Association of Untreated Pre-surgical Depression With Pain and Outcomes After Spinal Surgery.

STUDY DESIGN: Prospective Cohort Study. OBJECTIVE: Untreated pre-surgical depression may prolong post-surgical pain and hinder recovery. However, research on the impact of untreated pre-surgical depression on post-spinal surgery pain is lacking. Therefore, this study aimed to assess pre-surgical depression in patients and analyze its relationship with post-surgical pain and overall post-surgical outcomes. METHODS: We recruited 100 patients scheduled for lumbar spine surgery due to spondylolisthesis, degenerative lumbar disc diseases, and herniated lumbar disc diseases. Psychiatrists evaluated them for the final selection. We assessed the Beck Depression Inventory (BDI), Japanese Orthopaedic Association (JOA), Oswestry Disability Index (ODI), and EuroQoL 5 Dimensions (EQ-5D) scores, numerical back and leg pain scales, and medication dosage data collected before and at 6 weeks, 3 months, and 6 months after surgery. RESULTS: Ninety-one patients were included in this study; 40 and 51 were allocated to the control and depression groups, respectively. The pre- and post-surgical leg pain, back pain, and functional scores were not different. However, the depression group showed higher ODI and EQ-5D and lower JOA scores than the control group 3 months post-surgery. Partial correlation analysis revealed an inverse correlation between the JOA and BDI scores and a positive correlation between the EQ-5D and BDI scores at 3 months postoperatively. CONCLUSION: Untreated depression can prolong postoperative pain and hinder recovery. Detecting and treating depression in patients before spine surgery may improve their overall quality of life and functional recovery.

Accelerated Fusion Dynamics by Recombinant Human Bone Morphogenetic Protein-2 Following Transforaminal Lumbar Interbody Fusion, Particularly in Osteoporotic Conditions.

BACKGROUND CONTEXT: Early fusion is crucial in interbody procedures to minimize mechanical complications resulting from delayed union, especially for patients with osteoporosis. Bone morphogenetic proteins (BMPs) are used in spinal fusion procedures; however, limited evaluation exists regarding time-to-fusion for BMP use, particularly in patients with osteoporosis. PURPOSE: To evaluate the difference in time-to-fusion after single-level transforaminal lumbar interbody fusion (TLIF) surgery between recombinant human bone morphogenetic protein-2 (rhBMP-2) usage and non-usage groups according to bone density. STUDY DESIGN: Retrospective single-center cohort study PATIENT SAMPLE: This study enrolled 132 patients (mean age, 65.25±8.66; male patients, 40.9%) who underwent single-level TLIF for degenerative disorders between February 2012 and December 2021, with pre- and postoperative computed tomography (CT). OUTCOME MEASURE: The interbody fusion mass and bone graft status on postoperative CT scans was obtained annually, and time-to-fusion was recorded for each patient. METHODS: The patients were divided into two groups based on rhBMP-2 use during the interbody fusion procedure. Patients were further divided into osteoporosis, osteopenia, and normal groups based on preoperative L1 vertebral body attenuation values, using cutoffs of 90 and 120 Hounsfield units. It was strictly defined that fusion is considered complete when a trabecular bone bridge was formed, and therefore, the time-to-fusion was measured in years. Time-to-fusion was statistically compared between BMP group and non-BMP groups, followed by further comparison according to bone density. RESULTS: The time-to-fusion differed significantly between BMP and non-BMP groups, with half of the patients achieving fusion within 2.5 years in the BMP group compared with 4 years in the non-BMP group (p < 0.001). The fusion rate varied based on bone density, with the maximum difference observed in the osteoporosis group, when half of the patients achieved fusion within 3 years in the BMP group compared to 5 years in the non-BMP group (p < 0.001). Subgroup analysis was conducted, revealing no significant associations between time-to-fusion and factors known to influence the fusion process, including age, gender, medical history, smoking and alcohol use, and medication history, except for rh-BMP2 use and bone density. CONCLUSIONS: RhBMP-2 usage significantly reduced time-to-fusion in single-level TLIF, especially in patients with osteoporosis. LEVEL OF EVIDENCE: Level III.

Effect of saline irrigation temperature difference on postoperative acute pain and hypothermia during biportal endoscopic spine surgery.

BACKGROUND: Recently, enhanced recovery after surgery (ERAS) protocols have attracted attention; they emphasize on avoiding intraoperative hypothermia while performing lumbar fusion surgery. However, none of the studies have reported the protocol for determining the temperature of saline irrigation during biportal endoscopic spine surgery (BESS) procedure. This study evaluated the effectiveness of warm saline irrigation during BESS in acute postoperative pain and inflammatory reactions. MATERIALS AND METHODS: Fifty-five patients who underwent BESS procedure were retrospectively analyzed for the incidence of perioperative hypothermia (< 36oC), postoperative inflammatory factors (white blood cells (WBC), erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), interleukin-6 (IL-6), serum amyloid A (SAA)), and clinical outcomes (back visual analog scale (VAS) score, postoperative shivering). The patients were divided into the warm and cold saline irrigation groups. RESULTS: Hemoglobin, WBC, ESR, creatine kinase, and creatine kinase-muscle brain levels did not significantly differ between the warm and cold saline groups. The mean CRP, IL-6, and SAA levels were significantly higher in the cold saline group than in the warm saline group (p = 0.0058, 0.0028, and 0.0246, respectively); back VAS scores were also higher with a statistically significant difference until two days postoperatively (p < 0.001). During the entire procedure, the body temperature was significantly lower in the cold saline irrigation group, but the hypothermia incidence rate significantly differed 30 min after the operation was started. CONCLUSIONS: Using warm saline irrigation during BESS is beneficial for early recovery after surgery, as it is associated with reduced postoperative pain and complication rates.

Long-Term Incidence of Adjacent Segmental Pathology After Minimally Invasive vs. Open Transforaminal Lumbar Interbody Fusion.

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: To compare the incidence of adjacent segmental pathology (ASP) following minimally invasive (MI) vs open transforaminal lumbar interbody fusion (TLIF) and to identify factors linked to ASP requiring reoperation. METHODS: This retrospective study reviewed the outcomes of patients who underwent MI-TLIF or open TLIF. Radiographic ASP (RASP) was evaluated using X-ray imaging to distinguish between degenerative changes, spondylolisthesis, and instability in the adjacent spinal segment. Clinical ASP (CASP) was assessed with the visual analog scale score for leg and back pain and the Oswestry disability index. Patient data were collected 1, 2, 5, and 10 years postoperatively. The timing and frequency of ASP reoperation were analyzed. RESULTS: Five years postoperatively, the RASP rate was 35.23% and 45.95% in the MI-TLIF and open TLIF groups. The frequency of CASP differed significantly between the MI-TLIF and open TLIF groups at 1 year postoperatively. The rates of RASP, CASP, and ASP necessitating reoperation were not significantly different 10 years postoperatively. Cranial facet violation significantly affected ASP in both groups. In the open TLIF group, preoperative adjacent segment disc degeneration significantly influenced ASP. CONCLUSION: The RASP rate at 5 years postoperatively and the CASP rate at 1 year postoperatively differed significantly between groups. There was no difference in the rate of ASP requiring reoperation. Cranial facet violation is a crucial driving factor for ASP after both surgical procedures.

Proximity Between Screw and Endplate of Upper Instrumented Vertebra Using a Cortical Bone Trajectory Screw can Increase Radiographic Adjacent Segment Degeneration Risks in Patients With Lumbar Spinal Stenosis.

STUDY DESIGN: Retrospective observational study. OBJECTIVE: To determine the proximity between screw and endplate of the upper instrumented vertebra (UIV) using a cortical bone trajectory (CBT) screw as a predictive factor for radiographic adjacent segment degeneration (ASD) in patients surgically treated with transforaminal lumbar interbody fusion (TLIF) with CBT screws (CBT-TLIF) with lumbar spinal stenosis. SUMMARY OF BACKGROUND DATA: The risk factors for radiographic ASD after CBT-TLIF remain unknown. METHODS: Among patients surgically treated with CBT-TLIF at a single institute, 239 consecutive patients (80 males and 159 females) were enrolled. ASD was defined by the presence of one or more of the following three radiologic criteria on the adjacent segment: >3 mm anteroposterior translation, >10° segmental kyphosis, or >50% loss of disc height comparing immediate postoperative and 1-year follow-up radiographs. Clinical and radiological features associated with the development of ASD were retrospectively measured. Univariate and multivariate analyses were performed to identify risk factors associated with radiographic ASD. RESULTS: Radiographic ASD was observed in 71 (29.7%) cases at 1-year postoperative follow-up. The preoperative Pfirrmann grade of the adjacent segment (>grade 2), multi-level fusion (>2 levels), and proximity between the tip of CBT screws and endplate on the UIV were significantly associated with radiographic ASD (OR = 3.98, 95% CI [1.06-15.05], P=0.042 versus OR = 3.03, 95% CI [1.00-9.14], P=0.049 versus OR = 0.53, 95% CI [0.40-0.72], P<0.001). The cut-off value of the distance between the tip of the screw and endplate on UIV for radiographic ASD was approximately 2.5 mm (right-sided CBT screw; cut-off value 2.48 mm/ left-sided CBT screw; cut-off value 2.465 mm). CONCLUSION: Radiographic adjacent segment degeneration progression can occur when the cortical trajectory bone screw is close to the endplate of the upper instrumented vertebrae in patients with lumbar spinal stenosis undergoing fusion surgery.

Risk Factors and Characteristics of In-Hospital Falls After Spine Surgery: A Retrospective, Single-Center Cohort Study in the Republic of Korea.

Background: Falls after orthopaedic surgery can cause serious injuries, which lengthen hospital stays and increase medical expenses. This has prompted hospitals to implement various fall-prevention protocols. The aims of this study were to determine the incidence of in-hospital falls after spine surgery, to analyze the overall risk factors, to discern factors that have a major influence on falls, and to evaluate the effectiveness of the fall-prevention protocol that we implemented. Methods: This was a retrospective, single-center study including patients who underwent spine surgery from January 2011 to November 2021 at the National Health Insurance Service Ilsan Hospital (NHISIH) in Goyang, Republic of Korea. Reported falls among these patients were examined. Patient demographics; surgery type, date, and diagnosis; and fall date and time were evaluated. Results: Overall, 5,317 spine surgeries were performed, and 128 in-hospital falls were reported (overall incidence: 2.31%). From the multivariable analyses, older age and American Society of Anesthesiologists (ASA) score were identified as independent risk factors for in-hospital patient falls (multivariable adjusted hazard ratio [aHR] for age 70 to 79 years, 1.021 [95% confidence interval (CI), 1.01 to 1.031]; for age ≥80 years, 1.035 [1.01 to 1.06]; and for ASA score of 3, 1.02 [1.01 to 1.031]). Similar results were seen in the subgroup who underwent primary surgery. Within 2 weeks following surgery, the highest frequency of falls occurred at 3 to 7 days postoperatively. The lowest fall rate was observed in the evening (6 to 10 p.m.). Morbidities, including rib, spine, and extremity fractures, were recorded for 14 patients, but none of these patients underwent operative treatment related to the fall. The NHISIH implemented a comprehensive nursing care service in May 2015 and a fall protocol in May 2017, but the annual incidence rate did not improve. The fall rate was higher after thoracolumbar surgeries (2.47%) than after cervical surgeries (1.20%). Moreover, a higher fall rate was observed in thoracolumbar cases with a greater number of fusion levels and revision spine surgeries. Conclusions: Patients with advanced age, more comorbidities, a greater number of fusion levels, and revision surgeries and who are female are more vulnerable to in-hospital falls after spine surgery. Novel strategies that target these risk factors are warranted. Level of Evidence: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Effectiveness of Toothbrushing Technique for Biofilm Removal and Postoperative Infection Control after Spinal Fusion Surgery: A Retrospective Study.

This retrospective study was designed to investigate the effectiveness of using a toothbrush, which is commonly used in our daily life, for biofilm removal and infection control in the treatment of spinal infections occurring after spinal fusion surgery. Currently, a biofilm is thought to form on the surface of the metal inserted during spine fusion surgery. We aim to determine the differences in clinical outcomes between using and not using a toothbrush to remove biofilm while performing conventional drainage, curettage, and debridement. A total of 1081 patients who underwent anterior or posterior spinal fusion surgery between November 2018 and October 2022 were screened. The study included 60 patients who developed surgical site infection and underwent incision and drainage surgery either with a toothbrush (n = 20) or without a toothbrush (n = 40). Failure of infection control that requires revision surgery occurred in 2 patients (10%) in the Toothbrush group and in 14 patients (35%) in the No-Toothbrush group (p = 0.039). Thus, the rate of additional surgery was significantly lower in the Toothbrush group. Additionally, normalization of c-reactive protein levels occurred significantly faster in the Toothbrush group (p = 0.044). Therefore, using a toothbrush to treat spinal infections following spinal fusion surgery appears to have beneficial mechanical debridement effects, resulting in improved clinical results, which were also confirmed based on the electron microscopic images.

The Clinical Use of Osteobiologic and Metallic Biomaterials in Orthopedic Surgery: The Present and the Future.

As the area and range of surgical treatments in the orthopedic field have expanded, the development of biomaterials used for these treatments has also advanced. Biomaterials have osteobiologic properties, including osteogenicity, osteoconduction, and osteoinduction. Natural polymers, synthetic polymers, ceramics, and allograft-based substitutes can all be classified as biomaterials. Metallic implants are first-generation biomaterials that continue to be used and are constantly evolving. Metallic implants can be made from pure metals, such as cobalt, nickel, iron, or titanium, or from alloys, such as stainless steel, cobalt-based alloys, or titanium-based alloys. This review describes the fundamental characteristics of metals and biomaterials used in the orthopedic field and new developments in nanotechnology and 3D-printing technology. This overview discusses the biomaterials that clinicians commonly use. A complementary relationship between doctors and biomaterial scientists is likely to be necessary in the future.

A Comparative Analysis of Bi-Portal Endoscopic Spine Surgery and Unilateral Laminotomy for Bilateral Decompression in Multilevel Lumbar Stenosis Patients.

The clinical and radiological results before and after surgery were compared and analyzed for patients with multilevel lumbar stenosis who underwent bi-portal endoscopic spine surgery (BESS) and microscopic unilateral laminotomy for bilateral decompression (ULBD). We retrospectively identified 47 and 49 patients who underwent BESS and microscopic ULBD, respectively, who were diagnosed with multi-level lumbar stenosis. Clinical outcomes were evaluated using the visual analog scale score for both back and leg pain, and medication (pregabalin) use and Oswestry Disability Index (ODI) scores for overall treatment outcomes were used pre-operatively and at the final follow-up. Radiological outcomes were evaluated as the percentage of dura expansion volume, and percentage preservation of both facets and both lateral recess angles. The follow-up period of patients was about 17.04 months in the BESS group and about 16.90 months in the microscopic ULBD group. The back and leg visual analog scale (VAS) scores and average pregabalin use decreased more significantly in the BESS group than in the microscopic ULBD group (each p-value 0.0443, <0.001, 0.0378). All radiological outcomes were significantly higher in the BESS group than in the ULBD group. The change in ODI in two-level spinal stenosis showed a significantly higher value in the BESS group compared to the microscopic ULBD group (p-value 0.0335). Multilevel decompression with the BESS technique in multiple spinal stenosis is an adequate technique as it shows better clinical and radiological results than microscopic ULBD during a short-term follow-up period.

A Comparison Between Cortical Bone Trajectory Screws And Traditional Pedicle Screws in Patients With Single-Level Lumbar Degenerative Spondylolisthesis: Five-Year Results.

STUDY DESIGN: A retrospective observational study. OBJECTIVE: This study investigated the clinical and radiological results of using cortical bone trajectory (CBT) screws versus traditional pedicle (TP) screws in transforaminal lumbar interbody fusion (TLIF) during a five-year follow-up of patients with single-level lumbar degenerative spondylolisthesis. SUMMARY OF BACKGROUND DATA: Few studies have compared five-year follow-up outcomes between CBT screws and TP screws in TLIF. MATERIALS AND METHODS: We reviewed outcome data of patients with single-level lumbar degenerative spondylolisthesis who underwent TLIF procedures with CBT screws (131 patients) or TP screws (80 patients) between 2011 and 2015. Patient-reported clinical outcome data included Oswestry disability index scores and visual analog scale (VAS) scores for back and leg pain at baseline, six months, and one year, two years, and five years postoperatively. The radiographic fusion rate and prevalence of secondary surgery for adjacent segment disease were also measured. RESULTS: During the follow-up over five years, the CBT group had significantly lower VAS scores for back pain ( P <0.0001, respectively). At two years after surgery, the CBT group had significantly higher VAS scores for leg pain ( P =0.007). At five years postoperatively, no significant differences existed in the VAS score for leg pain or in the Oswestry disability index score between the two groups. Radiographic fusion rates (CBT vs. TP: 95.5% vs. 95.9%; P =0.881) and adverse events during the five years after surgery were not significantly different. At two years postoperatively, the prevalence of secondary surgery to treat adjacent segment disease was significantly different between the two groups (CBT vs . TP: 13.7% vs. 5.0%; P =0.044). CONCLUSIONS: Our results suggest that, during a five-year followup, CBT screws for TLIF were an effective treatment compared to TP screws in the setting of single-level lumbar degenerative spondylolisthesis. However, when using CBT screws for TLIF, surgeons should consider the higher rate of secondary procedures to treat symptomatic adjacent segment disease.

Lumbar Spinal Stenosis: Review Update 2022.

Patients with lumbar spinal stenosis (LSS) may experience neuropathic symptoms, such as back pain, radiating pain, and neurogenic claudication. Although the long-term outcomes of both nonsurgical and surgical treatments are similar, surgery may provide shortterm benefits, including improved symptoms and lower risk of falling. Decompression is mainly used for surgical treatment, and depending on the decompression degree and associated instability, combination therapy may be given. Minimally invasive surgery has been demonstrated to produce excellent results in the treatment of LSS. Thus, an approach aimed at understanding the overall pathophysiology and treatment methods of LSS is expected to have a better therapeutic effect.

Comparing the efficacy and safety of minimally invasive biportal endoscopic spine surgery versus conventional microscopic discectomy in single-level lumbar herniated intervertebral disc (ENDO-BH Trial): a multicenter, prospective, randomized controlled equivalence trial study protocol.

BACKGROUND: Biportal endoscopic surgery has recently been performed in lumbar discectomy, with advantages over conventional surgery, such as less skin scarring and muscle damage. However, the clinical results have not been established. Although previous studies reported no difference between the biportal endoscopic and microscopic discectomy clinical results, the evidence was weak. Therefore, this study aims to evaluate the efficacy and safety of the biportal endoscopic discectomy versus the microscopic discectomy. METHODS: This prospective multicenter randomized controlled equivalence trial is designed to compare the efficacy and safety outcomes of patients who underwent lumbar discectomy using biportal endoscopy or microscopy. We will include 100 participants (50 per group) with a lumbar herniated disc. The primary outcome will be the Oswestry Disability Index (ODI) score 12 months after surgery based on a modified intention-to-treat strategy. The secondary outcomes will include the visual analog scale score for low back and lower extremity radiating pain, the ODI score, the Euro-Qol-5-Dimensions score, surgery satisfaction, walking time, postoperative return to daily life period, postoperative surgical scar, and surgery-related variables, such as postoperative drainage, operation time, admission duration, postoperative creatine kinase, and implementation status of conversion to open surgery. Radiographic outcomes will also be analyzed using magnetic resonance imaging (MRI) or computed tomography (CT) and simple radiographs. Safety will be assessed by evaluating all adverse and severe adverse events and surgery-related effects. The participants will be assessed by a blinded assessor before surgery (baseline) and 2 weeks and 3, 6, and 12 months after surgery. DISCUSSION: This trial will be the first prospective, multicenter, randomized controlled trial to analyze the efficacy and safety of biportal endoscopic discectomy in lumbar herniated disc. This trial is designed for evaluating the equivalence of the results between biportal endoscopic and microscopic discectomy including adequate sample size, blinded analyses, and prospective registration to reduce bias. This trial will provide enough data on the effectiveness and safety of biportal endoscopic surgery and will be an important study that allows clear conclusions. TRIAL REGISTRATION: Clinical Research Information Service (cris.nih.go.kr.) ( KCT0006191 ). Registered on 27 March 2021.

Evaluation of the efficacy and safety of conventional and biportal endoscopic decompressive laminectomy in patients with lumbar spinal stenosis (ENDO-B trial): a protocol for a prospective, randomized, assessor-blind, multicenter trial.

BACKGROUND: Recent studies on biportal endoscopic spine surgery in patients with lumbar spinal stenosis have reported good clinical results. However, these studies have been limited by the small sample sizes and use of a retrospective study design. Therefore, we aim to compare the efficacy and safety of biportal endoscopic decompressive laminectomy with those of conventional decompressive laminectomy in a multicenter, prospective, randomized controlled trial. METHODS: This study will include 120 patients (60 per group, aged 20-80 years) with 1- or 2-level lumbar spinal stenosis, who will be recruited from six hospitals. The study will be conducted from July 2021 to December 2024. The primary outcome (Oswestry Disability Index at 12 months after surgery) will be evaluated through a modified intention-to-treat method. The secondary outcomes will include the following: visual analog scale score for low back and lower extremity radiating pain, EuroQol 5-dimensions score, surgery satisfaction, walking time, postoperative return to daily life period, postoperative surgical scars, and some surgery-related variables. Radiographic outcomes will be analyzed using magnetic resonance imaging or computed tomography. All outcomes will be evaluated before the surgery and at 2 weeks, 3 months, 6 months, and 12 months postoperatively. This protocol adheres to the Standard Protocol Items: Recommendations for Interventional Trials (SPIRIT) guidelines for reporting of clinical trial protocols. DISCUSSION: It is hypothesized that the efficacy and safety of biportal endoscopic and conventional decompressive laminectomy will be comparable in patients with lumbar spinal stenosis. The results of this trial will provide a high level of evidence for the efficacy and safety of the biportal endoscopic technique in patients with lumbar spinal stenosis and facilitate the development of clinical practice guidelines. Furthermore, the results of this study may indicate the feasibility of the biportal endoscopic technique for other types of spinal surgery. TRIAL REGISTRATION: The ENDO-B trial is registered at Clinical Research Information Service (CRIS, cris.nih.go.kr ) (KCT0006057; April 52,021).

Risk of reoperation and infection after percutaneous endoscopic lumbar discectomy and open lumbar discectomy : a nationwide population-based study.

AIMS: Open discectomy (OD) is the standard operation for lumbar disc herniation (LDH). Percutaneous endoscopic lumbar discectomy (PELD), however, has shown similar outcomes to OD and there is increasing interest in this procedure. However despite improved surgical techniques and instrumentation, reoperation and infection rates continue and are reported to be between 6% and 24% and 0.7% and 16%, respectively. The objective of this study was to compare the rate of reoperation and infection within six months of patients being treated for LDH either by OD or PELD. METHODS: In this retrospective, nationwide cohort study, the Korean National Health Insurance database from 1 January 2007 to 31 December 2018 was reviewed. Data were extracted for patients who underwent OD or PELD for LDH without a history of having undergone either procedure during the preceding year. Individual patients were followed for six months through their encrypted unique resident registration number. The primary endpoints were rates of reoperation and infection during the follow-up period. Other risk factors for reoperation and infection were also evalulated. RESULTS: Out of 549,531 patients, 522,640 had undergone OD (95.11%) and 26,891 patients had undergone PELD (4.89%). Reoperation rates within six months were 2.28% in the OD group, and 5.38% in the PELD group. Infection rates were 1.18% in OD group and 0.83% in PELD group. The risk of reoperation was lower for patients with OD than for patients with PELD (adjusted hazard ratio (HR) 0.38). The risk of infection was higher for patients with OD than for patients undergoing PELD (HR, 1.325). CONCLUSION: Compared with the OD group, the PELD group showed higher reoperation rates and lower infection rates. Cite this article: Bone Joint J 2021;103-B(8):1392-1399.

Predicting postoperative complications in patients undergoing lumbar spinal fusion by using the modified five-item frailty index and nutritional status.

AIMS: As the population ages and the surgical complexity of lumbar spinal surgery increases, the preoperative stratification of risk becomes increasingly important. Understanding the risks is an important factor in decision-making and optimizing the preoperative condition of the patient. Our aim was to determine whether the modified five-item frailty index (mFI-5) and nutritional parameters could be used to predict postoperative complications in patients undergoing simple or complex lumbar spinal fusion. METHODS: We retrospectively reviewed 584 patients who had undergone lumbar spinal fusion for degenerative lumbar spinal disease. The 'simple' group (SG) consisted of patients who had undergone one- or two-level posterior lumbar fusion. The 'complex' group (CG) consisted of patients who had undergone fusion over three or more levels, or combined anterior and posterior surgery. On admission, the mFI-5 was calculated and nutritional parameters collected. RESULTS: Complications occurred in 9.3% (37/396) of patients in the SG, and 10.1% (19/167) of patients in the CG. In the SG, the important predictors of complications were age (odds ratio (OR) 1.036; p = 0.002); mFI-5 (OR 1.026 to 2.411, as score increased to 1 ≥ 2 respectively; p = 0.023); albumin (OR 11.348; p < 0.001); vitamin D (OR 2.185; p = 0.032); and total lymphocyte count (OR 1.433; p = 0.011) . In the CG, the predictors of complications were albumin (OR 9.532; p = 0.002) and vitamin D (OR 3.815; p = 0.022). CONCLUSION: The mFI-5 and nutritional status were effective predictors of postoperative complications in the SG, but only nutritional status was successful in predicting postoperative complications in the CG. The complexity of the surgery, as well as the preoperative frailty and nutritional status of patients, should be considered when determining if it is safe to proceed with lumbar spinal fusion. Cite this article: Bone Joint J 2020;102-B(12):1717-1722.

Assessing changes in cervical epidural pressure during biportal endoscopic lumbar discectomy.

OBJECTIVE: Biportal endoscopic spinal surgery has been performed for several years, and its effectiveness is well known; however, no studies on its safety, specifically intracranial pressure, have been conducted to date. The authors sought to evaluate the effect of biportal endoscopic lumbar discectomy on intracranial pressure by monitoring cervical epidural pressure (CEP) changes throughout the procedure. METHODS: Twenty patients undergoing single-level biportal endoscopic lumbar discectomy were enrolled in this study. CEPs were monitored throughout the procedure, consisting of phase 1, establishing the surgical portal and working space; phase 2, performing decompression and discectomy; and phase 3, turning off the fluid irrigation system. After discectomy was completed, the authors evaluated changes in CEP as the irrigation pressure increased serially by adding phase 4, increasing irrigation pressure with outflow open; and phase 5, increasing irrigation pressure with outflow closed. RESULTS: The mean baseline CEP was measured as 16.65 mm Hg. In phase 1, the mean CEP was 17.3 mm Hg, which was not significantly different from the baseline CEP. In phase 2, the mean CEP abruptly increased up to 35.1 mm Hg when the epidural space was first connected with the working space, followed by stabilization of the CEP at 31.65 mm Hg. In phase 4, the CEP increased as the inflow pressure increased, showing a linear correlation, but not in phase 5. No patients experienced neurological complications. CONCLUSIONS: It is important to ensure that irrigation fluid is not stagnant and is maintained continuously. More attention must be paid to keeping pressures low when opening the epidural space.

Incidence & Risk Factors of Postoperative Delirium After Spinal Surgery in Older Patients.

Although postoperative delirium is a common complication in older patients, few papers have described risk factors after of spinal surgery. The purpose of this study was to analyze various perioperative risk factors for delirium after spinal surgery in older patients. This study was performed on retrospective data collection with prospective design. We analyzed 138 patients over 65 years of age who underwent spinal surgery. Preoperative factors were cognitive function (Mini-Mental State Examination-Korean (MMSE-K) and the Korean version of the Delirium Rating Scale-Revised-98 (K-DRS 98)), age, sex, type of admission, American Society of Anesthesiologist classification, metabolic equivalents, laboratory findings, visual analog scale, and Oswestry Disability Index. Intraoperative factors were operation time, blood loss, and type of procedure. Postoperative factors were blood transfusion and type of postoperative pain control. Postoperative delirium developed in 25 patients (18.16%). Patients were divided into two groups: Group with delirium (group A) and group without delirium (group B). MMSE-K scores in Group A were significantly lower than in Group B (p < 0.001). K-DRS 98 scores were significantly higher in Group A than Group B (p < 0.001). The operation time was longer in Group A than Group B (p = 0.059). On multivariate regression analysis, the odds ratio of K-DRS 98 was 2.43 (p = 0.010). After correction for the interaction between age and MMSE-K, patients younger than 73 years old had a significantly lower incidence of delirium with higher MMSE-K score (p = 0.0014). Older age, low level of preoperative cognitive function, long duration of surgery, and transfusion were important risk factors of postoperative delirium after spinal surgery. It is important to recognize perioperative risk factors and manage appropriately.

Transforaminal epidural steroid injections in cervical spinal disease with moderate to severe disability: Comparative study in patients with or without surgery.

Despite many clinical trials on cervical epidural steroid injections, the indications for and long-standing outcomes of this treatment remain controversial. We evaluated the outcomes and indications for transforaminal cervical epidural steroid injection (TCESI) in patients with moderate to severe disability.We prospectively gathered data from patients with 1 or 2-level cervical degenerative disease (herniated disc, foraminal stenosis) with moderate to severe disability (3.5 < initial visual analog scale < 6.5, 15 < Neck Disability Index < 35) and greater than 12 weeks of pain, despite conservative treatment. Patients with persistent disability and those who desired surgical intervention underwent decompression surgery. The clinical and demographic characteristics were compared between groups.Of the 309 patients who underwent TCESI, 221 (72%) did not receive surgical treatment during the 1-year follow-up period. The remaining 88 patients (28%) underwent surgery at a mean of 4.1 months after initial TCESI. Patients who underwent injection alone showed a significant decrease in disability and pain that persisted until the 1-year follow-up visit (P < .05). In patients who underwent surgery, the mean disability and pain scores after injection did not decrease for several months, although the scores significantly decreased up to 1 year after surgery (P < .05).The TCESI significantly decreased pain and disability in the moderate to severe disability group up to 1 year after injection. We recommend cervical TCESI as an initial treatment with moderate to severe disability patients.

Spinal epidural abscess successfully treated with biportal endoscopic spinal surgery.

Surgical decompression and antibiotic therapy are the treatments of choice for patients with spinal epidural abscess (SEA). Surgical treatment included decompression, evacuation of abscess, and debridement. Recently, minimal invasive surgery has been introduced more widely, and biportal endoscopic spinal surgery have shown satisfactory clinical outcomes compared with traditional open surgery. The purpose of this study was to evaluate the efficacy of biportal endoscopic spinal surgery for the treatment of SEA .From January 2016 to June 2017, 13 patients who underwent biportal endoscopic spinal surgery under the diagnosis of SEA were retrospectively enrolled in this study. The surgical indications of the enrolled patients included SEA with or without early stage spondylodiscitis who had neurological symptoms. Periopertaive data and clinical outcomes were assessed by regular serologic testing, imaging studies, physical examination, visual analog scale, Oswestry Disability Index and modified Macnab criteria.Offending pathogens were identified in seven (54%) of 13 biopsy specimens. Appropriate intravenous antibiotics for the identified pathogens isolated from infected tissue biopsy cultures were administrated to patients for at least 30 days. All patients reported satisfactory relief of pain and neurological symptoms after surgery. No surgery-related complications and recurrences were found after 2 years follow up.Biportal endoscopic spinal surgery may be an effective alternative to traditional open surgical decompression for the treatment of SEA.

Bone union after spinal fusion surgery using local bone in long-term bisphosphonate users: a prospective comparative study.

Bisphosphonates are the most commonly used drugs for osteoporosis and long-term use of bisphosphonates may affect fusion rate after spinal fusion surgery. There was significant delayed union after 6 months in long-term bisphosphonates users; however, there were no significant difference in fusion rate of long-term bisphosphonate users. Therefore, spinal fusion surgery should not be hesitated in long-term bisphosphonates users. PURPOSE: Bisphosphonates (BPs) are the most popular class of drugs for treatment of postmenopausal osteoporosis. Long-term use of BPs may also inhibit the spinal fusion process after posterior lumbar interbody fusion (PLIF). We compared bone fusion rates of long-term BPs users and non-users after undergoing spinal fusion surgery. METHODS: A total of 97 postmenopausal women who were candidates for single-level PLIF were recruited from 2015 to 2016. Participants were divided into two groups, with 63 patients in a long-term BPs user group and 34 patients in a non-user group. Serum C-terminal cross-linking telopeptide (CTX) levels were checked for bone resorption markers. Bone fusion rates were calculated at 6 months and 1 and 2 years after the surgery. Clinical outcomes were measured using the Oswestry Disability Index (ODI) and visual analog scale (VAS). RESULTS: Serum CTX level was dramatically decreased in the long-term BPs user group (p < 0.05). Fusion rates at 6 months after surgery were 42% in the non-user group and 26% in the long-term BPs user group (p = 0.035). However, fusion rates were 82% in the long-term BPs user group and 87% in the non-user group at 2 years after surgery (p > 0.05). There was no significant difference between the two groups in ODI or VAS. CONCLUSIONS: Even though there was significant delayed union after 6 months in long-term BPs users, at the 2-year postoperative follow-up, there was no significant difference in bone fusion rate between the two groups. Long-term BPs users showed fusion rates greater than 80% and clinical outcome improvements that were comparable to those in non-users. No significant effect on fusion rate after PLIF was found in long-term BPs users.