Journal of neurosurgery. Spine最新文献

Objective: Posterior cervical foraminotomy (PCF) for the treatment of radiculopathy can be performed via open, minimally invasive (MIS), or more recently emerging endoscopic approaches. Although proponents of endoscopy cite decreased postoperative pain as an advantage compared with open or MIS approaches, few studies have been performed to evaluate this outcome.

Methods: The authors retrospectively identified all patients undergoing PCF at a single institution from January 1, 2015, to June 1, 2024. Patients were stratified by operative approach (open, MIS, or uniportal endoscopic). The primary outcome was opioid consumption at 6 weeks, 3 months, and 6 months postoperatively, as well as cumulative opioid consumption in morphine milligram equivalents (MME) at each time interval. Secondary outcomes included short-term perioperative outcomes such as complications, operative duration, pain relief, and reoperation.

Results: One hundred thirty-eight patients met inclusion criteria, of whom 37 underwent open, 67 underwent MIS, and 34 underwent uniportal endoscopic procedures. Patients undergoing MIS and endoscopic approaches had lower rates of opioid use at 6 weeks compared with open approaches (relative risk 0.51 and 0.39, respectively). Endoscopic procedures were associated with lower total opioid MME within 6 weeks than both MIS and open procedures (238.4 vs 479.4 vs 753.8), although MIS and endoscopic procedures had similar rates of opioid use at 6 weeks. A subgroup analysis of a propensity score-matched cohort based on preoperative demographic data revealed a similar association between operative approach and total MME, although there were no significant differences between the cohorts in the proportion of patients using opioids at any of the follow-up intervals.

Conclusions: In this retrospective analysis, both endoscopic and MIS PCF were associated with lower overall rates and amount of opioid use with similar rates of short-term complications, reoperations, and pain relief as open approaches.

Objective: Although the mainstay of treatment for lumbar spondylolysis is nonoperative management with activity modification, a sizeable portion of patients will go on to nonunion. The growing use of robotic surgical guidance can allow for placement of pars screws through percutaneous incisions. The objective of this case series was to report on the largest series of adolescent patients with lumbar spondylolysis treated with robot-assisted pars repair to date.

Methods: A retrospective review of a prospectively collected database was performed for all adolescent patients (aged 13-25 years) who underwent pars repairs for treatment of spondylolysis with a single-screw technique. Patient demographic, surgical, and postoperative course information was collected and reported.

Results: Nine patients who underwent robotic pars repair were identified. The mean ± SD duration of activity cessation at initial surgical consultation was 8.6 ± 10.6 months. Seven patients underwent bilateral pars repairs and 2 underwent unilateral pars repairs. With a mean ± SD follow-up of 11.4 ± 9.1 months, 78% of patients had either returned to their baseline activity or were cleared for return to sport at the time of final follow-up.

Conclusions: For patients who fail nonoperative management, robot-assisted pars repair can be a safe and effective treatment option to allow return to activity in as little as 8 weeks. A single screw placed in a lag-by-technique fashion may be as clinically efficacious as open debridement and bone grafting described in prior literature.

Objective: The aim of this study was to investigate the association of home socioeconomic status (SES) with days at home and survival after treatment of spinal metastases.

Methods: This population cohort study included all patients in the Ontario Cancer Registry treated from 2007 to 2019 with surgery or radiation therapy (RT) for spinal metastasis. Ordinal categories of SES (SES1-SES5) were defined using home neighborhood material deprivation scores. Outcomes included adjusted median differences (aMD) in the number of days at home and adjusted hazard ratios (aHRs) of mortality for patients of differing SES. Secondary care access outcomes included receiving stereotactic body RT for treatment, the timing of palliative care initiation, and the distance from home to the nearest cancer center.

Results: There were 35,896 patients (55% male, mean age 64.4 years) identified; 7397 (21%) resided in relatively resource-deprived neighborhoods and 7080 (20%) resided in relatively resource-affluent neighborhoods. Patients living in the lowest SES neighborhoods had the fewest days at home (SES1 vs SES5, aMD -47) and shortest survival (SES1 vs SES5, aHR 1.14). There was significant mediation attributable to differences in primary cancer (days at home [15.6%], survival [25.7%]) and frailty (days at home [5.9%], survival [7.7%]) between neighborhood SES. Patients residing in lower SES neighborhoods were less often treated with stereotactic body RT (adjusted OR 0.38), had later initiation of palliative care (aHR 0.94), and lived farther from cancer centers (adjusted mean difference 16.5 km).

Conclusions: Patients with spinal metastases living in lower SES neighborhoods had fewer days at home and shorter survival, which was partially mediated by differences in primary cancer and possibly posttreatment access to oncology care. These findings will support advocacy efforts championing equity in cancer care.

Objective: The prevalence of degenerative lumbar spondylolisthesis in older adults is increasing, yet the factors influencing surgical outcomes remain unclear. The authors' study used a machine learning approach to identify outcome clusters among older patients operated on for grade I lumbar spondylolisthesis.

Methods: The authors analyzed data from the prospective Quality Outcomes Database (QOD) registry for patients aged ≥ 65 years who underwent surgery for grade I degenerative lumbar spondylolisthesis. Principal components analysis was used to generate a composite outcome score from 5 patient-reported outcomes (PROs) collected 24 months postoperatively. Subsequently, K-means clustering was used to stratify patients by outcome, with the optimal number of clusters decided by silhouette scoring. Multivariable logistic regression and Boruta feature selection were used to assess variable importance.

Results: Of 608 total patients, 233 were at least 65 years of age and met 24-month follow-up. K-means clustering identified two distinct groups: cluster 1 corresponded to more optimal outcomes (less pain and disability, higher satisfaction and quality of life), and cluster 2 corresponded to suboptimal outcomes. Cluster 1 had significantly greater improvements across all PROs at 24 months (p < 0.001), with 87.1% achieving the minimal clinically important difference (MCID) across both EQ-5D and Oswestry Disability Index (ODI) scores versus 48.8% in cluster 2 (p < 0.001). Clusters were similar in age (mean 72.5 vs 73.4 years, p = 0.24), but cluster 1 had lower baseline back and leg pain scores. Notably, patients in the optimal outcomes cluster were significantly more likely to have received a fusion procedure (70.7% vs 51.2%, p = 0.003). In logistic regression predictor analysis, lower baseline Numerical Rating Scale (NRS)-back pain score (OR 0.70, 95% CI 0.50-0.98, p = 0.04) and addition of fusion (OR 1.70, 95% CI 1.24-2.33, p = 0.001) were significant independent predictors of optimal outcomes, which was subsequently confirmed in Boruta analysis.

Conclusions: The authors' analysis of older (≥ 65 years old) patients undergoing surgery for grade I spondylolisthesis revealed two distinct clusters: one with optimal and the other with suboptimal outcomes. The addition of fusion to a procedure was associated with superior outcomes, as patients who received fusion had a 70% increase in the odds of reaching an optimal outcome. Age was not significantly associated with outcome, implying that there is no clear cutoff for surgical eligibility in older patients. These findings may inform decision-making between decompression alone versus decompression with fusion in older patients.

Objective: The aim of this study was to evaluate the clinical and biomechanical effects of distinct anterolateral screw placement angles in oblique lumbar interbody fusion combined with anterolateral fixation (OLIF-AF), focusing on cage subsidence (CS) incidence, spinal stability, and optimal fixation strategies.

Methods: Patients who underwent OLIF-AF at a single center from December 2017 to November 2023 were retrospectively analyzed. Patients were divided into 4 groups (G0, G1, G2, and G3) based on the coronal plane angle (CPA) and relative horizontal plane angle. Preoperative and 1- or 3-day, 3-month, and 12-month postoperative radiological and clinical data were collected. A validated L4-5 finite element model simulated 4 screw configurations under 6 loading conditions.

Results: Eighty patients (49 female, mean age 64.5 ± 7.1 years) were included in the analysis (28, 23, 15, and 14 patients in groups G0, G1, G2, and G3, respectively). CS occurred in 48.75% of patients, with significantly higher rates in the G2 (86.67%) and G3 (71.43%) versus G0 (28.57%) and G1 (34.78%) (p < 0.05) groups. Compared with parallel CPA groups (G0 and G1), nonparallel CPA groups (G2 and G3) exhibited greater disc height (DH) reduction (ΔDH range 3.1-3.4 mm vs 1.4-2.0 mm, p < 0.05), higher cage stress (range 55.50-57.29 MPa vs 53.45-54.96 MPa), increased displacement (range 73.62-78.28 × 10-2 mm vs 72.21-72.37 × 10-2 mm), and elevated range of motion (ROM) in flexion. Clinical scores (visual analog scale and Oswestry Disability Index) were not different between groups.

Conclusions: OLIF-AF with parallel screw placement in the coronal plane (G0 and G1) reduced CS risk and enhanced biomechanical stability by minimizing cage stress, displacement, and ROM. Horizontal screw bifurcation (G1 vs G0) did not demonstrate a statistically significant association with CS risk. Furthermore, there were no significant differences in fusion rates or clinical outcome measurements at different angles of AF.

Objective: Although minimally invasive techniques are established in thoracolumbar spine surgery, their benefit and applicability in cervical spine surgery still require further validation. This study aimed to investigate feasibility and screw accuracy, as well as paraspinal muscle atrophy, in the authors' initial patient cohort of subaxial percutaneous navigated cervical screw-rod instrumentation through a retrospective matched-patient analysis.

Methods: The patients of the percutaneous group (PG) (n = 20) were matched with the patients of the conventional group (CG) who underwent the midline approach (n = 20) on the basis of total instrumented segments, level of instrumentation, age, and sex. Pedicle screw accuracy was assessed using the Bredow classification and cross-sectional muscle areas were compared preoperatively and at a minimum follow-up of 60 days.

Results: Surgical indications were primarily degenerative in the CG (70%) and more diverse in the PG (40% degenerative, 35% oncological, and 20% traumatic). The percutaneous system was more frequently used in combined anterior-posterior approaches (50% PG vs 35% CG). Skin incision to navigation time was significantly shorter in the PG (mean ± SD 14 ± 15 minutes vs 44 ± 23 minutes in the CG), while screw placement time and clinically acceptable postoperative screw accuracy (88% PG vs 95% CG) were comparable. After a median follow-up of 140 days, muscle area change was without relevant differences (99.1% PG vs 93.7% CG), and no neurovascular injuries occurred in either group.

Conclusions: Percutaneous cervical screw-rod instrumentation using navigated pedicle screws is a versatile tool offering comparable accuracy. Besides the advantages of shorter preparation time and applicability in combined approaches, the real benefits of muscle preservation need to be proven in larger prospective patient cohorts.

Objective: The objective of this study was to develop and test the ability of a novel multivariate model to predict outcomes following minimally invasive transforaminal lumbar interbody fusion (TLIF) for degenerative spondylolisthesis at the L4-5 segment, and conduct internal validation of the proposed models for preoperative patient selection and to improve postoperative outcomes.

Methods: The authors conducted a retrospective analysis of a prospectively collected database. One hundred ninety-one consecutive patients undergoing TLIF on the L4-5 segment for symptomatic degenerative spondylolisthesis were prospectively enrolled and followed for 1 year. A comprehensive patient clinical and radiological assessment was performed at baseline and 12 months postoperatively. Regression mathematical modeling of preoperative variables was used to create the prognostic model of clinical outcomes (Oswestry Disability Index [ODI] and 36-Item Short-Form Health Survey [SF-36]). To predict the clinical outcome, 3 models were identified: 1) y0, based on the postoperative ODI score; 2) y1, based on the postoperative SF-36 Physical Component Summary (PCS) score; and 3) y2, based on the SF-36 Mental Component Summary (MCS) score. The following criteria were chosen as independent variables: age, BMI, duration of symptoms, presence of motor deficit, preoperative SF-36 PCS, preoperative SF-36 MCS, preoperative ODI score, preoperative back pain, preoperative leg pain, preoperative lumbar lordosis, preoperative interbody space height, preoperative sagittal angle, preoperative linear translation, intervertebral disc degeneration, facet joint degeneration, value of the apparent diffusion coefficient, and facet angle on the operative side.

Results: All patient-reported outcomes improved postoperatively (median, baseline vs 12 months): ODI score from 72% to 20% (p = 0.01), visual analog scale (VAS) back pain score from 78 to 24 mm (p = 0.02), VAS leg pain score from 92 to 14 mm (p = 0.01), SF-36 PCS score from 26.13 to 41.24 (p = 0.03), and SF-36 MCS score from 22.46 to 46.27 (p = 0.01). Reoperations occurred in 6 patients (3.1%), 9 (4.7%) were readmitted within 30 days of surgery, 168 (88.0%) returned to work, and 24 (12.6%) experienced an unplanned outcome (back pain and/or lower extremity pain > 20 mm according to the VAS, > 20 points on the ODI, a reoperation, or a readmission). These results suggest that the independent preoperative variables determined by radiography and MRI allow the prediction of the clinical outcome, but they have differing roles and dominance depending on the developed predictive model.

Conclusions: The predictive regression models that were developed in this study using these data can improve preoperative risk counseling and patient selection for minimally invasive TLIF surgery at the L4-5 segment.

Objective: Achieving and maintaining adequate segmental lumbar lordosis through anterior lumbar interbody fusion (ALIF) has been associated with favorable clinical outcomes. However, preoperative and immediate postoperative factors predicting changes in segmental alignment have not been established for ALIF.

Methods: Adults who underwent L5-S1 ALIF surgery for degenerative disc disease at a single institution between 2017 and 2022 were included. Multivariate stepwise linear regression analyses were performed to identify modifiable demographic, surgical, and alignment parameters that were predictive of 6-week to 1-year postoperative L5-S1 segmental lordosis loss. Next, multivariate logistic regression analyses were performed to evaluate the association between segmental loss and postoperative mechanical complications. Finally, multivariate logistic regression and receiver operating characteristic (ROC) curve analyses were performed to establish lower and upper thresholds for 6-week postoperative L5-S1 segmental lordosis that mitigated the need for revision surgery and segmental lordosis loss, respectively. Similar thresholds were established for low (< 45°), average (45°-60°), and high (> 60°) pelvic incidence (PI) categories as well.

Results: Among 94 patients, the mean age was 50.2 years, 57% were female, and the mean Charlson Comorbidity Index score was 1.4. Radiographically, patients had 7.6° L5-S1 lordotic correction (p < 0.001) and 10.2-mm L5-S1 anterior disc height increase (p < 0.001) after their ALIF surgery, and these changes were maintained to 1 year postoperatively. Stepwise regression revealed that baseline obesity (coefficient = -2.2, p = 0.047), lack of posterior fixation (coefficient = -2.4, p = 0.045), and larger correction in L5-S1 lordosis (coefficient = -0.4, p < 0.001) were independently associated with postoperative L5-S1 segmental lordosis loss. Cage subsidence was associated with higher odds of postoperative segmental loss (OR 1.2, p = 0.017). ROC curve analyses identified a 6-week postoperative L5-S1 segmental lordosis range of 21.6° to 26.8° (low PI 19.0°-24.8°, average PI 21.0°-26.4°, and high PI 24.1°-28.7°) as that which minimized loss of lordotic correction and the need for revision surgery over a 1-year follow-up period.

Conclusions: ALIF offers powerful restoration of segmental alignment that is maintained after surgery. The extent of subsequent loss can be predicted by baseline obesity, the presence of posterior instrumentation, and the degree of achieved lordotic correction. Preoperative surgical planning should consider correcting L5-S1 segmental lordosis to between the thresholds defined in this study to mitigate the risk of postoperative mechanical complications.

Objective: With the advent of bundled payments in spine surgery, there is increasing emphasis on value-based care. Although there is substantial literature on economies of scale in total joint arthroplasty, there remains a paucity of literature in spine surgery. The purpose of this study was to assess the impact of hospital volume on cost, length of stay (LOS), and discharge destination after elective inpatient spine surgery procedures in a Medicare population.

Methods: The 2019 Medicare Provider Analysis and Review Limited Data Set and Centers for Medicare and Medicaid Services 2019 Impact File were used in this study. Diagnosis-related group codes were used to identify 5 spine surgery cohorts consisting of nonfusion surgery, cervical fusion, noncervical fusion, anterior-posterior fusion, and complex fusion. Elective non-Medicare Advantage patients were included (n = 142,617). Patients were grouped according to low (1-100 cases; n = 51,685 [36%]), medium (101-200 cases; n = 44,145 [31%]), and high (≥ 201 cases; n = 46,787 [33%]) hospital volume. Hospital costs were calculated using cost-to-charge ratios. Multivariate models were created to evaluate associations between hospital volume and total hospital cost, hospital LOS, and discharge destination, controlling for confounders (type of surgery, complications, demographics, comorbidities, surgical details, and hospital details).

Results: In the univariate analysis of primary outcomes, high-volume spine centers were associated with greater cost (p < 0.001) and longer LOS (p < 0.001), and medium-volume spine centers were associated with a lower incidence of nonhome discharge (p < 0.001), compared with low-volume hospitals. However, in the multivariate analysis, increasing hospital volume was associated with decreasing cost (medium volume -$882 vs high volume -$1764, p < 0.001), decreasing LOS (medium volume -0.066 days vs high volume -0.132 days, p < 0.001), and decreasing risk of nonhome discharge (adjusted OR 0.809 [95% CI 0.783-0.836], p < 0.001 for medium volume; 0.746 [95% CI 0.721-0.772], p < 0.001 for high volume).

Conclusions: Increased hospital volume was independently associated with lower costs, shorter LOS, and decreased risk of nonhome discharge after elective inpatient spine surgery. High-volume centers might benefit from economies of scale and lean methodology practices that should be studied to improve value on a national level. Small and medium hospitals could be disproportionately impacted by declining Medicare reimbursements. Further study is necessary to provide fair reimbursement adjustments as bundled payments for spine surgery are introduced.

Objective: This study aimed to determine minimum clinically important difference (MCID) values for dysphagia using the Eating Assessment Tool-10 (EAT-10) in patients undergoing anterior cervical surgery, focusing on early dissatisfaction and later satisfaction thresholds to guide clinical decisions.

Methods: Data were prospectively collected from patients undergoing anterior cervical surgery across three institutions from 2016 to 2024. Dysphagia severity was assessed preoperatively and at various postoperative stages up to 1 year using EAT-10. The inverse probability of treatment weighting was used to control for confounding variables. The retrospective study of patient data employed two analytical phases: the first phase examined the relationship between dissatisfaction at 3 months (indicated by a North American Spine Society satisfaction score > 2) and changes in EAT-10 scores from baseline to peak (i.e., worst) postoperative scores; the second phase focused on recovery, comparing changes in EAT-10 scores from peak postoperative scores to 12 months against satisfaction (score < 2) at 12 months.

Results: The mean ± SD baseline EAT-10 score for the 1463 patients included in the study was 1.5 ± 4.7 and the mean peak score was 5.2 ± 7.4. The patients underwent anterior cervical discectomy and fusion (90%), arthroplasty (6%), or corpectomy (4%); a hybrid procedure was used in 1%. The phase 1 analysis indicated that a 4-point increase in EAT-10 score was a threshold for significant postoperative dissatisfaction in those without baseline dysphagia, with much higher thresholds observed in patients with any baseline dysphagia. In phase 2, among patients with baseline EAT-10 scores < 3 who experienced an increase to EAT-10 score ≥ 8 postoperatively, a subsequent decrease of 9 points by 12 months was necessary to report satisfaction. For patients with baseline scores 3-8 whose postoperative scores rose to ≥ 8, a subsequent decrease of 15 points was necessary for satisfaction. Patients with initial scores of ≥ 8 who did not improve to < 3 immediately after surgery required further reductions of 2-11 points to reach satisfaction.

Conclusions: The MCID thresholds from this study provide crucial benchmarks for assessing dysphagia changes after anterior cervical surgery, allowing tailored interventions. Patients with baseline dysphagia are less likely to experience early dissatisfaction, and high peak scores negatively impact long-term satisfaction. These findings emphasize the importance of proactive dysphagia management to enhance patient outcomes.