Spine最新文献

Study design: Prospective cohort study.

Objective: To identify patient factors that predict changes in adjacent segment kinematics three years after ACDF.

Summary of background data: Approximately 25% of patients who undergo anterior cervical discectomy and fusion (ACDF) develop symptomatic adjacent segment disease (ASD) requiring reoperation within 10 years. Studies have found associations between ASD and patient genetics, age, BMI, psychiatric history, and preoperative disc degeneration. Few studies have linked these factors to mechanical changes to explain ASD.

Methods: Patients performed flexion/extension and axial rotation captured by biplane radiography before, one year after, and three years after ACDF (3YR-POST). Digitally reconstructed cervical radiographs were matched to the biplane radiographs to calculate intervertebral kinematics and preoperative disc height. Patient age, sex, BMI, smoking, diabetes, psychiatric history, inciting event, length of symptoms, preoperative disc bulge, and NDI were collected. Multivariate linear regression identified patient factors associated with changes in adjacent segment kinematics and NDI 3YR-POST.

Results: 62 patients completed testing. Younger age (1.1° per 10 years, 95% CI [0.04, 1.8], P=0.011), female sex (1.8°, 95% CI [0.5, 3.1], P=0.016), lower BMI (1.4° per 10 kg/m², 95% CI [0.4, 2.5], P=0.019), and no superior adjacent disc bulge (1.4°, 95% CI [0.0, 2.7], P=0.035) predicted larger increase in superior adjacent segment flexion/extension range of motion (ROM) 3YR-POST. Lack of superior adjacent disc bulge (1.2°, 95% CI [0.2, 2.2], P=0.025) predicted larger increase in superior adjacent segment axial rotation ROM. No patient factors were associated with changes in inferior adjacent segment ROM.

Conclusion: Greater increase in superior adjacent segment motion 3YR-POST is predicted in younger, lower BMI, female patients with healthier preoperative discs. These results support the theory that disc degeneration progresses from early instability in younger, healthier discs to stabilization in older, less healthy discs.

Study design/setting: Retrospective study at a single academic tertiary care center.

Objective: To evaluate osseous and vascular structures at C1 on preoperative MRIs and CTAs.

Background data: No prior studies have compared the diagnostic accuracy between magnetic resonance imaging (MRI) and computed tomography angiography (CTA) to assess C1 and internal carotid artery (ICA) anatomy prior to surgical instrumentation.

Methods: We retrospectively reviewed adult patients who underwent both cervical spine CTA and MRI between 2007 and 2018. Patients with prior cervical surgery or MRIs not extending to the atlas were excluded. Ten standardized osseous and vascular measurements were performed on both modalities using anatomical landmarks at C1. Paired t-tests and intraclass correlation coefficients (ICCs) assessed differences and agreement. A sub-analysis normalized measurements to anterior-posterior C1 length to account for potential modality-based scaling differences.

Results: Of 209 patients reviewed, 119 met inclusion criteria (mean age 65.1 years; 56% female). The agreement between CTA and MRI across 10 anatomical measurements was low, with ICCs ranging from 0.006 to 0.427. All measurements except the distance from the end of the ideal screw trajectory to the anterior plane of C1 demonstrated statistically significant differences between CTA and MRI (P<0.05). After standardizing values to anterior-posterior C1 length, ICCs for the nine measurements remained low (0.012 to 0.305), with only standardized measurements, distance from the end of the ideal screw trajectory to the anterior plane of C1 and the distance from the origin of the ideal screw trajectory to the ICA showing no statistically significant differences.

Conclusions: This study evaluated the accuracy of preoperative CTA and MRI in assessing C1 and ICA anatomy for atlantoaxial fusion planning, revealing variability in measurement agreement between the two. The findings highlight the need to tailor imaging choices to each clinical scenario, balancing diagnostic value, radiation exposure and surgical risk.

Study design: Retrospective cohort study of patients undergoing single-level L5-S1 anterior or transforaminal lumbar interbody fusion between 2012 and 2024 at a single academic institution, with preoperative and one-year postoperative radiographic assessment of sagittal alignment parameters.

Objective: To quantify changes in lumbar pelvic angle (LPA), pelvic tilt (PT), global lumbar lordosis (L1-S1), regional lumbar lordosis (L4-S1), and segmental lumbar lordosis (L5-S1) among single-level L5-S1 ALIF and TLIF patients.

Summary of background data: Restoration of sagittal alignment is a primary goal of lumbar fusion. While ALIF is regarded as superior to TLIF in restoring segmental lordosis, its effect on global and regional alignment remains uncertain, and few studies directly compare their impact on spinopelvic parameters.

Methods: The electronic medical record was queried for patients who underwent single-level L5-S1 ALIF or TLIF with preoperative and one-year postoperative imaging. Sagittal parameters were measured using Surgimap software. Group comparisons were assessed with unpaired t-tests or Wilcoxon signed-rank tests.

Results: Radiographic measurements were available for 174 patients (ALIF n=73, TLIF n=101). ALIF patients had significantly greater improvement in L4-S1 (+4.2° vs. -1.1°, P=0.002) and L5-S1 lordosis (+4.6° vs. -4.8°, P<0.001). No significant differences were observed in postoperative changes for L1-S1 lordosis (+2.2° vs. -1.4°, P=0.250), LPA (-1.9° vs. -1.4°, P=0.743), or PT (-0.9° vs. +0.4°, P=0.093). Permutation testing confirmed that the observed difference in LPA improvement between cohorts (-0.51°) was not statistically significant (P=0.673), and post hoc analysis confirmed adequate power to detect a difference of 3.37°. Sensitivity analyses using ANCOVA, adjusting for baseline radiographic values and covariates, were concordant.

Conclusion: ALIF provided superior regional and segmental lordosis but did not improve global alignment compared with TLIF. This study is the first to quantify the effect of ALIF versus TLIF on LPA, highlighting the limited impact of single-level fusion on global spinopelvic alignment.

Study design: Experimental animal study using a rabbit model of chronic cervical spinal cord compression.

Objective: To investigate the relationship between MRI T2-weighted signal intensity changes in the spinal cord and underlying apoptotic and neuroinflammatory mechanisms in chronic cervical spinal cord compression.

Summary of background data: T2-weighted MRI hyperintensity in degenerative cervical myelopathy (DCM) patients is commonly observed, but its pathological significance remains incompletely understood. Apoptosis and neuroinflammation are key pathophysiological mechanisms, yet their correlation with MRI signal changes lacks systematic investigation.

Methods: Twenty-four rabbits were randomized into control, mild compression, and severe compression groups (n=8/group). Chronic cervical spinal cord compression was induced at C3 using radiopaque resin pins. Motor function (Tarlov scores, Rivlin inclined plane test), somatosensory evoked potentials (SEPs), and MRI signal intensity ratios (SCR) were assessed at 1 week, 3 months, and 6 months. At 6 months, spinal cord tissues were analyzed via hematoxylin-eosin staining, TUNEL assay, immunofluorescence, and Western blotting for apoptotic (Bax, Bcl-2, Caspase-3) and neuroinflammatory markers (NLRP3, ASC, NF-κB).

Results: Compression severity correlated with functional decline and prolonged SEP latency (P<0.05). At 6 months, SCR was significantly elevated in severe compression group (1.16 vs. 1.00 in controls, P<0.001). TUNEL-positive cells increased proportionally with compression severity (3.2±0.8% control vs. 19.8±2.4% severe compression, P<0.001). Bax/Bcl-2 ratio and NLRP3 expression escalated with compression intensity. Spearman analysis revealed strong positive correlations between SCR and both Bax/Bcl-2 ratio (rs=0.817, P<0.001) and NLRP3 expression (rs=0.849, P<0.001).

Conclusions: In chronic cervical spinal cord compression, MRI T2 hyperintensity correlates significantly with the severity of neuronal apoptosis and NLRP3-mediated neuroinflammation, suggesting that SCR may serve as a quantitative imaging biomarker for underlying pathological changes in DCM.

Study design: Survey-based, prospective study.

Objective: To establish a baseline range of SRS-22r, analyzing the impact of age and sex within the American population.

Summary of background data: The Scoliosis Research Society-22r (SRS-22r) is a widely used PROM for evaluating satisfaction and quality of life in adult spinal deformity. However, normative age-stratified data, especially for adults over 80, remain limited. Establishing population-based SRS-22r values is essential for contextualizing outcomes and guiding treatment strategies.

Methods: A total of 658 participants were recruited in January 2025 through the Connect platform (CloudResearch) to complete a RedCap survey containing six demographic questions and the full SRS-22r. We targeted about 100 participants per decade and grouped them into four age cohorts: 18-39, 40-59, 60-79, and 80-89 years. Racial targets reflected U.S. Census distributions.

Results: Of 658 participants, 599 remained after exclusions for prior surgery and incomplete data. Of these, 301 (50.2%) were female with a mean BMI of 26.7±6.2. The mean SRS-22r Total score was 3.9±0.7, with domain scores of Function 4.1±0.8, Pain 3.9±0.8, Self-Image 3.7±0.8, and Mental Health 3.7±0.9. ANOVA showed a U-shaped age effect, with the 18-39 and 80+ groups reporting higher scores across most domains (P<.01). Females had lower scores on all domains (P<.01). BMI correlated negatively with Total (r=-0.24), Self-Image (r=-0.34), and Function (r=-0.23) (all P<.001).

Conclusion: Baseline SRS-22r scores in U.S. adults are strongly shaped by age, sex, and BMI. Scores follow a clear U-shaped pattern, with the youngest and oldest adults reporting the best health, while higher BMI and female sex consistently predict lower scores. These benchmarks provide essential context for interpreting SRS-22r scores in adult spinal deformity.

Study design: Retrospective cohort study.

Objectives: In adult spinal deformity (ASD) surgery patients, we sought to:1)report preoperative/postoperative lordosis apex, number-of-vertebrae in lower/upper lordosis arc, and inflection point, and 2)determine their impact on postoperative outcomes.

Summary of backgrounds data: Impact of lordosis apex, arcs, and inflection point on postoperative outcomes remains unclear.

Methods: ASD patients (2009-2021) with ≥5-level fusion, sagittal/coronal deformity, and ≥2-year follow-up was analyzed. Primary exposures were pre/postoperative lordosis apex, vertebrae in upper/lower arcs, and inflection point. Outcomes included mechanical complications, reoperations, patient-reported outcome measures, and postoperative alignment. Multivariable regression controlled for age, body mass index (BMI), and comorbidities.

Results: Among 202 patients (mean age:64.4±16.7 y,77.2% females): Lordosis Apex: Most common preoperative apex was L5(32.7%), followed by L4(20.3%). Postoperatively, 125(61.9%) had an apex change-89(71%) cranially-directed and 36(29%) caudally-directed. Cranially shifts led to 6.3±14.1° decrease in L4-S1 lordosis, caudal change showed 3.7±13.9° increase(P=0.002). Lordosis Arcs: Mean vertebrae in lower and upper lordotic arcs were 1.4±1.0 and 2.6±1.1, which postoperatively increased by 0.2±0.8 and 0.5±1.5(P=0.043), respectively. Greater increase in upper-arc vertebrae correlated with higher 2-year numeric rating scale (NRS)-back pain (ρ=0.020,P=0.030;β=0.40, 95%CI:0.03-0.78,P=0.036). Inflection Point: Preoperatively, 86(42.6%) patients had a T12/L1 inflection point, of which 72(83.7%) remained at T12/L1 postoperatively. Of 116(57.4%) patients with inflection point above/below T12/L1, 59(50.9%) transitioned to T12/L1 postoperatively. Preoperative inflection point above/below T12/L1 was linked to more spinopelvic complications (38.8% vs. 22.1%,P=0.012;OR=0.49, 95%CI:0.25-0.94,P=0.033). Postoperative T12/L1 inflection was associated with higher radiographic proximal junctional kyphosis (PJK) (56.0% vs. 40.8%,P=0.041;OR=1.96, 95%CI=1.03-3.72,P=0.040).

Conclusion: After ASD surgery, most patients showed a cranial lordotic apex shift, with greater increase in upper than lower arc vertebrae-highlighting the difficulty of restoring lordosis caudally. Cranial apex shift was associated with smaller L4-S1 lordosis and greater 2-year back pain, while a preoperative inflection point outside T12/L1 increased the risk of spinopelvic complications. Incorporation of Roussouly principles may help spine surgeons improve outcomes and mitigate complications.

Study design: Retrospective study.

Objective: To determine the prevalence of new chronic pain conditions within one-year of whiplash and factors associated with chronic pain following whiplash exposure.

Summary of background data: Whiplash is among the most common injuries that occur following motor vehicle accidents. Many have postulated that whiplash is a progenitor for the development of chronic pain. Prior research in this arena has been limited.

Methods: We retrospectively identified TRICARE beneficiaries who sustained a whiplash injury between 2017-2023. The records of eligible beneficiaries were abstracted to obtain age at the time of injury, race, sex, US census region, sponsor rank, mental health diagnoses, environment of care, beneficiary status, time-period of injury and number of co-morbidities. We considered junior enlisted sponsor rank indicative of lower socioeconomic strata. The primary outcome was development of a chronic pain condition. We used multivariable logistic regression with re-weighting to account for confounders. We examined interactions between sex/mental health conditions, sex/socio-economic status and sex/time-period to address secular trends.

Results: The development of new chronic pain conditions occurred in 23.4%. After adjusting for confounders, we found that women (OR 1.57, 95% CI 1.49, 1.65), pre-existing mental health conditions (OR 1.35; 95% CI 1.28, 1.42) and our proxy for lower socioeconomic status (OR 1.15; 95% CI 1.04, 1.27) were significantly associated with the likelihood of developing chronic pain disorders within 1-year of whiplash injury. There were interactions between women and mental health conditions, as well as women and socio-economic status.

Conclusions: This represents the largest study that longitudinally surveys for the development of chronic pain conditions following whiplash. The incidence of chronic pain after whiplash is lower than has been previously postulated. We believe these findings can inform management in the post-injury time-period and recommendations for surveillance.

Study design: Multi-center retrospective cohort study.

Objective: To investigate whether preoperative cervical extension range of motion (eROM) and flexion range of motion (fROM) predict postoperative kyphotic change and affect clinical outcomes after laminoplasty for degenerative cervical myelopathy (DCM).

Summary of background data: Cervical laminoplasty is a standard procedure for DCM; however, postoperative kyphotic change due to loss of cervical lordosis (CL) is a major concern. Although small eROM and large fROM may predict postoperative CL loss, their impact on clinical outcomes is unclear.

Methods: We analyzed 147 patients with DCM ≥60 years who underwent C3-C6 laminoplasty with ≥2 years of follow-up. Radiographic parameters (CL, eROM, and fROM) were measured pre- and postoperatively. Kyphotic change was defined as CL loss ≥10°. Clinical outcomes included Japanese Orthopaedic Association (JOA) score, visual analogue scale (VAS) for neck pain, EuroQol 5-dimension 5-level instrument (EQ-5D-5L), and Neck Disability Index (NDI). Logistic regression was used to identify predictors of kyphotic change, and clinical outcomes were compared between predictor-defined groups up to 2 years postoperatively.

Results: Kyphotic change occurred in 35 patients (23.8%) at 2 years postoperatively. Logistic regression revealed that small eROM (≤9°) and large fROM (≥37°) independently predicted postoperative kyphotic change at 1 and 2 years postoperatively. Its incidence in the small eROM and large fROM groups was significantly higher than that in their respective counterpart groups. No significant group differences were found in JOA score, VAS for neck pain, EQ-5D-5L, or NDI changes.

Conclusion: Preoperative small eROM and large fROM independently predicted postoperative kyphotic change after laminoplasty for DCM. However, these factors did not negatively affect neurological recovery, neck pain, quality of life, or cervical function for up to 2 years postoperatively. Laminoplasty remains an effective option for patients with DCM with eROM ≤9° or fROM ≥37°, despite potential CL loss.

Level of evidence: III.