exact matching protocol to isolate the effects of both diabetes and cardiovascular disease on spine surgery outcomes.

Methods

4680 consecutive patients undergoing single-level, posterior-only lumbar fusion were retrospectively enrolled. Univariate logistic regression was performed on comorbidity subgroups, then coarsened exact matching (CEM) was employed for patients with diabetes or cardiovascular disease. Patients were matched 1:1 on ten patient and procedural characteristics known to affect neurosurgical outcomes. Separate pairs of exact-matched cohorts were generated to isolate both cardiovascular disease (matched n = 192), and diabetes (matched n = 380). Primary outcomes were surgical complications; length of stay; discharge disposition (home vs. non-home); and 30- and 90-day Emergency Department (ED) visits, readmissions, reoperations, and mortality.

Results

Cardiovascular disease and diabetes subgroups were not associated with short term outcomes after matching to control for confounders. Compared to univariate statistics, this method demonstrates that confounding control variables may drive outcomes more than these comorbidities themselves.

Conclusion

Between otherwise exactly matched patients undergoing lumbar fusion, diabetes and cardiovascular disease posed no greater risk of short-term adverse outcomes. This suggests proper selection criteria for surgical candidates and effective current perioperative strategies to mitigate these common comorbidities. Further studies are warranted to assess and optimize the cost-effectiveness of preoperative management for patients with common comorbidities.

Comparison of midline lumbar interbody fusion and minimally invasive transforaminal lumbar interbody fusion for treatment of lumbar degeneration disease

Midline lumbar interbody fusion (MIDLIF) and minimally invasive transforaminal interbody fusion (MIS-TLIF) are two minimally invasive lumbar fusion methods that have gained popularity in the past two decades. MIDLIF involves the use of cortical bone trajectory screws, whereas MIS-TLIF uses traditional pedicle screws. However, there is a significant lack of research directly examining the clinical efficacy of these two methods in treating single-segment lumbar degenerative diseases. Hence, the objective of our retrospective study is to assess and contrast the surgical and clinical results of MIDLIF and MIS-TLIF. The study population comprised 133 patients diagnosed with single-segment lumbar degenerative disease that received treatment using either MIDLIF (n = 65) or MIS-TLIF (n = 68) in our department from January 2017 to January 2019. The fusion rates for MIDLIF were consistently lower than MID-TLIF at all post-operative time periods of follow-up, however, the differences between the two groups were not statistically significant. The 1-year fusion rates were 81.5% (MIDLIF) and 83.8% (MIS-TLIF) (P = 0.728), and the 2-year fusion rates were 87.7% (MIDLIF) and 91.2% (MIS-TLIF) (P = 0.513). The final follow-up fusion rates were 93.8% (MIDLIF) and 95.6% (MIS-TLIF) (P = 0.653). MIDLIF had several advantages over MIS-TLIF, including a shorter operative time (135.2 ± 15.70 vs. 160.1 ± 17.2 min, P < 0.001), decreased intraoperative blood loss (147.9 ± 36.4 vs. 169.5 ± 24.7 mL, P < 0.001), and a shorter length of hospital stay (10.8 ± 3.1 vs. 12.4 ± 4.1d; P = 0.014). No significant differences were seen between the groups in terms of the postoperative day of ambulation, Oswestry dysfunction index (ODI) scores, and visual analog scale (VAS) scores for leg and lower back pain (P > 0.05). Although not significant (P = 0.707), MIDLIF (13.8%) had fewer overall complications than MIS-TLIF (16.2%). Therefore, compared to MIS-TLIF, MIDLIF provides perioperative benefits while achieving the same outcomes as MIS-TLIF in terms of fusion rate, pain relief, functional improvement, and complication rate.

Trends, costs, and complications associated with after-hours surgery and unscheduled hospitalization in spinal surgery

Aims

The escalating demand for medical resources to address spinal diseases as society ages is an issue that requires careful evaluation. However, few studies have examined trends in spinal surgery, especially unscheduled hospitalizations or surgeries performed after hours, through large databases. Our study aimed to determine national trends in the number of spine surgeries in Japan. We also aimed to identify trends in after-hours surgeries and unscheduled hospitalizations and their impact on complications and costs.

Methods

We retrospectively investigated data extracted from the Diagnosis Procedure Combination database, a representative inpatient database in Japan. The data from April 2010 to March 2020 were used for this study. We included all patients who had undergone any combination of laminectomy, laminoplasty, discectomy, and/or spinal arthrodesis.

Results

This investigation included 739,474 spinal surgeries and 739,215 hospitalizations in Japan. There was an average annual increase of 4.6% in the number of spinal surgeries. Scheduled hospitalizations increased by 3.7% per year while unscheduled hospitalizations increased by 11.8% per year. In-hours surgeries increased by 4.5% per year while after-hours surgeries increased by 9.9% per year. Complication rates and costs increased for both after-hours surgery and unscheduled hospitalizations, in comparison to their respective counterparts of in-hours surgery and scheduled hospitalizations.

Conclusion

This study provides important insights for those interested in improving spine care in an ageing society. The swift surge in after-hours spinal surgeries and unscheduled hospitalizations highlights that the medical needs of an increasing number of patients due to an ageing society are outpacing the capacity of existing medical resources.

Unchanged incidence of major adverse events amidst rising surgical interventions for osteoporotic vertebral fractures, 2015-2021

This study investigated treatment trends and major adverse events in patients hospitalized for osteoporotic vertebral fracture (OVF). The frequency of surgical interventions for OVF increased significantly, but this did not decrease major adverse events. The findings underscore the necessity for reevaluating OVF management strategies.

PURPOSE

Osteoporotic vertebral fracture (OVF) is a common condition in the aging population, often leading to increased morbidity and mortality. Here, we analyzed treatment trends and incidence of major adverse events in patients hospitalized for OVF.

METHODS

We conducted a cross-sectional descriptive study, using a large Japanese hospital administrative database. The cohort included hospitalized patients aged 65 years or older, admitted for OVF from January 2015 to December 2021. The primary outcomes were the trend in the proportion of the patients undergoing surgery for OVF and the incidence of major adverse events within 30 days of admission. As a secondary outcome, we evaluated the trend in hospitalization costs.

RESULTS

The study cohort consisted of 14,714 patients, with a mean age of 82.4 years. There was a significant increase in surgical interventions for OVF, from 3.7% of patients in 2015 to 9.8% in 2021 (p < 0.001). The incidence of major adverse events remained unchanged, with a risk ratio of 1.09 (95% confidence interval, 0.88 to 1.35) in 2021 compared to 2015. Average hospitalization costs increased significantly, from $7,570.6 (SD 6,047.0) in 2015 to $9,502.9 (SD 7,231.5) in 2021 (p < 0.001).

CONCLUSION

Despite a significant increase in the proportion of surgical intervention for OVF, no reduction in the risk of major adverse events was observed between 2015 and 2021. Surgeons and policy makers need to interpret these findings and work towards an optimized approach to the management of OVF in the aging population.

Evolution of Titanium Interbody Cages and Current Uses of 3D Printed Titanium in Spine Fusion Surgery

PURPOSE OF REVIEW

To summarize the history of titanium implants in spine fusion surgery and its evolution over time.

RECENT FINDINGS

Titanium interbody cages used in spine fusion surgery have evolved from solid metal blocks to porous structures with varying shapes and sizes in order to provide stability while minimizing adverse side effects. Advancements in technology, especially 3D printing, have allowed for the creation of highly customizable spinal implants to fit patient specific needs. Recent evidence suggests that customizing shape and density of the implants may improve patient outcomes compared to current industry standards. Future work is warranted to determine the practical feasibility and long-term clinical outcomes of patients using 3D printed spine fusion implants. Outcomes in spine fusion surgery have improved greatly due to technological advancements. 3D printed spinal implants, in particular, may improve outcomes in patients undergoing spine fusion surgery when compared to current industry standards. Long term follow up and direct comparison between implant characteristics is required for the adoption of 3D printed implants as the standard of care.

Frailty is not an independent risk factor for worse clinical outcomes in lumbar spinal surgery: a prospective cohort study

PURPOSE

Recently, many studies revealed that frailty affects unfavorably on postoperative outcomes in lumbar spinal diseases. This study aimed to investigate the relationship between frailty and clinical outcomes while identifying risk factors associated with worse clinical outcomes following lumbar spinal surgery.

METHODS

From March 2019 to February 2021, we prospectively enrolled eligible patients with degenerative lumbar spinal diseases requiring surgery. Frailty was assessed preoperatively. To identify the impact of frailty on lumbar spinal diseases, clinical outcomes, which were measured with patient-reported outcomes (PROs) and postoperative complications, were compared according to the frailty. PROs were assessed preoperatively and one year postoperatively. In addition, risk factors for preoperative and postoperative worse clinical outcomes were investigated.

RESULTS

PROs were constantly lower in the frail group than in the non-frail group before and after surgery, and the change of PROs between before and after surgery and postoperative complications were not different between the groups. In addition, frailty was a persistent risk factor for postoperative worse clinical outcome before and after surgery in lumbar spinal surgery.

CONCLUSION

Frailty persistently affects the clinical outcome negatively before and after surgery in lumbar spinal surgery. However, as the change of the clinical outcome is not different between the frail group and the non-frail group, it is difficult to interpret whether the frail patients are vulnerable to the surgery. In conclusion, frailty is not an independent risk factor for worse clinical outcome in lumbar spinal surgery.

Preoperative nutritional status and postoperative health outcomes in older adults undergoing spine surgery: Electronic health records analysis

AIM

To examine whether a high nutritional risk status, assessed via the Geriatric Nutritional Risk Index (GNRI), is independently associated with postoperative health outcomes, including unplanned intensive care unit (ICU) admissions, infectious complications, and prolonged length of stay in older patients undergoing spine surgery.

METHODS

We conducted a retrospective descriptive study analyzing electronic health records from a tertiary hospital, including data from 1,014 patients aged ≥70 undergoing elective spine surgery between February 2013 and March 2023.

RESULTS

High nutritional risk patients had significantly higher odds of unplanned ICU admission, infectious complications, and prolonged length of stay compared to low-risk patients. For each one-point increase in GNRI, there was a significant 0.91- and 0.95-fold decrease in the odds of unplanned ICU admission and infectious complications, respectively.

CONCLUSION

GNRI screening in older patients before spine surgery may have potential to identify those at elevated risk for postoperative adverse outcomes.

Analgesic efficacy of classical thoracolumbar interfascial plane block versus modified thoracolumbar interfascial plane block in patients undergoing lumbar disc surgeries: A comparative, randomised controlled trial

Background and Aims

We compared classical (medial) and modified (lateral) thoracolumbar interfascial plane block (TLIP) with only general anaesthesia (GA) using multimodal analgesia in patients undergoing lumbar disc surgeries.

Methods

In this study, 100 patients aged 18-70 years were randomised to Group cTLIP (conventional TLIP block with 20 mL of 0.25% ropivacaine with GA), Group mTLIP (modified TLIP block with 20 mL of 0.25% ropivacaine with GA), and Group C (only GA using multimodal analgesia). The primary outcome was to assess the total peri-operative opioid consumption in the first 24 h. The secondary outcomes were to assess pain score upon arriving in the post-anaesthesia care unit, time to first analgesic need after surgery, post-operative opioid consumption in 24 h, and incidence of nausea and vomiting.

Results

The total peri-operative opioid consumption in Group cTLIP (507.58 (258.55) μg) and Group mTLIP (491.67 (165.39) μg) was significantly lower than that in Group C (1225.4 (237.03) μg); (P < 0.001). However, it was comparable between groups cTLIP and mTLIP (P = 0.767). Pain score was comparable in groups cTLIP and mTLIP. It was significantly lower than Group C (P = 0.001). Rescue analgesia was needed in all (100%) patients of Group C but in only 15.2% of patients of the cTLIP and mTLIP groups. No patient in groups cTLIP and mTLIP complained of nausea and vomiting in the first 24 h, whereas it was significantly higher (61.8%) in Group C (P = 0.001).

Conclusion

The analgesic effect of the modified TLIP block was not superior to the conventional TLIP block. Both techniques provided the same intra-operative and post-operative analgesia for lumbar disc surgeries.

Clinical and Economic Outcomes of Patients with Osteoporosis Undergoing Spine Fusion Surgery in Japan

Introduction

Spinal fusion surgery with instrumentation is a treatment of choice for many spinal disorders; however, there is little data related to factors associated with early and late outcomes, especially among patients with poor bone quality (e.g., osteoporosis). We conducted this study to characterize the epidemiology and outcomes of patients undergoing spinal fusion surgery with instrumentation in Japan, especially in patients with poor bone quality and those needing additional fixation methods.

Methods

This retrospective observational study used real-world health insurance claims data from the Japanese Medical Data Vision. Adult patients undergoing an index spinal fusion procedure from April 1, 2010, to September 30, 2017, with procedural details, length of stay (LOS), total in-hospital costs, spine-related reoperation, all-cause readmission, and postoperative complications recorded. Data were summarized descriptively overall, by osteoporosis status, and additional fixation method used, and were analyzed in bivariate analyses. Multivariate logistic and linear regressions were used to explore associations between covariates and variables of interest.

Results

A total of 22,932 patients (mean age, 67.3 years; 51.2% male) met the study criteria and were included. A total of 5,288 (23.0%) patients had osteoporosis, and 2,507 (10.9%) needed additional fixation methods; these patients were older, more frequently female, and had higher Elixhauser comorbidity index scores. Osteoporosis and additional fixation use were also associated with longer LOS, higher hospital costs, and higher rates of complications.

Conclusions

Patients with osteoporosis and those needing additional fixation methods have a higher risk for procedural and postoperative complications, reoperation, longer LOS, and higher total hospital costs.

Addressing the Challenge of Spine Patient Triage: Development of a Simple Algorithm for Identification of Potential Surgical Candidates

INTRODUCTION

Given that most spine conditions do not require surgical intervention, using surgeons to manage the subset of patients potentially requiring surgery is the most efficient resource allocation strategy. The purpose of this study was to develop a simple algorithm for identifying patients most likely to require spine surgery that could be used to appropriately triage this population to surgeons.

METHODS

A retrospective review of 5,886 consecutive new patients presenting to a multidisciplinary spine clinic from March 2021 to September 2022 was conducted. The primary outcome was whether a patient underwent spine surgery during the study period. A total of 64 independent variables were recorded from patient intake and the first visit. A gradient boosted model was generated to identify the independent variables most associated with undergoing surgery. The five most important variables were entered into a multiple logistic regression model, and a simplified decision support tool was generated and assessed.

RESULTS

Overall, 440 of 5886 patients (7.5%) underwent surgery during the study period. The following variables were identified as the top five predictors of spine surgery: patient goal of interest in learning about spine surgery, history of spine injections, difficulty walking a mile, radicular symptoms greater than axial symptoms, and increased age. Each of these variables was confirmed to be independently associated with undergoing surgery (all P < 0.001). The decision support tool yielded a sensitivity of 60.0%, specificity of 76.6%, likelihood ratio of 2.56, positive predictive value of 17.2%, and negative predictive value of 96.0% for predicting surgery. An AUC of 0.683 was achieved.

CONCLUSION

A simple 5-question algorithm incorporating patient demographics, symptoms, treatment history, physical function, and patient goals may improve the ability of practices to identify potential spine surgery candidates before their first visit. Prospective application and evaluation of the algorithm to evaluate whether it improves the triage of appropriate patients to spine surgeons is warranted.

Risk Factors for Postoperative Ileus Following Spine Surgery: A Systematic Review With Meta-Analysis

STUDY DESIGN

Systematic review and meta-analysis.

OBJECTIVES

Postoperative ileus (POI) can negatively impact patient recovery and surgical outcomes after spine surgery. Emerging studies have focused on the risk factors for POI after spine surgery. This study aimed to review the available literature on risk factors associated with POI following elective spine surgery.

METHODS

Electronic databases were searched to identify relevant studies. Meta-analysis was performed using random-effect model. Risk factors for POI were summarized using pooled odds ratio (OR) with 95% confidence intervals (CI).

RESULTS

Twelve studies were included in the present review. Meta-analysis demonstrated males exhibited a higher risk of POI than females odds ratio (OR, 1.76; 95% CI, 1.54-2.01). Patients with anemia had a higher risk of POI than those without anemia (OR, 1.48; 95% CI, 1.04-2.11). Patients with liver disease (OR, 3.3; 95% CI, 1.2-9.08) had a higher risk of POI. The presence of perioperative fluid and electrolyte imbalances was a predictor of POI (OR, 3.24; 95% CI, 2.62-4.02). Spine surgery involving more than 3 levels had a higher risk of POI compared to that with 1-2 levels (OR, 1.82; 95% CI, 1.03-3.23).

CONCLUSIONS

Male sex and the presence of anemia and liver disease were significant patient factors associated with POI. Perioperative fluid and electrolyte imbalance and multilevel spine surgery significantly increased the risk of POI. In addition, through this comprehensive review, we identified several perioperative risk factors associated with the development of POI after spine surgery.

Clinical Outcomes of Percutaneous Transforaminal Endoscopic Discectomy Assisted with Selective Nerve Root Block for Treating Radicular Pain with Diagnostic Uncertainty in the Elderly

PURPOSE

To investigate the clinical outcomes of percutaneous transforaminal endoscopic discectomy assisted with selective nerve root block for treating radicular pain with diagnostic uncertainty in the elderly.

METHODS

A total number of 36 elderly patients were included in the study. Clinical outcomes collected for analysis include operative time, hospital stay time, Visual Analog Scale, and Oswestry Disability Index before and after the surgery, the global outcome based on the Macnab outcome criteria.

RESULTS

Seventeen males and nineteen females with a mean age of 73.72 ± 7.15 were included in this study. Radicular pain was the main complaint of all the patients with the least symptom duration of two months. Radiological findings showed that 80.6% of the patients with multilevel disc herniation, 16.7% received lumbar fusion surgery before, and 8.3% with degenerative scoliosis. Besides, 69.4% of the patients have at least one comorbidity. 85.4% of the patients showed a positive response to selective nerve root block, and 91.6% of the patients reported a favorable outcome at the last follow-up. The mean value of pre-operative leg pain was 7.56 ± 0.74 and dramatically decreased after surgery (2.47 ± 0.81, P < 0.001). Besides, the mean value of Oswestry Disability Index decreased from 43.03 ± 4.43 to 5.92 ± 5.24 (P < 0.001) one year after the surgery.

CONCLUSION

Multilevel degeneration of the lumbar spine is common in elderly patients. Identifying the responsible segment and decompressing the nerve root through minimally invasive surgery can provide a satisfactory clinical outcome for those with radicular pain as their primary complaint. And selective nerve root block is a reliable diagnostic tool for those with an ambiguous diagnosis.

Postoperative analgesic options after spine surgery: finding the optimal treatment strategies

INTRODUCTION

Spine surgery is one of the most common types of surgeries performed in the United States; however, managing postoperative pain following spine surgery has proven to be challenging. Patients with spine pathologies have higher incidences of chronic pain and resultant opioid use and potential for tolerance. Implementing a multimodal plan for postoperative analgesia after spine surgery can lead to enhanced recovery and outcomes.

AREAS COVERED

This review presents several options for analgesia following spine surgery with an emphasis on multimodal techniques to best aid this specific patient population. In addition to traditional therapeutics, such as acetaminophen, non-steroidal anti-inflammatory medications, and opioids, we discuss intrathecal morphine administration and emerging regional anesthesia techniques.

EXPERT OPINION

Several adjuncts to improve analgesia following spine surgery are efficacious in the postoperative period. Intrathecal morphine provides sustained analgesia and can be instilled intraoperatively by the surgical team under direct visualization. Local anesthetics deposited under ultrasound guidance by an anesthesiologist trained in regional techniques also provide the opportunity for single injections or continuous analgesia via an indwelling catheter.

Dosing of lumbar spinal manipulative therapy and its association with escalated spine care: A cohort study of insurance claims

OBJECTIVE

The objective of this study was to evaluate the relationship between three distinct spinal manipulative therapy dose groups and escalated spine care by analyzing insurance claims from a cohort of patients with low back pain.

METHODS

We compared three distinct spinal manipulative therapy dose groups (low = 1 SMT visits, moderate = 2-12 SMT visits, high = 13+ SMT visits), to a control group (no spinal manipulative therapy) regarding the outcome of escalated spine care. Escalated spine care procedures include imaging studies, injection procedures, emergency department visits, surgery, and opioid medication use. Propensity score matching was performed to address treatment selection bias. Modified Poisson regression modeling was used to estimate the relative risk of spine care escalation among three spinal manipulative therapy doses, adjusting for age, sex, retrospective risk score and claim count.

RESULTS

83,025 claims were categorized into 11,114 unique low back pain episodes; 8,137 claims had 0 spinal manipulative therapy visits, with the remaining episodes classified as low dose (n = 404), moderate dose (n = 1,763) or high dose (n = 810). After propensity score matching, 5,348 episodes remained; 2,454 had 0 spinal manipulative therapy visits with the remaining episodes classified as low dose (n = 404), moderate dose (n = 1,761), or high dose (n = 729). The estimated relative risk (vs no spinal manipulative therapy) for any escalated spine care was 0.45 (95% confidence interval 0.38, 0.55, p <0.001), 0.58 (95% confidence interval 0.53, 0.63, p <0.001), and 1.03 (95% confidence interval 0.95, 1.13, p = 0.461) for low, moderate, and high dose spinal manipulative therapy groups, respectively.

CONCLUSIONS

For claims associated with initial episodes of low back pain, low and moderate dose spinal manipulative therapy groups were associated with a 55% and 42% reduction, respectively, in the relative risk of any escalated spine care.

Radiologic Assessment of Interbody Fusion: A Systematic Review on the Use, Reliability, and Accuracy of Current Fusion Criteria

BACKGROUND

Lumbar interbody fusion (IF) is a common procedure to fuse the anterior spine. However, a lack of consensus on image-based fusion assessment limits the validity and comparison of IF studies. This systematic review aims to (1) report on IF assessment strategies and definitions and (2) summarize available literature on the diagnostic reliability and accuracy of these assessments.

METHODS

Two searches were performed according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines. Search 1 identified studies on adult lumbar IF that provided a detailed description of image-based fusion assessment. Search 2 analyzed studies on the reliability of specific fusion criteria/classifications and the accuracy assessed with surgical exploration.

RESULTS

A total of 442 studies were included for search 1 and 8 studies for search 2. Fusion assessment throughout the literature was highly variable. Eighteen definitions and more than 250 unique fusion assessment methods were identified. The criteria that showed most consistent use were continuity of bony bridging, radiolucency around the cage, and angular motion <5°. However, reliability and accuracy studies were scarce.

CONCLUSION

This review highlights the challenges in reaching consensus on IF assessment. The variability in IF assessment is very high, which limits the translatability of studies. Accuracy studies are needed to guide innovations of assessment. Future IF assessment strategies should focus on the standardization of computed tomography-based continuity of bony bridging. Knowledge from preclinical and imaging studies can add valuable information to this ongoing discussion.

LEVEL OF EVIDENCE

Diagnostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Postoperative Use of the Muscle Relaxants Baclofen and/or Cyclobenzaprine Associated With an Increased Risk of Delirium Following Lumbar Fusion

STUDY DESIGN

Retrospective, single-center, cohort study.

OBJECTIVE

Investigate whether the incidence of postoperative delirium in older adults undergoing spinal fusion surgery is associated with postoperative muscle relaxant administration.

SUMMARY OF BACKGROUND DATA

Baclofen and cyclobenzaprine are muscle relaxants frequently used for pain management following spine surgery. Muscle relaxants are known to cause central nervous system side effects in the outpatient setting and are relatively contraindicated in individuals at high risk for delirium. However, there are no known studies investigating their side effects in the postoperative setting.

METHODS

Patients over 65 years of age who underwent elective posterior lumbar fusion for degenerative spine disease were stratified into two treatment groups based on whether postoperative muscle relaxants were administered on postoperative day one as part of a multimodal analgesia regimen. Doubly robust inverse probability weighting with cox regression for time-dependent covariates was used to examine the association between postoperative muscle relaxant use and the risk of delirium while controlling for variation in baseline characteristics.

RESULTS

The incidence of delirium was 17.6% in the 250 patients who received postoperative muscle relaxants compared with 7.9% in the 280 patients who did not receive muscle relaxants ( P=0.001 ). Multivariate analysis to control for variation in baseline characteristics between treatment groups found that patients who received muscle relaxants had a 2.00 (95% CI: 1.14-3.49) times higher risk of delirium compared with controls ( P=0.015 ).

CONCLUSION

Postoperative use of muscle relaxants as part of a multimodal analgesia regimen was associated with an increased risk of delirium in older adults after lumber fusion surgery. Although muscle relaxants may be beneficial in select patients, they should be used with caution in individuals at high risk for postoperative delirium.

Proximal Junctional Failure after Corrective Surgery: Focusing on Elderly Patients with Severe Sagittal Imbalance

Background

Previous reports with proximal junctional failure (PJF) included relatively young patients or deformity without sagittal imbalance. The present study focused on the two well-known risk factors for PJF, old age and severe sagittal imbalance. With these high-risk patients, the present study aimed to identify a strategy that could prevent PJF and to investigate whether the degree of correction would really affect the PJF occurrence.

Methods

Patients who were ≥ 60 years of age and underwent long fusion (≥ 4) to the sacrum for severe sagittal imbalance (defined as pelvic incidence minus lumbar lordosis [PI-LL] ≥ 30°) were included. PJF was defined as a vertebral fracture at the uppermost instrumented vertebra (UIV) or UIV+1, failure of UIV fixation, myelopathy, or any need for proximal extension of fusion. Presumed risk factors were compared between the patients with and without PJF.

Results

Total 146 patients (mean age, 68.4 years) with preoperative mean PI-LL of 46.8° were included. PJF developed in 39 patients (26.7%) at a mean of 18.1 months after surgery. Multivariate analysis showed that osteoporosis (odds ratio [OR], 2.812; p = 0.019) and UIV located below T10 (OR, 3.773; p = 0.010) were significant risk factors for developing PJF. However, the degree of correction did not affect PJF occurrence.

Conclusions

The present study indicates that osteoporosis should be well corrected preoperatively and extending the fusion above T10 should be considered for severe imbalance in old patients. However, the amount of correction was not associated with PJF development.

Impact of frailty on the outcomes of patients undergoing degenerative spine surgery: a systematic review and meta-analysis

BACKGROUND

Degenerative spinal diseases are common in older adults with concurrent frailty. Preoperative frailty is a strong predictor of adverse clinical outcomes after surgery. This study aimed to investigate the association between health-related outcomes and frailty in patients undergoing spine surgery for degenerative spine diseases.

METHODS

A systematic review and meta-analysis were performed by electronically searching Ovid-MEDLINE, Ovid-Embase, Cochrane Library, and CINAHL for eligible studies until July 16, 2022. We reviewed all studies, excluding spinal tumours, non-surgical procedures, and experimental studies that examined the association between preoperative frailty and related outcomes after spine surgery. A total of 1,075 articles were identified in the initial search and were reviewed by two reviewers, independently. Data were subjected to qualitative and quantitative syntheses by meta-analytic methods.

RESULTS

Thirty-eight articles on 474,651 patients who underwent degenerative spine surgeries were included and 17 papers were quantitatively synthesized. The health-related outcomes were divided into clinical outcomes and patient-reported outcomes; clinical outcomes were further divided into postoperative complications and supportive management procedures. Compared to the non-frail group, the frail group was significantly associated with a greater risk of high mortality, major complications, acute renal failure, myocardial infarction, non-home discharge, reintubation, and longer length of hospital stay. Regarding patient-reported outcomes, changes in scores between the preoperative and postoperative Oswestry Disability Index scores were not associated with preoperative frailty.

CONCLUSIONS

In degenerative spinal diseases, frailty is a strong predictor of adverse clinical outcomes after spine surgery. The relationship between preoperative frailty and patient-reported outcomes is still inconclusive. Further research is needed to consolidate the evidence from patient-reported outcomes.

Mobile health supported multi-domain recovery trajectories after major arthroplasty or spine surgery: a pilot feasibility and usability study

BACKGROUND

Recovery after surgery intersects physical, psychological, and social domains. In this study we aim to assess the feasibility and usability of a mobile health application called PositiveTrends to track recovery in these domains amongst participants undergoing hip, knee arthroplasty or spine surgery. Our secondary aim was to generate procedure-specific, recovery trajectories within the pain and medication, psycho-social and patient-reported outcomes domain.

METHODS

Prospective, observational study in participants greater than eighteen years of age. Data was collected prior to and up to one hundred and eighty days after completion of surgery within the three domains using PositiveTrends. Feasibility was assessed using participant response rates from the PositiveTrends app. Usability was assessed quantitatively using the System Usability Scale. Heat maps and effect plots were used to visualize multi-domain recovery trajectories. Generalized linear mixed effects models were used to estimate the change in the outcomes over time.

RESULTS

Forty-two participants were enrolled over a four-month recruitment period. Proportion of app responses was highest for participants who underwent spine surgery (median = 78, range = 36-100), followed by those who underwent knee arthroplasty (median = 72, range = 12-100), and hip arthroplasty (median = 62, range = 12-98). System Usability Scale mean score was 82 ± 16 at 180 days postoperatively. Function improved by 8 and 6.4 points per month after hip and knee arthroplasty, respectively. In spine participants, the Oswestry Disability Index decreased by 1.4 points per month. Mood improved in all three cohorts, however stress levels remained elevated in spine participants. Pain decreased by 0.16 (95% Confidence Interval: 0.13-0.20, p < 0.001), 0.25 (95% CI: 0.21-0.28, p < 0.001) and 0.14 (95% CI: 0.12-0.15, p < 0.001) points per month in hip, knee, and spine cohorts respectively. There was a 10.9-to-40.3-fold increase in the probability of using no medication for each month postoperatively.

CONCLUSIONS

In this study, we demonstrate the feasibility and usability of PositiveTrends, which can map and track multi-domain recovery trajectories after major arthroplasty or spine surgery.

How Are Patients Reviewing Spine Surgeons Online? A Sentiment Analysis of Physician Review Website Written Comments

STUDY DESIGN

A Sentiment Analysis of online reviews of spine surgeons.

OBJECTIVES

Physician review websites have significant impact on a patient's provider selection. Written reviews are subjective, but sentiment analysis through machine learning can quantitatively analyze these reviews. This study analyzes online written reviews of spine surgeons and reports biases associated with demographic factors and trends in words utilized.

METHODS

Online written and star-reviews of spine surgeons were obtained from healthgrades.com. A sentiment analysis package was used to analyze the written reviews. The relationship of demographic variables to these scores was analyzed with t-tests and word and bigram frequency analyses were performed. Additionally, a multiple regression analysis was performed on key terms.

RESULTS

8357 reviews of 480 surgeons were analyzed. There was a significant difference between the means of sentiment analysis scores and star scores for both gender and age. Younger, male surgeons were rated more highly on average (P < .01). Word frequency analysis indicated that behavioral factors and pain were the main contributing factors to both the best and worst reviewed surgeons. Additionally, several clinically relevant words, when included in a review, affected the odds of a positive review.

CONCLUSIONS

The best reviews laud surgeons for their ability to manage pain and for exhibiting positive bedside manner. However, the worst reviews primarily focus on pain and its management, as exhibited by the frequency and multivariate analysis. Pain is a clear contributing factor to reviews, thus emphasizing the importance of establishing proper pain expectations prior to any intervention.

Robotics and navigation in spine surgery: A narrative review

Introduction

In recent decades, there has been a rising trend of spinal surgical interventional techniques, especially Minimally Invasive Spine Surgery (MIS), to improve the quality of life in an effective and safe manner. However, MIS techniques tend to be difficult to adapt and are associated with an increased risk of radiation exposure. This led to the development of 'computer-assisted surgery' in 1983, which integrated CT images into spinal procedures evolving into the present day robotic-assisted spine surgery. The authors aim to review the development of spine surgeries and provide an overview of the benefits offered. It includes all the comparative studies available to date.

Methods

The manuscript has been prepared as per "SANRA-a scale for the quality assessment of narrative review articles". The authors searched Pubmed, Embase, and Scopus using the terms "(((((Robotics) OR (Navigation)) OR (computer assisted)) OR (3D navigation)) OR (Freehand)) OR (O-Arm)) AND (spine surgery)" and 68 articles were included for analysis excluding review articles, meta-analyses, or systematic literature.

Results

The authors noted that 49 out of 68 studies showed increased precision of pedicle screw insertion, 10 out of 19 studies show decreased radiation exposure, 13 studies noted decreased operative time, 4 out of 8 studies showed reduced hospital stay and significant reduction in rates of infections, neurological deficits, the need for revision surgeries, and rates of radiological ASD, with computer-assisted techniques.

Conclusion

Computer-assisted surgeries have better accuracy of pedicle screw insertion, decreased blood loss and operative time, reduced radiation exposure, improved functional outcomes, and lesser complications.

National spine surgery registries' characteristics and aims: globally accepted standards have yet to be met. Results of a scoping review and a complementary survey

BACKGROUND

Surgery involving implantable devices is widely used to solve several health issues. National registries are essential tools for implantable device surveillance and vigilance. In 2017, the European Union encouraged Member States to establish "registries and databanks for specific types of devices" to evaluate device safety and performance and ensure their traceability. Spine-implantable devices significantly impact patient safety and public health; spine registries might help improve surgical outcomes. This study aimed to map existing national spine surgery registries and highlight their features and organisational standards to provide an essential reference for establishing other national registries.

METHODS

A scoping search was performed using the Embase, PubMed/Medline, Scopus, and Web of Science databases for the terms "registry", "register", "implantable", and all terms and synonyms related to spinal diseases and national registries in publications from January 2000 to December 2020. This search was later updated and finalised through a web search and an ad hoc survey to collect further detailed information.

RESULTS

Sixty-two peer-reviewed articles were included, which were related to seven national spine registries, six of which were currently active. Three additional active national registries were found through the web search. The nine selected national registries were set up between 1998 and 2021. They collect data on the procedure and use patient-reported outcome measures (PROMs) for the follow-up.

CONCLUSION

Our study identified nine currently active national spine surgery registries. However, globally accepted standards for developing a national registry of spine surgery are yet to be established. Therefore, an international effort to increase result comparability across registries is highly advisable. We hope the recent initiative from the Orthopaedic Data Evaluation Panel (ODEP) to establish an international collaboration will meet these needs.

Incidence of Surgical Site Infection Following Lateral Lumbar Interbody Fusion Compared With Posterior/Transforaminal Lumbar Interbody Fusion: A Propensity Score-Weighted Study

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

The objective of this study was to compare the incidence of surgical site infection (SSI) after lateral lumbar interbody fusion (LLIF) and posterior/transforaminal lumbar interbody fusion ( P /TLIF).

SUMMARY OF BACKGROUND DATA

Previous studies have shown that LLIF can improve neurological symptoms to a comparable degree to P /TLIF. However, data on the risk of SSI after LLIF is lacking compared with P /TLIF.

MATERIALS AND METHODS

The study was conducted under a retrospective cohort design in patients undergoing LLIF or P /TLIF for lumbar degenerative diseases between 2013 and 2020 using a hospital administrative database. We used propensity score overlap weighting to adjust for confounding factors including age, sex, body mass index, comorbidities, number of fusion levels, hospital size, and surgery year. We estimated weighted odds ratios (ORs) and 95% CIs for SSI within 30 days postoperatively.

RESULTS

We compared the risk of SSI between 2874 patients who underwent LLIF and 24,245 patients who received P/TLIF Patients who had received LLIF were at significantly less risk of experiencing an SSI compared with those receiving P/TLIF (0.7% vs. 1.2%; weighted OR: 0.57; 95% CI: 0.36 -0.92; P=0.02). As a secondary outcome, patients who had received LLIF had less risk of transfusion (7.8% vs. 11.8%; weighted OR: 0.63; 95% CI:0.54 -0.73; P <0.001).

CONCLUSIONS

In this large retrospective cohort study of adults undergoing lumbar interbody fusion, LLIF was associated with a significantly lower risk of SSI than P /TLIF. The small, but significantly, decreased risk of SSI associated with LLIF may inform decisions regarding the technical approach for lumbar interbody fusion.

Incidence and treatment trends of infectious spondylodiscitis in South Korea: A nationwide population-based study

The incidence of infectious spondylodiscitis (IS) has increased in recent years due to an increase in the numbers of older patients with chronic diseases, as well as patients with immunocompromise, steroid use, drug abuse, invasive spinal procedures, and spinal surgeries. However, research focusing on IS in the general population is lacking. This study investigated the incidence and treatment trends of IS in South Korea using data obtained from the Health Insurance Review and Assessment Service. A total of 169,244 patients (mean age: 58.0 years) diagnosed from 2010 to 2019 were included in the study. A total of 10,991 cases were reported in 2010 and 18,533 cases in 2019. Hence, there was a 1.5-fold increase in incidence rate per 100,000 people from 22.90 in 2010 to 35.79 in 2019 (P < 0.05). The incidence rate of pyogenic spondylodiscitis per 100,000 people increased from 15.35 in 2010 to 33.75 in 2019, and that of tuberculous spondylodiscitis decreased from 7.55 in 2010 to 2.04 in 2019 (P < 0.05, respectively). Elderly individuals ≥ 60 years of age accounted for 47.6% (80,578 patients) of all cases of IS. The proportion of patients who received conservative treatment increased from 82.4% in 2010 to 85.8% in 2019, while that of patients receiving surgical treatment decreased from 17.6% to 14.2% (P < 0.05, respectively). Among surgical treatments, the proportions of corpectomy and anterior fusion declined, while proportion of incision and drainage increased (P < 0.05, respectively). The total healthcare costs increased 2.9-fold from $29,821,391.65 in 2010 to $86,815,775.81 in 2019 with a significant increase in the ratio to gross domestic product. Hence, this population-based cohort study demonstrated that the incidence rate of IS has increased in South Korea. The conservative treatment has increased, while the surgical treatment has decreased. The socioeconomic burden of IS has increased rapidly.

Cervical Steroid Injections Are Not Effective for Prevention of Surgical Treatment of Degenerative Cervical Myelopathy

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

The objective of this study is to determine how often patients with degenerative cervical myelopathy (DCM) and initially treated with cervical steroid injections (CSI) and to determine whether these injections provide any benefit in delaying ultimate surgical treatment.

METHODS

All patients with a new diagnosis of DCM, without previous cervical spine surgery or steroid injections, were identified in PearlDiver, a large insurance database. Steroid injection and surgery timing was identified using Current Procedural Terminology (CPT) codes. Multivariate logistic regression identified associations with surgical treatment.

RESULTS

A total of 686 patients with DCM were identified. Pre-surgical cervical spine steroid injections were utilized in 244 patients (35.6%). All patients underwent eventual surgical treatment. Median time from initial DCM diagnosis to surgery was 75.5 days (mean 351.6 days; standard deviation 544.9 days). Cervical steroid injections were associated with higher odds of surgery within 1 year (compared to patients without injections, OR = 1.44, P < .001) and at each examined time point through 5 years (OR = 2.01, P < .001). In multivariate analysis comparing injection types, none of the 3 injection types were associated with decreased odds of surgery within 1 month of diagnosis.

CONCLUSIONS

While cervical steroid injections continue to be commonly performed in patients with DCM, there is an overall increased odds of surgery after any type of cervical injection. Therefore injections should not be used to prevent surgical management of DCM.

Importance of computed tomography Hounsfield units in predicting S1 screw loosening after lumbosacral fusion

We investigated whether computed tomography (CT) Hounsfield unit (HU) values of the S1 screw trajectory can predict screw loosening after lumbosacral fixation. We analysed 102 patients (58 men and 44 women) who underwent L5-S1 interbody fusion between April 2018 and October 2019. We reviewed the characteristics of patients including body mass index, smoking, comorbidity with diabetes mellitus, and interbody fusion types. Bone mineral density (BMD) was obtained from the lumbar spine and total hip using dual-energy X-ray absorptiometry. Additionally, we reviewed the S1 screw lengths and diameters. HU values of both L1 vertebral bodies and bilateral S1 screw trajectories were measured on preoperative CT. At six months postoperatively, S1 screws on CT were assessed. Screws with a 1 mm or more radiolucent zone were defined as "loosening". Seventeen patients had loosened screws, and 85 patients did not. The patient characteristics did not significantly differ between the two groups. Both total hip BMD and L1 HU values were low in the loosening patient group (both p = 0.03). Of the 204 total S1 screws, 25 screws were loosened, and 179 screws were not. The screw length was short (p = 0.01), and the HU value of the S1 screw trajectory was low (p < 0.001) in the loosening screw group. Based on receiver operating characteristic analyses of these factors, the area under the curve of HU value of the S1 screw trajectory was the highest (0.79). Measuring the HU value of both the L1 vertebral body and S1 screw trajectory aids in predicting screw loosening.

Current Indications for Spinal Endoscopic Surgery and Potential for Future Expansion

Endoscopic spine surgery (ESS) has evolved as a safe, effective, and efficient alternative for minimally invasive spine surgery (MISS). The innovation of full-endoscopic systems makes definitive decompression surgery through different approaches feasible. The approach can be determined according to the location of the target lesion or the surgeon's preference. During the past 2 decades, ESS has expanded its indications from lumbar to cervical spines. Except for decompression, endoscopy-assisted fusion surgery is also developing. However, ESS is still evolving and has a steep learning curve. The revolution of technologies and ESS techniques will enable surgeons to treat various spinal diseases more practically. In recent years, the application of the computer-assisted navigation system and augmented reality have reformed imaging quality and interpretation. The endoscopic rhizotomy techniques have opened a new way for MISS of chronic low back pain. This review introduces the current indications of ESS and its potential future expansion.

Risk Stratification of Elderly Patients Undergoing Spinal Surgery Using the Modified Frailty Index

STUDY DESIGN

Retrospective cohort.

OBJECTIVES

To validate the 11-item modified Frailty Index (mFI) as a perioperative risk stratification tool in elderly patients undergoing spine surgery.

METHODS

All consecutive cases of spine surgery in patients aged 65 years or older between July 2016 and June 2018 at a state-wide trauma center were retrospectively reviewed. The primary outcome was post-operative major complication rate (Clavien-Dindo Classification ≥ III). Secondary outcome measures included the rate of all complications, 6-month mortality and surgical site infection.

RESULTS

A total of 348 cases were identified. The major complication rate was significantly lower in patients with an mFI of 0 compared to ≥ 0.45 (18.3% versus 42.5%, P = .049). As the mFI increased from 0 to ≥ 0.45 there was a stepwise increase in risk of major complications (P < .001). Additionally, 6-month mortality rate was considerably lower when the mFI was 0 rather than ≥ 0.27 (4.2% versus 20.4%, P = .007). Multivariate analysis demonstrated an mFI ≥ 0.27 was significantly associated with an increased incidence of major complication (OR 2.80, 95% CI 1.46-5.35, P = .002), all complication (OR 2.93, 95% CI 1.70-15.11, P < .001), 6-month mortality (OR 7.39, 95% CI 2.55-21.43, P < .001) and surgical site infection (OR 4.43, 95% CI 1.71-11.51, P = .002). The American Society of Anesthesiologists' (ASA) index did not share a stepwise relationship with any outcome.

CONCLUSION

The mFI is significantly associated in a gradated fashion with increased morbidity and mortality. Patients with an mFI ≥ 0.27 are at greater risk of major complications, all-complications, 6-monthy mortality, and surgical site infection.

Recommendations for enhanced post-surgical recovery in the spine (REPOC)

INTRODUCTION/OBJECTIVES

Enhanced recovery after surgery (ERAS) constitutes a multimodal approach, based on available scientific evidence, that achieves better patient's functionality, reduces pain, and even lowers financial costs. The present consensus statement proposes the standards for the implementation of ERAS programs to lumbar fusion surgery, a meant benchmark we call REPOC.

METHODOLOGY

A multidisciplinary group of experts was set up ad hoc to review consensus recommendations for lumbar arthrodesis, using the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) system.

RESULTS

As a result, 23 recommendations were selected throughout the preoperative, intraoperative, and postoperative phases of the surgical procedure. A 29-item checklist was also drawn up to implement REPOC protocols in spinal surgeries.

CONCLUSIONS

This list of recommendations will facilitate the implementation of this multimodal approach as a safe and effective tool for reducing adverse events in our environment.

[Translated article] Recommendations for enhanced post-surgical recovery in the spine (REPOC)

INTRODUCTION/OBJECTIVES

Enhanced recovery after surgery (ERAS) constitutes a multimodal approach, based on available scientific evidence, that achieves better patient's functionality, reduces pain, and even lowers financial costs. The present consensus statement proposes the standards for the implementation of ERAS programmes to lumbar fusion surgery, a meant benchmark we call REPOC.

METHODOLOGY

A multidisciplinary group of experts was set up ad hoc to review consensus recommendations for lumbar arthrodesis, using the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) system.

RESULTS

As a result, 23 recommendations were selected throughout the preoperative, intraoperative, and postoperative phases of the surgical procedure. A 29-item checklist was also drawn up to implement REPOC protocols in spinal surgeries.

CONCLUSIONS

This list of recommendations will facilitate the implementation of this multimodal approach as a safe and effective tool for reducing adverse events in our environment.

Comparison of discover cervical disc arthroplasty and anterior cervical discectomy and fusion for the treatment of cervical degenerative disc diseases: A meta-analysis of prospective, randomized controlled trials

Objective

This study aims to evaluate the clinical efficacy and safety between Discover cervical disc arthroplasty (DCDA) and anterior cervical discectomy and fusion (ACDF) in Cervical degenerative disc diseases.

Methods

Two researchers independently conducted a search of PubMed, EMBASE, and Cochrane Central Register of Controlled Trails (CENTRAL) for randomized controlled trials (RCTs) following the Cochrane methodology guidelines. A fixed-effects or random-effects model was applied based on different heterogeneity. Review Manager (Version 5.4.1) software was used to perform data analysis.

Results

A total of 8 RCT studies were included in this meta-analysis. The results indicate that the DCDA group had a higher incidence of reoperation (P = 0.03) and a lower incidence of ASD (P = 0.04) than the CDA group. There was no significant difference between two groups regarding NDI score (P = 0.36), VAS ARM score (P = 0.73), VAS NECK score (P = 0.63), EQ-5D score (P = 0.61) and dysphagia incidence (0.18).

Conclusion

DCDA and ACDF have similar results in terms of NDI scores, VAS scores, EQ-5D scores, and dysphagia. In addition, DCDA can reduce the risk of ASD but increases the risk of reoperation.

The impact of tobacco use on clinical outcomes and long-term survivorship after anatomic total shoulder arthroplasty

Introduction

Postoperative outcomes following total shoulder arthroplasty can be affected by preoperative health factors such as tobacco usage.

Methods

The charts of patients who underwent anatomic total shoulder arthroplasty were retrospectively analyzed and stratified based on smoking status. The primary data included range of motion and patient reported outcomes. Additionally, demographic, radiographic, and survivorship analyses were conducted. All data were analyzed using statistical inference.

Results

There were 78, 49, and 16 non-smoker, former smoker, and current smoker shoulders respectively with no significant differences in sex, American Society of Anesthesiologists status, body mass index, or mean follow-up time (average: 10.7 yrs). Smokers (51.5 ± 10.4 years) were younger than both non-smokers (64.9 ± 8.1 years; p < 0.01) and former smokers (65.1 ± 9.1years; p < 0.01) at the time of surgery. For non-smokers and former smokers, all range of motion and patient reported outcome scores significantly improved. Smokers reported significant improvements in all patient reported outcomes and external and internal rotation. Visual Analog Scale, American Shoulder and Elbow, and Simple Shoulder Test scores were lower for smokers comparatively, but these differences did not reach significance. Forward elevation was higher postoperatively for non-smokers (149.7o ± 17.2o) and former smokers (147.1o ± 26.0o) compared to current smokers (130.9o ± 41.2o; p = 0.017). No differences between the cohorts were found in the radiographic analysis. Revision rates were lower in the non-smoking cohort (7.7%) compared to both former (20.4%; p = 0.036) and current smokers (37.5%; p < 0.01). Survival curves showed that non-smoker implants lasted longer than those of current smokers.

Conclusion

After a decade, patients generally had improved shoulder range of motion, functionality, and pain regardless of smoking status. However, current smokers required shoulder replacements sooner and revision surgery more frequently.

Thoracolumbar Injury Classification and Severity Score Is Predictive of Perioperative Adverse Events in Operatively Treated Thoracic and Lumbar Fractures

STUDY DESIGN

A retrospective cohort study of patients with surgically treated thoracolumbar fractures.

PURPOSE

This study aimed to describe the incidence of adverse events (AEs) after surgical stabilization of thoracolumbar spine injuries and to identify predictive factors for the occurrence of AEs.

OVERVIEW OF LITERATURE

Thoracolumbar spine fractures are frequently present in patients with blunt trauma and are associated with significant morbidity. AEs can occur due to the initial spinal injury or secondary to surgical treatment. There is a lack of emphasis in the literature on the AEs that can occur after operative management of thoracolumbar fractures.

METHODS

We performed a retrospective review of 199 patients with surgically treated thoracolumbar fractures operated between January 2007 and January 2018. The potential risk factors for the development of AEs as well as the development of common complications were evaluated by univariate analysis, and a multivariate logistic regression analysis was performed to identify independent risk factors predictive of the above.

RESULTS

The overall rate of AEs was 46.7%; 83 patients (41.7%) had nonsurgical AEs, whereas 24 (12.1%) had surgical adverse events. The most common AEs were urinary tract infections in 43 patients (21.6%), and hospital-acquired pneumonia in 21 patients (10.6%). On multivariate logistic regression, a Thoracolumbar Injury Classification and Severity (TLICS) score of 8-10 (odds ratio [OR], 6.39; 95% confidence interval [CI], 2.33-17.51), the presence of polytrauma (OR, 2.64; 95% CI, 1.17-5.99), and undergoing open surgery (OR, 2.31; 95% CI, 1.09-4.88) were significant risk factors for AEs. The absence of neurological deficit was associated with a lower rate of AEs (OR, 0.47; 95% CI, 0.31-0.70).

CONCLUSIONS

This study suggests the presence of polytrauma, preoperative American Spinal Injury Association score, and TLICS score are predictive of AEs in patients with surgically treated thoracolumbar fractures. The results might also suggest a role for minimally invasive surgical methods in reducing AEs in these patients.

Prevalence, risk factors, and potential symptoms of hyponatremia after spinal surgery in elderly patients

Old age and spinal surgery significantly increase the risk of postoperative hyponatremia. However, detailed analyses of postoperative hyponatremia after spinal surgery in elderly patients are lacking. Therefore, we retrospectively reviewed the records of 582 consecutive patients aged > 60 years who underwent spinal surgery to evaluate the frequency, risk factors, and symptoms of postoperative hyponatremia after spinal surgery in the elderly population. Postoperative hyponatremia was defined as a postoperative blood sodium level < 135 meq/L at postoperative day (POD)1, POD3, and/or after POD6. A total of 92 (15.8%) patients showed postoperative hyponatremia. On a multivariate analysis, a diagnosis of a spinal tumor/infection, decompression and fusion surgery, and lower preoperative sodium levels were significant independent factors of postoperative hyponatremia (p = 0.014, 0.009, and < 0.001, respectively). In total, 47/92 (51%) cases could have been symptomatic; vomiting was noted in 34 cases (37%), nausea in 19 cases (21%), headache in 14 cases (15%), and disturbances in consciousness, including delirium, in ten cases (21%); all incidences of these symptoms were significantly higher in elderly patients with postoperative hyponatremia than in the matched control group without postoperative hyponatremia (p < 0.05, respectively). Additionally, the length of stay was 2 days longer in patients than in the matched controls (p = 0.002).

Is lumbosacral transitional vertebra associated with lumbar disc herniation in patients with low back pain?

PURPOSE

To evaluate lumbosacral transitional vertebrae (LSTV) frequency in patients with low back pain and lumbar disc herniation (LDH) and to analyze correlations between LSTV presence and intervertebral disc degeneration.

METHODS

This retrospective study included patients with low back pain applying between January 2021 and August 2021. Inclusion criteria were age of 18-65, presence of a standing lumbosacral Xray and a lumbar MRI taken within 2 weeks of the indexed symptoms. Patients with a history of spondylolisthesis, spondylodiscitis, scoliosis and vertebral neoplasia were excluded. A total of 1821 patients met the inclusion criteria. Radiographs and MRIs were evaluated by 2 radiologists.

RESULTS

Of all patients, 61.4% were female and the mean age was 43.2 ± 12.2. LDH was detected in 57.7% of patients while a LSTV was present in 43.3%. Sacralization and LSTV were significantly different between the patients with and without an LDH. Patients with LSTV had a higher incidence of a LDH affecting 3 or more intervertebral disc levels (p < 0.001). There was a significant difference in-between LSTV and non-LSTV groups regarding the M1 and M2 intervertebral disc degeneration levels.

CONCLUSION

A LDH is more common in the presence of a LSTV. Female sex is highly correlated with herniation. Three or more intervertebral disc levels are affected in the presence of an LSTV. Significantly higher degeneration incurs at the M1 and M2 intervertebral levels. Sacralization is a risk factors for a lumbar disc herniation.

The utility of the CADISS® system in the dissection of epidural fibrosis in revision lumbar spine surgery (A case series)

Spine surgery and spinal fusion surgery are rising. Revision rates following initial surgery are between 8 and 45%. Epidural fibrosis is a common response to spine surgery for most patients and increases complications in revision surgery. Previous research suggests using MESNA (Sodium 2-mercaptoethane sulfonate) in combination with mechanical blunt dissection safely reduces surgical complications. MESNA is a mucolytic agent which selectively cleaves disulphide bonds involved in the adherence and strength of fibrosis, meaning cutting instruments are not needed. The Chemically Assisted DISSection (CADISS®) System is an optimised non-cutting surgical device, consisting of a reconstitution cartridge for MESNA preparation, irrigated surgical instruments, and a footswitch to control MESNA release. This is the first study to investigate the use of the CADISS® System in revision spine surgery.

Methods

This was a prospective, open label, observational case study. We enrolled 21 patients for revision spine surgery with the CADISS® System at two Belgium sites. The primary assessment was the number of successful removals of epidural fibrosis without cutting. The amount of MESNA used, total dissection and procedure time were recorded. For secondary criterion, the surgeons assessed global satisfaction, facilitation of dissection, quickness of action, usability, bleeding reduction and visualisation of the cleavage plane using an 11-point Likert scale (0–10). Due to the exploratory nature, no formal statistical analysis was planned. We calculated the percentage and confidence interval of successful procedures, the medians and corresponding interquartile range of the Likert criterion, and the mean (±SD) of the amount of MESNA used, CADISS® dissection time and total procedure time.

Results

24 fibrosis dissections were performed in 19 patients and 23 were successful (95.8%, CI: 78.9%; 99.9%). The mean amount of MESNA used, mean dissection time and procedure time were 16 ml (±4.94), 16.5 min (±16.1) and 86.3 min (±25.1), respectively. No dural tears were reported. The mean global satisfaction score was 9.0 (8.0–9.0). All other Likert criterion had scores of 8.0 or 9.0, excluding quickness of action, which scored 7.0 (6.0–9.0).

Conclusions

The CADISS® System in revision spine surgery has potential to effectively reduce dissection complications.

•

Revision rates following initial surgery are between 8 and 45%. Epidural fibrosis is a common response to spine surgery for most patients and increases complications in revision surgery.

•

Previous research suggests using MESNA (Sodium 2-mercaptoethane sulfonate) in combination with mechanical blunt dissection safely reduces surgical complications. MESNA is a mucolytic agent which selectively cleaves disulphide bonds involved in the adherence and strength of fibrosis, meaning cutting instruments are not needed. The Chemically Assisted DISSection (CADISS®) System is an optimised non-cutting surgical device, consisting of a reconstitution cartridge for MESNA preparation, irrigated surgical instruments, and a footswitch to control MESNA release.

•

We enrolled 21 patients for revision spine surgery with the CADISS® System at two Belgium sites. The primary assessment was the number of successful removals of epidural fibrosis without cutting. The CADISS® System in revision spine surgery has potential to effectively reduce dissection complications.

Cefuroxime concentrations in the anterior and posterior column of the lumbar spine - an experimental porcine study

BACKGROUND CONTEXT

Surgical site infection following spine surgery is associated with increased morbidity and mortality. Perioperative antibiotic prophylaxis is a key factor in lowering the risk of acquiring an infection. Previous studies have assessed perioperative cefuroxime concentrations in the anterior column of the cervical spine with an anterior surgical approach. However, the majority of surgeries are performed in the posterior column and many surgeries involve the lumbar spine.

PURPOSE

The objective of this study was to compare the perioperative tissue concentrations of cefuroxime in the anterior and posterior column during lumbar spine surgery with a posterior surgical approach.

STUDY DESIGN

In vivo experimental pharmacokinetic study of cefuroxime concentrations in an acute preclinical porcine model.

METHODS

The lumbar vertebral column was exposed from L1 to L5 in 8 female pigs. Microdialysis catheters were placed for sampling in the anterior column (vertebral body) and posterior column (posterior arch) within the same vertebra (L5). Cefuroxime (1.5 g) was administered intravenously. Microdialysates and plasma samples were continuously obtained over 8 hours. Cefuroxime concentrations were quantified by Ultra High Performance Liquid Chromatography Tandem Mass Spectrometry. The primary endpoint was the time above the cefuroxime clinical breakpoint minimal inhibitory concentration (T>MIC) for Staphylococcus aureus of 4 µg/mL. The secondary endpoint was tissue penetration (AUC_tissue/AUC_plasma).

RESULTS

Mean T>MIC 4 µg/mL (95% confidence interval) was 123 min (105-141) in plasma, 97 min (79-115) in the anterior column and 93 min (75-111) in the posterior column. Tissue penetration (95% confidence interval) was incomplete for both the anterior column 0.48 (0.40-0.56) and posterior column 0.40 (0.33-0.48).

CONCLUSIONS

T>MIC was comparable between the anterior and posterior column. Mean cefuroxime concentrations decreased below the clinical breakpoint minimal inhibitory concentration for S. aureus of 4 µg/mL after 123 minutes (plasma), 97 minutes (anterior column) and 93 minutes (posterior column). This is shorter than the duration of most lumbar spine surgeries, and therefore alternative dosing regimens should be considered in posterior open lumbar spine surgeries lasting more than 1.5 hours.

CLINICAL SIGNIFICANCE

Open lumbar spine surgery often involves extensive soft tissue dissection, stripping and retraction of the paraspinal muscles which may impair the local blood flow exposing the lumbar vertebra to postoperative infections. A single intravenous administration of 1.5 g cefuroxime only provided sufficient prophylactic target tissue concentrations in the vertebra of the lumbar spine for up to 1.5 hours.

Comparison of three imaging and navigation systems regarding accuracy of pedicle screw placement in a sawbone model

3D-navigated pedicle screw placement is increasingly performed as the accuracy has been shown to be considerably higher compared to fluoroscopy-guidance. While different imaging and navigation devices can be used, there are few studies comparing these under similar conditions. Thus, the objective of this study was to compare the accuracy of two combinations most used in the literature for spinal navigation and a recently approved combination of imaging device and navigation system. With each combination of imaging system and navigation interface, 160 navigated screws were placed percutaneously in spine levels T11-S1 in ten artificial spine models. 470 screws were included in the final evaluation. Two blinded observers classified screw placement according to the Gertzbein Robbins grading system. Grades A and B were considered acceptable and Grades C-E unacceptable. Weighted kappa was used to calculate reliability between the observers. Mean accuracy was 94.9% (149/157) for iCT/Curve, 97.5% (154/158) for C-arm CBCT/Pulse and 89.0% for CBCT/StealthStation (138/155). The differences between the different combinations were not statistically significant except for the comparison of C-arm CBCT/Pulse and CBCT/StealthStation (p = 0.003). Relevant perforations of the medial pedicle wall were only seen in the CBCT group. Weighted interrater reliability was found to be 0.896 for iCT, 0.424 for C-arm CBCT and 0.709 for CBCT. Under quasi-identical conditions, higher screw accuracy was achieved with the combinations iCT/Curve and C-arm CBCT/Pulse compared with CBCT/StealthStation. However, the exact reasons for the difference in accuracy remain unclear. Weighted interrater reliability for Gertzbein Robbins grading was moderate for C-arm CBCT, substantial for CBCT and almost perfect for iCT.