Patient-perceived factors on treatment satisfaction in early onset scoliosis treated surgically with a minimum of ten years.

BACKGROUND: The prognosis of surgically treated subjects with early onset scoliosis (EOS) into adulthood has been lacking. We aimed to investigate the patients' perspectives on satisfaction with surgical treatment. METHODOLOGY: We included all surgical candidates with EOS who had undergone index spinal surgery for scoliosis correction between 2009 and 2013. The minimum duration of postoperative follow-up was 10 years at the time of survey completion. Three questionnaires were used in this study, comprising the revised Scoliosis Research Society questionnaire (SRS-22r), the Patient-Reported Outcomes Measurement Information System (PROMIS-29), and the World Health Organization Quality of Life (WHOQOL-BREF). Measures of treatment satisfaction were retrieved from SRS-22r. RESULTS: There were 29 participants who completed the survey, and thereby included in the study (i.e., a response rate of 43% and a dropout rate of 6%). Amongst them, 14, 11, and 4 individuals received posterior spinal fusion (PSF), magnetically controlled growing rods (MCGR), and traditional growing rods, respectively. The average duration after the index spinal surgery was 12.6 ± 2.2 years. Our findings revealed that self-image (across all treatment groups), sleep disruption (only in PSF), and social aspects (in both PSF and MCGR) were significantly worse when compared to the normative values. According to the multivariable linear regression model (R-square = 0.690, p < .001), an increase in SRS-22r mental health (p = .008) and PROMIS-29 social participation scores (p = .004) corresponded to 0.511 and 0.055 points increases in satisfaction. Every unit increase in PROMIS-29 fatigue (p = .043) and WHOQOL-BREF physical domain scores (p = .007) was in conjunction with 0.019 and 0.040 points decreases in satisfaction. SRS-22r self-image (p = .056) and WHOQOL-BREF environmental domain scores (p = .076) were included in the model but did not reach statistical significance. CONCLUSIONS: To improve the long term quality of life in surgical candidates with EOS, we demonstrated that mental health, social participation, fatigue, and physical health were significant factors associated with treatment satisfaction. Interestingly, demographic and radiographic parameters did not have a significant effect in our cohort.

Rib-on-Pelvis Deformity and Reported Pain in Neuromuscular Early-Onset Scoliosis.

BACKGROUND: Neuromuscular early-onset scoliosis (N-EOS) often presents with a long sweeping thoracolumbar scoliosis and pelvic obliquity. With severe pelvic obliquity, the ribs come into contact with the high side of the pelvis, termed rib-on-pelvis deformity (ROP). The goal of this study is to evaluate whether ROP is associated with reported pain and other health-related quality of life (HRQOL) measures. We hypothesize that ROP is associated with increased pain and negative HRQOL. METHODS: A multicenter international registry was queried for all nonambulatory patients with N-EOS from 2012 to 2022. Both surgical and nonsurgical patients were included. ROP was classified as a binary radiographic assessment of preoperative (surgical patients) and most recent follow-up (nonsurgical patients) upright radiographs. Reported pain and other HRQOL measures were assessed through the 24-Item Early Onset Scoliosis Questionnaire (EOSQ-24). Patients with nonupright radiographs or EOSQ-24 questionnaires and corresponding radiographs >4 months apart were excluded. RESULTS: Totally, 225 patients (8.4±3.1 y, 55% female) were included. The median major curve was 63.3 (IQR: 40.6 to 81.2) degrees and median pelvic obliquity was 15.5 degrees (IQR: 8.8 to 26.4). Eighty-three patients (37%) had ROP. ROP was associated with both frequency ( P <0.001) and severity ( P <0.001) of pain. ROP was associated with worse general health ( P =0.01), increased difficulty with vocalization ( P =0.02), increased frequency of shortness of breath ( P =0.002), and increased difficulty sitting upright ( P =0.04). Regarding overall EOSQ-24 domains, ROP was associated with worse general health, pain/discomfort, pulmonary function, and physical function ( P <0.01). In a subanalysis of 76 patients who underwent surgical intervention with at least 2 years of follow-up, patients with preoperative ROP experienced significantly greater improvements in both frequency ( P =0.004) and severity ( P =0.001) of pain than the patients without preoperative ROP at 2 years postoperatively. CONCLUSIONS: The overall incidence of ROP in N-EOS is about 37%. ROP is associated with greater pain and worse HRQOL through the EOSQ-24 questionnaire. Furthermore, these patients experienced a greater reduction in pain after surgery. Clinicians and parents must be aware that ROP is possibly a pain generator, but responds positively to surgical intervention. LEVEL OF EVIDENCE: Level III.

Increased lengthening frequency does not adversely affect the EOSQ scores in magnetically controlled growing rod surgeries in 133 subjects followed to final fusion.

PURPOSE: Magnetically Controlled Growing Rod (MCGR) allows frequent outpatient rod lengthening when treating Early Onset Scoliosis (EOS) patients. But there is lack of expert consensus on the optimal MCGR lengthening interval. EOS 24-Item Questionnaire (EOSQ) is validated for assessing health-related quality of life (HrQOL), family burden, and satisfaction. This is the first study assessing how MCGR lengthening intervals affects patient-perceived outcomes. METHODS: This is a multicentred cohort study with subjects recruited from 2012 to 2018 and followed till fusion. EOS subjects who underwent MCGR surgeries were grouped into high, medium or low lengthening interval subgroups based on 16 and 20 week cut-offs. Repeated measure analysis was performed on EOSQ's specified 12 domains. EOSQ results were taken: before index surgery, after index surgery, and prior to definitive treatment. Demographic, clinical and radiographic data were included in model adjustment. RESULTS: 133 subjects with mean follow-up of 3.5 (± 1.3) years were included, with 60 males and 73 females; 45 idiopathic, 23 congenital, 38 neuromuscular, and 27 syndromic patients. Mean Cobb angle at surgery was 67° (± 22°) with mean age of 8.3 (± 2.5) years. Between groups, clinical and radiographic parameters were comparable. Higher EOSQ scores in medium lengthening interval subgroup was present in fatigue (p = 0.019), emotion (p = 0.001), and parental impact (p = 0.049) domains, and overall score (p = 0.046). Trendline contrast between subgroups were present in general health (p = 0.006) and physical function (p = 0.025) domains. CONCLUSION: Patient-perceived outcome improvements appear similar between lengthening interval subgroups. All MCGR lengthening intervals were tolerated by patients and family, with no negative impact observed. LEVEL OF EVIDENCE: Prognostic Level III.

Management of Metastatic Spinal Disease - A Practical Approach.

STUDY DESIGN: Narrative review. OBJECTIVE: This review presents a comprehensive approach to the management of spinal metastases. METHODS: N/A. RESULTS: The wide spectrum of clinical presentation in spinal metastases necessitates a personalized approach to treatment planning. This includes a comprehensive diagnostic workup, oncological management, palliation of symptoms, and surgical intervention if appropriate. A systematic and multidisciplinary approach allows optimal shared decision making to reach an evidence-informed and value-congruent treatment plan for the patient. We highlight how advances in stereotactic body radiotherapy (SBRT) and separation surgery may be incorporated into clinical management from a spine surgeon's perspective. CONCLUSION: This review summarizes the approach and management of spinal metastases, its outcomes and complications.

Hypoxia-Preconditioned BMSC-Derived Exosomes Induce Mitophagy via the BNIP3-ANAX2 Axis to Alleviate Intervertebral Disc Degeneration.

Intervertebral disc degeneration (IVDD) is a chronic degenerative disease involving the aging and loss of proliferative capacity of nucleus pulposus cells (NPCs), processes heavily dependent on mitochondrial dynamics and autophagic flux. This study finds that the absence of BCL2/adenovirus E1B 19 kDa interacting protein 3 (BNIP3) is associated with senescence-related NPC degeneration, disrupting mitochondrial quality control. Bone marrow mesenchymal stem cells (BMSCs) have multidirectional differentiation potential and produce extracellular vesicles containing cellular activators. Therefore, in this study, BMSCs are induced under hypoxic stimulation to deliver BNIP3-rich extracellular vesicles to NPCs, thereby alleviating aging-associated mitochondrial autophagic flux, promoting damaged mitochondrial clearance, and restoring mitochondrial quality control. Mechanistically, BNIP3 is shown to interact with the membrane-bound protein annexin A2 (ANXA2), enabling the liberation of the transcription factor EB (TFEB) from the ANXA2-TFEB complex, promoting TFEB nuclear translocation, and regulating autophagy and lysosomal gene activation. Furthermore, a rat model of IVDD is established and verified the in vivo efficacy of the exosomes in repairing disc injuries, delaying NPC aging, and promoting extracellular matrix (ECM) synthesis. In summary, hypoxia-induced BMSC exosomes deliver BNIP3-rich vesicles to alleviate disc degeneration by activating the mitochondrial BNIP3/ANXA2/TFEB axis, providing a new target for IVDD treatment.

Mitochondrial-Targeted Metal-Phenolic Nanoparticles to Attenuate Intervertebral Disc Degeneration: Alleviating Oxidative Stress and Mitochondrial Dysfunction.

As intervertebral disc degeneration (IVDD) proceeds, the dysfunctional mitochondria disrupt the viability of nucleus pulposus cells, initiating the degradation of the extracellular matrix. To date, there is a lack of effective therapies targeting the mitochondria of nucleus pulposus cells. Here, we synthesized polygallic acid-manganese (PGA-Mn) nanoparticles via self-assembly polymerization of gallic acid in an aqueous medium and introduced a mitochondrial targeting peptide (TP04) onto the nanoparticles using a Schiff base linkage, resulting in PGA-Mn-TP04 nanoparticles. With a size smaller than 50 nm, PGA-Mn-TP04 possesses pH-buffering capacity, avoiding lysosomal confinement and selectively accumulating within mitochondria through electrostatic interactions. The rapid electron exchange between manganese ions and gallic acid enhances the redox capability of PGA-Mn-TP04, effectively reducing mitochondrial damage caused by mitochondrial reactive oxygen species. Moreover, PGA-Mn-TP04 restores mitochondrial function by facilitating the fusion of mitochondria and minimizing their fission, thereby sustaining the vitality of nucleus pulposus cells. In the rat IVDD model, PGA-Mn-TP04 maintained intervertebral disc height and nucleus pulposus tissue hydration. It offers a nonoperative treatment approach for IVDD and other skeletal muscle diseases resulting from mitochondrial dysfunction, presenting an alternative to traditional surgical interventions.

Treatment of Symptomatic Spinal Muscular Atrophy with Nusinersen: A Prospective Longitudinal Study on Scoliosis Progression.

Background: Nusinersen treatment has demonstrated efficacy in improving clinical outcomes for spinal muscular atrophy (SMA), yet its impact on scoliosis progression remains unclear. Objective: This study aimed to assess the progression of scoliosis in pediatric patients with SMA undergoing nusinersen treatment. Methods: In this prospective study, data were systematically collected from Hong Kong pediatric SMA patients receiving nusinersen between 2018 and 2023. All patients had longitudinal radiographic studies pre-nusinersen, and at half-yearly or yearly intervals during treatment based on the scoliosis severity. Motor function evaluations were conducted pre-nusinersen, and after starting treatment at 6- and 12-month intervals. Results: Twenty-three patients ((SMA type 1 (SMA1) = 8, SMA type 2 (SMA2) = 7, SMA type 3 (SMA3) = 8)) with a median age of 5.8 years (range: 0.4-17.5 years) at nusinersen initiation, and median follow-up duration of 3.4 years (range: 1.1-5.2 years) were included. During the study period, motor scores remained stable or improved in 83% of patients. However, scoliosis progressed across all subtypes, with mean annual progression rates of 5.2, 11.9, and 3.6 degrees in SMA1, SMA2, and SMA3 respectively. Patients initiating nusinersen between ages 5 and 11 years exhibited the most rapid progression, with rates of 11.8, 16.5, and 7.3 degrees per year in SMA1, SMA2, and SMA3 respectively. Positive correlations were observed between the difference in CHOP-INTEND score post-nusinersen and scoliosis progression in SMA1 (rs = 0.741, p = 0.041). Conversely, negative correlations were found between the difference in HFMSE score post-nusinersen and scoliosis progression in SMA2 (rs =-0.890, p = 0.012) and SMA3 (rs =-0.777, p = 0.028). Conclusions: This study reveals that nusinersen treatment in symptomatic pediatric SMA patients with motor improvement is linked to increased scoliosis progression in SMA1, whereas it is associated with decreased progression in SMA2 and SMA3. Age, baseline Cobb angle, and motor milestone improvement are influential factors in scoliosis progression.

Incidence of back pain from initial presentation to 3 years of follow-up in subjects with untreated adolescent idiopathic scoliosis.

BACKGROUND: Although back pain may be present in subjects with adolescent idiopathic scoliosis (AIS), its natural history is unknown. Therefore, this study evaluated the incidence of back pain in scoliotic adolescents longitudinally. METHODS: This retrospective analysis examined prospectively collected pain subscale data of the Scoliosis Research Society questionnaire between the initial presentation and up to 3 years of follow-up. Consecutive subjects with AIS aged 10-18 at baseline managed by observation within the study period were included. Study subjects with at least one time point of follow-up data were considered. Alternatively, a group with physiotherapy-treated was also included for comparison. RESULTS: We enrolled 428 subjects under observation. The incidence of back pain among study subjects was 14.7%, 18.8%, and 19.0% for the first year, second year, and third year of follow-up, respectively. Most experienced mild pain (1 out of 5 points) throughout the study. Neither incidence nor intensity of pain significantly differed between subjects under observation and received physiotherapy. Additionally, study subjects with a new onset of back pain had poorer function, self-image, and mental health scores than those without pain. CONCLUSION: We investigated the incidence of back pain longitudinally in subjects suffering from AIS. Further validation of the current results is warranted.

Impact of mental health components on the development of back pain in young adults with adolescent idiopathic scoliosis.

BACKGROUND: Back pain occurs commonly in adults and is multifactorial in nature. This study aimed to assess the prevalence and intensity of back pain during young adulthood in subjects with adolescent idiopathic scoliosis (AIS), as well as factors that may be associated with its prognosis. METHODS: Subjects with AIS aged 20-39 treated conservatively were included in this study. Patient-reported outcome measures in adulthood involved episodes of back pain, and scales of self-image, depression, anxiety, and stress. Additionally, pain, self-image, and mental health scores were retrieved at the first clinic consultation. Occurrence of back pain was defined as a numeric pain rating scale ≥ 6. RESULTS: 101 participants were enrolled. The prevalence of back pain in the lifetime, past 12 months, past 6 months, past 1 month, past 7 days, and past 24 h were 37%, 35%, 31%, 27%, 23%, and 20%, respectively. Male, self-image, and depression were significant associated factors for the development of back pain at all time points. Furthermore, the analyses of the initial presentation of participants have shown that participants with back pain in adulthood were characterised by poor self-image and mental health during their adolescence. CONCLUSION: The present study addressed the natural history of back pain in young adults with conservatively treated AIS. Psychological makeup has been shown to constitute the development of back pain and is strongly hinted as an early sign of having back pain in adulthood among subjects with AIS.

AO Spine Adult Spinal Deformity Patient Profile: A Paradigm Shift in Comprehensive Patient Evaluation in Order to Optimize Treatment and Improve Patient Care.

STUDY DESIGN: Modified Delphi study. OBJECTIVE: Adult spinal deformity (ASD) is an increasingly recognized condition, comprising a spectrum of pathologies considerably impacting patients' health and functional status. Patients present with a combination of pain, disability, comorbidities and radiological deformity. The study aims to propose a systematic approach of gathering information on the factors that drive decision-making by developing a patient profile. METHODS: The present study comprises of 3 parts. Part 1: Development of prototype of patient profile: The data from the Core Outcome Study on SCOlisis (COSSCO) by Scoliosis Research Society (SRS) was categorized into a conceptual framework. Part 2: Modified Delphi study: Items reaching >70% agreement were included in a 4 round iterative process with 51 panellists across the globe. Part 3: Pilot testing-feasibility: Content validity and usability were evaluated quantitatively. RESULTS: The profile consisted of 4 domains. 1. General health with demographics and comorbidities, 2.Spine-specific health with spine related health and neurological status, 3. Imaging with radiographic and MRI parameters and 4. Deformity type. Each domain consisted of 1 or 2 components with various factors and their measuring instruments. Profile was found to have an excellent content validity (I-CVIr 0.78-1.00; Ave-CVI 0.92) appropriateness, relevance and usefulness. CONCLUSIONS: The present study, is first to provide a universally applicable multimodal ASD patient profile to methodically describe patients. Physicians are encouraged to assess ASD patients holistically using this profile and not just based on radiographic findings.

An international survey of the structure and process of care for traumatic spinal cord injury in acute and rehabilitation facilities: lessons learned from a pilot study.

BACKGROUND: To describe the key findings and lessons learned from an international pilot study that surveyed spinal cord injury programs in acute and rehabilitation facilities to understand the status of spinal cord injury care. METHODS: An online survey with two questionnaires, a 74-item for acute care and a 51-item for rehabilitation, was used. A subset of survey items relevant to the themes of specialized care, timeliness, patient-centeredness, and evidence-based care were operationalized as structure or process indicators. Percentages of facilities reporting the structure or process to be present, and percentages of indicators met by each facility were calculated and reported separately for facilities from high-income countries (HIC) and from low and middle-income countries (LMIC) to identify "hard to meet" indicators defined as those met by less than two-thirds of facilities and to describe performance level. RESULTS: A total of 26 acute and 26 rehabilitation facilities from 25 countries participated in the study. The comparison of the facilities based on the country income level revealed three general observations: 1) some indicators were met equally well by both HIC and LMIC, such as 24-hour access to CT scanners in acute care and out-patient services at rehabilitation facilities; 2) some indicators were hard to meet for LMIC but not for HIC, such as having a multidisciplinary team for both acute and rehabilitation settings; and 3) some indicators were hard to meet by both HIC and LMIC, including having peer counselling programs. Variability was also observed for the same indicator between acute and rehabilitation facilities, and a wide range in the total number of indicators met among HIC facilities (acute 59-100%; rehabilitation 36-100%) and among LMIC facilities (acute: 41-82%; rehabilitation: 36-93%) was reported. CONCLUSIONS: Results from this international pilot study found that the participating acute and rehabilitation facilities on average adhered to 74% of the selected indicators, suggesting that the structure and processes to provide ideal traumatic spinal cord injury care were broadly available. Recruiting a representative sample of SCI facilities and incorporating regional attributes in future surveys will be helpful to examine factors affecting adherence to indicators.

Reliability of a three-dimensional spinal proprioception assessment for patients with adolescent idiopathic scoliosis.

PURPOSE: Although it is evident that some patients with adolescent idiopathic scoliosis (AIS) have proprioceptive deficit in peripheral joints, knowledge on the proprioceptive function of the deformed spine is limited. Nonetheless, spinal proprioception in AIS may be affected three-dimensionally, prior studies only focussed on evaluating peripheral proprioception in single plane. Therefore, this study aimed to develop a novel spinal proprioception assessment using three-dimensional motion analysis in patients with AIS. METHODS: Participants were included if they had a primary diagnosis of AIS who did not receive or failed conservative treatments. Three trunk repositioning tests involving flexion-extension, lateral-flexion, and axial-rotation were conducted. A three-dimensional kinematics of the trunk was used as the outcome measures. The proprioceptive acuity was quantified by the repositioning error. The intra-examiner and test-retest reliability were analysed by the intraclass correlation coefficient (ICC). RESULTS: Fifty-nine patients with AIS were recruited. Regarding the trunk flexion-extension test, the single measure ICC showed moderate reliability (0.46) and the average measures ICC demonstrated good reliability (0.72). As for the trunk lateral-flexion test, the reliability of single measure and average measures ICC was moderate (0.44) and good (0.70) reliability, respectively. For the trunk axial-rotation test, the single measure ICC indicated fair reliability (0.32), while the average measures ICC showed moderate reliability (0.59). CONCLUSION: This is the first study to evaluate the reliability of novel three-dimensional spinal proprioception assessments in patients with AIS. The trunk flexion-extension repositioning test may be preferable clinical test given its highest reliability.

Development and validation of the scoliosis misconception scale (SMS) for assessing level of misconception of patients with adolescent idiopathic scoliosis.

BACKGROUND: Little is known about patients' understanding of adolescent idiopathic scoliosis (AIS). This paper aims to develop and validate the Scoliosis Misconception Scale (SMS) and to explore patients' level of misconception about AIS. METHODS: A total of 195 patients who were newly referred with newly diagnosed AIS were recruited to assess their levels of misconception and psychological distress before and after their first consultation with a specialist. The 17-item SMS was administered to assess patients' level of misconception about AIS and the Kessler Psychological Distress Scale (K10) was used to measure their level of distress. RESULTS: According to the Item Response Theory, all items were within the acceptable range from -3.69 to 2.39 for difficulty parameters, which determined the difficulty of the scale, while most of the items were within the acceptable range from 0.11 to 1.54 for the discrimination parameters, which determined the rate at which the probability of endorsing a correct item changes given ability levels. Internal consistency by marginal reliability was 0.66. One-sample t test revealed that participants on average scored 6.79 (SD = 2.12) before the first clinic session and 6.45 (SD = 2.51) after the first clinic session, both significantly higher than 0 [t(75) = 27.86, p < .001; t(75) = 22.43, p < .001]. CONCLUSIONS: Despite a longstanding clinical model that functions well to treat AIS, most patients still have significant misconceptions about the condition. This highlights the necessity to assess patients' knowledge level of a medical condition and potential generalisability of misconception-distress link to the forefront across other illnesses.

Predictors of neurologic outcome after surgery for cervical ossification of the posterior longitudinal ligament differ based on myelopathy severity: a multicenter study.

OBJECTIVE: The purpose of this retrospective multicenter study was to compare prognostic factors for neurological recovery in patients undergoing surgery for cervical ossification of the posterior longitudinal ligament (OPLL) based on their presenting mild, moderate, or severe myelopathy. METHODS: The study included 372 consecutive patients with OPLL who underwent surgery for cervical myelopathy between 2006 and 2016 in East Asian countries with a high OPLL prevalence. Baseline and postoperative clinical outcomes were assessed using the Japanese Orthopaedic Association (JOA) myelopathy score and recovery ratio. Radiographic assessment included occupying ratio, cervical range of motion, and sagittal alignment parameters. Patient myelopathy was classified as mild, moderate, or severe based on the preoperative JOA score. Linear and multivariate regression analyses were performed to identify patient and surgical factors associated with neurological recovery stratified by baseline myelopathy severity. RESULTS: The mean follow-up period was 45.4 months (range 25-140 months). The mean preoperative and postoperative JOA scores and recovery ratios for the total cohort were 11.7 ± 3.0, 14.5 ± 2.7, and 55.2% ± 39.3%, respectively. In patients with mild myelopathy, only age and diabetes correlated with recovery. In patients with moderate to severe myelopathy, older age and preoperative increased signal intensity on T2-weighted imaging were significantly correlated with a lower likelihood of recovery, while female sex and anterior decompression with fusion (ADF) were associated with better recovery. CONCLUSIONS: Various patient and surgical factors are correlated with likelihood of neurological recovery after surgical treatment for cervical OPLL, depending on the severity of presenting myelopathy. Older age, male sex, intramedullary high signal intensity, and posterior decompression are associated with less myelopathy improvement in patients with worse baseline function. Therefore, myelopathy-specific preoperative counseling regarding prognosis for postoperative long-term neurological improvement should include consideration of these individual and surgical factors.

Toward the Development of a Comprehensive Clinically Oriented Patient Profile: A Systematic Review of the Purpose, Characteristic, and Methodological Quality of Classification Systems of Adult Spinal Deformity.

BACKGROUND: Existing adult spinal deformity (ASD) classification systems are based on radiological parameters but management of ASD patients requires a holistic approach. A comprehensive clinically oriented patient profile and classification of ASD that can guide decision-making and correlate with patient outcomes is lacking. OBJECTIVE: To perform a systematic review to determine the purpose, characteristic, and methodological quality of classification systems currently used in ASD. METHODS: A systematic literature search was conducted in MEDLINE, EMBASE, CINAHL, and Web of Science for literature published between January 2000 and October 2018. From the included studies, list of classification systems, their methodological measurement properties, and correlation with treatment outcomes were analyzed. RESULTS: Out of 4470 screened references, 163 were included, and 54 different classification systems for ASD were identified. The most commonly used was the Scoliosis Research Society-Schwab classification system. A total of 35 classifications were based on radiological parameters, and no correlation was found between any classification system levels with patient-related outcomes. Limited evidence of limited quality was available on methodological quality of the classification systems. For studies that reported the data, intraobserver and interobserver reliability were good (kappa = 0.8). CONCLUSION: This systematic literature search revealed that current classification systems in clinical use neither include a comprehensive set of dimensions relevant to decision-making nor did they correlate with outcomes. A classification system comprising a core set of patient-related, radiological, and etiological characteristics relevant to the management of ASD is needed.

Are Higher Global Alignment and Proportion Scores Associated With Increased Risks of Mechanical Complications After Adult Spinal Deformity Surgery? An External Validation.

BACKGROUND: The Global Alignment and Proportion (GAP) score, based on pelvic incidence-based proportional parameters, was recently developed to predict mechanical complications after surgery for spinal deformities in adults. However, this score has not been validated in an independent external dataset. QUESTIONS/PURPOSES: After adult spinal deformity surgery, is a higher GAP score associated with (1) an increased risk of mechanical complications, defined as rod fractures, implant-related complications, proximal or distal junctional kyphosis or failure; (2) a higher likelihood of undergoing revision surgery to treat a mechanical complication; and (3) is a lower (more proportioned) GAP score category associated with better validated outcomes scores using the Oswestry Disability Index (ODI), Scoliosis Research Society-22 (SRS-22) and the Short Form-36 questionnaires? METHODS: A total of 272 patients who had undergone corrective surgeries for complex spinal deformities were enrolled in the Scoli-RISK-1 prospective trial. Patients were included in this secondary analysis if they fulfilled the original inclusion criteria by Yilgor et al. From the original 272 patients, 14% (39) did not satisfy the radiographic inclusion criteria, the GAP score could not be calculated in 14% (37), and 24% (64) did not have radiographic assessment at postoperative 2 years, leaving 59% (159) for analysis in this review of data from the original trial. A total of 159 patients were included in this study,with a mean age of 58 ± 14 years at the time of surgery. Most patients were female (72%, 115 of 159), the mean number of levels involved in surgery was 12 ± 4, and three-column osteotomy was performed in 76% (120 of 159) of patients. The GAP score was calculated using parameters from early postoperative radiographs (between 3 and 12 weeks) including pelvic incidence, sacral slope, lumbar lordosis, lower arc lordosis and global tilt, which were independently obtained from a computer software based on centralized patient radiographs. The GAP score was categorized as proportional (scores of 0 to 2), moderately disproportional (scores of 3 to 6), or severely disproportional (scores higher than 7 to 13). Receiver operating characteristic area under curve (AUC) was used to assess associations between GAP score and risk of mechanical complications and risk of revision surgery. An AUC of 0.5 to 0.7 was classified as "no or low associative power", 0.7 to 0.9 as "moderate" and greater than 0.9 as "high". We analyzed differences in validated outcome scores between the GAP categories using Wilcoxon rank sum test. RESULTS: At a minimum of 2 years' follow-up, a higher GAP score was not associated with increased risks of mechanical complications (AUC = 0.60 [95% CI 0.50 to 0.70]). A higher GAP score was not associated with a higher likelihood of undergoing a revision surgery to treat a mechanical complication (AUC = 0.66 [95% 0.53 to 0.78]). However, a moderately disproportioned GAP score category was associated with better SF-36 physical component summary score (36 ± 10 versus 40 ± 11; p = 0.047), better SF-36 mental component summary score (46 ± 13 versus 51 ± 12; p = 0.01), better SRS-22 total score (3.4 ± 0.8 versus 3.7 ± 0.7, p = 0.02) and better ODI score (35 ± 21 versus 25 ± 20; p = 0.003) than severely disproportioned GAP score category. CONCLUSION: Based on the findings of this external validation study, we found that alignment targets based on the GAP score alone were not associated with increased risks of mechanical complications and mechanical revisions in patients with complex adult spinal disorders. Parameters not included in the original GAP score needed to be considered to reduce the likelihood of mechanical complications. LEVEL OF EVIDENCE: Level III, diagnostic study.

Brace Effectiveness Is Related to 3-Dimensional Plane Parameters in Patients with Adolescent Idiopathic Scoliosis.

BACKGROUND: Although scoliosis is a 3-dimensional (3D) deformity, little research has been performed on the use of 3D imaging in brace curve correction. The purpose of the present study was to determine the effect of axial-plane parameters on the outcomes of bracing with a thoracolumbosacral orthosis for adolescent idiopathic scoliosis. METHODS: This prospective longitudinal cohort study included patients with adolescent idiopathic scoliosis who fulfilled the criteria for bracing according to the Scoliosis Research Society, and was conducted from the time the patient began wearing the brace through a minimum follow-up of 2 years or until a surgical procedure was performed. Radiographs made with use of an EOS Imaging System were used to reconstruct 3D images of the spine at the pre-brace, immediate in-brace, 1-year in-brace, and latest follow-up out-of-brace stages. Univariate and multiple linear regressions were performed to determine the association between axial rotation correction and curve progression at the time of the latest follow-up. Logistic regressions were performed to model the probability of risk of progression. RESULTS: Fifty-three patients were enrolled, and 46 patients were included in the analysis. At the time of the latest follow-up, 30 patients did not experience curve progression and 16 patients had curve progression. There was no difference in baseline demographic characteristics between groups. For the transverse-plane parameters, there was a significant difference between non-progression and progression groups in pre-brace apical vertebral rotation (4.5° ± 11.2° compared with -2.4° ± 9.8°, respectively; p = 0.044) and in 1-year in-brace apical vertebral rotation correction velocity (2.0° ± 5.0°/year compared with -1.7° ± 4.4°/year, respectively; p = 0.016). Logistic regression analysis showed that pre-brace apical vertebral rotation (odds ratio, 1.063; 95% confidence interval, 1.000 to 1.131; p = 0.049) and 1-year in-brace apical vertebral rotation correction velocity (odds ratio, 1.19; 95% confidence interval, 1.021 to 1.38; p = 0.026) were associated with an increased risk of curve progression. There was no difference in Scoliosis Research Society 22-Item scores between patients who experienced curve progression and those who did not. CONCLUSIONS: In this prospective study, we demonstrated that axial-plane parameters and the correction of these parameters during bracing are related to the successful use of the brace. LEVEL OF EVIDENCE: Prognostic Level II. See Instructions for Authors for a complete description of levels of evidence.

A review of the manufacturing process and infection rate of 3D-printed models and guides sterilized by hydrogen peroxide plasma and utilized intra-operatively.

3D printing in the context of medical application can allow for visualization of patient-specific anatomy to facilitate surgical planning and execution. Intra-operative usage of models and guides allows for real time feedback but ensuring sterility is essential to prevent infection. The additive manufacturing process restricts options for sterilisation owing to temperature sensitivity of thermoplastics utilised for fabrication. Here, we review one of the largest single cohorts of 3D models and guides constructed from Acrylonitrile butadiene styrene (ABS) and utilized intra-operatively, following terminal sterilization with hydrogen peroxide plasma. We describe our work flow from initial software rendering to printing, sterilization, and on-table application with the objective of demonstrating that our process is safe and can be implemented elsewhere. Overall, 7% (8/114 patients) of patients developed a surgical site infection, which was not elevated in comparison to related studies utilizing traditional surgical methods. Prolonged operation time with an associated increase in surgical complexity was identified to be a risk factor for infection. Low temperature plasma-based sterilization depends upon sufficient permeation and contact with surfaces which are a particular challenge when our 3D-printouts contain diffusion-restricted luminal spaces as well as hollows. Application of printouts as guides for power tools may further expose these regions to sterile bodily tissues and result in generation of debris. With each printout being a bespoke medical device, it is important that the multidisciplinary team involved in production and application understand potential pitfalls to ensuring sterility as to minimize infection risk.

Impact of Thoracic Cage Dimension and Geometry on Cardiopulmonary Function in Patients With Congenital Scoliosis: A Prospective Study.

STUDY DESIGN: A prospective study of cardiopulmonary function in patients with congenital scoliosis (CS). OBJECTIVE: To investigate the relationship of thoracic cage deformity and exercise tolerance in CS patients. SUMMARY OF BACKGROUND DATA: Congenital thoracic scoliosis and chest deformity lead to restrictive pulmonary dysfunction and in some severe cases cause cardiopulmonary failure. However, it is still unknown the relationship between thoracic deformity and exercise performance. METHODS: Patients with congenital thoracic spinal deformity were included and had radiological assessment of thoracic cage, pulmonary function testing, and cardiopulmonary exercise testing. Thoracic dimension including height, width, and depth were measured and geometry parameters were calculated. Two-tailed Pearson and Spearman correlation test and linear regression analysis were performed to investigate correlation of radiographic parameters, pulmonary function, and physical capacity. RESULTS: Sixty patients (41 females and 19 males) were included, with an average age of 18.9 years. Patients with smaller thoracic height (P < 0.001) and width (P < 0.01) and larger depth (P < 0.05) had significantly worse static pulmonary function. In exercise testing, these patients showed significant tendency of ventilation insufficiency, including lower minute ventilation (P < 0.05), faster breathing frequency (P < 0.05), and smaller tidal volume (P < 0.01). Thoracic depth was negatively correlated to exercise capacity, reflected by work rate (P < 0.001), peak oxygen intake (P < 0.001), and heart rate (P = 0.043). Patients with abnormal thoracic geometry, especially a lower ratio of height to depth and a lower ratio of width to depth, have significantly worse static pulmonary function and exercise capacity (all P < 0.05). CONCLUSION: Decreasing thoracic height and width results in restrictive pulmonary dysfunction. Distortion and asymmetry of the thoracic cage are associated with abnormal breathing pattern and reduction of exercise capacity. LEVEL OF EVIDENCE: 3.

Selection of Lowest Instrumented Vertebra Using Fulcrum Bending Radiographs Achieved Shorter Fusion Safely Compared With the Last "Substantially" Touching Vertebra in Lenke Type 1A and 2A Curves.

STUDY DESIGN: Retrospective study with prospective radiographic data collection. OBJECTIVE: To compare fusion level determination criteria using the fulcrum bending radiograph (FBR) and the last substantially touched vertebra (STV) as the lowest instrumented vertebra (LIV) in the radiographic outcomes of correction surgery for Lenke 1A and 2A scoliosis patients with a minimum of 2-year follow-up. SUMMARY OF BACKGROUND DATA: The STV has been proposed as the LIV in Lenke 1A and 2A curves to avoid postoperative distal adding-on. However, the influence of the inherent flexibility of the curves on selecting the LIV in relation to the STV is not known. METHODS: A total of 65 consecutive Lenke 1A and 2A patients who underwent posterior selective thoracic fusion were included in this study with a minimum of 2-year follow-up. LIV determination was compared with the FBR and STV methods. The curve correction, trunk shift, radiographic shoulder height, list, and the incidence of distal adding-on were documented. RESULTS: Mean preoperative, postoperative, and final follow-up standing coronal Cobb angles of primary curves were 59.37°, 15.58°, and 16.62° respectively. Using the FBR to determine the LIV, STV was selected in 16 patients (25%), STV-1 in 34 (52%), STV-2 in 11 (17%), and STV-3 in three (5%). Fusion level difference between using FBR and STV method was statistically significantly larger (P = 0.019) in patients with more than 70% fulcrum flexibility (mean: 1.18 levels, range: 0-3 levels) than those with less than or equal to 70% flexibility (mean: 0.70 level, range: -1 to 3 levels). Mean fulcrum flexibility was 73.9% in patients who achieved a shorter fusion by FBR method and 66.3% in patients who did not achieve a shorter fusion. Adding-on was observed in three patients (4.6%). CONCLUSION: By considering the curve flexibility, LIV determination using FBR method achieved a shorter fusion than STV method in over 70% of Lenke 1A and 2A patients, while being safe and effective at 2-year follow-up. LEVEL OF EVIDENCE: 3.