Systematic Review of Outcomes Following 10-Year Mark of Spine Patient Outcomes Research Trial for Intervertebral Disc Herniation

Automatic segmentation of spine x-ray images based on multiscale feature enhancement network

BACKGROUND

Automatic segmentation of vertebrae in spinal x-ray images is crucial for clinical diagnosis, case analysis, and surgical planning of spinal lesions.

PURPOSE

However, due to the inherent characteristics of x-ray images, including low contrast, high noise, and uneven grey scale, it remains a critical and challenging problem in computer-aided spine image analysis and disease diagnosis applications.

METHODS

In this paper, a Multiscale Feature Enhancement Network (MFENet), is proposed for segmenting whole spinal x-ray images, to aid doctors in diagnosing spinal-related diseases. To enhance feature extraction, the network incorporates a Dual-branch Feature Extraction Module (DFEM) and a Semantic Aggregation Module (SAM). The DFEM has a parallel dual-branch structure. The upper branch utilizes multiscale convolutional kernels to extract features from images. Employing convolutional kernels of different sizes helps capture details and structural information at different scales. The lower branch incorporates attention mechanisms to further optimize feature representation. By modeling the feature maps spatially and across channels, the network becomes more focused on key feature regions and suppresses task-irrelevant information. The SAM leverages contextual semantic information to compensate for details lost during pooling and convolution operations. It integrates high-level feature information from different scales to reduce segmentation result discontinuity. In addition, a hybrid loss function is employed to enhance the network's feature extraction capability.

RESULTS

In this study, we conducted a multitude of experiments utilizing dataset provided by the Spine Surgery Department of Henan Provincial People's Hospital. The experimental results indicate that our proposed MFENet demonstrates superior segmentation performance in spinal segmentation on x-ray images compared to other advanced methods, achieving 92.61 ± 0.431 for MIoU, 92.42 ± 0.329 for DSC, and 99.51 ± 0.037 for Global_accuracy.

CONCLUSIONS

Our model is able to more effectively learn and extract global contextual semantic information, significantly improving spinal segmentation performance, further aiding doctors in analyzing patient conditions.

Multi-investigator collaboration in orthopedic surgery research compared to other medical fields: Update comparing 2021-2009

The purpose of this study was to assess the prevalence of multicenter studies in the orthopedic literature compared to general medicine and other surgical subspecialty studies as an update to a previous study. The number of multicenter research studies across three orthopedic surgery journals was higher in 2021 compared to 2009 (7.2% [95% CI: 5.1%-9.4%, χ2 [df = 1 = 43.8]], p < 0.0001), as was the number of authors and institutions listed on clinical research studies. While these trends in multicenter research publishing are encouraging, orthopedic surgery still lags behind the general medicine and other surgical subspecialty literature bases. Of the 934 orthopedic surgery studies published, 92 (9.9%) were multicenter studies compared to 64.4% of the general medicine and 26.9% of the other surgical subspecialty studies (χ2 [df = 2] = 472.6, p < 0.001). Multicenter trials conducted in orthopedics have fundamentally changed musculoskeletal care, affecting the lives of millions of patients. Participation in multicenter research should be encouraged and prioritized through continued advocacy, funding, support, and direction from orthopedic governing bodies, journals, and subspecialty groups.

Impact of unplanned readmissions on lumbar surgery outcomes: a national study of 33,447 patients

BACKGROUND CONTEXT

Unplanned readmissions following lumbar spine surgery have immense clinical and financial implications. However, little is known regarding the impact of unplanned readmissions on patient-reported outcomes (PROs) following lumbar spine surgery.

PURPOSE

To evaluate the impact of unplanned readmissions, including specific readmission reasons, on patient reported outcomes 12 months after lumbar spine surgery.

STUDY DESIGN/SETTING

A retrospective cohort study of prospectively collected data was conducted using patients included in the lumbar module of the Quality and Outcomes Database (QOD), a national, multicenter spine registry.

PATIENT SAMPLE

A total of 33,447 patients who underwent elective lumbar spine surgery for degenerative diseases were included. Mean age was 59.8 (SD=14.04), 53.6% were male, 89.5% were white, 45.9% were employed, and 47.5% had private insurance.

OUTCOME MEASURES

Unplanned 90-day readmissions and 12-month patient-reported outcomes (PROs) including numeric rating scale (NRS) scores for back and leg pain, Oswestry Disability Index (ODI) scores, EuroQol-5 Dimension (EQ-5D) scores, and North American Spine Society (NASS) patient-satisfaction scores.

METHODS

The lumbar module of the QOD was queried for adults undergoing elective lumbar spine surgery for degenerative disease. Unplanned 90-day readmissions were classified into 4 groups: medical, surgical, pain-only, and no readmissions. Medical and surgical readmissions were further categorized into primary reason for readmission. 12-month PROs assessing patient back and leg pain (NRS), disability (ODI), quality of life (EQ-5D), and patient satisfaction were collected. Multivariable models predicting 12-month PROs were built controlling for covariates.

RESULTS

A total of 31,430 patients (94%) had no unplanned readmission while 2,017 patients (6%) had an unplanned readmission within 90 days following lumbar surgery. Patients with readmissions had significantly worse 12-month PROs compared with those with no unplanned readmissions in covariate-adjusted models. Using Wald-df as a measure of predictor importance, surgical readmissions were associated with the worst 12-month outcomes, followed by pain-only, then medical readmissions. In separate covariate adjusted models, we found that readmissions for pain, SSI/wound dehiscence, and revisions were among the most important predictors of worse outcomes at 12-months.

CONCLUSIONS

Unplanned 90-day readmissions were associated with worse pain, disability, quality of life, and greater dissatisfaction at 12-months, with surgical readmissions having the greatest impact, followed by pain-only readmissions, then medical readmissions. Readmissions for pain, SSI/wound dehiscence, and revisions were the most important predictors of worse outcomes. These results may help providers better understand the factors that impact outcomes following lumbar spine surgery and promote improved patient counseling and perioperative management.

Effectiveness of intra-venous steroids for preventing surgery for lumbo-sacral radiculopathy secondary to intervertebral disc herniation: a retrospective study of 213 patients

The natural history of lumbar disc herniation with radiculopathy is favorable, with 95% of patients expected to be pain-free within 6 months of onset. Despite the favorable prognosis, operative treatment is often chosen by patients unable to “ride out” the radicular episode. Prospective studies comparing surgical with non-surgical treatment have demonstrated similar long-term results. We conducted a retrospective case-series study of patients with a lumbar disc herniation and intractable radicular pain without significant neurological deficits treated with intra-venous dexamethasone. The primary outcome measure was whether the patient had undergone operative treatment within 1 year of receiving the intravenous steroid treatment. 213 patients met our inclusion criteria. 30 were lost to follow-up and 2 had died before completing 1 year of follow-up. Of the remaining 181 patients, 133 (73.48%) had not undergone surgery within 1 year of receiving intra-venous steroid treatment while 48 (26.51%) had undergone surgery. 6 (3.31%) of the patients had undergone surgery more than 1 year of receiving IV steroid treatment. Intravenous steroid treatment in our retrospective series was approximately 30% better at preventing the need for surgery than the reported outcomes of conservative treatment in randomized controlled trials previously published.

Microdiscectomy Is More Cost-effective Than a 6-Month Nonsurgical Care Regimen for Chronic Radiculopathy

BACKGROUND

A recent randomized controlled trial (RCT), performed by the authors, comparing early surgical microdiscectomy with 6 months of nonoperative care for chronic lumbar radiculopathy showed that early surgery resulted in improved outcomes. However, estimates of the incremental cost-utility ratio (ICUR), which is often expressed as the cost of gaining one quality-adjusted life year (QALY), of microdiscectomy versus nonsurgical management have varied. Radiculopathy lasting more than 4 months is less likely to improve without surgical intervention and may have a more favorable ICUR than previously reported for acute radiculopathy.

QUESTION/PURPOSE

In the setting of chronic radiculopathy caused by lumbar disc herniation, defined as symptoms and/or signs of 4 to 12 months duration, is surgical management more cost-effective than 6 months of nonoperative care from the third-party payer perspective based on a willingness to pay of less than CAD 50,000/QALY?

METHODS

A decision analysis model served as the vehicle for the cost-utility analysis. A decision tree was parameterized using data from our single-center RCT that was augmented with institutional microcost data from the Ontario Case Costing Initiative. Bottom-up case costing methodology generates more accurate cost estimates, although institutional costs are known to vary. There were no major surgical cost drivers such as implants or bone graft substitutes, and therefore, the jurisdictional variance would be minimal for tertiary care centers. QALYs derived from the EuroQoL-5D were the health outcome and were derived exclusively from the RCT data, given the paucity of studies evaluating the surgical treatment of lumbar radiculopathy lasting 4 to 12 months. Cost-effectiveness was assessed using the ICUR and a threshold of willingness to pay CAD 50,000 (USD 41,220) per QALY in the base case. Sensitivity analyses were performed to account for the uncertainties within the estimate of cost utility, using both a probabilistic sensitivity analysis and two one-way sensitivity analyses with varying crossover rates after the 6-month nonsurgical treatment had concluded.

RESULTS

Early surgical treatment of patients with chronic lumbar radiculopathy (defined as symptoms of 4 to 12 months duration) was cost-effective, in that the cost of one QALY was lower than the CAD 50,000 threshold (note: the purchasing power parity conversion factor between the Canadian dollar (CAD) and the US dollar (USD) for 2019 was 1 USD = 1.213 CAD; therefore, our threshold was USD 41,220). Patients in the early surgical treatment group had higher expected costs (CAD 4118 [95% CI 3429 to 4867]) than those with nonsurgical treatment (CAD 2377 [95% CI 1622 to 3518]), but they had better expected health outcomes (1.48 QALYs [95% CI 1.39 to 1.57] versus 1.30 [95% CI 1.22 to 1.37]). The ICUR was CAD 5822 per QALY gained (95% CI 3029 to 30,461). The 2-year probabilistic sensitivity analysis demonstrated that the likelihood that early surgical treatment was cost-effective was 0.99 at the willingness-to-pay threshold, as did the one-way sensitivity analyses.

CONCLUSION

Early surgery is cost-effective compared with nonoperative care in patients who have had chronic sciatica for 4 to 12 months. Decision-makers should ensure adequate funding to allow timely access to surgical care given that it is highly likely that early surgical intervention is potentially cost-effective in single-payer systems. Future work should focus on both the clinical effectiveness of the treatment of chronic radiculopathy and the costs of these treatments from a societal perspective to account for occupational absences and lost patient productivity. Parallel cost-utility analyses are critical so that appropriate decisions about resource allocation can be made.

LEVEL OF EVIDENCE

Level III, economic and decision analysis.

Burden of preoperative opioid use and its impact on healthcare utilization after primary single level lumbar discectomy

BACKGROUND CONTEXT

The complication profile and higher cost of care associated with preoperative opioid use and spinal fusion is well described. However, the burden of opioid use and its impact in patients undergoing lumbar discectomy is not known. Knowledge of this, especially for a relatively benign and predictable procedure will be important in bundled and value-based payment models.

PURPOSE

To study the burden of pre-operative opioid use and its effect on postoperative healthcare utilization, cost, and opioid use in patients undergoing primary single level lumbar discectomy.

STUDY DESIGN

Retrospective cohort study.

PATIENT SAMPLE

A 29,745 patients undergoing primary single level lumbar discectomy from the IBM MarketScan (2000-2018) database.

OUTCOME MEASURES

Ninety-day and 1-year utilization of lumbar epidural steroid injections, emergency department (ED) services, lumbar magnetic resonance imaging, hospital readmission, and revision lumbar surgery. Continued opioid use beyond 3-months postoperatively until 1-year was also studied. We have reported costs associated with healthcare utilization among opioid groups.

METHODS

Patients were categorized in opioid use groups based on the duration and number of oral prescriptions before discectomy (opioid naïve, < 3-months opioid use, chronic preoperative use, chronic preoperative opioid use with 3-month gap before surgery, and other). The risk of association of preoperative opioid use with outcome measures was studied using multivariable logistic regression analysis with adjustment for various demographic and clinical variables.

RESULTS

A total of 29,745 patients with mean age of 45.3±9.6 years were studied. Pre-operatively, 29.0% were opioid naïve, 35.0% had < 3-months use and 12.0% were chronic opioid users. There was a significantly higher rate of post-operative lumbar epidural steroid injections, magnetic resonance imaging , ED visits, readmission and revision surgery within 90-days and 1-year after surgery in chronic pre-operative opioid users as compared with patients with < 3-months use and opioid naïve patients (p<.001). Chronic post-operative opioid use was present in 62.6% of the preoperative chronic opioid users as compared with 5.6% of patients with < 3-months opioid use. A 3-month prescription free period before surgery in chronic pre-operative opioid users cut the incidence of chronic post-operative opioid use by more than half, at 25.7%. Cost of care and adjusted analysis of risk have been described.

CONCLUSION

Chronic preoperative opioid use was present in 12% of a national cohort of lumbar discectomy patients. Such opioid use was associated with significantly higher post-operative healthcare utilization, risk of revision surgery, and costs at 90-days and 1-year postoperatively. Two-third of chronic preoperative opioid users had continued long-term postoperative opioid use. However, a 3-month prescription free period before surgery in chronic opioid users reduces the risk of long-term postoperative use. This data will be useful for patient education, pre-operative opioid use optimization, and risk-adjustment in value-based payment models.

The role of percutaneous neurolysis in lumbar disc herniation: systematic review and meta-analysis

BACKGROUND

Recalcitrant disc herniation may result in chronic lumbar radiculopathy or sciatica. Fluoroscopically directed epidural injections and other conservative modalities may provide inadequate improvement in some patients. In these cases, percutaneous neurolysis with targeted delivery of medications is often the next step in pain management.

METHODS

An evidence-based system of methodologic assessment, namely, the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) was used. Multiple databases were searched from 1966 to January 2021. Principles of the best evidence synthesis were incorporated into qualitative evidence synthesis. The primary outcome measure was the proportion of patients with significant pain relief and functional improvement (≥ 50%). Duration of relief was categorized as short-term (< 6 months) and long-term (≥ 6 months).

RESULTS

This assessment identified one high-quality randomized controlled trial (RCT) and 5 moderate-quality non-randomized studies with an application of percutaneous neurolysis in disc herniation. Overall, the results were positive, with level II evidence.

CONCLUSIONS

Based on the present systematic review, with one RCT and 5 nonrandomized studies, the evidence level is II for percutaneous neurolysis in managing lumbar disc herniation.

A challenging playing field: Identifying the endogenous impediments to annulus fibrosus repair

Intervertebral disc (IVD) herniations, caused by annulus fibrosus (AF) tears that enable disc tissue extrusion beyond the disc space, are very prevalent, especially among adults in the third to fifth decade of life. Symptomatic herniations, in which the extruded tissue compresses surrounding nerves, are characterized by back pain, numbness, and tingling and can cause extreme physical disability. Patients whose symptoms persist after nonoperative intervention may undergo surgical removal of the herniated tissue via microdiscectomy surgery. The AF, however, which has a poor endogenous healing ability, is left unrepaired increasing the risk for re-herniation and pre-disposing the IVD to degenerative disc disease. The lack of understanding of the mechanisms involved in native AF repair limits the design of repair systems that overcome the impediments to successful AF restoration. Moreover, the complexity of the AF structure and the challenging anatomy of the repair environment represents a significant challenge for the design of new repair devices. While progress has been made towards the development of an effective AF repair technique, these methods have yet to demonstrate long-term repair and recovery of IVD biomechanics. In this review, the limitations of endogenous AF healing are discussed and key cellular events and factors involved are highlighted to identify potential therapeutic targets that can be integrated into AF repair methods. Clinical repair strategies and their limitations are described to further guide the design of repair approaches that effectively restore native tissue structure and function.