To Örebro University

BACKGROUND AND OBJECTIVES: Surgical decompression is commonly required to relieve symptoms of cervical radiculopathy and allow for functional recovery. There are only a handful of studies analyzing return-to-work (RTW) outcomes after cervical spine surgery for cervical radiculopathy. This study seeks to elucidate RTW outcomes and to identify predictors preventing RTW in patients surgically treated for cervical radiculopathy in a Swedish nationwide prospective registry.

METHODS: A nationwide cohort analysis was conducted using prospectively gathered data from the Swedish Spine Registry. All patients with documented postoperative outcomes focusing on 1-year RTW rates were included. To identify predictive factors influencing RTW at 1 year postoperatively, separate univariable and multivariable logistic regression models were developed, incorporating demographic, functional and clinical, as well as preoperative and postoperative data, and occupational characteristics.

RESULTS: A total of 3929 patients were included with an average age of 49.5 years, with most patients working in moderate- or high-intensity jobs and nearly half on sick leave before surgery. Most surgeries were elective, and an anterior approach was preferred. At the 1-year mark after surgery, 85% of patients had returned to work, with full-time RTW reaching 67% and part-time RTW 18%. In this cohort, 15% had not returned to work at all. Higher age, previous cervical spine surgery, high job intensity, preoperative full-time sick leave and full-time sickness benefits, longer preoperative arm pain durations as well as higher preoperative Neck Disability Index, and lower EuroQOL 5 dimensions scores were independently associated with a reduced likelihood of RTW at 1 year postoperatively.

CONCLUSION: Eighty-five percent of the patients surgically treated for radiculopathy RTW within 1 year. Higher age, jobs with greater physical demands, longer duration of arm pain, higher preoperative neck disability index and lower EuroQOL 5 dimensions scores, as well as being on full-time sick leave, were all linked to a reduced chance of RTW.

INTRODUCTION: Peripheral nerve sheath tumors are the most common tumor of the peripheral nerves. In general, surgery has a favorable outcome and is the treatment of choice. However, postoperative neurologic deficits are not uncommon, and predictors of outcome are poorly defined.

OBJECTIVE: To evaluate clinical outcomes after surgical treatment of benign peripheral nerve sheath tumors and identify outcome predictors that may affect preoperative decision making and improve surgical outcomes.

METHOD: In this single center retrospective study, all patients surgically treated for a benign peripheral nerve sheath tumor between 2005 and 2020 were eligible for inclusion. Medical records and imaging data were reviewed. Studied outcomes were changes in neurological symptoms, pain, and tumor recurrence. Logistic regression was performed to identify possible outcome predictors.

RESULTS: In total, 81 patients undergoing 85 separate surgeries for benign peripheral nerve sheath tumors were included. The most common preoperative symptoms were local pain (90%) followed by a noticeable mass (78%), radiating pain (72%), sensory deficit (18%) and motor deficit (16%). A postoperative improvement of symptoms was seen in 94% of those with pain, 48% of those with sensory deficits and 78% of those with motor deficits. However, 35% and 9% developed new postoperative sensory and motor deficits, respectively. Multivariable analysis showed complete tumor removal as a predictor of reduced pain (p = 0.033), and younger age and larger tumors were risk factors for persistent or increased sensory deficits (p = 0.002 and p = 0.005, respectively). There were no significant predictors of motor deficits. Neurocutaneous syndromes were associated with increased odds of tumor recurrence on univariable analysis (p = 0.008).

CONCLUSION: Surgery of benign peripheral nerve sheath tumors is a safe procedure with a favorable outcome in most cases. Younger age and larger tumors were risk factors for persistent or increased sensory deficits, while complete tumor removal was associated with reduced pain. Patients with neurocutaneous syndromes had a higher rate of tumor recurrence. To further evaluate outcome predictors, we recommend future studies to focus on longer follow-up periods to assess the natural course of postoperative neurological deficits.

PURPOSE: The decision to cross the cervicothoracic junction (CTJ) during multilevel posterior cervical fusion remains controversial. While constructs extending into the thoracic spine may enhance stability, they may also increase surgical complexity. The clinical relevance of these differences, particularly regarding patient-reported outcomes (PROMs), is still unclear. We hence aimed to determine whether extending fusion across the CTJ impacts PROMs and perioperative complication rates in a nationwide cohort.

METHODS: This retrospective cohort study used prospectively collected data from the Swedish Spine Registry (Swespine). Adult patients who underwent multilevel posterior cervical fusion were divided into two groups: those ending at C7 and those extending beyond the CTJ. Baseline characteristics, surgical details, complication rates, and PROMs at 1- and 5-years were compared.

RESULTS: Baseline characteristics were similar between groups (p ≥ 0.5). Perioperative complication and reoperation rates did not differ significantly between groups (p ≥ 0.5). Similarly, at both one- and five-years of follow-up, PROMs, including pain scores, disability indices, and satisfaction, were comparable (p ≥ 0.5). However, a significant difference was observed in terms of fine motor recovery, with patients whose constructs crossed the CTJ demonstrating a greater degree of improvement (p = 0.009).

CONCLUSIONS: Crossing the CTJ in multilevel posterior cervical fusion does not significantly affect complication rates, reoperations, or most PROMs at one and five years. Surgical decisions should prioritize anatomical and clinical factors, rather than expected differences in PROMs.

INTRODUCTION: Chiari malformation type 1 (CM1) is a common congenital disorder affecting both children and adults. Although pediatric and adult CM1 patients share many characteristics, the differences between the groups are not fully described.

METHOD: A comparative analysis was made of two previously defined cohorts of adult and pediatric non-syndromic CM1, surgically treated at the study center. Clinical outcomes were assessed using the Chicago Chiari outcome scale (CCOS) and radiological outcomes were measured as change in cerebellar tonsil and syringomyelia status.

RESULTS: A total of 209 patients (73 pediatric, 136 adults) were included, with median ages of 11 and 33 years, respectively. The proportion of female patients (62% vs 78%) was higher in the adult population (p = 0.012). Headache (p = 0.007), neck pain (p = 0.000), vertigo (p = 0.007), and sensory symptoms (p = 0.000) were more common in adults, while scoliosis (p = 0.000) and sleep apnea (p = 0.015) were more common in the pediatric population. Preoperative imaging findings did not differ significantly. After posterior fossa decompression, both groups scored a median CCOS of 15 at early follow-up (3 vs 4 months), though the pediatric population had a more favorable distribution of CCOS scores (p = 0.003). Postoperatively, syringomyelia status did not differ significantly between groups, but cerebellar tonsil status improved more frequently in adults (64% vs 88%, p = 0.000).

CONCLUSION: This study demonstrates that while headache is the most common presenting symptom in both pediatric and adult CM1 patients, pediatric patients are more likely to present with scoliosis and sleep apnea. In contrast adult patients more frequently experience headache, neck pain, vertigo, and sensory symptoms. There were no differences in other preoperative imaging variables and outcomes were favorable for most patients in both groups.

OBJECTIVE: To evaluate if intraoperative cone-beam CT (CBCT) provides equivalent image quality to postoperative multidetector CT (MDCT) in spine surgery, potentially eliminating unnecessary imaging and cumulative radiation exposure.

METHODS: Twenty-seven patients (16 men, 11 women; median age 39 years) treated with spinal fixation surgery were evaluated using intraoperative CBCT and postoperative MDCT. The images were independently evaluated by four neuroradiologists, utilizing a five-step Likert scale and visual grading characteristics (VGC) analysis. The area under the VGC curve (AUCVGC) quantified preferences between modalities. Intra- and inter-observer variability was evaluated using intraclass correlation coefficients (ICC). Image quality was objectively evaluated by contrast and signal-to-noise measurements (CNR, SNR).

RESULTS: In image quality, CBCT was the preferred modality in thoracolumbar spine (AUCVGC = 0.58, p < 0.001). Conversely, MDCT was preferred in cervical spine (AUCVGC = 0.38, p < 0.004). The agreement was good for inter-observer and moderate in intra-observer (ICC 0.76-0.77 vs 0.60-0.71), p < 0.001. SNR and CNR were comparable in thoracolumbar imaging, while MDCT provided superior and more consistent image quality in the cervical spine, p < 0.001.

CONCLUSION: In spine surgery, CBCT provides superior image quality for thoracolumbar imaging, while MDCT performs better for cervical imaging. Intraoperative CBCT could potentially replace postoperative MDCT in thoracolumbar spine procedures, while postoperative MDCT remains essential for cervical spine assessment.

KEY POINTS: Subjective assessment demonstrated that CBCT was the preferred modality for thoracolumbar spine imaging, while MDCT was favored for cervical spine imaging. Agreement between readers was good, while individual readings showed moderate consistency in repeated assessments. Objective assessment of image clarity and detail showed both modalities performed equally well in the thoracolumbar spine, while MDCT performed better in the cervical spine. Intraoperative CBCT proves superior to postoperative MDCT for thoracolumbar spine imaging, potentially eliminating redundant scans, and improving workflow. Postoperative MDCT remains essential for cervical spine procedures.

OBJECTIVE: Gross total resection is strived for in intramedullary spinal cord lesion surgery. Intraoperative neurophysiological monitoring (IONM) is the gold standard, but there is no consensus on the optimal IONM workflow. This study details our institutional workflow.

METHODS: We retrospectively reviewed all adults who underwent intramedullary resection at Karolinska University Hospital, 2007-2021 (n = 70). Continuous multimodal IONM (somatosensory-evoked potentials (SSEP), motor-evoked potentials (MEP) and epidural D-waves) was conducted by an in-room neurophysiologist. Alarm thresholds were preset (≥ 50% SSEP amplitude drop/10% latency rise; ≥ 80% MEP reduction; ≥ 50% D-wave loss) and triggered a standardized four-step rescue protocol (halt manipulation, raise MAP to 80-90 mm Hg, topical papaverine, observation). Motor/sensory function, modified McCormick (mMC) grade, pain, and sphincter control were documented pre-operatively, at 3 months, and ≥ 12 months.

RESULTS: Seventy patients were included. Most harboured ependymoma (51%), hemangioblastoma (18%) and cavernoma (8.5%). A neurophysiologist was present during every procedure. A ≥ 50% intra-operative SSEP-amplitude decrease was not followed by a sensory deficit (OR:3.0, 95% CI 0.86-10.6; p = 0.085) or mMC deterioration (OR:1.6, 0.33-7.5; p = 0.57) at either short- or long-term follow-up. In contrast, complete SSEP loss markedly increased the risk of postoperative sensory deficit (3-months-OR:25.2, 4.7-135; p < 0.001; long-term-OR 11.0, 2.8-43.8; p < 0.001) and poorer mMC grade (3-months-OR:7.8, 2.0-31; p = 0.004; long-term-OR:11.0, 2.8-43.8; p < 0.001). Loss of MEPs predicted a decline in mMC at long-term follow-up (OR:4.0, 1.06-15.1; p = 0.041).

CONCLUSIONS: Live data from continuous intraoperative neurophysiological monitoring, expertly interpreted in the OR, could potentially be used to make surgical and anesthesiologic adjustments with the goal of minimizing the risk of negative neurological outcomes. Significant associations were found between decreased or lost IONM signals and poorer sensorimotor function and mMC score at short- and long-term follow-up. Implementation of the IONM workflow is suggested in all intramedullary surgery.

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 one month after surgery. Predictive performance was assessed using discrimination and calibration metrics.

METHODS: Patients with missing dysphonia data at the one-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, EQ5Dindex, 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 one month after surgery.

PURPOSE: Patient involvement and shared decision-making (SDM) are central to patient-centered care and have been linked to improved patient satisfaction and outcomes. However, their implementation in spinal surgery remains limited, and the effect of patient involvement on postoperative outcomes is not well described.

METHODS: This observational cohort study used data from the Swedish Spine Registry (Swespine) to examine the association between perceived patient involvement in decision-making and postoperative outcomes among adults undergoing cervical spinal surgery between 2006 and 2020. Propensity score-matching was performed at a ratio of 2:1 to minimize baseline differences between groups. Uni- and multivariable analyses were conducted to identify factors associated with patient's perception of involvement in decision-making.

RESULTS: A total of 3,249 patients were included, with 81% (n = 2,640) reporting perceived involvement in decision-making and 19% (n = 609) not. Following matching, patients who were involved in decision-making had significantly greater improvements at one year follow-up regarding neck and arm pain (p < 0.001), disability (p < 0.001), health-related quality of life (p < 0.001), and subjective satisfaction (p < 0.001). Patients with poorer preoperative health status are more likely to feel involved in decision making, while those undergoing minor procedures feel significantly less involved. Positive predictors of perceived patient involvement included number of operated levels (OR 1.13, p = 0.041), unemployment (OR 1.89, p < 0.001), walking less than 100 m at a normal pace (OR 1.45, p = 0.044), and higher preoperative NDI (OR 1.01, p = 0.039). Negative predictors included higher preoperative EQ-5D index (OR 0.64, p = 0.022) and higher preoperative myelopathy score (OR 0.96, p = 0.042).

CONCLUSION: Patients with a higher degree of perceived involvement report better postoperative patient-reported outcomes following cervical spinal surgery. Patients undergoing larger surgeries and with poorer preoperative health status were more likely to perceive involvement than those undergoing minor procedures. Identifying and supporting patients that are susceptible to feel less involved in treatment-related decisions through individualized information or counseling may help optimize outcomes and satisfaction.