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Background and purpose: Degenerative cervical myelopathy (DCM) is the most common cause of spinal cord dysfunction in adults. Repeated follow-ups after surgery are resource consuming. The aim was to examine whether patient-reported outcome measures (PROMs) change after the first year. The purpose of this study was to investigate whether it is necessary to obtain follow-up data from patients more than 1 year after surgery for DCM.

Methods: We included individuals treated surgically for DCM in the Swedish Spine registry (Swespine), with available preoperative, 1-, and 2-year PROMs, primarily the European Myelopathy Scale (EMS) and secondarily the Neck Disability Index (NDI), and the European Quality of life Visual Analogue Scale (EQ-VAS). A tertiary analysis included available 5-year data. Median, interquartile range (IQR), and Bland-Altman plots were used to compare PROM data at different follow-up time points.

Results: 642 individuals had baseline, 1-, and 2-year follow-up data, of whom 347 also had 5-year data. EMS was 14 (12-16) preoperative, 15 (12-17) at the 1-year follow-up, and 15 (12-17) at the 2-year follow-up. Corresponding data for NDI was 38 (24-50), 25 (12-42), and 26 (12-42) and for EQ-VAS 50 (30-60), 60 (42-77), and 60 (40-75). Similar findings were seen in individuals who also had 5-year data. Bland-Altman plots indicated good agreement between 1and 2-year data, and between 1and 5-year data and were without proportional bias.

Conclusion: In individuals treated for DCM no clinically meaningful change in PROMs occurred after the 1-year follow-up.

BACKGROUND CONTEXT:

Anterior Cervical Discectomy and Fusion (ACDF) is a surgical technique that can be used to treat several conditions of the cervical spine. Small sized studies have reported differences in radiological findings between cage only and cage with plate fusion techniques but no differences in clinical outcome, hence, larger studies are needed. PURPOSE: The aim of this study was to compare the outcomes of ACDF between cage only and cage with plate fixation.

STUDY DESIGN:

Retrospective study design on prospectively collected registry data.

PATIENT SAMPLE:

Individuals treated for cervical degenerative radiculopathy, with ACDF using either cage only or cage with plate fixation were identified in the Swedish Spine registry (Swespine). Included individuals had available baseline and 1-year postoperative data for the Numeric Rating Scale (NRS) for neck and arm pain. OUTCOME MEASURES: Patient reported outcome measures (PROMs) included were NRS for neck and arm pain, Neck Disability Index (NDI), and EuroQol-Visual Analogue Scale (EQ-VAS). Complications reported by clinicians and patients were also available in the Swespine registry, as well as the degree of satisfaction at the 1-year follow-up.

METHODS:

Outcomes at the 1-year follow-up were compared between the cage only or cage with plate groups. In a secondary analysis, one or two levels of surgery was compared between the groups. The number of patients that reached the Minimum Clinically Important Difference (MCID) in improvement after treatment was calculated and compared between the groups. The Mann Whitney-U test was used for continuous variables and the Chi2 test for categorical variables.

RESULTS:

The groups included 344 individuals instrumented with cage only, and 334 receiving cage with plate fixation. NDI improvement was -14.0 points (95% CI: -12.2-[-15.8]) in the cage only group and -17.9 points (95% CI: -16.1 - [-19.8]) points in the cage with plate group (p=.007). A lower rate of hoarseness postoperatively was reported by the cage only group (OR: 0.65 [0.450.93], p=.026). No differences were seen in other outcomes.

CONCLUSION:

Clinical improvement was seen in both groups, but the improvement of NDI was better in the cage with plate group and the rate of hoarseness was lower in the cage only group.

BACKGROUND: Dysphonia is one of the more common complications following anterior cervical discectomy and fusion (ACDF). ACDF is the gold standard for treating degenerative cervical spine disorders, and identifying high-risk patients is therefore crucial. PURPOSE: This study aimed to evaluate different machine learning models to predict persistent dysphonia after ACDF.

STUDY DESIGN: A retrospective review of the nationwide Swedish spine registry (Swespine). PATIENT SAMPLE: All adults in the Swespine registry who underwent elective ACDF between 2006 and 2020.

OUTCOME MEASURES: The primary outcome was self-reported dysphonia lasting at least 1 month after surgery. Predictive performance was assessed using discrimination and calibration metrics.

METHODS: Patients with missing dysphonia data at the 1-year follow-up were excluded. Data preprocessing involved one-hot encoding categorical variables, scaling continuous variables, and imputing missing values. Four machine learning models (logistic regression, random forest (RF), gradient boosting, K-nearest neighbor) were employed. The models were trained and tested using an 80:20 data split and 5-fold cross-validation, with performance metrics guiding the selection of the best model for predicting persistent dysphonia.

RESULTS: In total, 2,708 were included in the study. Twelve key predictors were identified. Four machine learning models were tested, with the RF model achieving the best performance (AUC=0.794). The most significant predictors across models included preoperative NDI, EQ5Din- dex, preoperative neurology, number of operated levels, and use of a fusion cage. The RF model, chosen for its superior performance, showed high sensitivity and consistent accuracy, but a low specificity and positive predictive value.

CONCLUSIONS: In this study, machine learning models were employed to identify predictors of persistent dysphonia following ACDF. Among the models tested, the RF classifier demonstrated superior performance, with an AUC value of 0.790. The RF model identified NDI, EQ5Dindex, and number of fused vertebrae as key variables. These findings underscore the potential of machine learning models in identifying patients at increased risk for dysphonia persisting for more than 1 month after surgery. (c) 2024 The Author(s). Published by Elsevier Inc. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/)

Introduction: 

Back pain is common in idiopathic scoliosis. The aim of this study was to study known genetic variants associated with pain in individuals with idiopathic scoliosis.

Methods: 

We included 1442 individuals with juvenile or adolescent idiopathic scoliosis from Sweden and Denmark. Single nucleotide variants (SNV) genotyping was performed on 37 SNVs. Pain was assessed using 2 questionnaires. The mean pain domain score on the Scoliosis Research Society 22 revised questionnaire (SRS-22r) ranging between 1 (worst) and 5 (best) was dichotomized into a “back pain group” (score <4) and a “no back pain group” (score ≥4). The EuroQol 5-dimensions (EQ-5D) 3 level pain domain was dichotomized into a “no pain group” and a “pain group.” Odds ratios were used to describe the associations.

Results: 

Based on the SRS-22r pain domain scores, 456 individuals (32%) reported back pain. Based on the EQ-5D questionnaire, 813 individuals (56%) reported moderate or extreme pain/discomfort. The odds ratio for the associations between the selected genetic variants and back pain or pain in general as measured with SRS-22r and EQ-5D-3L ranged between 0.88 to 1.17 and 0.86 to 1.16, with P-values ranging between 0.08 to 0.99 and 0.08 to 0.95.

Conclusion: 

This study suggests that known genetic variants associated with pain do not play a significant role in the development of pain in individuals with idiopathic scoliosis.

Background and purpose

Although navigation is increasingly used in spinal surgery, the advantage of different navigation technologies is still a matter of debate. Conventional image-guided navigation is currently the gold standard. However, modern, Augmented reality-based navigation methods are increasingly gaining ground. Surgical navigation in deformity surgery allows placement of pedicle screws in small and deformed pedicles and may result in both a higher accuracy and density of pedicle screw placement. The aim of this trial is to compare AR and conventional surgical navigation to free-hand technique.

Patients and methods

This is a single center, open label, parallel assignment, three arm, randomized, controlled trial, comparing: Augmented reality surgical navigation (ARSN), Infrared surgical navigation (IRSN) and Free-hand (FH) technique. Individuals scheduled for spinal deformity surgery are eligible for inclusion. The inclusion criteria are written informed consent, age ≥ 12 years and spinal deformity. Subjects will be randomized intraoperatively and strictly sequentially.

Outcomes

The primary endpoint is accurately placed pedicle screws based on intraoperative verification cone beam computed tomography (CBCT) scan. All radiological image analyses, on both intra- and postoperative imaging will be performed postoperatively by blinded reviewers.

Several secondary outcome measures including revision rate, radiation exposure, implant density and final accuracy will be analyzed. Patient reported outcomes will also be assessed. Finally, a cost–benefit analysis will be performed.

Start of trial and estimated duration

The SPINAV trial started recruiting patients in January 2022 and will continue for approximately 2.5 years.

Trial registration

The trial is registered at clinicaltrials.gov (NCT05107310) on 2021–11-03.

BACKGROUND AND OBJECTIVES:Vertebral artery injury (VAI) because of traumatic subaxial cervical spine injury is a rare but potentially devastating condition as it could lead to stroke. The aim of this study was to examine the incidence, risk factors, outcomes, and radiographic predictors of VAI in patients surgically treated for subaxial cervical spine injuries at a tertiary care trauma center.

METHODS:This is a retrospective population-based cohort study, including all patients surgically treated for traumatic subaxial cervical spine injuries at the study center between 2006 and 2018. Primary outcomes included mortality and morbidity after the injury. Propensity score matching, survival, univariable, and multivariable analyses were used to study the outcomes of interest.

RESULTS:Traumatic VAI primarily occurred after high-energy traumas such as motor vehicle accidents and falls from heights. The median age was 64.4 years (47.4-69.1), and 69% were male. In the cohort of patients with subaxial cervical injury, 54% had a spinal cord injury (SCI). In the subgroup with VAI, the frequency of SCI was 66% and a concomitant SCI and VAI were associated with a more severe American Spinal Cord Injury Association Impairment Scale grade (P = .015). However, after accounting for age, sex, and associated injuries, VAI did not affect postoperative complications, short- or long-term outcomes, or mortality rates. Facet joint dislocation was a unique radiographic predictor of VAI (odds ratio 3.8 [CI 1.42-10.7], P = .009).

CONCLUSION:The findings suggest that clinical outcomes of patients with traumatic cervical spine injuries were not negatively affected by the presence of a VAI. Several radiographic factors were associated with VAI; however, only facet joint dislocation remained as an independent predictor of this injury.

Objective

To explore secondary outcomes at endpoint comparing treatments with adequate self-mediated physical activity combined with either night-time brace (NB), scoliosis-specific exercise (SSE), or adequate self-mediated physical activity alone (PA) in Adolescent Idiopathic Scoliosis (AIS).

Methods

A longitudinal, prospective, multicenter RCT was conducted including 135 girls/boys, Cobb angle 25–40°, 9–17 years, and ≥1-year remaining growth were randomly allocated into NB, SSE, or PA group. Endpoint was curve progression of ≤6° (success) at skeletal maturity or >6° (failure). Outcomes included angle of trunk rotation (ATR), major curve Cobb angle, Spinal Appearance Questionnaire (pSAQ), Scoliosis Research Society-22r (SRS-22r), EQ-5Dimensions Youth 3Levels (EQ-5D-Y-3L), and EQ-Visual-Analogue-Scale (EQ-VAS), adherence to treatment and International Physical Activity Questionnaire (IPAQ-SF).

Results

At endpoint, 122 patients were analyzed per protocol, mean age 12.7 (±1.4) years, and mean Cobb angle 31° (±4.3). A significant difference in change for ATR favored NB group compared to SSE group -2.0º (95% CI -3.7 to -0.3). EQ-5D-Y-3L dimensions showed a significant difference in change with decrease in mobility (p=0.031), and usual activities (p=0.003) for SSE compared to NB and PA groups. Treatment adherence was adequate but slightly better in NB and PA groups compared to SSE on self-report (p=0.012), and health care provider (HCP) report was better in PA compared to SSE group (p=0.013). Higher motivation and capability explained 53% of the variability and gave better odds for higher adherence (OR = 11.12, 95% CI = 1.5 to 34.4; OR = 7.23, 95% CI = 2.9 to 43.3), respectively.

Conclusions

Night-time brace, scoliosis-specific exercise or physical activity interventions for adolescents with idiopathic scoliosis showed small differences between groups in trunk rotation, spinal deformity and appearance, health-related quality of life, and treatment adherence but not likely reaching clinical relevance.

Background and purpose - Pain in the sacroiliac joint may be caused by abnormal joint motion. Diagnosis is mainly based on clinical tests. The aims of this study were to examine whether low-dose computed tomography with provocation of the hip could detect sacroiliac joint motion , to study whether provocation of the hip results in greater sacroiliac joint motion in the ipsilateral than in the contralateral sacroiliac joint.

Patients and methods - 12 patients with sacroiliac joint pain were examined with low-dose computed tomography scans of the sacroiliac joint, one with the hips in the neutral position, and one each in provocation with the left or the right hip in a figure-of-4 position. Accuracy was tested by comparing internal rotation of the sacrum with internal rotation in the sacroiliac joint. Motion in the sacroiliac joint was assessed by comparing the position of each of the ilia with the reference, the sacrum. Data is shown as mean with 95% confidence interval (CI).

Results - We observed greater motion in the sacroiliac joint than internally in the sacrum, i.e., 0.57(degrees) (CI 0.43-0.71) vs. 0.20(degrees) (CI 0.11-0.28). The motion of the geometric center of the moving object for the sacroiliac joint was larger on the provoked side; mean difference 0.17 mm (CI 0.01-0.33), P = 0.04. Corresponding figures for rotation were mean difference 0.19(degrees) (CI 0.10-0.28), P < 0.001. Compared with the sacrum, the largest motion was seen at the anterior superior iliac spine; mean difference 0.38 mm (CI 0.10-0.66), P = 0.001.

Conclusion - Provocation in the figure-of-4 position of the hip results in sacroiliac joint motion measurable with computed tomography motion analysis. Provocation of the hip induces larger motion on the ipsilateral than on the contralateral sacroiliac joint.

Adolescent idiopathic scoliosis (AIS) is a common and progressive spinal deformity in children that exhibits striking sexual dimorphism, with girls at more than fivefold greater risk of severe disease compared to boys. Despite its medical impact, the molecular mechanisms that drive AIS are largely unknown. We previously defined a female-specific AIS genetic risk locus in an enhancer near the PAX1 gene. Here, we sought to define the roles of PAX1 and newly identified AIS-associated genes in the developmental mechanism of AIS. In a genetic study of 10,519 individuals with AIS and 93,238 unaffected controls, significant association was identified with a variant in COL11A1 encoding collagen (α1) XI (rs3753841; NM_080629.2_c.4004C>T; p.(Pro1335Leu); p=7.07E^–11, OR = 1.118). Using CRISPR mutagenesis we generated Pax1 knockout mice (Pax1^-/-). In postnatal spines we found that PAX1 and collagen (α1) XI protein both localize within the intervertebral disc-vertebral junction region encompassing the growth plate, with less collagen (α1) XI detected in Pax1^-/- spines compared to wild-type. By genetic targeting we found that wild-type Col11a1 expression in costal chondrocytes suppresses expression of Pax1 and of Mmp3, encoding the matrix metalloproteinase 3 enzyme implicated in matrix remodeling. However, the latter suppression was abrogated in the presence of the AIS-associated COL11A1^P1335L mutant. Further, we found that either knockdown of the estrogen receptor gene Esr2 or tamoxifen treatment significantly altered Col11a1 and Mmp3 expression in chondrocytes. We propose a new molecular model of AIS pathogenesis wherein genetic variation and estrogen signaling increase disease susceptibility by altering a PAX1-COL11a1-MMP3 signaling axis in spinal chondrocytes.