Asian Spine Journal最新文献

Study design: Retrospective cohort study.

Purpose: To compare lumbar spine revision rates and postoperative complications among patients with concurrent hip osteoarthritis (OA) and lumbar spine pathology (LSP) who underwent lumbar fusion (LF) alone, LF before total hip arthroplasty (THA), or LF after THA.

Overview of literature: Few studies have examined how the sequence of THA and LF affects outcomes. One study found that performing THA first in patients with concurrent spine disease was associated with fewer subsequent surgeries, postoperative instability, and reduced opioid use. However, there is a lack of robust evidence on this topic.

Methods: A retrospective cohort study was conducted using the PearlDiver national database to compare patients with LSP treated with LF and hip OA treated with THA, categorized by surgical sequence: THA followed by LF (THA_LF) or LF followed by THA (LF_THA). Multivariable logistic regression was used to calculate adjusted odds ratios, adjusting for age, sex, region, Elixhauser comorbidity index, insurance plan, and diabetes status.

Results: A total of 70,265 patients met the inclusion criteria. At 5-year follow-up, lumbar revision rates were 8.6% in the LF_THA cohort and 8.4% in the THA_LF cohort. Compared with patients who underwent LF alone, the adjusted odds of lumbar revision were 5.59 times higher in LF_THA (p <0.001) and 2.61 times higher in THA_LF (p <0.001). Ninety-day outcomes varied among cohorts, with the LF_THA cohort demonstrating the highest odds of complications.

Conclusions: In this large national cohort, undergoing LF before THA was associated with increased odds of spinal revision and postoperative complications compared with undergoing THA first or LF alone.

As the population ages, the incidence of osteoporotic vertebral compression fractures (OVCF) continues to rise, leading to an increased use of cement augmentation procedures. Consequently, clinicians are more frequently encountering patients with cement-augmented vertebrae who require additional spinal instrumentation. However, pedicle screw insertion into previously cement-augmented vertebral bodies remains technically challenging. This study aimed to describe a simple and reproducible technique for a safe and effective insertion of a pedicle screw into cement-augmented vertebral bodies. Ten patients with a history of cement augmentation for OVCF, who subsequently developed severe kyphotic deformity or degenerative spinal disease requiring posterior instrumentation, were treated using this technique. Pedicle screws were successfully inserted into all cement-augmented vertebrae without any intraoperative complications, including drill tip breakage, cement dislodgement, or anterior wall violation. In conclusion, pedicle screw insertion into cementaugmented vertebral bodies can be performed safely and reliably. This method may simplify a procedure that has traditionally been regarded as technically demanding.

Surgical management of adult spinal deformity (ASD) is complex, and traditional open surgery is associated with significant perioperative morbidity. These issues have catalyzed a paradigm shift toward enabling techniques and technologies designed to minimize iatrogenic injuries while achieving surgical goals. This comprehensive review synthesizes the current applications and future perspectives of these techniques and technological advancements. We examine the evolution of minimally invasive surgery (MIS), including the use of selection algorithms such as MISDEF-2 (minimally invasive spinal deformity surgery algorithm-2) and the "ceiling effect" of MIS correction. We discuss advanced techniques, such as anterior column realignment, which offers significant corrective power with less morbidity, and highlight evidence showing patient-reported outcomes comparable to those of open surgery. This review also analyzes the impact of robotic assistance and navigation, which provide quantifiable improvements in instrumentation accuracy (e.g., pedicle and S2-alar-iliac screws) and safety by reducing complications, such as facet joint violations. Furthermore, we explore the increased use of patient-specific implants, including pre-contoured patient-specific rods and three-dimensional printed interbody cages, which enhance the precise execution of preoperative plans. Finally, we discuss future directions, including the integration of these tools into efficient workflows, such as single-position surgery, and the emergence of augmented reality and predictive analytics. The synergistic integration of these technologies promises to establish safer, more precise, and personalized care for patients with ASD.

Study design: Prospective double-blinded randomized controlled trial.

Purpose: This study aimed to compare the effect of adding dexmedetomidine or morphine to 0.2% ropivacaine on total postoperative opioid consumption and to compare time to first rescue analgesia, Visual Analog Scale (VAS) scores, and side effect profiles between groups.

Overview of literature: Spine fusion surgery involves cutting or retracting the paraspinal muscles, causing moderate to severe postoperative pain. Neuroanesthesia aims to ensure adequate safety and analgesia, thereby facilitating immediate postoperative neurological examination, mobilization, and early hospital discharge.

Methods: A double-blinded, randomized controlled trial was conducted involving 66 consenting patients upon obtaining approval from the Institutional Ethics Committee. Patients were randomly allocated into three groups (ropivacaine [R], ropivacaine with dexmedetomidine [RD], and ropivacaine with morphine [RM], 22 patients per group). The operating surgeon administered the allocated study drug at the end of surgery according to group assignment.

Results: All the groups were comparable in terms of demographic characteristics, American Society of Anesthesiologists class, and number of spine segments operated on. Mean total postoperative opioid consumption, time to first request for rescue analgesia, and total VAS score were significantly lower in groups RD and RM compared with group R, and in group RM compared with group RD. Similar results were observed when patients were analyzed based on the number of spinal segments operated on.

Conclusions: Morphine as an adjuvant to ropivacaine showed superior efficacy compared with dexmedetomidine-ropivacaine or ropivacaine alone in patients undergoing elective thoracolumbar spine fusion surgery.

Study design: Retrospective cohort study.

Purpose: To identify whether the presence and features of epidural metastases are risk factors for metastatic spinal cord compression (MSCC).

Overview of literature: Several factors are associated with the development of MSCC in patients with spinal metastases. However, the relationship between epidural metastasis and the development of MSCC is not well understood.

Methods: Among patients with spinal metastases at the spinal cord level treated at a single institution from 2017 to 2023, 191 cases (age: 66.4±12.9 years; sex: 120 male patients) were studied. We defined MSCC as a decrease of one or more grades in the American Spinal Injury Association (ASIA) impairment scale due to spinal metastases. Patients were diagnosed with epidural metastasis at the level of spinal metastasis. When the features of epidural metastases could be evaluated, the epidural spinal cord compression (ESCC) scale and circumferential angle of spinal cord compression (CASCC) were assessed. The risk factors for developing MSCC and high-risk epidural metastases were analyzed.

Results: Of the patients with spinal metastases who developed MSCC during follow-up, 97.6% had epidural metastases before the onset of MSCC. Multivariate logistic regression analysis identified the presence of epidural metastasis as an independent risk factor for MSCC. In patients with evaluable epidural metastases, multivariate logistic regression analysis identified the ESCC scale and CASCC as high-risk factors. The cutoffs were determined to be 3 for the ESCC scale and 180° for CASCC.

Conclusions: Epidural metastasis was identified as a risk factor for MSCC in patients with spinal metastases. Additionally, epidural metastases in those with an ESCC scale of 3 and a CASCC greater than 180° were categorized as high-risk tumors.

Study design: A retrospective study.

Purpose: To develop a nomogram to predict functional independence (FI) in patients undergoing lumbosacral spine surgery (LSSS).

Overview of literature: LSSS aims to improve functional outcomes and restore activities of daily living. We hypothesized that demographic, clinical, surgical, and neurological characteristics could be used to predict FI, as defined by the Barthel index (BI) scores.

Methods: The medical records of patients who underwent LSSS between October 2023 and September 2024 were reviewed. Univariate and multivariate logistic regression analyses were used to construct a predictive nomogram. Model performance was assessed using receiver operating characteristic curve analysis for discrimination and a bootstrap-based plot for calibration. Decision curve analysis and the Youden index were used to determine the optimal threshold probability for identifying patients requiring additional rehabilitation.

Results: The study included 111 patients (35 men and 76 women; mean age, 63.66±11.37 years), of whom 68 (61.26%) achieved FI. The nomogram, incorporating preoperative BI score, hospital stay <7 days, and absence of metabolic comorbidities and postoperative anemia, demonstrated excellent discrimination (area under the receiver operating characteristic curve=0.91; 95% confidence interval, 0.84- 0.98) and good calibration with the goodness-of-fit test (p>0.05). The optimal threshold probability cutoff was 0.58, with a sensitivity of 84% and specificity of 88%. This tool demonstrated excellent discriminative ability between patients who required further rehabilitation and those who did not, with a Youden index of 0.71.

Conclusions: This nomogram exhibited excellent discrimination and good calibration and could serve as a predictive tool for FI on the day of hospital discharge. Its application may support discharge planning and facilitate patient stratification to optimize postoperative rehabilitation.

Lumbar endoscopic unilateral laminotomy for bilateral decompression (LE-ULBD) is a minimally invasive procedure designed to treat lumbar spinal stenosis. While traditional uniportal endoscopic decompression already reduces tissue damage and promotes faster recovery compared to open surgery, this work introduces standardized terminology and specific endoscope-camera maneuvers to improve visualization and precision during both ipsilateral and contralateral decompression. By describing endoscope ("shaft") and camera head ("optic") rotations in a degree-degree format (e.g., 0-0, 90-0, 135-135, 180-180), the technique allows reproducible, targeted access to key anatomical areas while minimizing unnecessary bone removal. This systematic approach addresses the steep learning curve and technical intricacies of lumbar endoscopy, aiding intraoperative communication and potentially decreasing complications from inadequate decompression or poor visualization. The method aims to improve training, safety, and consistency of outcomes in endoscopic lumbar decompression procedures stenosis.

Study design: This is a finite element study.

Purpose: To identify optimal trajectory, screw size, and screw shape using the finite element method.

Overview of literature: Patients with diffuse idiopathic skeletal hyperostosis often develop spinal instability after fractures due to ankylosis and bone fragility. We developed single or double endplate penetrating screw trajectory (SEPST/DEPST) to improve fixation strength by penetrating the vertebral endplate. However, the optimal screw length, diameter, and shape remain unclear.

Methods: Finite element models of T12 and L1 were constructed from computed tomography images of osteoporotic patients. Three analyses were conducted: (1) the impact of various screw diameters with DEPST, (2) a comparison of fixation strength between short DEPST (S-DEPST), which penetrates the posterolateral endplate, and conventional DEPST (C-DEPST), and (3) a comparison between conventional cancellous thread screws (CTS) and endplate screws (ETS). Pullout strength (POS) was measured in all analyses. Vertebral motion angle (VMA) of the lower instrumented vertebra (LIV) was measured in analyses (2) and (3), and the four-directional load test (4DLT) was performed in analysis (2).

Results: Larger screw diameters with DEPST correlated with elevated POS. S-DEPST demonstrated significantly better fixation strength with a POS 1.46 times higher than C-DEPST and 2.5 times higher than traditional trajectories. S-DEPST also demonstrated higher fixation in all directions in 4DLT. However, no significant difference was observed in the VMA of LIV. ETS demonstrated slightly higher fixation than CTS, but the difference was not statistically significant.

Conclusions: Fixation strength improved with larger screw diameters in DEPST. S-DEPST provided additional fixation due to rim penetration. ETS may offer a higher fixation strength and warrants further validation.

Study design: Retrospective cohort study.

Purpose: This study aimed to (1) determine the incidence of lateral fusion following single-level oblique lateral interbody fusion (OLIF); (2) identify risk factors associated with the development of lateral fusion; (3) evaluate the effect of different fusion patterns on interbody cage subsidence rates; and (4) assess whether fusion patterns influence postoperative clinical outcomes.

Overview of literature: Fusion characteristics following OLIF differ from those seen in conventional transforaminal lumbar interbody fusion, most notably due to lateral fusion marked by extra-vertebral bony bridging (EVB). EVB may develop early postoperatively, suggesting a potential mechanism for early interbody fusion.

Methods: This retrospective cohort study included 153 single-level OLIF cases between January 2016 and December 2023. Postoperative computed tomography was used to classify patients into central fusion, lateral fusion, and non-fusion groups. Demographic, surgical, and radiographic parameters-including osteophyte grade, Hounsfield unit (HU) values, and cage positioning-were analyzed to identify factors affecting fusion. Cage subsidence and clinical outcomes (Oswestry Disability Index [ODI], Visual Analog Scale) were compared across groups.

Results: Lateral fusion occurred in 39.9% of cases, central in 56.9%, and non-fusion in 3.2%. Preoperative osteophytes and higher HU values were associated with lateral fusion (p<0.001). OLIF with standalone cages (OLIF-SA) had a significantly higher lateral fusion rate than OLIF with posterior screw fixation (OLIF-PS) (p=0.002). Smoking was a significant risk factor for non-fusion (p=0.005). No significant difference in cage subsidence was observed between central and lateral fusion, but non-fusion showed more severe subsidence. Clinical outcomes improved across fusion groups, though non-fusion cases had worse ODI scores at follow-up.

Conclusions: Lateral fusion is a distinct OLIF feature influenced by osteophytes, bone density, and fixation type. It does not negatively affect cage subsidence or outcomes, but solid fusion remains essential for recovery. These findings enhance understanding of OLIF fusion and may guide surgical planning.

The spinal instability neoplastic score (SINS) is used to evaluate spinal stability in patients with metastatic vertebrae and to guide treatment selection. SINSs of 13-18 indicate instability typically requiring surgery, while SINSs of 1-6 indicate stability and suitability for radiotherapy. However, the optimal approach for patients with SINSs of 7-12 remains unclear. This systematic review aimed to determine the optimal primary treatment for patients with intermediate SINSs (7-12) and potentially unstable metastatic vertebrae. A systematic literature search was conducted in PubMed, Embase, and Scopus, following the Preferred Reporting Items for Systematic reviews and Meta-analyses (PRISMA) guidelines. Twenty-six studies were included in this review (three A-class and 23 B-class). The A-class studies showed better outcomes with surgery±radiotherapy than radiotherapy alone. Two B-class studies indicated that patients with SINSs ≥10 more frequently underwent surgery, and one study found surgery was less effective for SINSs ≤9. Four studies showed good outcomes of surgery. In another study, 30% of patients became unstable after radiotherapy. In four studies, vertebral compression fractures developed in 20%-30% of patients after stereotactic body radiation therapy or stereotactic ablative body radiotherapy. One study showed that SINSs of 7-12 were correlated with radiotherapy failure, while another study found no such association. This systematic review suggests that surgical intervention alone or in combination with radiation may be superior for patients with SINSs of 7-12 and metastatic spinal tumors. The SINS 7-12 category might be divided into subgroups where surgery or radiotherapy is optimal. SINS ≥10 may indicate a need for surgery, and individual SINS components could be predictive. Further research is warranted to obtain more definitive evidence.