Risk Predictive Score and Cord Morphology Classification for Intraoperative Neuromonitoring Alerts in Kyphosis Surgery.

BACKGROUND: Intraoperative neuromonitoring (IONM) alert is one of the worrying events of kyphosis corrective surgery, which can result in a postoperative neurological deficit. To our knowledge, there is no risk prediction score to predict such events in patients undergoing kyphosis surgery. PURPOSE: To develop a new preoperative MRI-based cord morphology classification (CMC) and risk prediction score for predicting IONM alerts in patients with kyphotic deformity. STUDY DESIGN: Retrospective analysis of prospectively collected data PATIENT SAMPLE: 114 patients undergoing surgical correction for kyphotic deformity OUTCOME MEASURES: Intraoperative neuromonitoring alerts and postoperative neurological status using AIS grading. METHODS: Kyphotic deformity patients undergoing posterior spinal fusion were retrospectively reviewed. Based on the morphology of the spinal cord and surrounding CSF in MRI, there are five types of cord. Type 1 (normal cord): circular cord with surrounding visible CSF between the cord and the apex, Type 2 (flattened cord): cord with < 50% distortion at the apex with obliteration of the anterior CSF; Type 3 (deformed cord): cord with > 50% distortion at the apex with complete obliteration of the surrounding CSF; Type 4 (stretched cord): the cord is stretched and atrophied over the apex of the curve. Type 5 (translated cord): horizontal translation of the cord at the apex with buckling collapse of the vertebral column. Preoperative radiographs were used to measure the preoperative sagittal cobbs angle, sagittal deformity angular ratio (S-DAR), sagittal vertical axis (SVA), apex of the curve, and type of kyphosis. Clinical data like the duration of symptoms, clinical signs of myelopathy, neurological status (AIS grade), grade of myelopathy using the mJOA score, and type of osteotomy were documented. Multivariate logistic regression was used to determine the risk factors for IONM alerts and the risk prediction score was developed which was validated with new cohort of 30 patients. RESULTS: A total of 114 patients met the inclusion criteria. IONM alerts were documented in 33 patients (28.9%), with full recovery of the signal in 25 patients and a postoperative deficit in 8 patients. Rate of IONM alerts was significantly higher in Type 5 (66%), followed by Type 4 (50%), Type 3 (21.1%), Type 2 (11.1%), and Type 1 (11.1%) (p-value < 0.001). Based on multiple logistic regression, seven factors, namely preoperative neurological status, mJOA score ≤ 6, presence of signs of myelopathy, apex of the curve above T5, preoperative sagittal cobbs, S-DAR, and MRI-based CMC, were identified as risk predictors. The value for the risk factors varies from 0 to 4, and the maximum total risk score was 13. The cut-off value of 6 had good sensitivity (84.9%) and specificity (77.8%) indicating a high risk for IONM alerts. The AUC of the predictive model was 0.92, indicating excellent discriminative ability. CONCLUSION: We developed and validated a risk predictive score that identifies patients at risk of IONM alerts during kyphosis surgery. Identification of such high-risk patients (risk score ≥ 6) helps in proper evaluation and preoperative counselling and helps in providing a proper evidence-based reference for treatment strategies.

"Does the Gut microbiome influence disc health and disease?-the interplay between dysbiosis, pathobionts, and disc inflammation: a Pilot Study".

BACKGROUND CONTEXT: Gut microbiome alterations resulting in inflammatory responses have been implicated in many distant effects on different organs. However, its influence on disc health is still not fully investigated. PURPOSE: Our objective was to document the gut biome in healthy volunteers and patients with disc degeneration and to understand the role of gut dysbiosis on human disc health. STUDY DESIGN: Experimental case-control study. PATIENT SAMPLE: We included 40 patients with disc degeneration (DG) and 20 healthy volunteers (HV). HV comprised of age groups 30 to 60 years with no known record of back pain and no clinical comorbidities, with normal MRI. Diseased group (DG) were patients in the same age group undergoing surgery for disc disease (disc herniation-25; discogenic stenosis-15) and without instability (with Modic-20; and non-Modic-20). OUTCOME MEASURES: N/A. METHODS: We analyzed 16S V3-V4 rDNA gut metagenome from 20 healthy volunteers (HV) and compared the top signature genera from 40 patients with disc degeneration (DG) across Modic and non-Modic groups. Norgen Stool DNA Kit was used for DNA extraction from ∼200 mg of each faecal sample collected using the Norgen Stool Collection Kit.16S V3-V4 rDNA amplicons were generated with universal bacterial primers 341F and 806R and amplified with Q5 High-Fidelity DNA Polymerase. Libraries were sequenced with 250×2 PE to an average of 0.1 million raw reads per sample (Illumina Novaseq 6000). Demultiplexed raw data was assessed with FastQC, and adapter trimmed reads >Q30 reads were processed in the QIME2 pipeline. Serum C-reactive protein (CRP) was measured by the immunoturbimetry method and Fatty acid-binding protein 5 (FABP5) was measured in albumin-globulin-depleted plasma through global proteome analysis. RESULTS: We observed significant gut dysbiosis between HV and DG and also between the Modic and non-Modic groups. In the Modic group, commensals Bifidobacterium and Ruminococcus were significantly depleted, while pathobionts Streptococcus, Prevotella, and Butryvibrio were enriched. Firmicutes/Bacteroidetes ratio was decreased in DG (Modic-0.62, non-Modic-0.43) compared to HV (0.70). Bacteria-producing beneficial short-chain fatty acids were also depleted in DG. Elevated serum CRP and increased FABP5 were observed in DG. CONCLUSION: The study revealed gut dysbiosis, an altered Firmicutes/Bacteroidetes ratio, reduced SCFA-producing bacteria, and increased systemic and local inflammation in association with disc disease, especially in Modic changes. The findings have considerable importance for our understanding and prevention of disc degeneration.

Foot pressure transfers are altered in lumbar radiculopathy but reversible after surgery: a prospective, Pedobarography study.

BACKGROUND CONTEXT: Patients with lower lumbar stenosis and disc herniation report disability in standing and ambulation, despite normal neurological examination. The L5 and S1 nerve roots support the entire motor and sensory function of the foot, and their radiculopathy can affect foot loading during standing and walking. This has not been quantified before. PURPOSE: To quantify alterations in static and dynamic foot pressure transfers in patients with lower lumbar nerve root compression, and document any beneficial effects of surgical decompression. STUDY DESIGN: Prospective, case-control study. PATIENT SAMPLE: Cases-Patients with unilateral radiculopathy (L5/S1) with normal neurology (n=50); Controls - Healthy volunteers (n=50). METHODS: The volunteers and patients underwent pedobarographic analysis during standing (static) and walking (dynamic), and fifteen (12 dynamic and three static) parameters were documented. The patient's preoperative values were compared with that of the healthy volunteers. All the 50 patients underwent surgical decompression, and clinical outcome measures (VAS/ODI at 3 months) were documented. Pedobarographic analysis was repeated in the postoperative period (48 hours) and 3-month follow-up and compared with the preoperative scores. RESULTS: In healthy controls, the mean values of all 15 parameters were comparable between the right and the left side (p>.05). When compared to controls, the patients had significantly lower maximum foot loads (p=.01) and average foot loads (p=.05) on the affected side during walking indicating lesser load transmission, in the preoperative period. Within the affected foot, the load transfer was higher on the first metatarsal/ medial arch while significantly less on the lateral metatarsals (p=.04). The percentage load on whole foot and forefoot was significantly less on standing (p=.01). Significant improvements were noted in the post-operative period, especially in the maximum foot surface area (p=.01), maximum and average foot loads, and improved weight transfers on lateral arch and forefoot (p=.02). The load on whole foot increased significantly from 46.1%±5.5% (preoperative) to 48.1%±5.5% (postoperative) and 49.9%±3.3% at follow-up (p=.01). CONCLUSION: This is the first study using Pedobarography to document altered foot pressure patterns during ambulation in patients with disc herniation and stenosis. Decreased load transfer, asymmetrical and unphysiological distribution of pressures on the affected foot were observed during weight bearing, which improved after surgical decompression.

Efficacy and Safety of Ultrasound Guided Inter-semispinal Plane Block for Postoperative Analgesia in Posterior Cervical Laminectomy - A Prospective Randomised Controlled Study.

STUDY DESIGN: Prospective, randomized controlled study. OBJECTIVE: To assess the safety and efficacy of an ultrasound-guided ISP block for postoperative analgesia in posterior cervical laminectomy. METHODS: 88 patients requiring posterior cervical laminectomy were randomized into two groups, those who underwent ISP block with multimodal analgesia (ISPB group) and those with only multimodal analgesia (control group). Demographic details, intraoperative parameters (blood loss, duration of surgery, perioperative total opioid consumption, muscle relaxants used), and postoperative parameters (numeric rating scale, satisfaction score, mobilization time, and complications) were recorded. RESULTS: The total opioid consumption (128.41 + 39.65vs 284.09 + 140.92mcg; P < .001), muscle relaxant usage (46.14 + 6.18 mg vs 59.32 + 3.97 mg; P < .001), surgical duration (128.61 + 26.08/160.23 + 30.99mins; P < .01), and intra-operative blood loss (233.18 + 66.08 mL vs 409.77 + 115.41 mL; P < .01) were significantly less in the ISPB group compared to the control. In the postoperative period, the control group's pain score was significantly higher (P < .001) in the initial 48 hours. The Modified Observer Alertness/Sedation Score (MOASS) score and satisfaction scores were significantly better in the ISPB compared to the control (P < .001). The mean time required to ambulate was statistically less in ISPB (4.30 + 1.64hours) when compared to controls (9.48 + 3.07hours) (P < .001). CONCLUSION: In patients undergoing posterior cervical laminectomy, ISP block is a safe and effective technique with better outcomes than standard multi-modal analgesia alone, in terms of reduced intra-operative opioid requirements and blood loss, better postoperative analgesia, and early mobilization.

Does Magnetic Resonance Imaging Predict Neurological Deficit in Patients with Traumatic Lower Lumbar Fractures?

STUDY DESIGN: A retrospective cohort study. PURPOSE: This study aimed to understand the role of magnetic resonance imaging (MRI) in predicting neurological deficits in traumatic lower lumbar fractures (LLFs; L3-L5). OVERVIEW OF LITERATURE: Despite studies on the radiological risk factors for neurological deficits in thoracolumbar fractures, very few have focused on LLFs. Moreover, the potential utility of MRI in LLFs has not been evaluated. METHODS: In total, 108 patients who underwent surgery for traumatic LLFs between January 2010 and January 2020 were reviewed to obtain their demographic details, injury level, and neurology status at the time of presentation (American Spinal Injury Association [ASIA] grade). Preoperative computed tomography scans were used to measure parameters such as anterior vertebral body height, posterior vertebral body height, loss of vertebral body height, local kyphosis, retropulsion of fracture fragment, interpedicular distance, canal compromise, sagittal transverse ratio, and presence of vertical lamina fracture. MRI was used to measure the canal encroachment ratio (CER), cross-sectional area of the thecal sac (CSAT), and presence of an epidural hematoma. RESULTS: Of the 108 patients, 9 (8.3%) had ASIA A, 4 (3.7%) had ASIA B, 17 (15.7%) had ASIA C, 21 (19.4%) had ASIA D, and 57 (52.9%) had ASIA E neurology upon admission. The Thoracolumbar Injury Classification and Severity score (p =0.000), CER (p =0.050), and CSAT (p =0.019) were found to be independently associated with neurological deficits on the multivariate analysis. The receiver operating characteristic curves showed that only CER (area under the curve [AUC], 0.926; 95% confidence interval [CI], 0.860-0.968) and CSAT (AUC, 0.963; 95% CI, 0.908-0.990) had good discriminatory ability, with the optimal cutoff of 50% and 65.3 mm2, respectively. CONCLUSIONS: Based on the results, the optimal cutoff values of CER >50% and CSAT >65.3 mm2 can predict the incidence of neurological deficits in LLFs.

Functional and Radiological Outcomes of All-Posterior Surgical Correction of Dystrophic Curves in Patients with Neurofibromatosis Type 1.

STUDY DESIGN: A retrospective cohort study. PURPOSE: To determine outcomes following all-posterior surgery using computed tomography navigation, hybrid stabilization, and multiple anchor point techniques in patients with neurofibromatosis type 1 (NF-1) and dystrophic scoliosis. OVERVIEW OF LITERATURE: Previous studies favored antero-posterior fusion as the most reliable method; however, approaching the spine anteriorly was fraught with significant complications. With the advent of computer assisted navigation and multiple anchor point method, posterior only approach is reporting successful outcomes. METHODS: This study included patients who underwent all-posterior surgical deformity correction for dystrophic NF-1 curves. Coronal and sagittal Cobbs angles, apical rotation, and the presence of dystrophic features were evaluated before surgery. Postoperatively, sagittal, coronal, and axial correction, implant position, and implant densities were evaluated. The decline in curve correction and implant-related complications were evaluated at follow-up. Clinical outcomes were evaluated using the Scoliosis Research Society-22 revised index. RESULTS: This study involved 50 patients with a mean age of 13.6 years and a mean follow-up duration of 5.52 years. With a mean coronal flexibility of 18.7%, the mean apical vertebral rotation (AVR), preoperative coronal Cobb angle, and sagittal kyphosis were 27.4°, 64.01°, and 47.70°, respectively. The postoperative mean coronal Cobb angle was 30.17° (p <0.05), and the sagittal kyphosis angle was 25.4° (p <0.05). The average AVR correction rate was 41.3%. The correction remained significant at the final mean follow-up, with a coronal Cobb angle of 34.14° and sagittal kyphosis of 25.02° (p <0.05). The average implant density was 1.41, with 46% of patients having a high implant density (HID). The HID had a markedly higher mean curve correction (29.30° vs. 38.05°, p <0.05) and a lower mean loss of correction (5.7° vs. 3.8°, p <0.05). CONCLUSIONS: Utilizing computer-assisted navigation, hybrid instrumentation, and multiple anchor point technique and attaining high implant densities, this study demonstrates successful outcomes following posterior-only surgical correction of dystrophic scoliosis in patients with NF-1.

The disc-endplate-bone-marrow complex classification: progress in our understanding of Modic vertebral endplate changes and their clinical relevance.

BACKGROUND CONTEXT: The disc, endplate (EP), and bone marrow region of the spine form a single anatomical and functional interdependent unit; isolated degeneration of any one structure is rare. Modic changes (MC), however, are restricted to the subchondral bone alone and based on only T1 and T2 sequences of MRI. This results in poor reliability in differentiating fat from edema and hence may give a false impression of disease inactivity. PURPOSE: To study the changes in disc, endplate, and bone marrow as a whole in degeneration and propose a classification based on the activity status of this complex with the addition of STIR MRI sequences. STUDY DESIGN: Observational cohort. PATIENT SAMPLE: Patients with isolated brain, cervical, or thoracic spine injury and patients with low back pain (LBP) who underwent MRI formed the control and study groups, respectively. OUTCOME MEASURES: Demographic data, the prevalence of MC and disc-endplate-bone marrow classification (DEBC) changes, EPs undergoing reclassification based on DEBC, and comparison of the prevalence of MC, DEBC, H+modifier and DEBC with H+concordance between control and LBP group. The study determined the risk of LBP patients undergoing surgery as well as the incidence of postoperative infection based on DEBC changes. Significance was calculated by binomial test and chi-square test with the effect size of 0.3 to 0.5. Prevalence and association of outcome were calculated by Altman's odds ratio with the 95% CI and the scoring of z statistics. Logistic expression was plotted for independent variables associated with each class of both Modic and DEBC against dependent variables surgery and nonsurgery. METHODS: Lumbar segments in both groups were assessed for MC types. The DEBC classification was developed with the addition of STIR images and studying the interdependent complex as a whole: type-A: acute inflammation; type-B: chronic persistence; type-C: latent and type-D: inactive. Modifier H+ was added if there was disc herniation. The classification was compared with MC and correlated to clinical outcomes. RESULTS: A total of 3,560 EPs of 445 controls and 8,680 EPs in 1,085 patients with LBP were assessed. Four nonMC, 560 MC-II, and 22 MC-III EPs were found to have previously undetected edema in STIR (n=542) or hyperintensity in discs (n=44) needing reclassification. The formerly undescribed type-B of DEBC, representing a chronic persistent activity state was the most common (51.8%) type. The difference between the control and LBP of H+(12% vs 28.8%) and its co-occurrence with DEBC type 1.1% vs 23.3%) was significant (p<.0001). The odds ratio for the need for surgery was highest (OR=5.2) when H+ and DEBC type change co-occurred. Postoperative deep infection (as determined by CDC criteria) was 0.47% in nonDEBC, compared with 2.4% in patients with DEBC (p=.002), with maximum occurrence in type-B. CONCLUSION: Classification based on the classic MC was found to need a reclassification in 586 EPs showing the shortcomings of results of previous studies. Considering the DEBC allowed better classification and better predictability for the need for surgical intervention and incidence of postoperative infection rate than MC.

Active tuberculosis of spine: Current updates.

Background: Spinal tuberculosis (TB) is the most common extrapulmonary form of tuberculosis. In both developing and developed countries, TB has been on the rising trend due to factors such as increasing HIV coinfection, multidrug resistance of the organism, and global migration. Spinal TB, which most often affects the lower thoracic and thoracolumbar area, accounts for 50% of all musculoskeletal tuberculosis. Methods: Using the Cochrane Database of Systematic Reviews, EMBASE, and PubMed, a systematic computerized literature search was performed. Analyses of studies published within the past 10 years were conducted. The searches were performed using Medical Subject Headings terms, with "spinal tuberculosis," "diagnosis," "epidemiology," and "etiology","management," "surgery," and "therapy" as subheadings. Results: Progressive collapse, kyphosis, and neurological deficiency are hallmarks of the disease because of its destructive effect on the intervertebral disc and adjacent vertebral bodies. The condition may be identified using laboratory testing and distinctive imaging features, but the gold standard for diagnosis is tissue diagnosis using cultures, histology, and polymerase chain reaction. Uncomplicated spinal TB is today a medical condition that can be adequately treated by multidrug ambulatory chemotherapy. Surgery is reserved for individuals who have instability, neurological impairment, and deformity correction. Debridement, deformity correction, and stable fusion are the cornerstones of surgical treatment. Conclusions: Clinical results for the treatment of spinal TB are generally satisfactory when the disease is identified and treated early. However, the major health issue and the biggest obstacle in achieving the goals of the "End TB strategy" is the recent rise in the emergence of drug resistance. Hence strict vigilance and patient perseverance in the completion of the treatment is the main need of the hour.

Comparison Between Relative Efficacy of Erector Spinae Plane Block and Caudal Epidural Block for Postoperative Analgesia in Lumbar Fusion Surgery- A Prospective Randomized Controlled Study.

STUDY DESIGN: Prospective, randomized controlled double-blinded study. OBJECTIVE: To compare the relative efficacy of ultrasound-guided ESPB and CEB for postoperative analgesia after a single-level lumbar fusion surgery and compared it with conventional multimodal analgesia. METHODS: 81 patients requiring single-level lumbar fusion surgery were randomly allocated into 3 groups (ESPB group, CEB group, and the control group). Demographic and surgical data (blood loss, duration of surgery, perioperative total opioid consumption, muscle relaxants used) were assessed. Postoperatively, the surgical site pain, alertness scale, satisfaction score, time to mobilization, and complications were recorded. RESULTS: The total opioid consumption in the first 24 hours was significantly lower in both the block groups than in the control group (103.70 ± 13.34 vs 105 ± 16.01 vs 142.59 ± 40.91mcg; P < .001). The total muscle relaxant consumption was also significantly less in block groups compared to controls (50.93 ± 1.98 vs 52.04 ± 3.47 vs 55.00 ± 5.29 mg; P < .001). The intraoperative blood loss was significantly less in both the block group (327.78 ± 40.03 mL, 380.74 ± 77.80 mL) than the control group (498.89 ± 71.22 mL) (P < .001). Among the block groups, the immediate postoperative pain relief was better in the CEB group, however, the ESPB group had a longer duration of postoperative pain relief. CONCLUSION: Both ESPB and CEB produce adequate postoperative analgesia after lumbar fusion however the duration of action was significantly longer in the ESPB group with relatively shorter surgical time and lesser blood loss compared to the CEB group.

Current trends and advancements in spine surgery.

In recent years, spine surgery has undergone remarkable advancements, revolutionized the field, and transformed patient care. This special issue of the Journal of Orthopedics provides the best possible knowledge for its readers about the current trends and recent innovations in the field of spine surgery and supports clinicians and surgeons in their daily practice and decision-making process. It covers various topics like artificial intelligence in spine surgery, 3D printing, minimally invasive spine surgery. It also provides needed information on modic changes, management of eary onset scoliosis and recent trends in spinal cord injury management.

Giant Anomalous Cervical Spinous Process Causing Dynamic Cord Compression: An Unusual Cause for Myelopathy: A Case Report.

CASE: A 47-year-old male patient presented with progressively worsening gait instability caused by a giant anomalous, free-floating C5 spinous process resulting in dynamic cord compression and myelopathy. The patient was successfully managed with a C5 laminectomy and total excision of the anomalous spinous process with a good functional outcome at the final follow-up. CONCLUSION: Anomalies of the posterior arch of the subaxial cervical spine are relatively uncommon and asymptomatic. This case is being reported for its rarity and to highlight the role of dynamic imaging in patients presenting with congenital anomalies of the cervical spine presenting with compressive myelopathy.

Vancomycin Flushing Syndrome After the Use of Vancomycin-Impregnated Bone Graft During Spine Surgery: A Case Report.

CASE: Intrawound vancomycin in spine surgery is a common clinical practice. We report a case of a 14-year-old adolescent girl undergoing surgery for scoliosis correction who developed features of vancomycin flushing syndrome after the use of vancomycin-impregnated bone graft. After resuscitation, she was extubated and had an uneventful postoperative recovery. At 1-year follow-up, she is back to her routine without any sequelae of the intraoperative event. CONCLUSION: The use of intrawound vancomycin can result in life-threatening reactions. With the increase in its use, the anesthetist and the surgeon must be aware of such complications.

Ralstonia mannitolilytica as a rare cause of spondylodiscitis following endoscopic lumbar discectomy- A report of two cases.

Ralstonia mannitolilytica is a low-virulence, gram-negative bacillus which causes opportunistic infections in immunosuppressed patients. Postoperative spondylodiscitis by R. mannitolilytica has not been reported so far. We report the management of two cases of postoperative spondylodiscitis caused by Ralstonia mannitolilytica presenting to our center within a span of one month following endoscopic lumbar discectomy at a different center. They were managed successfully by surgical debridement and appropriate antibiotics. In these two cases of R.mannitolilytica spondylodiscitis, prompt detection, and intensive treatment resulted in satisfactory outcomes in terms of fulfilling the purpose of the original surgery.

Propensity matched outcome analysis following microdiscectomy versus interlaminar endoscopic discectomy for L5-S1 disc herniation.

Purpose: The main purpose of the study is to perform a propensity-matched functional outcome analysis following microdiscectomy (MD) versus interlaminar endoscopic lumbar discectomy (IELD) for L5-S1 disc herniation. Although many studies have compared endoscopic lumbar discectomy and microdiscectomy, few have compared the outcomes of microdiscectomy (MD) and interlaminar endoscopic discectomy (IELD) at the L5-S1 level. Methods: This is a propensity-matched analysis of 100 patients (50 MD patients, 50 IELD patients) based on baseline covariates with a minimum of one-year follow-up. Patient-reported outcome measures were obtained from EMR during follow-up visits. Back pain and sciatic pain were assessed by the Visual Analogue Scale (VAS-B and VAS-L). Functional outcome was assessed using Oswestry Disability Index (ODI) Score and 12-item Short Form Survey (SF-12) score. Data were obtained at baseline (pre-op) and at 0, 1, 3, and 12 months post-operatively. Results: Mean operative time was significantly lower (p < 0.001) in the IELD group (44 min) compared to the MD group (59 min). Mean VAS-B at the immediate and 1-month postoperative period was significantly (p < 0.001) lower in the IELD group (0.36, 0.24) when compared with the MD group (1.74, 1.16). There was no significant difference between IELD and MD groups with regard to improvement in sciatic pain (VAS-L). ODI scores at 1 month and 3 months post-operative period were significantly (p < 0.001) lower in the IELD group (30.1, 23.2) when compared with the MD group (41, 27.5). However, there was no significant difference between the two groups with regards to VAS-B, ODI, and SF-12 at 1-year follow-up. Conclusion: Our findings indicate that the IELD group achieved better immediate and early postoperative outcomes despite no significant difference at one-year follow-up.

Dural injury following elective spine surgery - A prospective analysis of risk factors, management and complications.

Incidental dural tears being a familiar complication in spine surgery could result in dreaded postoperative outcomes. Though the literature pertaining to their incidence and management is vast, it is limited by the retrospective study designs and smaller case series. Hence, we performed a prospective study in our institute to determine the incidence, surgical risk factors, complications and surgical outcomes in patients with unintended durotomy during spine surgery over a period of one year. The overall incidence in our study was 2.3% (44/1912). Revision spine surgeries in particular had a higher incidence of 16.6%. The average age of the study population was 51.6 years. The most common intraoperative surgical step associated with dural tear was removal of the lamina, and 50% of the injuries were during usage of kerrison rongeur. The most common location of the tear was paramedian location (20 patients) and the most common size of the tear was about 1 mm-5mm (31 patients). We observed that the dural repair techniques, placement of drain and prolonged post-operative bed rest didnot significantly affect the post-operative outcomes. One patient in our study developed persistent CSF leak, which was treated by subarachnoid lumbar drain placement. No patients developed pseudomeningocele or post-operative neurological worsening or re-exploration for dural repair. Wound complications were noted in 4 patients and treated by debridement and antibiotics. Based on our study, we have proposed a treatment algorithm for the management of dural tears in spine surgery.

"Are we barking up the wrong tree? Too much emphasis on Cutibacterium acnes and ignoring other pathogens"- a study based on next-generation sequencing of normal and diseased discs.

BACKGROUND: The majority of literature on bacterial flora in the disc stands disadvantaged in utilizing traditional culture methods and targeting a single bacterium, Cutibacterium acnes. PURPOSE: Our objective was to document the diversity in the bacterial flora between normal and degenerated discs for shortlisting potential pathogens using next-generation genomic tools. STUDY DESIGN: Experimental case-control study. METHODS: Researchers employed 16S metagenome sequencing to profile bacterial diversity in magnetic resonance imaging normal healthy discs from brain-dead organ voluntary donors (n=20) and 40 degenerated disc samples harvested during surgery (Modic [MC]=20 and non-Modic [NMC]=20). The V3-V4 region was amplified using universal bacterial primers 341F and 806R, and the libraries were sequenced using Illumina NovoSeq 6000 platform. Statistical significance was set at bacteria with a minimum of 100 operational taxonomic unit (OTU) and present in at least 70% of the samples. The quality check-filtered reads were processed using the QIIME-2 pipeline. The OTU clustering and taxonomic classification were carried out for the merged reads using the Greengenes/SILVA reference database. Validation was done by identification of bacterial metabolites in samples using the liquid chromatography-mass spectrometry approach. RESULTS: Abundant bacteria differing widely in diversity, as evidenced by Alfa and Beta diversity analysis, were present in all control and degenerative samples. The number of bacterial genera was 27 (14-gram-positive: 13-gram-negative) in the control group, 23 (10-gram-positive: 11-gram-negative) in the Modic group, and 16 (11-gram-positive: 5-gram-negative) in the non-Modic group. In the Modic group, gram-negative bacteria OTUs were found to be predominant (more than 50% of the total bacteria identified), whereas in control and non-Modic groups the OTUs of gram-positive bacteria were predominant. Species-level analysis revealed an abundance of opportunistic gram-negative pathogens like Pseudomonas aeruginosa, Sphingomonos paucibacillus, and Ochrobactrum quorumnocens in the discs with Modic changes, more than in non-Modic discs. The presence of bacterial metabolites and quorum-sensing molecules like N-decanoyl-L-homoserine lactone, 6-hydroxynicotinic acid, 2-aminoacetophenone, 4-hydroxy-3-polyprenylbenzoate, PE (16:1(9Z)/18:0) and phthalic acid validated the colonization and cell-cell communication of bacteria in disc ruling out contamination theory. Cutibacterium acnes was not the predominant bacteria in any of the three groups of discs and in fact was in the 16th position in the order of abundance in the control discs (0.72%), seventh position in the Modic discs (1.41%), and 12th position (0.53%) in the non-Modic discs. CONCLUSION: This study identified a predominance of gram-negative bacteria in degenerated discs and highlights that Cutibacterium acnes may not be the only degeneration-causing bacteria. This may be attributed to the environment, diet, and lifestyle habits of the sample population. Though the study does not reveal the exact pathogen, it may pave the way for future studies on the subject. CLINICAL SIGNIFICANCE: These findings invite further investigation into causal relationships of bacterial profile with disc degeneration phenotypes as well as phenotype-driven clinical treatment protocols.

Analysis of Postoperative Clinical Outcomes in Cervical Myelopathy due to Ossification of Posterior Longitudinal Ligament Involving C2.

STUDY DESIGN: Retrospective study. PURPOSE: To investigate the radiological phenotype, patient and surgery-related risk factors influencing postoperative clinical outcome for cervical myelopathy caused by ossification of the posterior longitudinal ligament involving C2 following posterior instrumented laminectomy and fusion. OVERVIEW OF LITERATURE: Ossified posterior longitudinal ligament (OPLL) is caused by ectopic ossification of the posterior longitudinal ligament. It can cause neurological impairment and severe disability. For multilevel cervical OPLL, studies have shown good neurological recovery following cord decompression via either an anterior or posterior approach. There is, however, a lacunae in the literature regarding the outcomes of patients with OPLL extending to C2 and above (C2 [+]). METHODS: We retrospectively studied 61 patients with C2 (+) OPLL who had posterior instrumented laminectomy and fusion at Ganga Hospital, Coimbatore between July 2011 and January 2021, with a minimum follow-up of 2 years. Data on demographics, clinical outcomes, radiology, and post-surgical outcomes were gathered. RESULTS: Among 61 patients, 56 were males and five were females. The OPLL pattern was mixed in 32 cases (52.5%), continuous in 26 cases (42.6%), segmental in two cases (3.3%), and circumscribed in one patient (1.6%). All of our patients showed signs of neurological improvement after a 24-month follow-up. The mean preoperative modified Japanese Orthopaedic Association (mJOA) score was 10.6 (range, 5-11) and the postoperative mJOA score was 15.8 (range, 12-18). The recovery rate was >75% in 27 patients (44.6%), >50% in 32 patients (52.5%), and >25% in two patients (3.3%). The average recovery rate was 71% (range, 33%-100%). The independent risk factor for predicting recovery rate is the preoperative mJOA score. CONCLUSIONS: In C2 (+) OPLL, posterior instrumented decompression and fusion provide a relatively safe approach and satisfactory results.

Ultrasonic bone scalpel in spine surgery.

Background: Spine surgery has always been considered technically demanding even in the hands of the most experienced surgeon on account of close proximity of vital soft tissue structures. Technical advancements over the last few decades have been crucial for the progress of this complex speciality which not only increased the surgical accuracy, but patient safety as well. Ultrasonic devices are one such innovation based on piezoelectric vibrations, patented by Fernando Bianchetti, Domenico Vercellotti, and Tomaso Vercellotti in 1988. Methods: We did an extensive literature search on ultrasonic devices and their applications in the field of spine surgery. Results: We present the various ultrasonic bone devices available including their physical, technologic and clinical aspects in spine surgery. We also attempt to cover the limitations and future advances of Ultrasonic bone scalpel (UBS) in particular, which would be interesting and informative for any spine surgeon who is novice in this field. Conclusion: UBS has been found to be safe and effective in all forms of spine surgeries offering distinct advantages over conventional instruments, although limited by an inherent learning curve.

Surgical Approach to Cervical Fractures in Ankylosing Spondylitis Patients: Rationale and Surgical Strategy.

BACKGROUND: Current literature lacks objective criteria to determine surgical management in patients with ankylosing spondylitis who sustain cervical fractures. The purpose of our study was to analyze the determinants for stratifying surgical approach, evaluate the outcome in patients, and postulate a management strategy. METHODS: This was a retrospective study of patients with ankylosing spondylitis who underwent surgery for cervical spine injury with a minimum follow-up of 2 years. Neurological recovery, fracture pattern including translation and angulation, surgical duration, blood loss, and postoperative complications were recorded, and a comparative analysis of these factors with anterior, posterior, and combined surgical approaches was performed. RESULTS: The study included 43 men with a mean age of 57 years; 49% underwent anterior-only stabilization, 16% underwent posterior-only stabilization, and 35% underwent combined anteroposterior stabilization. Mean operative time was significantly lower in anterior-only (81.4 minutes; P < 0.05) and posterior-only (124 minutes; P < 0.05) approaches compared with combined approach (266.6 minutes). Mean blood loss was significantly lower in anterior-only (87.5 mL, P < 0.05) approach compared with posterior-only (714.7 mL) and combined (912.7 mL) approaches. Mean translation was 1.8 mm, 1.7 mm, and 3.7 mm in anterior, posterior, and combined approaches (P < 0.05), respectively. CONCLUSIONS: Our study provides insights into management of cervical spine fractures in ankylosing spondylitis patients. A fracture displacement ≤2 mm may be successfully managed by an anterior approach, while the posterior approach may be beneficial in similar fractures warranting instrumentation extending to the thoracic spine. All other fractures warrant a combined surgical approach.