Extended reality in cranial and spinal neurosurgery - a bibliometric analysis

PURPOSE

This bibliometric analysis of the top 100 cited articles on extended reality (XR) in neurosurgery aimed to reveal trends in this research field. Gender differences in authorship and global distribution of the most-cited articles were also addressed.

METHODS

A Web of Science electronic database search was conducted. The top 100 most-cited articles related to the scope of this review were retrieved and analyzed for trends in publications, journal characteristics, authorship, global distribution, study design, and focus areas. After a brief description of the top 100 publications, a comparative analysis between spinal and cranial publications was performed.

RESULTS

From 2005, there was a significant increase in spinal neurosurgery publications with a focus on pedicle screw placement. Most articles were original research studies, with an emphasis on augmented reality (AR). In cranial neurosurgery, there was no notable increase in publications. There was an increase in studies assessing both AR and virtual reality (VR) research, with a notable emphasis on VR compared to AR. Education, surgical skills assessment, and surgical planning were more common themes in cranial studies compared to spinal studies. Female authorship was notably low in both groups, with no significant increase over time. The USA and Canada contributed most of the publications in the research field.

CONCLUSIONS

Research regarding the use of XR in neurosurgery increased significantly from 2005. Cranial research focused on VR and resident education while spinal research focused on AR and neuronavigation. Female authorship was underrepresented. North America provides most of the high-impact research in this area.

Reliability of thoracolumbar burst fracture classification in the Swedish Fracture Register

BACKGROUND

The Swedish Fracture Register (SFR) is a national quality register for all types of fractures in Sweden. Spine fractures have been included since 2015 and are classified using a modified AOSpine classification. The aim of this study was to determine the accuracy of the classification of thoracolumbar burst fractures in the SFR.

METHODS

Assessments of medical images were conducted in 277 consecutive patients with a thoracolumbar burst fracture (T10-L3) identified in the SFR. Two independent reviewers classified the fractures according to the AOSpine classification, with a third reviewer resolving disagreement. The combined results of the reviewers were considered the gold standard. The intra- and inter-rater reliability of the reviewers was determined with Cohen's kappa and percent agreement. The SFR classification was compared with the gold standard using positive predictive values (PPV), Cohen's kappa and percent agreement.

RESULTS

The reliability between reviewers was  high (Cohen's kappa 0.70-0.97). The PPV for correctly classifying burst fractures in the SFR was high irrespective of physician experience (76-89%), treatment (82% non-operative, 95% operative) and hospital type (83% county, 95% university). The inter-rater reliability of B-type injuries and the overall SFR classification compared with the gold standard was low (Cohen's kappa 0.16 and 0.17 respectively).

CONCLUSIONS

The SFR demonstrates a high PPV for accurately classifying burst fractures, regardless of physician experience, treatment and hospital type. However, the reliability of B-type injuries and overall classification in the SFR was found to be low. Future studies on burst fractures using SFR data where classification is important should include a review of medical images to verify the diagnosis.

Back morphology and walking patterns mean 13.8 years after surgery for lumbar disk herniation in adolescents

Introduction

In many pain conditions, there is lingering pain despite healed tissue damage. Our previous study shows that individuals who underwent surgery for lumbar disk herniation (LDH) during adolescence have worse health, more pain, and increased disk degeneration mean 13 years after surgery compared with controls. It is unclear if walking patterns segregate surgically treated LDH adolescents and controls at mean 13-year follow-up.

Objectives

Here, we analyzed the relationship between gait, back morphology and other health outcomes in a cohort of individuals treated surgically because of lumbar disk herniation compared with controls.

Methods

We analyzed gait during a walking paradigm, back morphology at the site of surgery, and standardized health outcomes, among individuals who received surgery for LDH as adolescents, "cases" (n = 23), compared with "controls" (n = 23).

Results

There were gait differences in head (P = 0.021) and trunk angle (P = 0.021) between cases and controls in a direction where cases exhibited a posture associated with sickness. The gait variance was explained by subjective pain and exercise habits rather than objective disk degeneration.

Conclusion

Over a decade after surgery for LDH during adolescence, health among cases is worse compared with controls. The head and trunk angles differ between cases and controls, indicating that the residual pain lingers and may cause changes in movement patterns long after a painful episode in early life. Gait may be a useful target for understanding maintenance of pain and disability among individuals treated surgically for LDH during adolescence.

Dysphagia, health-related quality of life, and return to work after occipitocervical fixation

PURPOSE

The purpose of this study was to evaluate patient-reported outcome measures (PROMS) on dysphagia, health-related quality of life (HRQoL) and return to work after occipitocervical fixation (OCF). Postoperative radiographic measurements were evaluated to identify possible predictors of dysphagia.

METHODS

All individuals (≥ 18 years) who underwent an OCF at the study center or were registered in the Swedish spine registry (Swespine) between 2005 and 2019, and were still alive when the study was conducted, were eligible for inclusion. There was no overlap between the cohorts. Prospectively collected data on dysphagia (Dysphagia Short Questionnaire DSQ), HRQoL (EQ5D-3L) and return to work were used. Radiological and baseline patient data were retrospectively collected. In addition, HRQoL data of a matched sample of individuals was elicited from the Stockholm Public Health Survey 2006.

RESULTS

In total, 54 individuals were included. At long-term follow-up, 26 individuals (51%) had no dysphagia, and 25 (49%) reported some degree of dysphagia: 11 (22%) had mild dysphagia, and 14 (27%) had moderate to severe dysphagia. On a group level, the OCF sample scored significantly lower EQVAS and EQ-5Dindex values compared to the general population (60.0 vs. 80.0, p = 0.016; 0.43 vs. 0.80, p < 0.001). Individuals working preoperatively returned to work after surgery. Of those responding, 88% stated that they would undergo the OCF operation if it was offered today. No predictors of dysphagia based on radiographic measurements were identified.

CONCLUSION

Occipitocervical fixation results in a high frequency of long-term dysphagia. The HRQoL of OCF patients is significantly reduced compared to matched controls. However, most patients are satisfied with their surgery. No radiographic predictors of long-term dysphagia could be identified. Future prospective and systematic studies with larger samples and more objective outcome measures are needed to elucidate the causes of dysphagia in OCF.

The Effect of Concomitant Spinal Cord Injury on Postoperative Health-related Quality of Life After Traumatic Subaxial Cervical Spine Injuries: A Nationwide Registry Study

OBJECTIVE

To evaluate the effect of spinal cord injury (SCI) on the health-related quality of life (HRQoL) in patients surgically treated for traumatic subaxial cervical spine injuries and investigate the agreement between objective neurologic outcomes and patient reported outcome measures (PROMs) in that context.

STUDY DESIGN

Observational study on prospectively collected multi-institutional registry data.

SETTING

Sweden.

PARTICIPANTS

Patients with traumatic subaxial spine injuries identified in the Swedish Spine Registry (Swespine) between 2006 and 2016.

INTERVENTIONS

Anterior, posterior, or anteroposterior cervical fixation surgery.

MAIN OUTCOMES

Patient-reported outcome measures (PROMs) consisting of EQ-5D-3Lindex and Neck Disability Index (NDI).

RESULTS

Among the 418 identified patients, 93 (22%) had a concomitant SCI. In this group, 30 (32%) had a complete SCI (Frankel A), and the remainder had incomplete SCIs (17%) Frankel B; 25 (27%) Frankel C; 22 (24%) Frankel D. PROMs significantly correlated with the Frankel grade (P<.001). However, post hoc analysis revealed that the differences between adjacent Frankel grades failed to reach both statistical and clinical significance. On univariable linear regression, the Frankel grade was a significant predictor of a specific index derived from the EQ-5D-3L questionnaire (EQ-5D-3Lindex) at 1, 2, and 5 years postoperatively as well as the NDI at 1 and 2 years postoperatively (P<.001). Changes of PROMs over time from 1, to 2, and 5 years postoperatively did not reach statistical significance, regardless of the presence and degree of SCI (P>.05).

CONCLUSION

Overall, the Frankel grade significantly correlated with the EQ-5D-3Lindex and NDI and was a significant predictor of PROMs at 1, 2, and 5 years. PROMs were stable beyond 1 year postoperatively regardless of the severity of the SCI.

Lumbar degeneration and quality of life in patients with lumbar disc herniation: a case-control long-term follow-up study

BACKGROUND AND PURPOSE

Adults treated surgically for lumbar disc herniation in adolescence have a higher degree of lumbar disc degeneration than controls. We aimed to establish whether the degree of lumbar degeneration differs at diagnosis or at follow-up between surgically and non-surgically treated individuals.

METHODS

We identified individuals with a lumbar disc herniation in adolescence diagnosed with magnetic resonance imaging (MRI) and contacted them for follow-up MRI. Lumbar degeneration was assessed according to Pfirrmann, Modic, and total end plate score (TEP score). Patient-reported outcome measures at follow-up comprised the Oswestry Disability Index (ODI), EQ-5D-3-level version, 36-Item Short Form Health Survey (SF-36), and Visual Analogue Scale (VAS) for back and leg pain. Fisher's exact test, Mann-Whitney U tests, Wilcoxon tests, and logistic regression were used for statistical analysis.

RESULTS

MRIs were available at diagnosis and after a mean of 11.9 years in 17 surgically treated individuals and 14 non-surgically treated individuals. Lumbar degeneration was similar at diagnosis (P = 0.2) and at follow-up, with the exception of higher TEP scores in surgically treated individuals at levels L4-L5 and L5-S1 at follow-up (P ≤ 0.03), but this difference did not remain after adjustment for age and sex (P ≥ 0.8). There were no significant differences in patient-reported outcome measures between the groups at follow-up (all P ≥ 0.2).

CONCLUSION

Adolescents with a lumbar disc herniation have, irrespective of treatment, a similar degree of lumbar degeneration at the time of diagnosis, and similar lumbar degeneration and patient-reported outcomes at long-term follow-up.

The effect of minimally invasive sacroiliac joint fusion compared to sham operation: a double-blind randomized placebo-controlled trial

Background

Minimally invasive fusion of the sacroiliac joint as treatment for low back pain may reduce pain and improve function compared to non-operative treatment, although clear evidence is lacking. The aim of this trial was to evaluate the effect of minimally invasive sacroiliac joint fusion compared to sham surgery on sacroiliac joint pain reduction.

Methods

In this double-blind randomized sham surgery-controlled trial patients with clinical diagnosis of sacroiliac joint pain confirmed with sacroiliac joint injection were included at two university hospitals in Sweden and Norway. Patients were randomized by the operating surgeon at each site to minimally invasive sacroiliac joint fusion or sham surgery. The primary endpoint was group difference in sacroiliac joint pain on the operated side at six months postoperatively, measured by the Numeric Rating Scale (0-10). Un-blinding and primary analysis were performed when all patients had completed six months follow-up. The trial is closed for new participants and was registered at clinicaltrials.gov: NCT03507049.

Findings

Between September 1st, 2018 and October 22nd, 2021, 63 patients were randomized, 32 to the surgical group, 31 to the sham group. Mean age was 45 years (range 26-63) and 59 of 63 (94%) patients were female. The mean reduction in the operated sacroiliac joint from baseline to six months postoperative was 2.6 Numeric Rating Scale points in the surgical group and 1.7 points in the sham group (mean between groups difference -1.0 points; 95% CI, -2.2 to 0.3; p = 0.13).

Interpretation

This double-blind randomized controlled trial could not prove that minimally invasive fusion of the sacroiliac joint was superior to sham surgery at six months postoperative.

Funding

Sophies Minde Ortopedi supported a clinical research position for Engelke Marie Randers. Region Stockholm supported the cost for the Swedish ethical application and a clinical research appointment for Paul Gerdhem.

Association of genetic variation in COL11A1 with adolescent idiopathic scoliosis

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 COL11A1P1335L 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.

Spinal surgery and the risk of reoperation after total hip arthroplasty: a cohort study based on Swedish spine and hip arthroplasty registers

BACKGROUND AND PURPOSE

Studies suggest increased revision risk of total hip arthroplasty (THA) in individuals with lumbar spinal fusion, but studies including non-fused individuals are lacking. We aimed to investigate whether individuals undergoing lumbar spinal stenosis surgery with or without fusion are at an increased risk of reoperation before or after THA.

PATIENTS AND METHODS

The Swedish Spine Register and the Swedish arthroplasty register were searched from 2000 through 2021. Chi-square, Kaplan-Meier and binary multivariate logistic regression were used to compare reoperation rates up to 10 years after THA surgery.

RESULTS

7,908 individuals had undergone lumbar spinal stenosis surgery (LSSS) (fusion n = 1,281) and THA. LSSS before THA compared with THA-only controls was associated with a higher risk of THA reoperations: 87 (2%) out of 3,892 vs. 123 (1%) out of 11,662 (P < 0.001). LSSS after THA compared with THA-only controls was not associated with a higher risk of reoperation, confirmed by Kaplan- Meier analyses and binary multivariate logistic regression. Mortality was lower in individuals undergoing both LSSS and THA, regardless of procedure order. There was no difference in THA reoperations in individuals who had undergone LSSS before THA without fusion or with fusion. The individuals who had undergone LSSS after THA with fusion had an increased risk of THA reoperation compared with those without fusion.

CONCLUSION

LSSS with or without fusion before THA is associated with an increased risk of THA reoperation. Spinal fusion increased the risk of reoperation of THA when performed after THA.

Assessment of the sacroiliac joint with computed tomography motion analysis: a diagnostic study of 12 patients

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, and 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° (CI 0.43-0.71) vs. 0.20° (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° (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.

Nighttime Bracing or Exercise in Moderate-Grade Adolescent Idiopathic Scoliosis: A Randomized Clinical Trial

Importance

Moderate-grade adolescent idiopathic scoliosis (AIS) may be treated with full-time bracing. For patients who reject full-time bracing, the effects of alternative, conservative interventions are unknown.

Objective

To determine whether self-mediated physical activity combined with either nighttime bracing (NB) or scoliosis-specific exercise (SSE) is superior to a control of physical activity alone (PA) in preventing Cobb angle progression in moderate-grade AIS.

Design, Setting, and Participants

The Conservative Treatment for Adolescent Idiopathic Scoliosis (CONTRAIS) randomized clinical trial was conducted from January 10, 2013, through October 23, 2018, in 6 public hospitals across Sweden. Male and female children and adolescents aged 9 to 17 years with an AIS primary curve Cobb angle of 25° to 40°, apex T7 or caudal, and skeletal immaturity based on estimated remaining growth of at least 1 year were included in the study. Dates of analysis were from October 25, 2021, to January 28, 2023.

Interventions

Interventions included self-mediated physical activity in combination with either NB or SSE or PA (control). Patients with treatment failure were given the option to transition to a full-time brace until skeletal maturity.

Main Outcomes and Measures

The primary outcome was curve progression of 6° or less (treatment success) or curve progression of more than 6° (treatment failure) seen on 2 consecutive posteroanterior standing radiographs compared with the inclusion radiograph before skeletal maturity. A secondary outcome of curve progression was the number of patients undergoing surgery up until 2 years after the primary outcome.

Results

The CONTRAIS study included 135 patients (45 in each of the 3 groups) with a mean (SD) age of 12.7 (1.4) years; 111 (82%) were female. Treatment success was seen in 34 of 45 patients (76%) in the NB group and in 24 of 45 patients (53%) in the PA group (odds ratio [OR], 2.7; 95% CI, 1.1-6.6). The number needed to treat to prevent curve progression with NB was 4.5 (95% CI, 2.4-33.5). Treatment success occurred in 26 of 45 patients (58%) in the SSE group (OR for SE vs PA, 1.2; 95% CI, 0.5-2.8). Up to 2 years after the primary outcome time point, 9 patients in each of the 3 groups underwent surgery.

Conclusions and Relevance

In this randomized clinical trial, treatment with NB prevented curve progression of more than 6° to a significantly higher extent than did PA, while SSE did not; in addition, allowing transition to full-time bracing after treatment failure resulted in similar surgical frequencies independent of initial treatment. These results suggest that NB may be an effective alternative intervention in patients rejecting full-time bracing.

Trial Registration

ClinicalTrials.gov Identifier: NCT01761305.

Association of genetic variation in COL11A1 with adolescent idiopathic scoliosis

Adolescent idiopathic scoliosis (AIS) is a common and progressive spinal deformity in children that exhibits striking sexual dimorphism, with girls at more than five-fold 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 (IVD)-vertebral junction region encompassing the growth plate, with less collagen (α1) XI detected in Pax1-/- spines compared to wildtype. By genetic targeting we found that wildtype Col11a1 expression in costal chondrocytes suppresses expression of Pax1 and of Mmp3, encoding the matrix metalloproteinase 3 enzyme implicated in matrix remodeling. However, this suppression was abrogated in the presence of the AIS-associated COL11A1P1335L 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.

Correction: Dufvenberg et al. Six-Month Results on Treatment Adherence, Physical Activity, Spinal Appearance, Spinal Deformity, and Quality of Life in an Ongoing Randomised Trial on Conservative Treatment for Adolescent Idiopathic Scoliosis (CONTRAIS). J. Clin. Med. 2021, 10, 4967

In the original publication [...].

Distal fusion level, complications, and reoperations in individuals with cerebral palsy undergoing surgery for scoliosis

PURPOSE

To compare radiological outcome, complications and reoperations in individuals with cerebral palsy and scoliosis fused to the fifth lumbar vertebra (L5), the sacrum, or the ilia.

METHODS

208 individuals were identified in the national quality registry Swespine. Lowest level of fusion was L5 in 58, the sacrum in 92, and the ilia in 58 individuals. A subanalysis on 58 matched pairs operated to L5 or the pelvis (sacrum = 42, ilia = 16) with similar pelvic obliquity (± 5°) was performed.

RESULTS

The median (interquartile range) follow-up for the last radiograph was 1.7 (1.7) years and for reoperations 6.0 (5.9) years. Preoperatively, median Cobb angle of the major curve was 65° (23°) in the L5 group, 68° (28°) in the sacrum group, and 78° (25°) in the ilia group (p = 0.006). Preoperative median pelvic obliquity according to Maloney was 16° (19°), 21° (13°), and 27° (28°), respectively (p = 0.004). Immediate postoperative Cobb angles were 28° (18°), 28° (16°), and 32° (25°), respectively (p = 0.11). Immediate postoperative pelvic obliquity was 7° (10°), 7° (8°), and 8° (10°), respectively (p = 0.28). The median change in pelvic obliquity from the first to the last postoperative radiograph was - 5° (7°), - 3° (6°), - 3° (6°), respectively (p = 0.55). 7 (12%), 11 (12%), and 7 (12%) patients required at least one reoperation (p = 1.0), respectively. In the matched analysis, no significant differences in the radiological outcomes were found (all p ≥  0.38).

CONCLUSIONS

Maintained curve and pelvic obliquity correction with no significant difference in complication and reoperation rates were found irrespective of distal fusion level.

Magnetically controlled growing rod treatment for early-onset scoliosis: analysis of 52 consecutive cases demonstrates improvement of coronal deformity

Background

The purpose of this study was to report the radiographic results and complications of magnetically controlled growing rod (MCGR) treatment in patients with early-onset scoliosis (EOS).

Methods

Patient records and radiographs from a consecutive series of patients treated with MCGR for EOS at two Swedish institutions were reviewed retrospectively. Radiographic analysis included Cobb angle, T1-T12 height, T1-S1 height, thoracic kyphosis, and lung height. Subgroup analyses were performed on primary versus conversion cases and single versus dual rods using one-way analysis of variance (ANOVA) and independent samples t-test.

Results

Fifty-two cases treated with MCGR (24 single rods, 28 dual rods) were included from local surgical records into this cohort study, 32 primary and 20 converted from other growth friendly surgical treatment. Mean age at MCGR implantation was 7.4 (2.0-14.6) years old in the primary group and 9.3 (5.0-16.1) years old in the converted group. Mean follow-up time was 3.7 (2.0-7.6) years. Mean (standard deviation; SD) Cobb angle of the major curve changed from 62° (17°) preoperatively to 42° (16°) postoperatively to 46° (18°) at final follow-up (P<0.001). Mean (SD) overall thoracic kyphosis changed from 41° (19°) preoperatively to 32° (14°) postoperatively to 39° (17°) at final follow-up (P=0.018). Mean T1-T12 height was 177 mm (34 mm) preoperatively, 183 mm (35 mm) immediate postoperative and 199 mm (35 mm) at final follow-up (P=0.047). The mean T1-T12 height increased significantly in the primary group but not in the converted group. The number of surgeries was 114 (78 planned, 36 unplanned). The rate of unplanned surgeries did not differ significantly between single and dual rods. The total number of complications was 70 of which 38 were implant related. The overall mean complication rate was 1.4 (0-4). There were no significant differences in complication rates between subgroups.

Conclusions

MCGR treatment enabled and maintained correction of spinal deformity while allowing spinal growth. There were no significant differences in complication rates or unplanned surgeries between the groups treated with single or dual rods.

Minimally Invasive Surgery for Thoracolumbar Spinal Fractures in Patients With Ankylosing Spondylitis

BACKGROUND

Patients with ankylosing spondylitis (AS) are prone to spinal fractures even after low-energy trauma. Posterior fusion through open surgery has been the standard procedure for spinal fractures in patients with AS. Minimally invasive surgery (MIS) has been proposed as an alternative treatment option. There are few literature reports regarding patients with AS being treated for spinal fractures with MIS. This study aims to present the clinical outcome of a series of patients with AS treated with MIS for spinal fractures.

METHODS

We included a consecutive series of patients with AS who underwent MIS for thoracolumbar fractures between 2014 and 2021. The median follow-up was 38 (12-75) months. Medical records and radiographs were reviewed, and data on surgery, reoperations, complications, fracture healing, and mortality were recorded.

RESULTS

Forty-three patients (39 [91%] men) were included with a median (range) age of 73 (38-89) years. All patients underwent image-guided MIS with screws and rods. Three patients underwent reoperations, all due to wound infections. One patient (2%) died within 30 days and 7 (16%) died within the first year after surgery. Most patients with a radiographic follow-up of 12 months or more (29/30) healed with a bony fusion on computed tomography (97%).

CONCLUSION

Patients with AS and a spinal fracture are at risk of reoperation and have significant mortality during the first year. MIS provides adequate surgical stability for fracture healing with an acceptable number of complications and is an adequate choice in treating AS-related spinal fractures.

LEVEL OF EVIDENCE: 4

Surgical and Health-related Quality of life Outcomes in Children With Congenital Scoliosis During 5-year Follow-up. Comparison to Age and Sex-matched Healthy Controls

BACKGROUND

Congenital spinal anomalies represent a heterogeneous group of spinal deformities, of which only progressive or severe curves warrant surgical management. Only a limited number of studies have investigated the impact of surgery on the health-related quality of life and very limited data exists comparing these outcomes to healthy controls.

METHODS

A single surgeon series of 67 consecutive children with congenital scoliosis (mean age at surgery 8.0 y, range: 1.0 to 18.3 y, 28 girls) undergoing hemivertebrectomy (n = 34), instrumented spinal fusion (n = 20), or vertical expandable prosthetic titanium rib procedure (n = 13) with a mean follow-up of 5.8 years (range: 2 to 13 y). The comparison was made to age and sex-matched healthy controls. Outcome measures included the Scoliosis Research Society questionnaire both pre and postoperatively, radiographic outcomes, and complications.

RESULTS

The average major curve correction was significantly better in the hemivertebrectomy (60%) and instrumented spinal fusion (51%) than in the vertical expandable prosthetic titanium rib group (24%), respectively ( P < 0.001). Complications were noted in 8 of 67 (12%) children, but all patients recovered fully during follow-up. Pain, self-image, and function domains improved numerically from preoperative to final follow-up, but the pain score was the only one with a statistically significant change ( P = 0.033). The Scoliosis Research Society pain, self-image, and function domain scores remained at a significantly lower level at the final follow-up than in the healthy controls ( P ≤ 0.05), while activity scores improved to a similar level.

CONCLUSIONS

Surgery for congenital scoliosis improved angular spinal deformities with a reasonable risk of complications. Health-related quality of life outcomes improved from preoperative to final follow-up, but especially pain and function domains remained at a significantly lower level than in the age and sex-matched healthy controls.

LEVEL OF EVIDENCE

Level III, therapeutic.

Outcome and Health-Related Quality of Life After Combined Anteroposterior Surgery Versus Anterior Surgery Alone in Subaxial Cervical Spine Fractures : Analysis of a National Multicenter Data Set

STUDY DESIGN

Observational study on prospectively collected data.

OBJECTIVES

To compare patient-reported outcomes and complications after anteroposterior surgery or anterior surgery in subaxial cervical spine fractures.

SUMMARY OF BACKGROUND DATA

There is no consensus regarding the optimal surgical approach for subaxial cervical spine fractures. Although anterior surgery is often sufficient to restore stability, anteroposterior surgery is sometimes preferred in severe instability. The effects of a more extensive procedure on patient-reported outcomes have not been investigated. We hypothesized that patient-reported outcomes and complication rates were similar between these surgical approaches.

MATERIALS AND METHODS

Individuals treated with either a combined anteroposterior or anterior surgery alone between 2006 and 2016 and with at least 1-year follow-up were identified in the Swedish Spine Registry. Cases were matched 1:2 for age (±5 y). Outcomes were Neck Disability Index (NDI), EQ-5D-3L index, satisfaction, reoperations, and surgeon-reported and patient-reported complications within 90 days. Mann-Whitney U -tests and χ 2 tests were used in statistical comparisons.

RESULTS

The median [interquartile range] number of instrumented vertebrae was 3 [2-5.5] in the anteroposterior group and 2 [2-3] in the anterior group ( P <0.001). The mean±SD follow-up time was 3.5±2.3 years in the anteroposterior and 3.8±2.0 years in the anterior group ( P =0.39), respectively. At follow-up, Neck Disability Index was 20 [6-37] in the anteroposterior group and 18 [3.5-40] in the anterior group ( P =0.69), and the median EQ-5D-3L index was 0.73 [0.12-0.80] in the anteroposterior group and 0.75 [0.62-0.89] in the anterior group ( P =0.27). Satisfaction with the treatment was reported by 90% in the anteroposterior group and by 87% in the anterior group ( P =0.98). None of the individuals in the anteroposterior and 6 of the individuals in the anterior group were reoperated ( P =0.18).

CONCLUSION

Patients operated on with anteroposterior or anterior surgery for subaxial cervical spine fractures are equally satisfied and report similar health-related quality of life measures.

Back Pain and Quality of Life 10 Years After Segmental Pedicle Screw Instrumentation for Adolescent Idiopathic Scoliosis

STUDY DESIGN

Comparative cohort study.

OBJECTIVE

The aim of the present study was to evaluate pain and health-related quality of life (HRQoL) in surgically managed patients with a minimum follow-up of 10 years compared with patients with untreated adolescent idiopathic scoliosis (AIS) and a healthy control group.

SUMMARY OF BACKGROUND DATA

Posterior spinal fusion with pedicle screws is the standard treatment for AIS, although it remains unclear whether this procedure results in improved long-term HRQoL compared with untreated patients with AIS.

PATIENTS AND METHODS

Sixty-four consecutive patients at a minimum follow-up of 10 years, who underwent posterior pedicle screw instrumentation for AIS were prospectively enrolled. Fifty-three (83%) of these patients completed Scoliosis Research Society (SRS) 24 questionnaires, clinical examination, and standing spinal radiographs. Pain and HRQoL were compared with age and sex-matched patients with untreated AIS and healthy individuals.

RESULTS

The mean major curve was 57° preoperatively and 15° at the 10-year follow-up. SRS-24 self-image domain score showed a significant improvement from preoperative to 2 years and remained significantly better at the 10-year follow-up ( P < 0.001). Patients fused to L3 or below had lower pain, satisfaction, and total score than patients fused to L2 or above ( P < 0.05), but self-image, function, and activity scores did not differ between groups at 10-year follow-up. Pain, self-image, general activity, and total SRS domains were significantly better at 10-year follow-up in the surgically treated patients as compared with untreated patients (all P < 0.05). Healthy controls had significantly higher total score s than those surgically treated at 10-year follow-ups ( P < 0.001).

CONCLUSION

Patients undergoing segmental pedicle screw instrumentation for AIS maintain high-level HRQoL during a 10-year follow-up. Their HRQoL was significantly better than in the untreated patients with AIS, except for the function domain. However, HRQoL remained at a lower level than in healthy controls.

Evolution of Patient-Reported Outcome Measures, 1, 2, and 5 years after Surgery for Subaxial Cervical Spine Fractures, A Nation-Wide Registry Study

BACKGROUND CONTEXT

A longer duration of patient follow-up arguably provides more reliable data on the long-term effects of a treatment. However, the collection of long-term follow-up data is resource demanding and often complicated by missing data and patients being lost to follow-up. In surgical fixation for cervical spine fractures, data are lacking on the evolution of patient reported outcome measures (PROMs) beyond 1-year of follow-up. We hypothesized that the PROMs would remain stable beyond the 1-year postoperative follow-up mark, regardless of the surgical approach.

PURPOSE

To assess the trends in the evolution of patient-reported outcome measures (PROMs) at 1, 2-, and 5-years following surgery in patients with traumatic cervical spine injuries.

STUDY DESIGN

Nation-wide observational study on prospectively collected data.

PATIENT SAMPLE

Individuals treated for subaxial cervical spine fractures with anterior, posterior, or combined anteroposterior approaches, between 2006 and 2016 were identified in the Swedish Spine Registry (Swespine).

OUTCOME MEASURES

PROMs consisting of EQ-5D-3L_index and the Neck Disability Index (NDI) were considered.

METHODS

PROMs data were available for 292 patients at 1 and 2 years postoperatively. Five-years PROMs data were available for 142 of these patients. A simultaneous within-group (longitudinal) and between group (approach-dependent) analysis was performed using mixed ANOVA. The predictive ability of 1-year PROMs was subsequently assessed using linear regression.

RESULTS

Mixed ANOVA revealed that PROMs remained stable from 1- to 2-years as well as from 2- to 5-years postoperatively and were not affected by the surgical approach (p<0.05). A strong correlation was found between 1-year and both 2- and 5-years PROMs (R>0.7; p<0.001). Linear regression confirmed the accuracy of 1-year PROMs in predicting both 2- and 5-years PROMs (p<0.001).

CONCLUSION

PROMs remained stable beyond 1-year of follow-up in patients treated with anterior, posterior, or combined anteroposterior surgeries for subaxial cervical spine fractures. The 1-year PROMs were strong predictors of PROMs measured at 2, and 5 years. The 1-year PROMs were sufficient to assess the outcomes of subaxial cervical fixation irrespective of the surgical approach.

Patient-reported Data as Predictors of Surgical Outcome in Patients With Degenerative Cervical Myelopathy: Analysis of a National Multicenter Dataset

STUDY DESIGN

Retrospective study design on prospectively collected registry data.

OBJECTIVE

To investigate whether improvement after surgery for degenerative cervical myelopathy is associated with preoperative disease severity and to identify predictors of outcome.

SUMMARY OF BACKGROUND DATA

Degenerative cervical myelopathy is the most common cause of spinal cord compromise in adults and surgery is often the treatment of choice. Identifying predictors may help to improve patient selection.

MATERIALS AND METHODS

This nationwide study from the Swedish spine registry included 901 patients treated surgically for degenerative cervical myelopathy. To investigate improvement in different disease severity groups, the individuals were divided into quartiles based on their preoperative European Myelopathy Scale (EMS) and EuroQol-5 Dimension (EQ-5D) index. Statistical analyses were made with analysis of variance, χ 2 , McNemar, and t tests. Multivariable linear or logistic regression was used to identify predictors for one-year improvement in EMS and EQ-5D index, and satisfaction at one year. In the regressions, the patient-reported outcome measures were dichotomized at their median, except improvement in EMS.

RESULTS

All patient-reported outcome measures improved from baseline to the one-year follow-up ( P <0.001). Statistically significant outcome improvements were seen in all disease severity groups. Preoperative low EMS (β=-1.37, P <0.001), long walking distance (<500 vs. >500 m; β=0.44, P =0.030), and low NDI (β=-0.43, P =0.048) were independent predictors of improvement in EMS. R2 was 0.11 for the multivariable model. Preoperative low EQ-5D index (odds ratio=0.11; 95% confidence interval: 0.07-0.16) and low NDI (0.56; 0.36-0.88) were independent predictors of improvement in EQ-5D index. Preoperative high EMS (1.86; 1.20-2.90) and shorter arm pain duration [<12 vs. >12 months (0.54; 0.33-0.88)] were independent predictors of satisfaction.

CONCLUSIONS

Postoperative improvement was seen over the whole range of disease severity. Disease severity, symptom duration, and walking distance were predictors of outcome in patients treated surgically for degenerative cervical myelopathy.

LEVEL OF EVIDENCE

III.

PREventing Mild Idiopathic SCOliosis PROgression (PREMISCOPRO): A protocol for a randomized controlled trial comparing scoliosis-specific exercises with observation in mild idiopathic scoliosis

BACKGROUND

Idiopathic scoliosis is the most common spinal deformity in children. Treatment strategies aim to halt progression of the curve. Mild scoliosis is in many cases observed or, in some cases, treated with scoliosis-specific exercises. More severe curves are treated mainly with a brace. The aim of this study is to investigate the effectiveness of scoliosis-specific exercises compared to observation in adolescents with mild idiopathic scoliosis.

METHODS

Subjects. Previously untreated and skeletally immature children aged 9-15 years of age with idiopathic scoliosis (curve magnitude Cobb 15-24 degrees) will be included. A total of 90 subjects will be included to receive one of two possible interventions. Interventions. Both groups will receive a physical activity prescription according to the World Health Organization recommendations. The intervention group will receive an additional active self-correction treatment strategy for curve correction and will have outpatient sessions once every two weeks for the first three months. They will be prescribed to do the exercises at least three times per week. The intervention will be performed until skeletal maturity or progression of the curve. Outcome. The subjects will participate in the study until curve progression or until skeletal maturity (defined as less than 1 cm growth for six months). The primary outcome variable is failure of treatment, defined as progression of the Cobb angle more than 6 degrees on two consecutive x-rays compared to the baseline x-ray. Secondary outcome measures include patient-reported outcomes, clinical characteristics (i.e. angle of trunk rotation and trunk asymmetry) and number requiring brace treatment. Clinical follow-ups will be performed every six months and radiographs will be taken annually.

DISCUSSION

This study will compare effectiveness of an active self-corrective exercise strategy in mild idiopathic scoliosis with observation in terms of halting curve progression.

Serum metal ion levels following spinal deformity surgery: a case-control study of 182 individuals

PURPOSE

The aim of this study is to evaluate the levels of chromium (Cr), cobalt (Co), and titanium (Ti) after instrumented fusion for scoliosis.

METHODS

Serum samples were collected at median 2.24 (range 0.1-38.8) years after fusion surgery for scoliosis in 91 individuals, of which 71 had been treated with steel implants and 20 with titanium implants. 91 sex and age-matched non-surgically treated individuals with scoliosis were used as controls. Levels of Cr, Co, and Ti were measured.

RESULTS

In the 91 surgically treated individuals median levels of Cr were 0.54 µg/l vs 0 µg/l in the 91 controls, p < 0.001. Corresponding results for Co were 0.29 µg/l vs. 0.24 µg/l, p = 0.19, and for Ti were 0 µg/l vs. 0 µg/l, p < 0.001. In the individuals with steel implants and their corresponding controls median Cr levels were 0.63 µg/l vs. 0.00 µg/l, p < 0.001 and Co levels 0.27 µg/l vs. 0.23 µg/l, p = 0.36. No Ti was detected. In the individuals with titanium implants, median Cr levels were 0 µg/l vs. 0 µg/l in their corresponding controls, p = 0.38. Corresponding results for Co was 0.39 µg/l vs. 0.31 µg/l, p = 0.27 and for Ti 4.31 µg/l vs. 0 µg/l, p < 0.001. In the individuals with steel implants a negative correlation between implant time in situ and levels of Cr was found ([Formula: see text] = - 0.52, p < 0.001) but not with Co ([Formula: see text] = - 0.14, p = 0.23). Ti was not detected. In the individuals with titanium implants, there was no correlation between implant time in situ and levels of Cr ([Formula: see text] = 0.36, p = 0.12), Co ([Formula: see text] = - 0.12, p = 0.60) or Ti ([Formula: see text] = 0.22, p = 0.35).

CONCLUSION

The use of stainless steel and titanium implants in spinal fusion surgery is associated with elevated metal ion concentrations several years after surgery.

Bone Turnover Marker Profiling and Fracture Risk in Older Women: Fracture Risk from Age 75 to 90

PURPOSE

A major challenge in osteoporosis is to identify individuals at high fracture risk. We investigated six bone turnover markers (BTMs) to determine association with specific fracture types; the time-frame for risk prediction and whether these are influenced by age at assessment.

METHODS

Population-based OPRA cohort (n = 1044) was assessed at ages 75, 80, 85 and fractures documented for up to 15 years. Six BTMs were analyzed at each time-point (N-terminal propeptide of type I collagen, PINP; total osteocalcin, OC; bone-specific alkaline phosphatase, BALP; C-terminal telopeptide of type I collagen, CTX; tartrate-resistant acid phosphatase 5b, TRAcP5b; urinary osteocalcin). Hazard ratios (HR) for any, major osteoporotic, vertebral and hip fractures were calculated as short (1, 2, 3 years) and long-term risk (5, 10, 15 years).

RESULTS

At 75 year, high CTX levels were associated with an increased risk of all fractures, including major osteoporotic fractures, across most time-frames (HRs ranging: 1.28 to 2.28). PINP was not consistently associated. Urinary osteocalcin was consistently associated with elevated short-term risk (HRs ranging: 1.83-2.72). Other BTMs were directionally in accordance, though not all statistically significant. BTMs were not predictive for hip fractures. Association of all BTMs attenuated over time; at 80 year none were associated with an increased fracture risk.

CONCLUSION

CTX, urinary OC and TRAcP5b are predictive for fracture in a 1 to 3 year, perspective, whereas in the long-term or above age 80 years, BTMs appear less valuable. Resorption markers, particularly CTX, were more consistently associated with fracture risk than formation markers in the very elderly.

Postoperative outcomes of pedicle screw instrumentation for adolescent idiopathic scoliosis with and without a subfascial wound drain: a multicentre randomized controlled trial

AIMS

The aim of this study was to evaluate whether, after correction of an adolescent idiopathic scoliosis (AIS), leaving out the subfascial drain gives results that are no worse than using a drain in terms of total blood loss, drop in haemoglobin level, and opioid consumption.

METHODS

Adolescents (aged between 10 and 21 years) with an idiopathic scoliosis (major curve ≥ 45°) were eligible for inclusion in this randomized controlled noninferiority trial (n = 125). A total of 90 adolescents who had undergone segmental pedicle screw instrumentation were randomized into no-drain or drain groups at the time of wound closure using the sealed envelope technique (1:1). The primary outcome was a drop in the haemoglobin level during first three postoperative days. Secondary outcomes were 48-hour postoperative oxycodone consumption and surgical complications.

RESULTS

All 90 patients were included in the primary outcome analysis (no drain = 43; drain = 47). The mean total postoperative blood loss (intraoperative and drain output) was significantly higher in the group with a subfascial drain than in the no-drain group (1,008 ml (SD 520) vs 631 ml (SD 518); p < 0.001). The drop in haemoglobin level did not differ between the study groups over the postoperative timepoints (p = 0.290). The 48-hour opioid consumption was significantly higher in the no-drain group (2.0 mg/kg (SD 0.9) vs 1.4 (SD 0.6); p = 0.005). Two patients in the no-drain and one patient in the drain group developed a surgical site infection.

CONCLUSION

Leaving the subfascial drain out after pedicle screw instrumentation for AIS is not associated with higher postoperative haemoglobin levels. Patients treated without a subfascial drain needed 30% more opioids during the first 48 hours than those who had a drain.Cite this article: Bone Joint J 2022;104-B(9):1067-1072.

Health-related quality of life outcomes in adolescent Scheuermann's kyphosis patients treated with posterior spinal fusion: A comparison with age- and sex-matched controls

PURPOSE

To assess the health-related quality of life and radiographic outcomes of surgically treated adolescent Scheuermann's kyphosis patients after minimum of 2-year follow-up and to compare the health-related quality of life with age- and sex-matched healthy controls.

METHODS

Twenty-two consecutive adolescents (mean age = 16.7 years) undergoing posterior spinal fusion for Scheuermann's kyphosis were included and matched by age and sex with two healthy controls. The health-related quality of life was evaluated using the Scoliosis Research Society-24 questionnaire. Radiographic parameters were measured for comparison preoperatively and at 6 months and 2-year follow-ups. The health-related quality of life parameters were compared with healthy controls at 2 years of follow-up.

RESULTS

The mean maximal thoracic kyphosis improved from 79° (range = 75°-90°) to 55° (range = 45°-75°) (p < 0.001), and the mean lumbar lordosis was reduced from 71° (range = 51°-107°) to 52° (range = 34°-68°) (p < 0.001) after 2 years postoperatively. Incidence of proximal junctional kyphosis (PJK) was 18%. The scores of the Scoliosis Research Society-24 improved, with statistical significance observed in pain and self-image domains from preoperative to 2-year follow-up (p = 0.002 in both domains). The self-image and function were significantly lower in the operated patients at their 2-year follow-up visit compared to controls (p = 0.023 for self-image and p < 0.001 for function).

CONCLUSION

Instrumented posterior spinal fusion improves the health-related quality of life of Scheuermann's kyphosis patients during the 2-year follow-up. The greatest improvement is observed in pain and self-image domains. The health-related quality of life in pain and activity domains reaches the level of healthy individuals, while function and self-image remain at a statistically lower level.

Idiopathic scoliosis: a systematic review and meta-analysis of heritability

Purpose

Methods

Results

Conclusion

Effectiveness of laminectomy with fusion and laminectomy alone in degenerative cervical myelopathy

PURPOSE

The effectiveness of laminectomy with fusion and laminectomy alone in degenerative cervical myelopathy was compared.

METHODS

Individuals treated with laminectomy with fusion or laminectomy alone at or below the second cervical vertebra were identified in the Swedish spine registry. 66 individuals treated with laminectomy and instrumented fusion were age matched to 132 individuals treated with laminectomy alone. The European Myelopathy Scale (EMS), the Neck Disability Index (NDI), the Numeric Rating Scale (NRS) for neck pain and the EQ-5D index were available at baseline, and at 1 and 2 year follow-ups. Statistical analyses were performed with Mann-Whitney U tests and paired T tests. Effect sizes were described with Cohen's D.

RESULTS

Data at baseline did not differ significantly between the groups with the exception of a longer laminectomy in the fusion group (4.2 vs 3.4 vertebras; p < 0.001). Both groups improved EMS, NDI, NRS and EQ-5D from baseline to 1 year (p ≤ 0.011), with no additional improvement between 1 and 2 years (all p ≥ 0.09). Effect sizes for change from baseline were small to medium in both groups. At 2 years the laminectomy with fusion group and the laminectomy alone group had a median (25th;75th percentile) EMS of 13 (11;13) and 13 (11;15) (p = 0.77), NDI of 39 (24;54) and 27 (10;41) (p = 0.045), NRS of 4 (1;2) and 2 (0;5) (p = 0.048), and EQ-5D index of 0.67 (0.25;0.73) and 0.66 (0.17;0.76) (p = 0.96).

CONCLUSION

The results of this study suggest similar effectiveness of laminectomy with instrumented fusion and laminectomy alone in degenerative cervical myelopathy.

LEVEL OF EVIDENCE

III.

Study protocol: The SunBurst trial-a register-based, randomized controlled trial on thoracolumbar burst fractures

BACKGROUND AND PURPOSE

The treatment for patients with thoracolumbar burst fractures without neurological deficit or complete rupture of the posterior ligament complex (PLC) is controversial and includes both surgical and non-surgical options. Current evidence on which treatment is optimal remains inconclusive. In this study we compare surgical with non-surgical treatment.

METHODS

The study is a nationwide, multicenter, register-based randomized controlled trial (R-RCT). Patients with a thoracolumbar burst fracture will be identified by the Swedish Fracture Register. The admitting physician will be notified during the registration process and the patient will be screened for eligibility. Patients, 18 to 66 years old without neurologic deficit to more than a single nerve root and without complete rupture of the PLC, are eligible for the study. 202 patients will be randomized in a 1:1 relation to either surgical or non-surgical treatment. Patient-reported outcome measures (PROMs), including the Oswestry Disability Index (ODI) and radiological data, will be collected at the time of injury, after 3-4 months, and after 1 year. Additional data from national health registries will be collected after 1 year.

OUTCOME

The primary outcome is the ODI 1 year after injury. Secondary outcomes include additional PROMs, adverse events, drug consumption, sick leave, healthcare consumption, and imaging data.

INTERPRETATION

The primary outcome is the ODI 1 year after injury. Secondary outcomes include additional PROMs, adverse events, drug consumption, sick leave, healthcare consumption, and imaging data. Estimated duration - The study started on September 1, 2021 and will continue for approximately 4 years. Trial registration - The trial is registered at www.clinicaltrials.com, NCT05003180.

Learning from the past to plan for the future: A scoping review of musculoskeletal clinical research in Sweden 2010-2020

BACKGROUND

The aims of this study are to 1) determine the scope of musculoskeletal (MSK)-related clinical research in Sweden; 2) collate the amount of first-tier funding received; 3) discuss strategies and infrastructure supporting future MSK clinical trials in Sweden.

METHODS

A systematic scoping review protocol was applied in PubMed, Scopus, and SweCRIS databases. The articles were examined, and data were extracted in multiple stages by three blinded authors.

RESULTS

The search strategy resulted in 3,025 publications from 479 Swedish-affiliated authors. Primary health care was the basis for 14% of the publications, 84% from secondary health care, and 2% from occupational health care with a similar proportional distribution of first-tier research grant financing. Approximately one in six publications were randomized controlled trials (RCTs), while the majority were of observational cohort design. The majority of publications in primary and occupational health care were related to pain disorders (51 and 67%, respectively), especially diagnosis, prognosis, and healthcare organizational-related interventions (34%) and rehabilitation (15%) with similar proportional distribution of first-tier research grant financing. In secondary health care, rheumatic inflammatory disorder-related publications were most prevalent (30%), most frequently concerning diagnosis, prognosis, and healthcare organizational-related interventions (20%), attracting approximately half of all first-tier funding. Publications related to degenerative joint disorders (25%), fractures (16%), and joint, tendon, and muscle injuries (13%) frequently concerned surgical and other orthopedic-related interventions (16, 6, and 8%, respectively). Pain disorder-related publications (10%) as well as bone health and osteoporosis-related publications (4%) most frequently concerned diagnosis, prognosis, and healthcare organizational-related interventions (5 and 3%, respectively).

CONCLUSIONS

Swedish-affiliated MSK disorder research 2010-2020 was predominantly observational cohort rather than RCT based. There was skewed first-tier funding allocation considering prevalence/incidence and burden of disease. Use of infrastructure supporting register-based RCTs, placebo-controlled RCTs, and hybrid effectiveness-implementation studies on prevention and clinical intervention is important strategies for the future in all healthcare sectors.

MRI Characteristics at a Mean of Thirteen Years After Lumbar Disc Herniation Surgery in Adolescents: A Case-Control Study

The purpose of this study was to describe the prevalence of lumbar spine degeneration in adult individuals who had undergone lumbar disc herniation surgery during adolescence.

Six-Month Results on Treatment Adherence, Physical Activity, Spinal Appearance, Spinal Deformity, and Quality of Life in an Ongoing Randomised Trial on Conservative Treatment for Adolescent Idiopathic Scoliosis (CONTRAIS)

Adolescents with idiopathic scoliosis (AIS) often receive conservative treatments aiming to prevent progression of the spinal deformity during puberty. This study aimed to explore patient adherence and secondary outcomes during the first 6 months in an ongoing randomised controlled trial of three treatment interventions. Interventions consisted of physical activity combined with either hypercorrective Boston brace night shift (NB), scoliosis-specific exercise (SSE), or physical activity alone (PA). Measures at baseline and 6 months included angle of trunk rotation (ATR), Cobb angle, International Physical Activity Questionnaire short form (IPAQ-SF), pictorial Spinal Appearance Questionnaire (pSAQ), Scoliosis Research Society (SRS-22r), EuroQol 5-Dimensions Youth (EQ-5D-Y) and Visual Analogue Scale (EQ-VAS). Patient adherence, motivation, and capability in performing the intervention were reported at 6 months. The study included 135 patients (111 females) with AIS and >1-year estimated remaining growth, mean age 12.7 (1.4) years, and mean Cobb angle 31 (±5.3). At 6 months, the proportion of patients in the groups reporting high to very high adherence ranged between 72 and 95%, while motivation ranged between 65 and 92%, with the highest proportion seen in the NB group (p = 0.014, p= 0.002). IPAQ-SF displayed significant between group main effects regarding moderate activity (F = 5.7; p = 0.004; ηp2 = 0.10), with a medium-sized increase favouring the SSE group compared to NB. Walking showed significant between group main effects, as did metabolic equivalent (MET-min/week), with medium (F = 6.8, p = 0.002; ηp2 = 0.11, and large (F = 8.3, p = < 0.001, ηp2 = 0.14) increases, respectively, for the SSE and PA groups compared to NB. From baseline to 6 months, ATR showed significant between group medium-sized main effects (F = 1.2, p = 0.019, ηp2 = 0.007) favouring the NB group compared to PA, but not reaching a clinically relevant level. In conclusion, patients reported high adherence and motivation to treatment, especially in the NB group. Patients in the SSE and PA groups increased their physical activity levels without other clinically relevant differences between groups in other clinical measures or patient-reported outcomes. The results suggest that the prescribed treatments are viable first-step options during the first 6 months.

Parathyroid Hormone Disturbances in Postmenopausal Women with Distal Forearm Fracture

Background

Primary hyperparathyroidism (PHPT) is a common endocrine disorder with a wide range of adverse effects, such as osteoporosis. Many women are not diagnosed due to asymptomatic disease or vague symptoms but are still at risk of severe adverse effects. Early identification of patients with PHPT is therefore of importance. The aim of this study was to determine PHPT prevalence among postmenopausal women with a distal forearm fracture.

Methods

Recruitment was conducted in conjunction with the occurrence of a distal forearm fracture at Karolinska University Hospital. In total, 161 postmenopausal women were included in a cross-sectional study with repeated evaluations. Analyzes of serum calcium, ionized calcium, phosphate, parathyroid hormone (PTH), and vitamin D were performed. Diagnosis of PHPT was based on clinical evaluations and biochemical definitions of serum calcium and PTH in coherence with previous population prevalence reports.

Results

Mean age was 64.7 (9.5) years, serum calcium 2.33 (0.10) mmol/L, ionized calcium 1.25 (0.05) mmol/L and PTH 54 (26) ng/L. PTH was elevated in 32 (20%) women. In total, 11 (6.8%) women were diagnosed with PHPT; 6 with classical PHPT and 5 with mild PHPT. The prevalence of PHPT was significantly increased compared to the population prevalence of 3.4% (p = 0.022).

Conclusion

Screening postmenopausal women in conjunction with low-energy distal forearm fracture revealed a large number of women with parathyroid disturbance. Evaluation of parathyroid hormone and calcium status in this group of patients seems beneficial.

Anterior versus posterior fusion surgery in idiopathic scoliosis: a comparison of health-related quality of life and radiographic outcomes in Lenke 5C curves - results from the Swedish spine registry

PURPOSE

To compare health-related quality of life and radiographic outcomes in patients treated with either anterior or posterior fusion surgery for Lenke 5C type idiopathic scoliosis.

METHODS

We used data from the Swedish spine registry and identified 59 patients with idiopathic scoliosis treated with fusion for Lenke 5C type curves; 27 patients underwent anterior surgery and 32 underwent posterior surgery. All patients had pre- and postoperative radiographic data and postoperative clinical data at a minimum of two years after surgery. Patient-reported outcomes measures included the Scoliosis Research Society (SRS)-22r, EuroQoL 5 dimensions 3 levels (EQ-5D-3L), EQ-visual analogue scale (VAS) and VAS for back pain. Radiographic assessment included measurement of the angle of the major curve, disc angulation below the lowest instrumented vertebra, curve flexibility, rate of curve correction, differences in sagittal parameters, number of fused vertebrae and length of fusion.

RESULTS

The mean age at surgery was 16 years in both groups. The mean follow-up time was 3.8 years. There were no significant differences in the SRS-22r score and EQ-5D-3L index at follow-up (all p ≥ 0.2). Postoperatively, both the anterior and posterior fusion group demonstrated a significant correction of the major curve (p ≤ 0.001) with no significant difference of the correction rate between the groups (p = 0.4). The posterior fusion group had shorter operative time (p < 0.001) and higher perioperative blood loss (p = 0.004) while the anterior group had lower number of fused vertebrae ( p< 0.001).

CONCLUSION

The type of surgical approach for Lenke 5C curves is not associated with differences in health-related quality of life, despite the lower number of fused vertebrae after anterior surgery.

LEVEL OF EVIDENCE

III.

Surgeons' behaviors and beliefs regarding placebo effects in surgery

Background and purpose - Emerging evidence from sham-controlled trials suggest that surgical treatment entails substantial non-specific treatment effects in addition to specific surgical effects. Yet, information on surgeons' actual behaviors and beliefs regarding non-specific treatment and placebo effects is scarce. We determined surgeons' clinical behaviors and attitudes regarding placebo effects.Methods - A national online survey was developed in collaboration with surgeons and administered via an electronic link.Results - All surgical clinics in Sweden were approached and 22% of surgeons participated (n = 105). Surgeons believed it was important for them to interact and build rapport with patients before surgery rather than perform surgery on colleagues' patients (90%). They endorsed the importance of non-specific treatment effects in surgery generally (90%) and reported that they actively harness non-specific treatment effects (97%), including conveying confidence and calm (87%), building a positive interaction (75%), and making eye contact (72%). In communication regarding the likely outcomes of surgery, surgeons emphasized accurate scientific information of benefits/risks (90%) and complete honesty (63%). A majority felt that the improvement after some currently performed surgical procedures might be entirely explained by placebo effects (78%). Surgeons saw benefits with sham-controlled surgery trials, nevertheless, they were reluctant to refer patients to sham controlled trials (46%).Interpretation - Surgeons believe that their words and behaviors are important components of their professional competence. Surgeons saw the patient-physician relationship, transparency, and honesty as critical. Understanding the non-specific components of surgery has the potential to improve the way surgical treatment is delivered and lead to better patient outcomes.

Predictors of persistent postoperative pain after surgery for idiopathic scoliosis

PURPOSE

To identify factors contributing to persistent postoperative pain in patients treated surgically for idiopathic scoliosis.

METHODS

In total, 280 patients aged ten through 25 years at surgery, were identified in the Swedish Spine registry; all having preoperative and postoperative visual analogue scale (VAS) for back pain scores. The patients were divided into a high and low postoperative pain group based on the reported postoperative VAS for back pain scores (by using 45 mm on the 0 mm to 100 mm VAS scale as a cut-off). The patient-reported questionnaire included VAS for back pain, the 3-level version of EuroQol 5-dimensional (EQ-5D-3L) instrument, the EuroQol VAS (EQ-VAS) and the Scoliosis Research Society 22r instrument (SRS-22r). Predictors of postoperative back pain were searched in the preoperative data.

RESULTS

The 67 (24%) patients that reported high postoperative VAS back pain (> 45 mm) also reported lower postoperative EQ-5D-3L, EQ-VAS and SRS-22r than patients with low postoperative VAS back pain (all p < 0.001). Two preoperative variables were independently associated with postoperative pain; each millimetre increase in preoperative VAS back pain (on the 0 mm to 100 mm scale) was associated with a higher risk of being in the high postoperative back pain group (odds ratio (OR) 1.03; 95% confidence interval (CI) 1.02 to 1.05) and each 1 point decrease on the preoperative SRS-22r mental health (scale from 1 to 5) was associated with a higher risk of being in the high postoperative back pain group (OR 1.68; 95% CI 1.03 to 2.73).

CONCLUSION

High preoperative back pain and low preoperative mental health are independent predictors of back pain after surgery for idiopathic scoliosis.

LEVEL OF EVIDENCE

III.

PReventing Idiopathic SCOliosis PROgression (PRISCOPRO): A protocol for a quadruple-blinded, randomized controlled trial comparing 3D designed Boston brace to standard Boston brace

INTRODUCTION

Idiopathic scoliosis is the most common spinal deformity in children. Treatment strategies aim to halt progression of the curve. Patients are treated mainly with thoracolumbosacral orthosis (TLSO) if indicated. This form of brace treatment has been shown to be cumbersome and tough on growing individuals. However, computer aided design and manufactured (CAD/CAM) braces might increase comfortability and ultimately outcome if compliance is improved. In a multicenter, randomized controlled trial, we aim to compare CAD/CAM designed Boston 3D-brace to standard Boston brace.

METHODS

Subjects: 170 previously untreated and skeletally immature children diagnosed with idiopathic scoliosis, aged 9-17 years of age (curve magnitude Cobb 25-40 degrees) will be included. Interventions: Both groups will receive a physical activity prescription according to the World Health Organization recommendations. Randomization will be performed 1:1 to a 3D CAD/CAM designed Boston 3D-brace or a standard Boston brace, both with prescribed daily wear time of 20 hours. Outcome: The subjects will participate in the study until curve progression or until skeletal maturity. The primary outcome variable is failure of treatment, defined as progression of the Cobb angle more than 6 degrees compared to the baseline x-ray. The progression is confirmed if seen on two consecutive standing spinal x-rays. Radiographs will be taken at each six-month follow-up. Secondary outcome measures include patient and clinical reported outcomes, including number of individuals requiring surgical intervention.

DISCUSSION

This study will show if efficacy in brace treatment can be improved with new brace designs.

TRIAL REGISTRATION

The protocol has been registered on ClinicalTrials.gov, identifier: NCT04805437.

The heritability of coronal and sagittal phenotype in idiopathic scoliosis: a report of 12 monozygotic twin pairs

PURPOSE

One of the pathways through which genetics may act in the causation of idiopathic scoliosis is inheritance of a specific sagittal profile that predisposes for its development. In this study, coronal and sagittal parameters were compared in an international collection of monozygotic twins with idiopathic scoliosis.

METHODS

Twelve monozygotic twin pairs who underwent biplanar radiography for idiopathic scoliosis were systematically identified in existing scoliosis databases in The Netherlands, Sweden, and Denmark. On the first available radiographs, the coronal and sagittal curve parameters (Roussouly and Abelin types, thoracic kyphosis, lumbar lordosis and length of the posteriorly inclined segment) were determined.

RESULTS

In all 12 monozygotic twin pairs, both twins were affected by AIS. Four (33%) twin pairs had similar coronal and sagittal spinal phenotype, whereas two (17%) had different coronal phenotype and similar sagittal profiles, and six (50%) pairs had different coronal as well as sagittal phenotype.

CONCLUSIONS

Analysis of biplanar curve characteristics in monozygotic twins showed that all twin pairs were affected by idiopathic scoliosis. However, only 33% of the pairs had similar coronal and sagittal spinal phenotypes. Based on this limited dataset, the hypothesis can be formulated that besides genetic pre-disposition, the individual (inherited) sagittal profile plays a role in the development of different coronal curve type.

[Lumbar disc prosthesis, a high risk treatment for low back pain.]

When surgery is needed for chronic low back pain, replacement of the degenerated and potential pain generating disc with a prosthesis often gives good short-term pain relief. However, there is no evidence of the clinical superiority of prosthesis compared with other treatments. Disc prosthesis is associated with considerable risks of late severe complications, especially in revision surgery. The method has been suggested as a treatment for young active patients, which is highly questionable considering  the risk of late severe adverse events and complex revision surgery. Globally the method is declining and in many health care financing models it is not an approved treatment. In Sweden, the use of disc prosthesis is increasing.

Bone health in adolescents with idiopathic scoliosis

AIMS

Idiopathic scoliosis is the most common spinal deformity in adolescents and children. The aetiology of the disease remains unknown. Previous studies have shown a lower bone mineral density in individuals with idiopathic scoliosis, which may contribute to the causation. The aim of the present study was to compare bone health in adolescents with idiopathic scoliosis with controls.

METHODS

We included 78 adolescents with idiopathic scoliosis (57 female patients) at a mean age of 13.7 years (8.5 to 19.6) and 52 age- and sex-matched healthy controls (39 female patients) at a mean age of 13.8 years (9.1 to 17.6). Mean skeletal age, estimated according to the Tanner-Whitehouse 3 system (TW3), was 13.4 years (7.4 to 17.8) for those with idiopathic scoliosis, and 13.1 years (7.4 to 16.5) for the controls. Mean Cobb angle for those with idiopathic scoliosis was 29° (SD 11°). All individuals were scanned with dual energy x-ray absorptiometry (DXA) and peripheral quantitative CT (pQCT) of the left radius and tibia to assess bone density. Statistical analyses were performed with independent-samples t-test, the Mann-Whitney U test, and the chi-squared test.

RESULTS

Compared with controls, adolescents with idiopathic scoliosis had mean lower DXA values in the left femoral neck (0.94 g/cm² (SD 0.14) vs 1.00 g/cm² (SD 0.15)), left total hip (0.94 g/cm² (SD 0.14) vs 1.01 g/cm² (SD 0.17)), L1 to L4 (0.99 g/cm² (SD 0.15) vs 1.06 g/cm² (SD 0.17)) and distal radius (0.35 g/cm² (SD 0.07) vs 0.39 g/cm² (SD 0.08; all p ≤ 0.024), but not in the mid-radius (0.72 g/cm² vs 0.74 g/cm²; p = 0.198, independent t-test) and total body less head (1,559 g (SD 380) vs 1,649 g (SD 492; p = 0.0.247, independent t-test). Compared with controls, adolescents with idiopathic scoliosis had lower trabecular volume bone mineral density (BMD) on pQCT in the distal radius (184.7 mg/cm³ (SD 40.0) vs 201.7 mg/cm³ (SD 46.8); p = 0.029), but not in other parts of the radius or the tibia (p ≥ 0.062, Mann-Whitney U test).

CONCLUSION

In the present study, idiopathic scoliosis patients seemed to have lower BMD at central skeletal sites and less evident differences at peripheral skeletal sites when compared with controls. Cite this article: Bone Joint J 2020;102-B(2):268-272.

Augmented reality navigation with intraoperative 3D imaging vs fluoroscopy-assisted free-hand surgery for spine fixation surgery: a matched-control study comparing accuracy

This study aimed to compare screw placement accuracy and clinical aspects between Augmented Reality Surgical Navigation (ARSN) and free-hand (FH) technique. Twenty patients underwent spine surgery with screw placement using ARSN and were matched retrospectively to a cohort of 20 FH technique cases for comparison. All ARSN and FH cases were performed by the same surgeon. Matching was based on clinical diagnosis and similar proportions of screws placed in the thoracic and lumbosacral vertebrae in both groups. Accuracy of screw placement was assessed on postoperative scans according to the Gertzbein scale and grades 0 and 1 were considered accurate. Procedure time, blood loss and length of hospital stay, were collected as secondary endpoints. A total of 262 and 288 screws were assessed in the ARSN and FH groups, respectively. The share of clinically accurate screws was significantly higher in the ARSN vs FH group (93.9% vs 89.6%, p < 0.05). The proportion of screws placed without a cortical breach was twice as high in the ARSN group compared to the FH group (63.4% vs 30.6%, p < 0.0001). No statistical difference was observed for the secondary endpoints between both groups. This matched-control study demonstrated that ARSN provided higher screw placement accuracy compared to free-hand.

Long-term outcome of fusion for degenerative disc disease in the lumbar spine

Aims

Chronic low back pain due to degenerative disc disease is sometimes treated with fusion. We compared the outcome of three different fusion techniques in the Swedish Spine Register: noninstrumented posterolateral fusion (PLF), instrumented posterolateral fusion (IPLF), and interbody fusion (IBF).

Patients and Methods

A total of 2874 patients who were operated on at one or two lumbar levels were followed for a mean of 9.2 years (3.6 to 19.1) for any additional lumbar spine surgery. Patient-reported outcome data were available preoperatively (n = 2874) and at one year (n = 2274), two years (n = 1958), and a mean of 6.9 years (n = 1518) postoperatively and consisted of global assessment and visual analogue scales of leg and back pain, Oswestry Disability Index, EuroQol five-dimensional index, 36-Item Short-Form Health Survey, and satisfaction with treatment. Statistical analyses were performed with competing-risks proportional hazards regression or analysis of covariance, adjusted for baseline variables.

Results

The number of patients with additional surgery were 32/183 (17%) in the PLF group, 229/1256 (18%) in the IPLF group, and 439/1435 (31%) in the IBF group. With the PLF group as a reference, the hazard ratio for additional lumbar surgery was 1.16 (95% confidence interval (CI) 0.78 to 1.72) for the IPLF group and 2.13 (95% CI 1.45 to 3.12) for the IBF group. All patient-reported outcomes improved after surgery (p < 0.001) but were without statistically significant differences between the groups at the one-, two- and 6.9-year follow-ups (all p ≥ 0.12).

Conclusion

The addition of interbody fusion to posterolateral fusion was associated with a higher risk for additional surgery and showed no advantages in patient-reported outcome Cite this article: Bone Joint J 2019;101-B:1526–1533

Association Between Vitamin D, Frailty, and Progression of Frailty in Community-Dwelling Older Women

CONTEXT

Vitamin D (25OHD) is involved in many physiological functions that decline with age, contributing to frailty and increased risk for negative health outcomes. Whether 25OHD is a long-term risk marker for frailty over a longer time and whether it is consistent with advancing age is unclear.

OBJECTIVE

To investigate the association between 25OHD and frailty in older women followed for 10 years.

DESIGN AND SETTING

Prospective, population-based, cohort study in Malmö, Sweden.

PARTICIPANTS

Community-dwelling women, age 75 years (N = 1044) with reassessments at ages 80 (n = 715) and 85 (n = 382) years.

METHODS

Frailty was quantified using a 10-variable frailty index. Women were categorized as 25OHD insufficient (<50 nmol/L) or sufficient (≥50 nmol/L).

RESULTS

At ages 75 and 80 years, women with insufficient 25OHD were frailer than women with sufficient 25OHD (0.23 vs 0.18, P < 0.001; and 0.32 vs 0.25, P = 0.001, respectively). At age 80 years, 25OHD insufficiency was associated with subsequent frailty 5 years later (0.41 vs 0.32; P = 0.011). Accelerated progression of frailty was not associated with lower 25OHD levels, and 25OHD level >75 nmol/L was not additionally beneficial with regard to frailty. No association between 25OHD and frailty was observed at age 85 years. Within the frailty index, variables associated with 25OHD were related to muscle strength and function.

CONCLUSION

In this study, 25OHD insufficiency was associated with increased frailty in all but the oldest old. This study supports the value of maintaining sufficient 25OHD levels for healthy aging.

Lumbar disc herniation surgery in adolescents and young adults

Aims

The purpose of this study was to investigate the risk of additional surgery in the lumbar spine and to describe long-term changes in patient-reported outcomes after surgery for lumbar disc herniation in adolescents and young adults.

Patients and Methods

We conducted a retrospective study design on prospectively collected data from a national quality register. The 4537 patients were divided into two groups: adolescents (≤ 18 years old, n = 151) and young adults (19 to 39 years old, n = 4386). The risk of additional lumbar spine surgery was surveyed for a mean of 11.4 years (6.0 to 19.3) in all 4537 patients. Long-term patient-reported outcomes were available at a mean of 7.2 years (5.0 to 10.0) in up to 2716 patients and included satisfaction, global assessment for leg and back pain, Oswestry Disability Index, visual analogue scale for leg and back pain, EuroQol five-dimension questionnaire (EQ-5D), and 36-Item Short-Form Health Survey (SF-36) Mental Component Summary and Physical Component Summary scores. Statistical analyses were performed with Cox proportional hazard regression, chi-squared test, McNemar’s test, Welch–Satterthwaite t-test, and Wilcoxon’s signed-rank test.

Results

Any type of additional lumbar spine surgery was seen in 796 patients (18%). Surgery for lumbar disc herniation accounted for more than half of the additional surgeries. The risk of any additional surgery was 0.9 (95% confidence interval (CI) 0.6 to 1.4) and the risk of additional lumbar disc herniation surgery was 1.0 (0.6 to 1.7) in adolescents compared with the young adult group. Both age groups improved their patient-reported outcome data after surgery (all p < 0.001). Changes between short- (mean 1.9 years (1.0 to 2.0)) and long-term follow-up (mean 7.2 years (5.0 to 10.0)) were small.

Conclusion

The risk of any additional lumbar spine surgery and additional lumbar disc herniation surgery was similar in adolescents and young adults. All patient-reported outcomes improved from preoperative to the short-term follow-up, while no likely clinically important differences between the short- and long-term follow-up were seen within both groups. Cite this article: Bone Joint J 2019;101-B:1534–1541

Surgical Treatment of Degenerative Disk Disease in Three Scandinavian Countries: An International Register Study Based on Three Merged National Spine Registers

STUDY DESIGN

Observational study of prospectively collected data.

OBJECTIVES

Patients with chronic low back pain resistant to nonoperative treatment often face a poor prognosis for recovery. The aim of the current study was to compare the variation and outcome of surgical treatment of degenerative disc disease in the Scandinavian countries based on The International Consortium for Health Outcomes Measurement core spine data sets.

METHODS

Anonymized individual level data from 3 national registers were pooled into 1 database. At the time of surgery, the patient reports data on demographics, lifestyle topics, comorbidity, and data on health-related quality of life such as Oswestry Disability Index, Euro-Qol-5D, and back and leg pain scores. The surgeon records diagnosis, type of surgery performed, and complications. One-year follow-ups are obtained with questionnaires. Baseline and 1-year follow-up data were analyzed to expose any differences between the countries.

RESULTS

A total of 1893 patients were included. At 1-year follow-up, 1315 (72%) patients responded. There were statistically significant baseline differences in age, smoking, comorbidity, frequency of previous surgery and intensity of back and leg pain. Isolated fusion was the primary procedure in all the countries ranging from 84% in Denmark to 76% in Sweden. There was clinically relevant improvement in all outcome measures except leg pain.

CONCLUSIONS

In homogenous populations with similar health care systems the treatment traditions can vary considerably. Despite variations in preoperative variables, patient reported outcomes improve significantly and clinically relevant with surgical treatment.

Correction to: Bacteria: back pain, leg pain and Modic sign-a surgical multicenter comparative study

Unfortunately, the 5th author name was incorrectly published in the original paper. The complete correct name is given below.

A Novel Augmented-Reality-Based Surgical Navigation System for Spine Surgery in a Hybrid Operating Room: Design, Workflow, and Clinical Applications

BACKGROUND

Treatment of several spine disorders requires placement of pedicle screws. Detailed 3-dimensional (3D) anatomic information facilitates this process and improves accuracy.

OBJECTIVE

To present a workflow for a novel augmented-reality-based surgical navigation (ARSN) system installed in a hybrid operating room for anatomy visualization and instrument guidance during pedicle screw placement.

METHODS

The workflow includes surgical exposure, imaging, automatic creation of a 3D model, and pedicle screw path planning for instrument guidance during surgery as well as the actual screw placement, spinal fixation, and wound closure and intraoperative verification of the treatment results. Special focus was given to process integration and minimization of overhead time. Efforts were made to manage staff radiation exposure avoiding the need for lead aprons. Time was kept throughout the procedure and subdivided to reflect key steps. The navigation workflow was validated in a trial with 20 cases requiring pedicle screw placement (13/20 scoliosis).

RESULTS

Navigated interventions were performed with a median total time of 379 min per procedure (range 232-548 min for 4-24 implanted pedicle screws).

The total procedure time was subdivided into surgical exposure (28%), cone beam computed tomography imaging and 3D segmentation (2%), software planning (6%), navigated surgery for screw placement (17%) and non-navigated instrumentation, wound closure, etc (47%).

CONCLUSION

Intraoperative imaging and preparation for surgical navigation totaled 8% of the surgical time. Consequently, ARSN can routinely be used to perform highly accurate surgery potentially decreasing the risk for complications and revision surgery while minimizing radiation exposure to the staff.