Safety and efficacy of intrawound vancomycin powder in the prevention of lumbar surgical site infection: A prospective, double-blind, randomized controlled study.

BACKGROUND: To evaluate the safety and efficacy of intra-wound vancomycin powder in reducing surgical site infections (SSIs) after spine surgery. DESIGN: A prospective, double-blind, randomized controlled study. PARTICIPANTS: Patients who underwent posterior lumbar interbody fusion (PLIF) surgery from May 2021 to September 2022. METHODS: Patients who underwent posterior lumbar interbody fusion (PLIF) surgery between May 2021 and September 2022 were included. Participants were randomized to the vancomycin treatment or control groups using block randomization (block size 4). Except for baseline and surgical data, the plasma levels of white blood cells, C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), aspartate aminotransferase, alanine aminotransferase, and serum vancomycin concentration in the groups were analyzed on postoperative days (PODs) 1, 3, and 5. Vancomycin concentration was measured daily until the drainage tubes were removed. The primary outcomes were the 90-day vancomycin-related adverse reactions and SSI rates. Secondary outcomes were perioperative hematological parameters and vancomycin serum (drain) concentrations. RESULTS: A total of 156 participants (78 each in each group) were analyzed by an independent researcher. The follow-up rate was 91%. All participants were followed up for at least 90 days. The 90-day SSI rate in the vancomycin group was 1.3% (1/78), comprising one case of superficial infection. The SSI rate in the control group was 10.3% (8/78), comprising seven cases of superficial infection and one case of deep infection. Compared with that in the control group, the SSI rate in the vancomycin group was decreased by 87.5%, with a statistically significant difference (RR=0.125, 95% CI=0.016-0.976). Additionally, the vancomycin group demonstrated a statistically significant decrease in serum ESR on POD 3 (P=0.039) and CRP on POD 5 (P=0.024) compared to the control group. The local plasma concentration of vancomycin remained elevated for at least 4 days postoperatively, while the serum concentration of vancomycin remined low. Vancomycin-associated adverse reactions were not observed. CONCLUSION: Intra-wound application of vancomycin powder is a safe and effective procedure for reducing the risk of SSI during PLIF surgery.

Percutaneous endoscopic transforaminal discectomy and unilateral biportal endoscopic discectomy for lumbar disc herniation: a comparative analysis of learning curves.

OBJECTIVE: The purpose of this study was to investigate the learning curve of percutaneous endoscopic transforaminal discectomy (PETD) and interlaminar unilateral biportal endoscopic discectomy (UBED) in the treatment of lumbar disc herniation (LDH). METHODS: Between 2018 and 2023, 120 consecutive patients with lumbar disc herniation (LDH) treated by endoscopic lumbar discectomy were retrospectively included. The PETD group comprised 87 cases, and the UBED group comprised 33 cases. Cumulative sum analysis was used to evaluate the learning curve, with the occurrence of complications or unresolved symptoms defined as surgical failure, and variables of different phases of the learning curve being compared. RESULTS: The learning curve analysis identified the cutoff point at 40 cases in the PETD group and 15 cases in the UBED group. In the mastery phase, both PETD and UBED demonstrated a significant reduction in operation times (approximately 38 min for PTED and 49 min for UBED). In both PETD and UBED groups, the surgical failure rates during the learning and mastery phases showed no statistically significant differences. The visual analogue scale at the last follow-up was significantly lower than before surgery in both the PETD and UBED groups. CONCLUSION: PETD and UBED surgery are effective in the treatment of LDH with a low incidence of complications. However, achieving mastery in PETD necessitates a learning curve of 40 cases, while UBED requires a minimum of 15 cases to reach proficiency.

Greater pelvic obliquity in adolescent idiopathic scoliosis combined with hip dysplasia.

BACKGROUND: Adolescent idiopathic scoliosis (AIS) is a spinal deformity that affects adolescents and poses a challenging public health problem. Compared to the general population, adolescents with AIS have a higher prevalence of hip dysplasia. However, the mechanisms underlying the impact of hip dysplasia on the coronal balance of the spine remain poorly understood. We hypothesized that the combination of AIS with hip dysplasia would exacerbate coronal imbalance. METHODS: We retrospectively analyzed the medical records and radiographs of adolescents diagnosed with AIS between 2015 and 2020. Participants were divided into two groups: those with hip dysplasia and those without. We recorded parameters related to the coronal deformity of the spine, sacral and pelvic obliquity, and center edge angle (CEA). We investigated differences in these parameters in those with and without hip dysplasia and analyzed their relationships in those with combined AIS and hip dysplasia. RESULTS: A total of 103 adolescents were included, 36 with hip dysplasia and 67 without. Those with hip dysplasia had significantly higher sacroiliac discrepancy (SID) compared to those without (t = - 2.438, P = 0.017). In adolescents with hip dysplasia, only iliac obliquity angle (IOA) was significantly correlated with SID (r = - 0.803, P < 0.001), with a linear relationship between them (r2 = 0.645, P < 0.001). CONCLUSIONS: The incidence of hip dysplasia is higher in the AIS population. In adolescents with combined AIS and hip dysplasia, pelvic obliquity is greater, potentially contributing to the increased prevalence of low back pain.

Low profile posterior lumbar-sacral interbody fusion for lumbosacral degenerative diseases: a technical note.

BACKGROUND: The purpose of this study was to report our surgical experience in patients with lumbosacral degenerative diseases who underwent posterior decompression and interbody fusion fixed with cortical bone trajectory screw and sacral alar screw, which is known as low-profile posterior lumbosacral interbody fusion (LP-PLSIF). METHODS: Patients with lumbosacral degenerative disease who underwent LP-PLSIF and traditional PLSIF (control group) internally fixed with pedicle screws were included retrospectively. Patients' demographic data, operative parameters, and perioperative complications were recorded and analyzed. RESULTS: A total of 18 patients were enrolled in this study, which included 9 patients (5 male and 4 female) who underwent LP-PLSIF, and 9 patients (4 male and 5 female) who underwent traditional PLSIF. There wasn't a significant difference in the average age between the two groups, 56.78 ± 10.92 years in the LP-PLSIF group and 60.22 ± 8.21 years in the PLSIF group (p = 0.460). The bone mineral density (BMD) of the two groups of patients were -2.00 ± 0.26 T and -2.13 ± 0.19 T, respectively (P = 0.239). The mean postoperative follow-up time was 12.7 months (range, 12-14 months). The mean operation time was 142.78 ± 11.21 min and 156.11 ± 13.41 min in the LP-PLSIF group and PLSIF group respectively (P < 0.05). The average blood loss was 137.78 ± 37.09 ml in the LP-PLSIF group, and 150.00 ± 27.84 ml in the PLSIF group (P = 0.441). The average postoperative drainage was 85.56 ± 37.45 ml and 122.22 ± 22.24 ml in the LP-PLSIF group and control group respectively (P < 0.05). Patients in the LP-PLSIF group had shorter incision length compared with the control group, 61.44 ± 10.56 mm vs. 74.56 ± 10.22 mm (P < 0.05). The average length of hospitalization of 11.33 ± 2.92 days in the LP-PLSIF group, and 11.11 ± 1.62 days in the PLSIF group (p = 0.844). All patients had significant improvement in VAS pain score, ODI, and JOA evaluation. However, patients in the LP-PLSIF group had better improvement in terms of VAS back pain and ODI in the short term after the operation. There were no neurological complications or wound infection. The fusion rate at the last follow-up was 100% (9 of 9) in the LP-PLSIF group, and 88.89% (8 of 9) in the control group based on CT scans. 1 patient in the control group had asymptomatic sacral pedicle screw loosening. CONCLUSIONS: LP-PLSIF is a safe and effective surgical technique for patients with lumbosacral degenerative disease, which has the potential strength of less invasive and better clinical improvement.

The accuracy of cortical bone trajectory screw placement guided by spinous process clamp hardware in lumbar spinal surgery: a retrospective study.

This study aimed to assess the accuracy of cortical bone trajectory (CBT) screws placement guided by a spinous process clamp (SPC) guide. A total of 32 patients who received single-level midline lumbar fusion (MIDLF) surgery between June 2019 and January 2020 were retrospectively analyzed and divided into free-hand (FH) and SPC-guided groups according to the surgical approach. In the FH group, CBT screws was implanted with the assistance of fluoroscopy, while in the SPC group, CBT screws was implanted using the SPC navigator hardwire. A total of 128 screws were assessed in this study, with higher rates of clinically acceptable screw placement (grades A and B) and grade A screws in the SPC group than in the FH guide group (92.2% vs. 79.7%, P = 0.042 and 54.7% vs. 35.9%, P = 0.033, respectively). Misplacement screws (grades C, D, and E) occurred more often in the FH group than in the SPC guide group (20.3% vs. 7.8%, P = 0.042). The incidence of proximal facet joint violation (FJV) was higher in the FH group than in the SPC group (15.6% vs. 3.1%, P = 0.030). The radiation dose and time in the SPC guide group were comparable to those in the FH group (P = 0.063 and P = 0.078). The average operative time was significantly longer in the SPC guide group than in the FH group (267.8 ± 45.5 min vs. 210.9 ± 44.5 min, P = 0.001). Other clinical parameters, such as the average bone mineral density (BMD), intraoperative blood loss, and postoperative hospital stay, were not significantly different. Oswestry disability index (ODI) and back pain visual analogue scale (VAS) scores were significantly improved in both groups compared with preoperatively. SPC guided screw placement was more accurate than the fluoroscopy-assisted FH technique for single-level MIDLF at L4/5. Patients undergoing SPC-guided screw placement can achieve similar clinical outcomes as the fluoroscopy-assisted FH technique.

Postoperative complications following Schwab-grade-I versus Schwab-grade-II PCO in treating severe rigid kyphoscoliosis patients: comparative matched-group outcomes with minimum 2-year follow-up.

BACKGROUND CONTEXT: Standard partial facetectomies, (Smith-Petersen Osteotomy, (SPO), (Schwab-grade-I) and complete facet resection also known as Ponte osteotomy, (PO), (Schwab-grade-II) are narrowly akin and collectively appreciated as posterior column shortening osteotomies (PCOs). The former is considered a gentler osteotomy grade than the latter. The spine literature provides very little information on their comparison regarding perioperative complications and major curve correction rate outcomes. PURPOSE: To determine whether Schwab-grade-I PCO (SPO) and Schwab-grade-II PCO (PO) are comparably safe in the surgical management of severe rigid scoliosis or kyphoscoliosis patients. STUDY DESIGN/SETTING: Retrospective single-center comparative clinical study. PATIENT SAMPLE: A total of 38 patients with severe rigid scoliosis or kyphoscoliosis were propensity score matched in this study, (SPO-treated); n=21 (55.30%) and (PO-treated); n=17 (44.70%), who underwent primary spinal deformity corrective surgery, respectively. OUTCOME MEASURES: Outcomes included demographics, baseline pulmonary functional outcomes, perioperative complications incidence, hospital costs, Oswestry disability index (ODI), and the Scoliosis Research Society-22 (SRS-22) questionnaire scores. METHODS: Following approval by the Institutional Review Board (IRB) of Beijing Chaoyang Hospital-Affiliated Capital Medical University in Beijing, out of a total of 82 consecutive surgical patients with complete data demonstrating severe and/or rigid spinal deformity, a pool of 38 of the 82 (46.3%) propensity-matched adult (≥18 years) patients with severe rigid scoliosis or kyphoscoliosis defined with a preoperative major curve magnitude of ≥80° on anteroposterior plain radiographs, and flexibility of <25% on bending plain radiographs who underwent primary spinal deformity corrective surgery were retrospectively evaluated. The patients were dichotomized into two osteotomy groups: standard (partial) facetectomy (SPO-treated), n=21 with an average age of 24.67 years, (Schwab-grade-I PCO) and complete facet excision, (PO-treated), (ie, Schwab-grade-II PCO), n=17 with an average age of 23.12 years. The minimum follow-up period was 2 years. Primary outcomes included baseline demographics and clinical features. Secondary outcomes included perioperative [intraoperative, immediate, and 2-year postoperative] complication rates. Tertiary outcomes included perioperative ODI and SRS-22 scores. Statistical analyses were carried out by Student t-test and Pearson's Chi-square test (Fisher's Exact Test), through Python statistical software package. Statistical significance was set at (p<.05). RESULTS: Of the 38 matched severe rigid scoliosis or kyphoscoliosis patients, 55.30% (n=21) were SPO-treated and 44.70% (n=17) were PO-treated patients, respectively. The overall average age of patients was 23.97 years, with a female incidence of 76.32%. Major curve correction rates were 49.19% and 57.40% in SPO-treated and PO-treated patients, respectively, (p>.05). Immediately following surgery, comparable overall complication rates of 28.57% (n=6/21) versus 29.41% (n=5/17) were observed in the SPO-treated and PO-treated patients, respectively, (p=.726). We observed incidences of 9.52%, (n=2/21) versus 5.88%, (n=1/17) for surgical intensive care unit (SICU) admission, and incidences of 4.76%, (n=1/21) versus 5.88%, (n=1/17) for cardiopulmonary events in SPO-treated versus PO-treated patients following corrective surgery, respectively, (p>.05). The incidences of neurological deficits in the SPO-treated and PO-treated patients were respectively, 14.29%, (n=3/21) versus 17.65%, (n=3/17) immediately following surgery, (p>.05), and 0.00%, (n=0/21) in SPO-treated versus 14.28%, (n=3/21) in PO-treated patients at ≥2 years postoperative, (p<.05). Among the three patients that reported neurological deficits in the PO-treated group at ≥2 years postoperative, two patients had pre-existing baseline neurological deficits. The ODI score in the PO-treated group was significantly inferior at a minimum 2-year follow-up, (p<.05). CONCLUSIONS: In the current study, both SPO-treated and PO-treated patients demonstrated statistically comparable surgical complications immediately following corrective surgery. Severe rigid kyphoscoliosis patients with preexisting baseline neurological deficits were more inclined to sustain neurological morbidity following corrective surgery. PCO corrective techniques are warranted as safe options for treating patients with severe rigid spine deformity phenotypes.

Biomechanical evaluation of multiple pelvic screws and multirod construct for the augmentation of lumbosacral junction in long spinal fusion surgery.

Background: Posterior long spinal fusion was the common procedure for adult spinal deformity (ASD). Although the application of sacropelvic fixation (SPF), the incidence of pseudoarthrosis and implant failure is still high in long spinal fusion extending to lumbosacral junction (LSJ). To address these mechanical complications, advanced SPF technique by multiple pelvic screws or multirod construct has been recommended. This was the first study to compare the biomechanical performance of combining multiple pelvic screws and multirod construct to other advanced SPF constructs for the augmentation of LSJ in long spinal fusion surgery through finite element (FE) analysis. Methods: An intact lumbopelvic FE model based on computed tomography images of a healthy adult male volunteer was constructed and validated. The intact model was modified to develop five instrumented models, all of which had bilateral pedicle screw (PS) fixation from L1 to S1 with posterior lumbar interbody fusion and different SPF constructs, including No-SPF, bilateral single S2-alar-iliac (S2AI) screw and single rod (SS-SR), bilateral multiple S2AI screws and single rod (MS-SR), bilateral single S2AI screw and multiple rods (SS-MR), and bilateral multiple S2AI screws and multiple rods (MS-MR). The range of motion (ROM) and stress on instrumentation, cages, sacrum, and S1 superior endplate (SEP) in flexion (FL), extension (EX), lateral bending (LB), and axial rotation (AR) were compared among models. Results: Compared with intact model and No-SPF, the ROM of global lumbopelvis, LSJ, and sacroiliac joint (SIJ) was decreased in SS-SR, MS-SR, SS-MR, and MS-MR in all directions. Compared with SS-SR, the ROM of global lumbopelvis and LSJ of MS-SR, SS-MR, and MS-MR further decreased, while the ROM of SIJ was only decreased in MS-SR and MS-MR. The stress on instrumentation, cages, S1-SEP, and sacrum decreased in SS-SR, compared with no-SPF. Compared with SS-SR, the stress in EX and AR further decreased in SS-MR and MS-SR. The most significantly decreased ROM and stress were observed in MS-MR. Conclusion: Both multiple pelvic screws and multirod construct could increase the mechanical stability of LSJ and reduce stress on instrumentation, cages, S1-SEP, and sacrum. The MS-MR construct was the most adequate to reduce the risk of lumbosacral pseudarthrosis, implant failure, and sacrum fracture. This study may provide surgeons with important evidence for the application of MS-MR construct in the clinical settings.

Comparison of Overall Complication Rates in VCR-Based vs Non-VCR-Based Corrective Techniques in Severe Rigid Kyphoscoliosis Patients: A Systematic Review and Meta-Analysis.

STUDY DESIGN: Systematic review and meta-analysis. OBJECTIVE: Compilation of complication outcomes data from the surgical management of severe rigid kyphoscoliosis patients using VCR-based vs non-VCR-based corrective maneuvers is lacking. This meta-analysis aimed to compare complication outcomes between those classified osteotomy approaches. METHODS: Thorough literature review and meta-analysis were conducted between January 2000 and September 2021. The selection criteria were studies: i) reporting major curve Cobb angle of ≥80° and flexibility of <25% or 30%; ii) comparing VCR or ≥ Type V Schwab osteotomy defined as VCR-based vs [non-VCR-based] techniques, (any osteotomy or technique other than VCR); iii) published in English with ≥10 patients; iv) reporting complication rates; and v) having minimum of 2-year follow-up. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated. Significance level was set at (P < .05). RESULTS: Of the 174 patients included, 52.30% (n = 91) and 47.70% (n = 83) were VCR-based and non-VCR-based, respectively. The incidence of dural tears/nerve injuries/significant intraoperative-neuromonitoring changes was significantly higher; [OR = 6.78, CI= (1.75 to 26.17), I2 = 0%, (P = .006)] in the VCR-based group than the non-VCR-based group. The 'overall surgical and medical' complication rate was significantly higher in the VCR-based group, [OR = 1.94, CI= (1.02 to 3.67), I2 = 31%, (P = .04)]. CONCLUSION: Both VCR-based and non-VCR-based surgical techniques for management of severe rigid scoliosis and kyphoscoliosis patients pose comparable overall surgical complication rates, while a significantly higher perioperative neurological complication incidence was associated with VCR-based technique compared to the non-VCR-based techniques. The VCR-based technique was associated with 6.78 times higher incidence of neurological complications compared to non-VCR-based techniques.

The Value of Three-Dimensional Printing Spine Model in Severe Spine Deformity Correction Surgery.

STUDY DESIGN: Retrospective case-control study. OBJECTIVE: We aimed to evaluate the value of 3-dimensional printing (3DP) spine model in the surgical treatment of severe spinal deformity since the prosperous development of 3DP technology. METHODS: Severe scoliosis or hyper-kyphosis patients underwent posterior fixation and fusion surgery using the 3DP spine models were reviewed (3DP group). Spinal deformity surgeries operated by free-hand screw implantation during the same period were selected as the control group after propensity score matching (PSM). The correction rate, pedicle screw accuracy, and complications were analyzed. Class A and B screws were defined as accurate according to Gertzbein and Robbins criteria. RESULTS: 35 patients were enrolled in the 3DP group and 35 matched cases were included in the control group. The perioperative baseline data and deformity correction rate were similar between both groups (P > .05). However, the operation time and blood loss were significantly less in the 3DP group (296.14 ± 66.18 min vs. 329.43 ± 67.16 min, 711.43 ± 552.28 mL vs. 1322.29 ± 828.23 mL, P < .05). More three-column osteotomies (Grade 3-6) were performed in the 3DP group (30/35, 85.7% vs. 21/35, 60.0%. P = .016). The screw placement accuracy was significantly higher in the 3DP group (422/582, 72.51% vs. 397/575, 69.04%. P = .024). The screw misplacement related complication rate was significantly higher in the free-hand group (6/35 vs. 1/35, P = .046). CONCLUSIONS: The study provided solid evidence that 3DP spine models can enhance surgeons' confidence in performing higher grade osteotomies and improve the safety and efficiency in severe spine deformity correction surgery. 3D printing technology has a good prospect in spinal deformity surgery.

Expert Consensus on Clinical Application of Lateral Lumbar Interbody Fusion: Results From a Modified Delphi Study.

STUDY DESIGN: Modified Delphi study. OBJECTIVE: The objective of this study was to establish expert consensus on the application of lateral lumbar interbody fusion (LLIF) by using the modified Delphi study. METHODS: From June 2019 to March 2020, Members of the Chinese Study Group for Lateral Lumbar Spine Surgery were selected to collect expert feedback using the modified Delphi method where 65 spine surgeons from all over China agreed to participate. Four rounds were performed: 1 face-to-face meeting and 3 subsequent survey rounds. The consensus was achieved with ≥a 70.0% agreement for each question. The recommendation of grade A was defined as ≥90.0% of the agreement for each question. The recommendation of grade B was defined as 80.0-89.9% of the agreement for each question. The recommendation of grade C was defined as 70.0-79.9% of the agreement for each question. RESULTS: A total of 65 experts formed a panelist group, and the number of questionnaires collected was 63, 59, and 62 in the 3 rounds. In total, 5 sections, 71 questions, and 382 items achieved consensus after the Delphi rounds including summary; preoperative evaluation; application at the lumbar spinal stenosis, lumbar disc herniation, lumbar spondylolisthesis, adult degenerative scoliosis, postoperative adjacent segmental degeneration, and revision surgery; complications; and postoperative follow-up evaluation of LLIF. CONCLUSION: The modified Delphi method was utilized to ascertain an expert consensus from the Chinese Study Group for Lateral Lumbar Spine Surgery to inform clinical decision-making in the application of LLIF. The salient grade A recommendations of the survey are enumerated.

Accuracy of cortical bone trajectory screw fixation guided by spinous process clamp guide in lumbosacral vertebrae: A cadaver study.

BACKGROUND: The purpose of this study was to access the accuracy of cortical bone trajectory screw placement guided by spinous process clamp (SPC). METHODS: Eight formalin-treated cadaveric lumbar specimens with T12-S1 were used. A total of 96 screws were implanted in eight lumbar specimens. RESULTS: In the freehand (FH) group, clinically acceptable placement (grade A and B) was 40 screws (83.3%), meanwhile 44 screws (91.7%) in the SPC guide group (p = 0.217). The grade A screws in the SPC guide group were much more than that in the FH group (n = 40 vs. n = 31, p = 0.036). The misplacement screws (grade C, D, and E) and proximal facet joint violation (FJV) in the SPC group was comparable to the FH group. CONCLUSIONS: This cadaveric study demonstrate that implanting CBT screws guided by SPC guide was more accuracy and reduces severe deviations in important directions.

Cortical screw placement with a spinous process clamp guide: a cadaver study accessing accuracy.

BACKGROUND AND OBJECTIVE: The Cortical Bone Trajectory (CBT) technique provides an alternative method for fixation in the lumbar spine in patients with osteoporosis. An accuracy CBT screw placement could improve mechanical stability and reduce complication rates. PURPOSE: The purpose of this study is to explore the accuracy of cortical screw placement with the application of implanted spinous process clip (SPC) guide. METHODS AND MATERIALS: Four lumbar specimens with T12-S1 were used to access the accuracy of the cortical screw. The SPC-guided planning screws were compared to the actual inserted screws by superimposing the vertebrae and screws preoperative and postoperative CT scans. According to preoperative planning, the SPC guide was adjusted to the appropriate posture to allow the K-wire drilling along the planned trajectory. Pre and postoperative 3D-CT reconstructions was used to evaluate the screw accuracy according to Gertzbein and Robbins classification. Intraclass correlation coefficients (ICCs) and Bland-Altman plots were used to examine SPC-guided agreements for CBT screw placement. RESULTS: A total of 48 screws were documented in the study. Clinically acceptable trajectory (grades A and B) was accessed in 100% of 48 screws in the planning screws group, and 93.8% of 48 screws in the inserted screws group (p = 0.242). The incidence of proximal facet joint violation (FJV) in the planning screws group (2.1%) was comparable to the inserted screws group (6.3%) (p = 0.617). The lateral angle and cranial angle of the planned screws (9.2 ± 1.8° and 22.8 ± 5.6°) were similar to inserted screws (9.1 ± 1.7° and 23.0 ± 5.1°, p = 0.662 and p = 0.760). Reliability evaluated by intraclass correlation coefficients and Bland-Altman showed good consistency in cranial angle and excellent results in lateral angle and distance of screw tip. CONCLUSIONS: Compared with preoperative planning screws and the actually inserted screws, the SPC guide could achieve reliable execution for cortical screw placement.

A nomogram for predicting screw loosening after single-level posterior lumbar interbody fusion utilizing cortical bone trajectory screw: A minimum 2-year follow-up study.

Purpose: This study aims to investigate the risk factors for screw loosening after single-level posterior lumbar interbody fusion (PLIF) utilizing cortical bone trajectory (CBT) screw and establish a nomogram for predicting screw loosening. Methods: A total of 79 patients (316 screws) who underwent single-level PLIF with CBT screw were included in the study. Preoperative, postoperative, and final follow-up demographic data, surgical data, and radiographic parameters were documented and analyzed to identify risk factors, and a predictive nomogram was established for screw loosening. The nomogram was assessed by concordance index (C-index), calibration plot, decision curve analysis (DCA), and internal validation. Results: The incidence of screw loosening was 26.6% in 79 patients and 11.4% in 316 screws. Multifactorial regression analysis confirmed that fixed to S1 (FS1, OR = 3.82, 95% CI 1.12-12.71, P = 0.029), the coronal angle of the screw (CA, OR = 1.07, 95% CI 1.01-1.14, P = 0.039), and cortical bone contacted layers (CBCLs, OR = 0.17, 95% CI 0.10-0.29, P < 0.001) were risk factors and incorporated in the nomogram for predicting screw loosening after single-level PLIF with a CBT screw. The C-index of the nomogram was 0.877 (95% CI 0.818-0.936), which demonstrated good predictive accuracy. The calibration plot indicated an acceptable calibration of the nomogram that also had a positive benefit in guiding treatment decisions. Conclusion: FS1, CA, and CBCLs are identified to be significant risk factors for screw loosening after single-level PLIF with the CBT technique. The nomogram we have established can be used to predict screw loosening and contribute to surgical decisions.

The outcome of enhanced recovery after surgery vs. a traditional pathway in adolescent idiopathic scoliosis surgery: A retrospective comparative study.

Objectives: The optimized enhanced recovery after surgery (ERAS) pathway for adolescent idiopathic scoliosis (AIS) patients has not been comprehensively described. The purpose of the study was to explore the feasibility and efficacy of an integral process of ERAS protocol in posterior spinal fusion (PSF) surgery for AIS patients without three-column osteotomy. Methods: Based on the inclusion and exclusion criteria, a total of 90 AIS patients who underwent PSF were enrolled in the study. Forty-five patients followed a traditional pathway (TP) perioperative care and 45 were treated with an ERAS protocol designed and implemented by a multidisciplinary team. Patient demographic, clinical information, surgical data, and radiographic parameters were collected and analyzed retrospectively. Results: There is no significant difference in age, gender, body mass index, preoperative hemoglobin level, Cobb angle, curve type, average correction rate, fusion segments, and screw number between ERAS group and TP group. Regarding the estimated blood loss (EBL), surgical duration, pain intensity, drainage duration, drainage volume, first ambulation time, postoperative length of stay (LOS), and the incidence of blood transfusion, they were significantly less in ERAS group than those of TP group. Conclusions: Based on our findings, we found that the implementation of a standard ERAS protocol in AIS correction surgery could result in less EBL, lower pain intensity, early ambulation, shorter LOS, and rapid rehabilitation. We recommend the widespread adoption of ERAS protocols in AIS surgery.

Hounsfield unit for assessing asymmetrical loss of vertebral bone mineral density and its correlation with curve severity in adolescent idiopathic scoliosis.

Background: Low bone mass concomitantly occurs in patients with adolescent idiopathic scoliosis (AIS) and can persist until skeletal maturity. The purpose of this study was to assess the asymmetrical loss of vertebral bone mineral density (vBMD) and its correlation with curve severity in patients with AIS using Hounsfield unit (HU) values measured from computed tomography scans. Methods: A total of 93 AIS patients were retrospectively recruited. The HU values of the vertebral body (VB-HU) and pedicle screw trajectory (PST-HU) were measured from four vertebrae above (Apex - 4) to four below (Apex + 4) the apical vertebra (Apex) of the major curve. The VB-HU and PST-HU at the upper end vertebra, Apex, and lower end vertebra within the concave and convex sides of the major and minor curves and stable vertebrae were obtained. Results: A significant correlation was found between the Cobb angle and VB-HU at the periapical levels of the major curve. VB-HU and PST-HU at periapical levels were significantly greater within the concavity than the convexity of both major and minor curves. The asymmetric ratios of VB-HU and PST-HU were significantly correlated with the major curve Cobb angle, peaked at the apex, and gradually diminished from the apex to the end vertebrae. The asymmetrical loss of vBMD aggravated with the progression of curve severity, presenting as VB-HU, significantly decreased within the convexity and insignificantly decreased within the concavity of the major curve. Conclusion: The asymmetrical loss of vBMD was associated with the progression of curve severity in AIS. For patients with severe AIS, the distraction of the pedicle screws at the concave side should be a priority in correcting the major curve, and supplemental anchors and larger-sized screws should be placed within the convex side around the apex of the major curve to reduce the risk of screw loosening after surgery.

Elasticity change of the paravertebral fascia and muscle in adolescent idiopathic scoliosis after posterior selective fusion surgery.

BACKGROUND: We sought to assess the elasticity change of the paravertebral fascia and muscle in adolescent idiopathic scoliosis patients with Lenke Type 1, 2, or 3 curves after posterior selective fusion surgery. METHODS: The shear wave elasticity imaging system was used to assess the elasticity of the thoracic paravertebral muscles and fascia both on the concave and convex sides. Three regions of interest, including the apex, upper end, and lower end of the main curve, were tested. FINDINGS: Ten female patients, with an average age of 16.6 ± 2.7 years old, were included. The average post-operation follow-up period was 9.0 ± 2.4 months. The Cobb angle was significantly corrected from 63.6 ± 12.0° to 10.7 ± 5.4° (p < 0.05). The length of the trunk increased from 40.4 ± 2.5 cm to 46.0 ± 2.8 cm (p < 0.05). The elasticity of deep fascia didn't show a significant change post-operation (p > 0.05). The elasticity of the paravertebral muscle on the concave side had a significant increase at the final follow-up (p < 0.05). The elasticity of the paravertebral muscle on the convex side also increased at the upper end (p < 0.05). The elasticity asymmetry of the deep fascia decreased, but the elasticity asymmetry of the paravertebral muscle increased at the upper end of the curve (p < 0.05). INTERPRETATION: The paravertebral muscle on the concave side is stiffer after surgery. Elastic asymmetry of paravertebral muscle increased and elastic asymmetry of the deep fascia decreased at the upper end of the curvature. Further study is needed to elucidate the mechanism by which the paravertebral soft tissue responds after surgery.

Low paraspinal lean muscle mass is an independent predictor of adjacent vertebral compression fractures after percutaneous kyphoplasty: A propensity score-matched case-control study.

Background: To investigate the relationship between paraspinal lean muscle mass and adjacent vertebral compression fracture (AVCF) after percutaneous kyphoplasty (PKP) for osteoporotic vertebral compression fracture (OVCF). Methods: The data of 272 patients who underwent two consecutive single-level PKP in our hospital from January 2017 to December 2019 were collected. 42 patients who met the inclusion and exclusion criteria were selected as AVCF group, and 42 propensity score-matched patients were selected as control group. There were 10 males and 32 females in each group; the ages were 75.55 ± 5.76 years and 75.60 ± 5.87 years, respectively. All patients underwent preoperative lumbar MRI. The total cross-sectional area (CSA), functional cross-sectional area (FCSA), cross-sectional area of vertebra index (CSA-VI), functional cross-sectional area of vertebra index (FCSA-VI) of the multifidus (MF), erector spinae (ES), psoas (PS), and paravertebral muscles (PVM) were measured. Other related parameters included preoperative bone mineral density (BMD), kyphotic angle (KA), anterior-to-posterior body height ratio (AP ratio), vertebral height restoration, and cement leakage into the disc. Logistic regression analysis was performed to find independent risk factors for AVCF using the parameters that were statistically significant in univariate analysis. Results: At L3 and L4 levels, the mean CSA, FCSA, and FCSA-VI of MF, ES, PVM and PS were significantly lower in the AVCF group. DeLong test indicated that the AUC of ES (0.806 vs. 0.900) and PVM (0.861 vs. 0.941) of FCSA-VI at L4 level were significantly greater than L3 level. In the AVCF group, patients had a significantly lower BMD (93.55 ± 14.99 HU vs. 106.31 ± 10.95 HU), a greater preoperative KA (16.02° ± 17.36° vs. 12.87° ± 6.58°), and a greater vertebral height restoration rate (20.4% ± 8.1% vs. 16.4% ± 10.0%, p = 0.026). Logistic regression analysis showed that PVM with lower FCSA-VI at L4 level (OR 0.830; 95% CI 0.760-0.906) and lower BMD (OR 0.928; 95% CI 0.891-0.966) were independent risk factors for AVCF after PKP. Conclusions: Low paraspinal lean muscle mass is an independent risk factor for AVCF after PKP. Surgeons should pay attention to evaluate the status of paraspinal muscle preoperatively. Postoperative reasonable nutrition, standardized anti-osteoporosis treatment, and back muscle exercise could reduce the incidence of AVCF.

Accuracy and safety of robot-assisted cortical bone trajectory screw placement: a comparison of robot-assisted technique with fluoroscopy-assisted approach.

OBJECTIVE: To compare the safety and accuracy of cortical bone trajectory screw placement between the robot-assisted and fluoroscopy-assisted approaches. METHODS: This retrospective study was conducted between November 2018 and June 2020, including 81 patients who underwent cortical bone trajectory (CBT) surgery for degenerative lumbar spine disease. CBT was performed by the same team of experienced surgeons. The patients were randomly divided into two groups-the fluoroscopy-assisted group (FA, 44 patients) and the robot-assisted group (RA, 37 patients). Robots for orthopedic surgery were used in the robot-assisted group, whereas conventional fluoroscopy-guided screw placement was used in the fluoroscopy-assisted group. The accuracy of screw placement and rate of superior facet joint violation were assessed using postoperative computed tomography (CT). The time of single screw placement, intraoperative blood loss, and radiation exposure to the surgical team were also recorded. The χ2 test and Student's t-test were used to analyze the significance of the variables (P < 0.05). RESULTS: A total of 376 screws were inserted in 81 patients, including 172 screws in the robot-assisted group and 204 pedicle screws in the fluoroscopy-assisted group. Screw placement accuracy was higher in the RA group (160, 93%) than in the FA group (169, 83%) (P = 0.003). The RA group had a lower violation of the superior facet joint than the FA group. The number of screws reaching grade 0 in the RA group (58, 78%) was more than that in the FA group (56, 64%) (P = 0.041). Screw placement time was longer in the FA group (7.25 ± 0.84 min) than in the RA group (5.58 ± 1.22 min, P < 0.001). The FA group had more intraoperative bleeding (273.41 ± 118.20 ml) than the RA group (248.65 ± 97.53 ml, P = 0.313). The radiation time of the FA group (0.43 ± 0.07 min) was longer than the RA group (0.37 ± 0.10 min, P = 0.001). Furthermore, the overall learning curve tended to decrease. CONCLUSIONS: Robot-assisted screw placement improves screw placement accuracy, shortens screw placement time, effectively improves surgical safety and efficiency, and reduces radiation exposure to the surgical team. In addition, the learning curve of robot-assisted screw placement is smooth and easy to operate.

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.

Mathematical Modeling and Nail Placement Accuracy Analysis of NF-1 Neurofibromatosis Scoliosis.

We have analyzed the arch root morphology, nail placement accuracy, degree of arch deformity, and three-dimensional Cobb angle in patients with NF scoliosis by CT 3D reconstruction. Likewise, we have thoroughly examined arch root morphology, nail placement accuracy, degree of arch deformity, and three-dimensional Cobb angle in patients with idiopathic scoliosis by CT 3D reconstruction. The results of the two groups were statistically analyzed and compared to assess the efficacy and other morphological differences between these groups. For this purpose, 276 patients with scoliosis, including 221 with idiopathic scoliosis and 16 with neurofibromatosis scoliosis, were treated in the hospital, which is from May 2008 to December 2016. The 16 patients with idiopathic scoliosis were matched with patients with neurofibromatosis, and the postoperative CT data were reconstructed in three dimensions, and the measurements included arch morphology, arch transverse diameter, arch-rib joint transverse diameter, three-dimensional coronal Cobb angle, and correction rate. The data of the two groups were statistically analyzed to compare the arch morphology, nail placement accuracy, and treatment effect between patients with NF and patients with AIS. Statistical analysis was performed to compare the differences between NF and AIS patients in terms of morphology, nail placement accuracy, and treatment outcome. The results showed that there were more severely deformed pedicles in NF patients than in idiopathic scoliosis, and the difference between them was statistically significant. Of the 142 screws placed in the NF group, 88 screws were in a good position, and the remaining 54 screws were misplaced.