Spinal versus general anesthesia for minimally invasive transforaminal lumbar interbody fusion: implications on operating room time, pain, and ambulation

The impact of spinal versus general anesthesia on the variability of surgical times: a systematic review and meta-analysis

BACKGROUND

With spinal anesthesia, when cases are taking longer than usual, there may be behavioural tendencies for surgical teams to work more quickly. We conducted a systematic review with meta-analysis to examine standard deviations of surgical times for single-dose spinal anesthetics versus general anesthesia. We compared ratios of mean surgical times as a secondary endpoint.

METHODS

We included randomized trials of humans where general or spinal anesthesia was used for one category of surgical procedure (e.g., hip arthroplasty) and the article reported the means and standard deviations of operative durations. We used statistical methods suitable for surgical times following log-normal distributions. We used generalized confidence intervals to calculate point estimates of ratios and standard errors for each study, followed by pooling among studies using DerSimonian and Laird random-effects meta-analysis with Knapp-Hartung adjustment.

RESULTS

Among the 77 included studies, 96% were of high quality for our endpoint (i.e., had a low risk of bias), as no (0%) study focused on comparing variability of surgical times and none had surgical time as the primary endpoint. Spinal anesthesia was associated with 6.6% smaller standard deviations than general anesthesia (95% confidence interval, 15.8% smaller to 1.9% larger, P = 0.13). By meta-regression, there was no significant association of the ratios of standard deviations with study quality (P = 0.39), year of publication (P = 0.76), or categories of procedures (all five P ≥ 0.28). Spinal anesthesia was associated with 1.1% smaller means than general anesthesia (95% confidence interval, 3.7% smaller to 1.5% larger, P = 0.42). There were no significant associations between the ratios of means and study quality (P = 0.47), year of publication (P = 0.95), or categories of procedures (all five, P ≥ 0.63).

CONCLUSIONS

The results of this systematic review and meta-analysis show with high confidence that the effect of choosing spinal anesthesia on variability in surgical time, if present, is sufficiently small to have no substantive direct economic effect. The same conclusion applies to mean surgical time. Therefore, although anesthetic choice has a clinical (biological) impact and affects anesthesia times, the direct effects on surgical times and workflow are minimal at most. Anesthetic choice does not influence operating theatre productivity via changes to surgical times. The impact of spinal anesthetic effects is limited to nonoperative times (e.g., reducing anesthesia-controlled times by using a block room before the patient enters the operating room).

STUDY REGISTRATION

PROSPERO ( CRD42023461952 ); first submitted 8 September 2023.

Spinal Anesthesia for Multilevel Awake Minimally Invasive Transforaminal Lumbar Interbody Fusion: Single-Center Experience

BACKGROUND AND OBJECTIVES

Awake minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) generates minimal surrounding tissue damage and has been shown to be a safe, time-effective, and cost-reductive technique in single-level procedures. The purpose of this study was to advocate for the utilization of multilevel MIS-TLIF even in challenging cases as it has demonstrated positive outcomes.

METHODS

Chart review was conducted for consecutive patients undergoing awake multilevel MIS-TLIF from 2020 to 2023. Various demographic, preoperative, and postoperative variables were collected and descriptively analyzed.

RESULTS

Sixteen patients underwent multilevel awake MIS-TLIF at our institution during the specified period. Among them, 87.5% underwent a two-level procedure and 12.5% a three-level procedure. The median age ± IQR was 69.5 ± 11 years, with a slight male predominance (56.25%). Common comorbidities included hypertension (56.25%), obesity (37.5%), sleep apnea (25%), and type 2 diabetes (18.75%). The American Society of Anesthesiologists risk was 2 in 43.75% of patients and 3 in 56.25%. All patients presented pain, and 12.5% showed motor deficit. Intraoperative data showed a median of 196 minutes in the operating room where 156 ± 27.75 minutes corresponded to actual procedure time. The median estimated blood loss was 50 ± 70 cc. In the immediate postoperative period, 1 patient had nausea and emesis, and 1 reported fatigue. The median pain score during this period was 4.6 ± 2.03. Pain control medications were required for various patients, with methocarbamol (50%), hydromorphone (37.5%), and oxycodone (25%) being the most commonly prescribed in the postanesthesia care unit. No patient had new neurological deficits after the surgical intervention. The median length of stay was 2 days ±1.25. All patients were discharged with no complications.

CONCLUSION

Multilevel awake MIS-TLIF emerges as a safe and effective technique for complex cases, enhancing patient quality of life with minimal blood loss and postoperative pain.

Spinal Anesthesia for Awake Spine Surgery: A Paradigm Shift for Enhanced Recovery after Surgery

Awake surgery has been applied for various surgical procedures with positive outcomes; however, in neurosurgery, the technique has traditionally been reserved for cranial surgery. Awake surgery for the spine (ASFS) is an alternative to general anesthesia (GA). As early studies report promising results, ASFS is progressively gaining more interest from spine surgeons. The history defining the range of adverse events facing patients undergoing GA has been well described. Adverse reactions resulting from GA can include postoperative nausea and vomiting, hemodynamic instability and cardiac complications, acute kidney injury or renal insufficiency, atelectasis, pulmonary emboli, postoperative cognitive dysfunction, or malignant hyperthermia and other direct drug reactions. For this reason, many high-risk populations who have typically been poor candidates under classifications for GA could benefit from the many advantages of ASFS. This narrative review will discuss the significant historical components related to ASFS, pertinent mechanisms of action, protocol overview, and the current trajectory of spine surgery with ASFS.

Efficacy and Advantages of Spinal Anesthesia in Lumbar Disk Surgery

BACKGROUND

 Quality of life (QoL) may be affected due to various reasons such as low back or leg pains with accompanying neurologic problems. Lumbar disk surgery is one of the most common performed surgeries to relieve those symptoms. Various anesthetic techniques can be used safely to perform lumbar disk surgeries. Properties that make an anesthetic technique good are mainly the quick onset and returning of the effects. This large retrospective study with patients who have undergone lumbar disk surgery under spinal anesthesia aims to evaluate the perioperative and postoperative parameters of the spinal anesthesia and review the literature.

METHODS

 Cases operated under spinal anesthesia between January 2017 and December 2020 were investigated, and 617 patients who underwent simple lumbar disk surgery were included in the study. Demographic characteristics and American Society of Anesthesiologists (ASA) physical status of the patients were recorded. Visual analog scale (VAS) and QoLscores were obtained before and after the operation.

RESULTS

 There were 282 (45.7%) male and 335 (54.3%) female patients with a mean age of 39.48 ± 16.71 years (range: 18-58 years) at symptom onset. The mean operating time was 46.3 minutes (range: 22-68 minutes). Average blood loss was 85 mL (range: 55-125 mL). All the patients were mobilized 6 to 12 hours after surgery. In our patient group, there were both high- and normal-risk groups in terms of the ASA physical status. During the clinical follow-up, a statistically significant improvement was found for the VAS and QoL scores (p < 0.05).

CONCLUSIONS

 In this large retrospective study, our results have confirmed that spinal anesthesia is at least comparable to general anesthesia and even superior to it in some aspects.

Utility of spinal anesthesia in plastic surgery and other surgical subspecialties: A literature review

INTRODUCTION

Spinal anesthesia (SA) is commonly used within the specialties of orthopedic surgery, obstetrics and gynecology, spine surgery, and general surgery, and offers several benefits over general anesthesia (GA). However, SA is used much less frequently in plastic surgery. This review analyzed currently existing data on SA use across various surgical specialties and compared the benefits and complications of SA to those of GA, to assess its utility and potential for more widespread use in plastic surgery.

METHODS

A comprehensive literature review was conducted using the PubMed and Cochrane Library databases to evaluate the utility of SA in plastic surgery. Indications, contraindications, and data on the use of SA across various surgical specialties were reviewed. Benefits, complications, and cost-effectiveness were also assessed. Finally, the utility of SA in plastic surgery was evaluated based on the available literature.

RESULTS

SA has been shown to yield several benefits and fewer risks than GA, including a higher possibility of early discharge, decreased costs, better pain and postoperative nausea and vomiting control, and decreased risk of deep venous thrombosis and pulmonary embolism.

CONCLUSION

Although commonly used for procedures across various surgical specialties such as obstetrics and gynecology, urology, and orthopedic surgery, SA is less frequently used within plastic surgery. Plastic surgery procedures that would benefit from the use of SA include those below the umbilicus such as liposuction, lower extremity procedures, and perineal procedures, and owing to its benefits, we recommend that SA be used more often within plastic surgery under appropriate clinical circumstances.

Current Status of Awake Spine Surgery: A Bibliometric Analysis

BACKGROUND

Spine surgery accounts for a large proportion of neurosurgical procedures, with approximately 313 million spine surgeries conducted annually worldwide. Considering delayed recovery and postoperative complications that are commonly reported, there has been a recent shift toward minimally invasive spine procedures conducted under local anesthesia. Despite proven success, there exists a limited body of literature on the use of awake surgery in spinal procedures.

METHODS

A bibliometric analysis was conducted to map the current landscape of work in this field. 190 articles were identified from the Web of Science (Clarivate, NY) database. A comprehensive bibliometric analysis was performed on a narrowed list of the most relevant articles using Bibliometrix, an R-based programming tool.

RESULTS

There has been a rise in academic papers published on the topic of awake spine surgery since 2016, with an increase in publication count by approximately 18% annually and each article cited approximately ten times on average to date. The year 2022 saw an uptick in publications, with 9 throughout the entire year. The most impactful article, with a total of 95 citations, was published by Sairyo et al.1 Thematic analysis revealed that the terms "lumbar spine" and "stenosis" are well-developed topics in the literature, whereas the topics of "complications," "fusion," and "cost-analysis" are less well-developed topics.

CONCLUSIONS

This study provides a comprehensive overview of the most-cited articles in the field of awake spine surgery. Specifically, it identifies areas that are well represented in the literature and those which are underrepresented and should be areas of continued future research.

Comparative outcomes of awake spine surgery under spinal versus general anesthesia: a comprehensive systematic review and meta-analysis

BACKGROUND

Awake surgery, under spinal anesthesia (SA), is an alternative to surgery under general anesthesia (GA), in neurological and spine surgery. In the literature, there seem to be some evidence supporting benefits associated with the use of this anesthetic modality, as compared to GA. Currently, there is a notable lack of updated and comprehensive review addressing the complications associated with both awake SA and GA in spine surgery. We hence aimed to perform a systematic review of the literature and meta-analysis on the topic.

METHODS

A systematic search was conducted to identify studies that assessed SA in spine surgery from database inception to April 14, 2023, in PubMed, Medline, Embase, and Cochrane databases. Outcomes of interest included estimated blood loss, length of hospital stay, operative time, and overall complications. Meta-analysis was conducted using random effects models.

RESULTS

In total, 38 studies that assessed 7820 patients were included. The majority of the operations that were treated with SA were single-level lumbar cases. Awake patients had significantly shorter lengths of hospital stay (Mean difference (MD): - 0.40 days; 95% CI - 0.64 to - 0.17) and operative time (MD: - 19.17 min; 95% CI - 29.68 to - 8.65) compared to patients under GA. The overall complication rate was significantly higher in patients under GA than SA (RR, 0.59 [95% CI 0.47-0.74]). Patients under GA had significantly higher rates of postoperative nausea/vomiting RR, 0.60 [95% CI 0.39-0.90]) and urinary retention (RR, 0.61 [95% CI 0.37-0.99]).

CONCLUSIONS

Patients undergoing awake spine surgery under SA had significantly shorter operations and hospital stays, and fewer rates of postoperative nausea and urinary retention as compared to GA. In summary, awake spine surgery offers a valid alternative to GA and added benefits in terms of postsurgical complications, while being associated with relatively low morbidity.

General Versus Nongeneral Anesthesia for Spinal Surgery: A Comparative National Analysis of Reimbursement Trends Over 10 Years

BACKGROUND AND OBJECTIVES

Nongeneral anesthesia (non-GA) spine surgery is growing in popularity and has facilitated earlier postoperative recovery, reduced cost, and fewer complications compared with spine surgery under general anesthesia (GA). Changes in reimbursement policies have been demonstrated to correlate with clinical practice; however, they have yet to be studied for GA vs non-GA spine procedures. We aimed to investigate trends in physician reimbursement for GA vs non-GA spine surgery in the United States.

METHODS

We queried the ACS-NSQIP for GA and non-GA (regional, epidural, spinal, and anesthesia care/intravenous sedation) spine surgeries during 2011-2020. Work relative value units per operative hour (wRVUs/h) were retrieved for decompression or stabilization of the cervical, thoracic, and lumbar spine. Propensity score matching (1:1) was performed using all baseline variables.

RESULTS

We included 474 706 patients who underwent spine decompression or stabilization procedures. GA was used in 472 248 operations, whereas 2458 operations were non-GA. The proportion of non-GA spine operations significantly increased during the study period. Operative times ( P < .001) and length of stays ( P < .001) were shorter in non-GA when compared with GA procedures. Non-GA lumbar procedures had significantly higher wRVUs/h when compared with the same procedures performed under GA (decompression; P < .001 and stabilization; P = .039). However, the same could not be said about cervicothoracic procedures. Lumbar decompression surgeries using non-GA witnessed significant yearly increase in wRVUs/h ( P < .01) contrary to GA ( P = .72). Physician reimbursement remained stable for procedures of the cervical or thoracic spine regardless of the anesthesia.

CONCLUSION

Non-GA lumbar decompressions and stabilizations are associated with higher and increasing reimbursement trends (wRVUs/h) compared with those under GA. Reimbursement for cervical and thoracic surgeries was equal regardless of the type of anesthesia and being relatively stable during the study period. The adoption of a non-GA technique relative to the GA increased significantly during the study period.

Spinal anesthesia for L5-S1 interlaminar endoscopic lumbar discectomy: a retrospective study

OBJECTIVE

This study aimed to report our experience with spinal anesthesia (SA) in patients undergoing L5-S1 interlaminar endoscopic lumbar discectomy (IELD) and clarify its advantages and disadvantages.

METHODS

One hundred twelve patients who underwent IELD for an L5-S1 disc herniation under SA were retrospectively analyzed. SA with 0.5% ropivacaine was administered using a 27-gauge fine needle. Intraoperatively, the volume and level of SA, surgical time, blood loss, and cardiopulmonary complications were documented. Postoperative data was collected included the number of patients who ambulated on the day of surgery, incidence of complications and were then statistically analyzed.

RESULTS

Analgesia was complete throughout the entire operation in all patients and no other adjuvant intraoperative analgesic drugs were needed. Mean visual analog scale scores for intraoperative and early postoperative (24 h) pain were 0 and 2.43 ± 1.66. SA was administered at the L3-4 interspace in 34 patients (30.4%) and the L2-3 interspace in 78 (69.6%). Administration was successful with the first attempt in all patients. Mean operation time was 70.12 ± 6.52 min. Mean intraoperative blood loss volume was 20.71 ± 5.26 ml. Ninety-eight patients ambulated on the same day as surgery. Mean length of hospital stay was 24.36 ± 3.64 h. Dural injury without damaging the nerve root occurred in one patient. One patient experienced recurrent disc herniation. Intraoperative hypotension and respiratory distress occurred in five (4.5%) and three (2.7%) patients, respectively. Three patients (2.7%) received postoperative analgesia therapy and two (1.8%) experienced nausea. Two patients (1.8%) developed urinary retention. Spinal headache, cauda equina syndrome, and neurotoxicity did not occur.

CONCLUSION

SA can achieve satisfactory pain control for patients undergoing IELD with a low incidence of adverse events. SA may be a useful alternative to local and general anesthesia for IELD surgery. Future randomized controlled trials are warranted to investigate.

Spinal anesthesia in elective lumbar spinal surgery

Spinal anesthesia (SA) is gaining recognition as a safe and efficacious regional alternative to general anesthesia for elective lumbar surgery. However, unfamiliarity with management issues related to its use has limited the adoption of awake spine surgery, despite its benefits. Few centers in the United States routinely offer SA for elective lumbar surgery, and a comprehensive workflow to standardize SA for lumbar surgery is lacking. In this article, we examine recent literature on the use of SA in lumbar surgery, review the experience of our institution with SA in lumbar surgery, and provide a cohesive outline to streamline the implementation of SA from the perspective of the anesthesiologist. We review the critical features of SA in contemporary lumbar surgery, including selection of patients, methods of SA, intraoperative sedation, and management of several important technical considerations. We aimed to flatten the learning curve to improve the availability and accessibility of the technique for eligible patients.

Awake Spinal Fusion Is Associated with Reduced Length of Stay, Opioid Use, and Time to Ambulation Compared to General Anesthesia: A Matched Cohort Study

OBJECTIVE

There is increasing interest in performing awake spinal fusion under spinal anesthesia (SA). Evidence supporting SA has been positive, albeit limited. The authors set out to investigate the effects of SA versus general anesthesia (GA) for spinal fusion procedures on length of stay (LOS), opioid use, time to ambulation (TTA), and procedure duration.

METHODS

The authors performed a retrospective review of a single surgeon's patients who underwent lumbar fusions under SA versus GA from June of 2020 to June of 2022. SA patients were compared to demographically matched GA counterparts undergoing comparable procedures. Analyzed outcomes include operative time, opioid usage in morphine milligram equivalents, TTA, and LOS.

RESULTS

Ten SA patients were matched to 10 GA counterparts. The cohort had a mean age of 66.77, a mean body mass index of 27.73 kg/m2, and a median American Society of Anesthesiologists Physical Status Score of 3.00. LOS was lower in SA versus GA patients (12.87 vs. 50.79 hours, P = 0.001). Opioid utilization was reduced in SA versus GA patients (10.76 vs. 31.43 morphine milligram equivalents, P = 0.006). TTA was reduced in SA versus GA patients (7.22 vs. 29.87 hours, P = 0.022). Procedure duration was not significantly reduced in SA patients compared to GA patients (139.3 vs. 188.2 minutes, P = 0.089).

CONCLUSIONS

These preliminary retrospective results suggest the use of SA rather than GA for lumbar fusions is associated with reduced hospital LOS, reduced opioid utilization, and reduced TTA. Future randomized prospective studies are warranted to determine if SA usage truly leads to these beneficial outcomes.

Regional anesthesia in spine surgery: A narrative review

Background: Regional anesthesia, which refers to the use of anesthetics to provide analgesia to a specific body part or nervous innervation territory, has become increasingly popular in the field of spine surgery. With the application of these techniques, it has been postulated that patients will require less systemic analgesia, intraoperatively and postoperatively. The authors of this narrative review discuss the common regional anesthetic modalities applied to spine surgery, in addition to patient selection criteria, success in patients with multiple comorbid illnesses, and its adoption by surgeons. Materials and Methods: An advanced search was performed in the PubMed database to obtain Englishlanguage articles discussing regional anesthesia, awake spine surgery, and postoperative complications. Articles were screened for relevance, and 47 articles were incorporated into this narrative review. Results: Classic neuraxial and paraspinal techniques have allowed surgeons to perform posterior decompression, fusion, and revision procedures. Transversus abdominus plane and quadratus lumborum blocks have enabled better pain control in patients undergoing surgeries requiring anterior or lateral approaches. Documented benefits of regional anesthesia include shorter operative time, improved pain control and hemodynamic stability, as well as decreased cost and length of stay. Several case series have demonstrated the success of these techniques in highly comorbid patients. Conclusion: Regional anesthesia provides an exciting opportunity to make surgical treatment possible for spine patients with significant comorbidities. Although additional randomized controlled trials are necessary to further refine patient selection criteria, current data demonstrates its safety and efficacy in the operating room.

Intraoperative Triggered Electromyography for Pedicle Screw Placement Under Spinal Anesthesia: A Preliminary Report

BACKGROUND

Triggered electromyography (tEMG) is an intraoperative neuromonitoring technique used to assess pedicle screw placement during instrumented fusion procedures. Although spinal anesthesia is a safe alternative to general anesthesia in patients undergoing lumbar fusion, its use may potentially block conduction of triggered action potentials or may require higher threshold currents to elicit myotomal responses when using tEMG. Given the broad utilization of tEMG for confirmation of pedicle screw placement, adoption of spinal anesthesia may be hindered by limited studies of its use alongside tEMG.

OBJECTIVE

To investigate whether spinal anesthesia affects the efficacy of tEMG, we compare the baseline spinal nerve thresholds during lumbar fusion procedures under general vs spinal anesthesia.

METHODS

Twenty-three consecutive patients (12 general and 11 spinal) undergoing single-level transforaminal lumbar interbody fusion were included in the study. Baseline nerve threshold was determined through direct stimulation of the spinal nerve using tEMG.

RESULTS

Baseline spinal nerve threshold did not differ between the general and spinal anesthesia cohorts (3.25 ± 1.14 vs 3.64 ± 2.16 mA, respectively; P = .949). General and spinal anesthesia cohorts did not differ by age, body mass index, American Society of Anesthesiologists score status, or surgical indication.

CONCLUSION

We report that tEMG for pedicle screw placement can be safely and effectively used in procedures under spinal anesthesia. The baseline nerve threshold required to illicit a myotomal response did not differ between patients under general or spinal anesthesia. This preliminary finding suggests that spinal anesthetic blockade does not contraindicate the use of tEMG for neuromonitoring during pedicle screw placement.

Current indications for spinal anesthesia-a narrative review

Spinal anesthesia is a commonly performed regional anesthesia technique by most anesthesiologists worldwide. This technique is learned early during training and is relatively easy to master. Despite being an old technique, spinal anesthesia has evolved and developed in various aspects. This review attempts to highlight the current indications of this technique. Understanding the finer aspects and knowledge gaps will help postgraduates and practicing anesthesiologists in designing patient-specific techniques and interventions.

Operative room time comparison between general and spinal anesthesia in total hip arthroplasty: an institutional study

PURPOSE

A relatively high expense with any procedure is total operative time; two components being the time spent anesthetizing the patient and time spent transferring the patient out of the operating room (OR). Both times can be affected by the anesthetic method used. This study compares different operative time intervals for both spinal anesthesia (SA) and general anesthesia (GA), in patients undergoing a primary total hip arthroplasty (THA), to identify the most appropriate and cost-effective anesthetic method.

METHODS

A retrospective chart review was performed at a single institution for primary total hip arthroplasty procedures performed in the year 2019. Primary THAs without complications performed by three orthopedic surgeons were selected. Anesthesia records for 200 patients were used to compare perioperative time intervals; 100 consecutive patients that received SA and 100 consecutive patients that received GA.

RESULTS

The time spent transferring the patient out of the operating room was 8 min for GA and 5 min for SA (p < 0.001). Total operative time for GA was 90 min and 87 min for SA (p = 0.3330). Total pre-operative time averaged 26 min in SA compared to 25 min in GA (p = 0.5874). Non-operative total time (all time components of patient interaction excluding surgery start to surgery finish) was significantly shorter in SA with an average of 52 compared to 56 in GA (p = 0.0151).

CONCLUSION

Time to transfer patient out of the OR and total non-operative time was significantly shorter in patients who received spinal anesthesia. These results and the complications of both general and spinal anesthesia should be taken into consideration when anesthetizing patients undergoing primary THA.

LEVEL OF EVIDENCE

III.

Assessment of surgeons' attitude towards awake spine surgery under spinal anesthesia

BACKGROUND

General anesthesia (GA) and spinal anesthesia (SA) have been adopted for lumbar spine surgery (LSS), but GA is used far more widely. We conducted a survey of spine surgeons to explore their attitudes and preferences regarding awake spine surgery under SA.

METHODS

A survey was emailed to 150 spine surgeons. Exposure and attitudes towards spine surgery under SA were elicited. A five-point Likert scale of agreement examined perceptions of SA, while attitudes towards SA were recorded by categorizing free text into themes.

RESULTS

Seventy-five surgeons completed the survey, 50 % response rate. Only 27 % said they perform LSS under SA. Most surgeons, 83 %, would recommend GA to a healthy patient undergoing lumbar laminectomy. Only 41 % believes SA to be as safe as GA, and only 30 % believes SA is associated with better postoperative pain control. The most common reasons why SA is not favored was lack of proven benefits over GA (65 %). When asked if a randomized trial finds SA to lead to less postoperative fatigue, 50 % said they would be more likely to offer SA, a significant increase from the baseline response of 27 % (p = 0.002).

CONCLUSIONS

Our survey indicates that the low adoption of SA for LSS is due to lack of surgeons' belief in the benefits of SA over GA, and that a randomized patient-centered trial has the potential of changing surgeons' perspective and increasing adoption of SA for LSS.

Two- versus multi-rod constructs for adult spinal deformity: A systematic review and Random-effects and Bayesian meta-analysis

BACKGROUND

Surgical approaches in adult spinal deformity are associated with high rates of adverse events including hardware failure and rod fracture. Recently, some reports have emerged comparing multiple-rod constructs with 2-rod constructs suggesting potential benefits with the former. However, these have been limited by variability in observed outcomes, which have limited the change of paradigm in adult spinal deformity surgery.

OBJECTIVE

To compare the rate of rod fracture, pseudoarthrosis, proximal junctional kyphosis and re-operation between 2-RC and M-RC.

METHODS

MEDLINE/Pubmed, Web of Science and Embase were searched without language restrictions for relevant articles from inception until October 2021. All observational cohort studies assessing patients with ADS undergoing 3-column osteotomy and comparing 2-RC with M-RC procedures on pseudarthrosis, rod fracture, kyphosis or reoperation were included. Data were independently extracted by 2 authors. Random-effects and Bayesian meta-analysis were used.

RESULTS

Six primary studies met inclusion criteria, yielding a total of 448 participants, with 223 receiving 2-RC and 225 M-RC. The random-effects meta-analysis pointed to a significantly lower risk of rod fracture associated with M-RC (RR = 0.43, 95 %CI = 0.28-0.66), with moderate heterogeneity being observed (I² = 20 %, p = 0.28). The random-effects meta-analysis pointed to a lower risk of pseudoarthrosis with M-RC than with 2-RC (RR = 0.49, CI = 0.28-0.84, to a lower rate of re-operation with M-RC than with 2-RC (RR = 0.52, CI = 0.28-0.97) and to a similar rate of proximal junctional kyphosis between 2-RC and M-RC patients (RR = 0.91, CI = 0.60-1.39). Low heterogeneity was observed for studies comparing pseudoarthrosis (I² = 9 %, p = 0.35), re-operation (I² = 0 %, p = 0.41) and proximal junctional kyphosis (I² = 0 %, p = 0.85).

DISCUSSION

These findings suggest that multiple rod-fracture constructs are associated with lower rates of rod fracture, re-operation rates, pseudoarthrosis but not proximal junctional kyphosis. Future studies should address the impact of other modulators of heterogeneity such as body mass index, metal alloys and length of the constructs.

Meta-Analysis of the Clinical Effect of MIS-TLF Surgery in the Treatment of Minimally Invasive Surgery of the Orthopaedic Spine

Minimally invasive surgery (MIS) has already had a significant impact on surgical treatment (spine). Because they are less invasive, minimally invasive treatments are often preferred over open spine surgery. MIS and open spine surgery in terms of posterior lumbar fusion (PLF), lumbar disc herniation (LDH), and cervical disc herniation (CDH) were all observational studies based on randomized controlled trials. Seventeen RCTs and six observational studies were conducted. Chemotherapy had no effect on the long-term alleviation of the neck or arm pain in patients with CDH. In LDH, MIS was superior in terms of pain relief, rehospitalization rates, and improvement in quality of life. At the expense of increased perioperative endoscopic, readmission, and revision rates, MIS achieved a significant reduction in 2-year expenditures, fewer medical problems, and improved Oswestry score ratings. There is no evidence to support the use of MIS over open surgery for lumbar or cervical process disc herniation. In comparison, MIS-TLIF has several advantages, in addition to lower revision/readmission rates. However, MIS significantly increases the surgeon's radiation exposure, regardless of the patient's sign. However, the effect on patients is unknown. These findings could help patients make better decisions when comparing open spine surgery to minimally invasive spine surgery, especially given how much advertising is out there for MIS.

Assessment of Patients' Willingness to Participate in a Randomized Trial of Spinal versus General Anesthesia for Lumbar Spine Surgery

BACKGROUND

Prospective nonrandomized studies have found less postoperative fatigue and improved quality of life in patients undergoing awake spine surgery under spinal anesthesia compared with general anesthesia. Randomized trials are needed to validate these findings.

OBJECTIVE

To prospectively investigate patients' willingness to enroll in randomized trials of lumbar spine surgery under spinal versus general anesthesia and identify any potential barriers.

METHODS

We recruited patients undergoing lumbar spine surgery for degenerative disease. We described a randomized trial of spine surgery under spinal versus general anesthesia and assessed patients' willingness to participate in such trial. We elicited preferences for treatment along with demographics. The association between these factors and willingness to participate in the trial was examined.

RESULTS

Fifty patients completed interviews; 58% were female, mean age of 60.9 ± 12.5 years. A total of 52% patients stated that they were definitely willing to participate in the hypothetical randomized trial, and 8% probably willing. Only 16% of patients were aware of spinal anesthesia as an option for low back surgery, and 60% indicated no strong preference for the anesthesia techniques. Patients without strong preferences stated a greater willingness to participate than those with strong preferences (80% vs. 10% definitely willing, P < 0.0001). Age, sex, education, work status, and race were not significantly associated with willingness to participate.

CONCLUSION

Sixty percent of patients stated that they were either definitely or probably willing to participate in the randomized trial. Subjects lacking strong preferences for the anesthesia technique stated a greater willingness to enroll than those with strong preference.

Bibliometric and Visualized Analyses of Research Studies on Different Analgesics in the Treatment of Orthopedic Postoperative Pain

Background

Pain following orthopedic surgery has always been a critical issue, which caused great distress to the patients. Analgesics in the treatment of postoperative pain following orthopedic surgery have aroused great attention from scholars, and numerous studies have been published in recent years. Bibliometrics could assist scholars in understanding the scope of research topics better, identifying research focuses and key literature, and analyzing the development and trend of analgesics in the treatment of postoperative pain following orthopedic surgery.

Methods

Literature data were retrieved from the Science Citation Index Expanded (SCI-E) of Web of Science (WOS) Core collection database. The articles from 1992 to December 2021 on analgesics in the treatment of postoperative pain following orthopedic surgery were recruited. The citation reports including the publication numbers, h-index, total citations, and average citations in terms of authors, organizations, and countries were obtained. Top 20 research directions, funds, and journals with the most publications were charted. The co-authorship relations in the analysis units of authors, organizations, and countries were analyzed by the online bibliometric tool and VOSviewer software. The author's keywords co-occurrence overlay map was visualized by the VOSviewer software.

Results

A total of 406 articles were retrieved from 1992 to December 4th, 2021, with 11,655 times cited, average citations of 28.57 per item, and an h-index of 55. The most high-yield publication year, authors, organizations, countries, research directions, funds, and journals were 2020 (n = 887), Ilfeld BM from University of California San Diego (n = 7), University of California System (n = 21), the USA (n = 178), Anesthesiology (n = 161), National Institutes of Health (NIH), USA, and United States Department of Health Human Services (n = 12), and Anesthesia and Analgesia (n = 29), respectively. Similarly, co-authoring analysis of publications regarding on different analgesics showed that the authors and countries with the most co-authorship strength were Carr Daniel B (total link strength = 6) and the USA (total link strength = 30), respectively. The highest occurrence keywords were “postoperative pain” with 135 occurrences (total link strength = 784). The future research hotspots might be “acute pain,” “outcomes,” “oxycodone,” “total hip,” “replacement,” and “United States.”

Conclusion

Analgesics in the treatment of postoperative pain following orthopedic surgery can be observed in this study by employing the online bibliometric tool and VOSviewer software, which established the relationship between the units of analysis. It can provide a meaningful resource with detailed information for orthopedic surgeons who would like to understand the trend in this field better. They can also benefit from the emphasis on citation count to carry out high-level research in the future.