The Optical Signatures of Stochastic Processes in Many-Body Exciton Scattering

We review our recent quantum stochastic model for spectroscopic lineshapes in the presence of a coevolving and nonstationary background population of excitations. Starting from a field theory description for interacting bosonic excitons, we derive a reduced model whereby optical excitons are coupled to an incoherent background via scattering as mediated by their screened Coulomb coupling. The Heisenberg equations of motion for the optical excitons are then driven by an auxiliary stochastic population variable, which we take to be the solution of an Ornstein-Uhlenbeck process. Here, we present an overview of the theoretical techniques we have developed as applied to predicting coherent nonlinear spectroscopic signals. We show how direct (Coulomb) and exchange coupling to the bath give rise to distinct spectral signatures and discuss mathematical limits on inverting spectral signatures to extract the background density of states. Expected final online publication date for the Annual Review of Physical Chemistry, Volume 74 is April 2023. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

Beware of open triradiate cartilage: 1 in 4 patients will lose > 10° of correction following posterior only fusion

PURPOSE

As 2-year follow-up may not be sufficient to assess the risk of curve progression following fusion in immature patients with adolescent idiopathic scoliosis (AIS), this study reports on 5-year outcomes of AIS patients, factoring in maturity and surgical approach, to determine whether immature patients are at risk of continued curve progression beyond 2 years.

METHODS

A multicenter database was reviewed for AIS patients who underwent spinal fusion with pedicle screw fixation and who had both 2 and 5-year follow-up. Radiographic and SRS-22 scores were compared between three groups: open triradiate cartilage-posterior fusion (OTRC-P), OTRC-combined anterior/posterior fusion (OTRC-APSF), and closed TRC (CTRC, matched to OTRC-P group).

RESULTS

142 subjects were included (67 OTRC-P, 8 OTRC-APSF, 67 CTRC). Main curve type (p = 0.592) and size (p = 0.117) were not different between groups at all timepoints. Compensatory curve size was similar at all timepoints for OTRC-P and CTRC, with a slight increase for OTRC-APSF from immediate postoperative to 5 years. At 5 years, OTRC-P had > 10° loss of correction in 25% of patients, which was greater than in the CTRC (6%) and OTRC-APSF (0%) groups (p = 0.002). No significant differences were found in loss of correction of the compensatory curve or in SRS-22 scores between groups.

CONCLUSIONS

Compared to those with CTRC and those treated with anterior/posterior fusion, patients with OTRC treated with posterior fusion had an increased risk of main curve progression greater than 10°, with some continued loss of correction after 2 years. This did not appear to affect patient-reported outcomes.

Anterior Vertebral Body Tethering Compared with Posterior Spinal Fusion for Major Thoracic Curves

BACKGROUND

Anterior vertebral body tethering (AVBT) is an alternative to posterior spinal fusion (PSF) for the surgical treatment of scoliosis. The present study utilized a large, multicenter database and propensity matching to compare outcomes of AVBT to PSF in patients with idiopathic scoliosis.

METHODS

Patients with thoracic idiopathic scoliosis who underwent AVBT with a minimum 2-year follow-up retrospectively underwent 2 methods of propensity-guided matching to PSF patients from an idiopathic scoliosis registry. Radiographic, clinical, and Scoliosis Research Society 22-Item Questionnaire (SRS-22) data were compared preoperatively and at the ≥2-year follow-up.

RESULTS

A total of 237 AVBT patients were matched with 237 PSF patients. In the AVBT group, the mean age was 12.1 ± 1.6 years, the mean follow-up was 2.2 ± 0.5 years, 84% of patients were female, and 79% of patients had a Risser sign of 0 or 1, compared with 13.4 ± 1.4 years, 2.3 ± 0.5 years, 84% female, and 43% Risser 0 or 1 in the PSF group. The AVBT group was younger (p < 0.001), had a smaller mean thoracic curve preoperatively (48 ± 9°; range, 30° to 74°; compared with 53 ± 8°; range, 40° to 78° in the PSF group; p < 0.001), and had less initial correction (41% ± 16% correction to 28° ± 9° compared with 70% ± 11% correction to 16° ± 6° in the PSF group; p < 0.001). Thoracic deformity at the time of the latest follow-up was 27° ± 12° (range, 1° to 61°) for AVBT compared with 20° ± 7° (range, 3° to 42°) for PSF (p < 0.001). A total of 76% of AVBT patients had a thoracic curve of <35° at the latest follow-up compared with 97.4% of PSF patients (p < 0.001). A residual curve of >50° was present in 7 AVBT patients (3%), 3 of whom underwent subsequent PSF, and in 0 PSF patients (0%). Forty-six subsequent procedures were performed in 38 AVBT patients (16%), including 17 conversions to PSF and 16 revisions for excessive correction, compared with 4 revision procedures in 3 PSF patients (1.3%; p < 0.01). AVBT patients had lower median preoperative SRS-22 mental-health component scores (p < 0.01) and less improvement in the pain and self-image scores between preoperatively and the ≥2-year follow-up (p < 0.05). In the more strictly matched analysis (n = 108 each), 10% of patients in the AVBT group and 2% of patients in the PSF group required a subsequent surgical procedure.

CONCLUSIONS

At a mean follow-up of 2.2 years, 76% of thoracic idiopathic scoliosis patients who underwent AVBT had a residual curve of <35° compared with 97.4% of patients who underwent PSF. A total of 16% of cases in the AVBT group required a subsequent surgical procedure compared with 1.3% in the PSF group. An additional 4 cases (1.3%) in the AVBT group had a residual curve of >50° that may require revision or conversion to PSF.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Definitive fusion for scoliosis in late juvenile cerebral palsy patients is durable at 5 years postoperatively

PURPOSE

Given the challenges associated with managing progressive scoliosis in patients with cerebral palsy (CP), the purpose of this study was to evaluate deformity correction and HRQOL 5 years post-spinal fusion in CP patients who were skeletally immature at the time of surgical correction.

METHODS

CP patients who underwent definitive fusion before age 11 with minimum 5-years follow-up from a prospective, multicenter registry were included. Preoperative, initial postoperative, and 5-years radiographic data were collected. Preoperative and 5-years demographic, surgical data, complications, and CPCHILD outcome scores were analyzed. Repeated measures ANOVA with Bonferroni adjustment were used to analyze radiographic measures. Paired t test was utilized to compare outcomes. Significance was set at p = 0.05.

RESULTS

Twenty patients met inclusion-17 females, 3 males. The mean age was 9 (range 8-10) years. Eight-five percent had spastic CP with GMFCS Level V. Eighteen patients underwent posterior fusion; distal fixation was to the ilium in 80% and to L4-S1 in 20%. Significant correction of the primary curve (p ≤ 0.001) and pelvic obliquity (p ≤ 0.001) were obtained. From initial postoperative to 5-years follow-up there were no significant changes in major curve magnitude (p = 0.638), thoracic kyphosis (p = 0.09) or pelvic obliquity (p = 0.28). CPCHILD personal care, mobility, comfort, and total scores improved from preoperative to 5-years (p < 0.05). One patient needed a reoperation.

CONCLUSION

Surgical decision making for scoliosis in patients with CP can be difficult given the desire to maximize growth while minimizing adverse events. Performing a definitive fusion is a viable option that achieves good correction which remains stable 5 years postoperatively.

Three different techniques for pelvic fixation in the management of neuromuscular scoliosis in nonambulatory spastic cerebral palsy: A comparative study of Galveston Rod, iliac screw, and sacroiliac screw

OBJECTIVE

This study aimed to compare the clinical and radiographic results of three different pelvic fixation techniques, i.e., Galveston Rod, Iliac Screw, and Sacroiliac Screw, in managing neuromuscular scoliosis in nonambulatory children with spastic cerebral palsy (CP).

METHODS

This retrospective study included nonambulatory children aged < 18 years with neuromuscular scoliosis secondary to CP, undergoing a spinal fusion and pelvic fixation by either Galveston rod, iliac screw, or sacroiliac screw techniques. The primary outcome variable was to determine the stability of the major curve angle and pelvic obliquity over timeline intervals for each pelvic fixation tech nique. The two radiographic parameters were measured at five timeline intervals and were compared to define stability among the groups.

RESULTS

One hundred and one patients (54 females [53%]) with spastic nonambulatory CP met the inclusion criteria; the mean age at sur gery was 13.5±3.1 years. Mean follow-up intervals were first-year (12.9±1.5) and second-year (25.8±2.5). Forty-one patients had minimum five-year (81.5±23 months) postoperative follow-up. Groups were based on pelvic fixation techniques: 25 patients with the Galveston rod, 24 with the iliac screw, and 52 with the sacroiliac screw. Of the 41 patients with a minimum five-year follow-up, 10 had the Galveston rod, 11 had an iliac screw, and 20 had sacroiliac screw fixation. Gross Motor Function Classification System level, medical comorbidities, intra thecal baclofen pump, and vitamin D level were compared with each pelvic fixation technique (P > .05). Major curve angle parameters were measured at the five timelines as 70.5°±21.1°, 15.7°±13°, 15.7°±12°, 17.5°±12.7°, and 15.1°±9.6°, and pelvic obliquity as 14.8°±10.4°, 4.9°±4.2°, 5.7°±4.6°, 5°±4.4°, and 7.2°±4.4°, respectively. After the surgery, corrected major curve angle and pelvic obliquity showed no sta tistically significant difference between pelvic fixation techniques (P > .05) and remained stable over timeline intervals (P > .05). Fifteen patients had complications requiring additional surgery. The iliac screw group (nine patients) had the highest rate of complications.

CONCLUSION

All three pelvic fixation techniques can provide equivalent correction for major curve angle and pelvic obliquity in managing neuromuscular scoliosis in nonambulatory CP children. Pelvic obliquity after surgery may remain stable regardless of pelvic fixation type. A higher rate of postoperative complication can be encountered with the iliac screw.

LEVEL OF EVIDENCE

Level III, Retrospective Study.

Spontaneous Lumbar Curve Correction Following Vertebral Body Tethering of Main Thoracic Curves

BACKGROUND

Growth modulation through anterior vertebral body tethering (AVBT) has emerged as a fusionless option for the treatment of progressive scoliosis. When tethering the main thoracic curve, the compensatory thoracolumbar/lumbar curve must correct indirectly as a result. The present study evaluated the response of these lumbar curves following AVBT of the main thoracic curves.

METHODS

Patients who underwent thoracic AVBT and who had a minimum follow-up of 2 years were included. Magnitudes of the thoracic and lumbar curves were recorded preoperatively and at the first-erect and 2-year postoperative visits. Lumbar curves were further stratified according to their lumbar modifier (A, B, or C). Analysis of variance (ANOVA) and repeated-measures ANOVA were performed to compare correction rates, and the Pearson coefficient was utilized to determine the correlation between the tethered thoracic curve and uninstrumented lumbar curve magnitudes.

RESULTS

A total of 218 patients were included. Thoracic curve correction was 40% at the first-erect visit and 43% at 2 years (p = 0.012). Lumbar correction was 30%, 26%, and 18% at the first-erect visit (p < 0.001 for all compared with preoperatively) and minimally changed at 31%, 26%, and 24% at 2 years for lumbar modifiers A, B, and C, respectively. A total of 118 patients (54%) showed thoracic curve improvement between the first-erect and 2-year visits. In a subgroup analysis, these patients had a correction in lumbar curve magnitude from preoperatively to the first-erect visit of 30%, 22%, and 16% for lumbar modifiers A, B, C, respectively, that increased to 42%, 34%, and 31% at 2 years, with strong correlation to thoracic correction at 2-year follow-up (r = 0.557, p < 0.001).

CONCLUSIONS

Although there was immediate lumbar correction following AVBT of a main thoracic curve, further improvement following initial correction was only observed among patients with growth modulation of the thoracic curve. Considering all patients, the uninstrumented lumbar curve corrected 30% at 2 years and the instrumented thoracic curve corrected 40%. As indications for AVBT are refined, these data will provide insight into the response of the uninstrumented lumbar curve.

LEVEL OF EVIDENCE

Therapeutic Level III . See Instructions for Authors for a complete description of levels of evidence.

Preoperative factors associated with optimal outcomes of selective thoracic fusion at 5 years

PURPOSE

Prior work identified optimal outcomes at 2 years following selective thoracic fusion (STF) for adolescent idiopathic scoliosis (AIS) but it is unclear whether these published predictors represent what is required to achieve an optimal outcome with further time and potential growth. The purpose of this study was to determine the preoperative factors associated with optimal outcome of STF for AIS at 5 years.

METHODS

Patients with primary thoracic AIS (Lenke 1-4C curves) who underwent a STF and had minimum 5 years of follow-up were included. Optimal postoperative outcomes for a STF included a deformity-flexibility quotient (DFQ) < 4, lumbar curve < 26°, lumbar correction > 37%, C7-CSVL < 2 cm, lumbar prominence < 5°, and trunk shift < 1.5 cm. These outcomes were used to determine whether adhering to published recommendations for STF increased the likelihood of obtaining an optimal outcome at 5 years, which included: preoperative lumbar curve < 45°, lumbar bend < 25°, apical vertebral translation ratio > 1.2, and thoracic/thoracolumbar Cobb ratio > 1.2.

RESULTS

127 patients met inclusion. A preoperative lumbar curve < 45° was associated with an increased likelihood of achieving three of the optimal outcomes: DFQ < 4, lumbar curve < 26°, and lumbar prominence < 5°. Following the 25° bend rule resulted in two optimal outcomes, while Cobb ratio > 1.2 was only associated with one optimal outcome. AVT > 1.2 was not significantly associated with any optimal outcome measures.

CONCLUSION

This study found that at 5 years, performing a STF when there is a preoperative lumbar Cobb < 45° remained the best guideline for increasing the likelihood of an optimal outcome.

Prevalence and Risk Factors Associated With Pelvic Rod/Screw Radiographic Lucency Following Scoliosis Surgery in Spastic Cerebral Palsy: A Longitudinal Study

BACKGROUND

Radiographic lucency around a smooth pelvic rod (Galveston/unit rod technique) or sacroiliac/iliac screw following spinal fusion in children with nonambulatory spastic cerebral palsy (CP) has been described as a "windshield wiper" phenomenon. We evaluated demographics, radiographs, and complications in 101 cases from a single center to determine prevalence, risk factors, and complications associated with persistent radiographic lucency from 1 to 5 years following spinal fusion.

METHODS

Inclusion criteria were diagnosis of nonambulatory spastic quadriplegic CP [Gross Motor Function Classification System (GMFCS) IV-V], under 18 years of age, scoliosis treated by posterior fusion from upper thoracic to sacrum with pelvic fixation (Galveston rod, iliac screw, or sacroiliac screw), adequate radiographs (preoperative, immediate postoperative, first-year, and second-year), and minimum 5-year follow-up. We evaluated demographics, radiographic parameters, comorbidities, scoliosis curve type, type of pelvic screw/rod, use of off-set connector, screw width, associated with posterior column osteotomy and/or additional anterior spinal release concurrent with posterior spine fusion, and infection over the follow-up period. Specific attention was given to the area and shape of the radiographic lucency. The logistic regression analysis was performed for continuous and categorical variables to define risk factors ( P =0.05).

RESULTS

In 101 patients, data were collected at mean intervals of 1-year, 2-year, and >5-year follow-up and were 12.9±1.5, 25.8±2.5, and 81.5±23.0 months, respectively. Prevalence of pelvic rod/screw radiographic lucency was unchanged at 33%, 35%, and 24% at 1-year, 2-year, and >5-year follow-up, respectively, and radiographic parameters did not change ( P >0.05). Furthermore, no risk factors or complications were associated with radiographic lucency around pelvic rods/screws ( P >0.05).

CONCLUSION

In patients with spastic nonambulatory CP who had scoliosis treated with posterior spinal fusion from upper thorax to pelvis, the prevalence of pelvic rod/screw lucency is high. Persistent lucency >2 mm around pelvic implants is not clinically significant, does not warrant advanced imaging, or indicate a complication if stable over time and wider distally than proximally.

LEVEL OF EVIDENCE

Level III.

Longitudinal alterations in gamma-aminobutyric acid (GABAA) receptor availability over ∼ 1 year following traumatic brain injury

Longitudinal alterations of gamma-aminobutyric acid (GABA_A) receptor availability following traumatic brain injury have remained uncharacterized and may reflect changes in neuronal structure and function linked to cognitive recovery. We measured GABA_A receptor availability using the tracer [11C]flumazenil in nine adults with traumatic brain injury (3–6 months after injury, subacute scan) and in 20 non-brain-injured individuals. A subset of subjects with traumatic brain injury (n = 7) were scanned at a second chronic time-point, 7–13 months after their first scan; controls (n = 9) were scanned for a second time, 5–11 months after the first scan. After accounting for atrophy in subjects with traumatic brain injury, we find broad decreases in GABA_A receptor availability predominantly within the frontal lobes, striatum, and posterior-medial thalami; focal reductions were most pronounced in the right insula and anterior cingulate cortex (p < 0.05). Greater relative increase, compared to controls, in global GABA_A receptor availability appeared between subacute and chronic scans. At chronic scan (>1 year post-injury), we find increased pallidal receptor availability compared to controls. Conversely, receptor availability remained depressed across the frontal cortices. Longitudinal improvement in executive attention correlated with increases in receptor availability across bilateral fronto-parietal cortical regions and the anterior-lateral aspects of the thalami. The specific observations of persistent bi-frontal lobe reductions and bilateral pallidal elevation are consistent with the anterior forebrain mesocircuit hypothesis for recovery of consciousness following a wide range of brain injuries; our results provide novel correlative data in support of specific cellular mechanisms underlying persistent cognitive deficits. Collectively, these measurements support the use of [11C]flumazenil to track recovery of large-scale network function following brain injuries and measure response to therapeutics.

When successful, anterior vertebral body tethering (VBT) induces differential segmental growth of vertebrae: an in vivo study of 51 patients and 764 vertebrae

PURPOSE

This study aimed to determine (1) does vertebral body tethering (VBT) produce differential growth modulation in individual vertebrae in patients with idiopathic scoliosis, (2) does VBT change disc shape, and (3) does VBT affect total spine length?

METHODS

Patients with idiopathic scoliosis treated with VBT of the main thoracic curve and minimum 2-year follow-up were included. Vertebrae and discs were categorized as uninstrumented proximal thoracic, instrumented main thoracic, or uninstrumented thoracolumbar-lumbar. The left- and right-sided heights of each vertebra and disc were measured on subsequent radiographs to assess for differential growth. T1-T12 thoracic and T1-S1 thoracolumbar growth velocities were compared with standardized reference data.

RESULTS

Fifty-one patients (764 vertebrae and 807 discs) were analyzed. The average major curve magnitude improved from 46° ± 11° to 17° ± 11° at 2-year follow-up. Differential growth was observed in MT vertebrae, in which the left/concave side grew 2.0 ± 2.2 mm compared with 1.5 ± 2.3 mm on the right/convex (tethered) side (p < 0.001). Differential height changes were observed for all discs, but were most pronounced in instrumented MT discs, in which the right/convex sides decreased by an average of 1.2 mm each, compared with no significant height change on the left/concave side. Total spinal growth velocities were not significantly different from standard reference data.

CONCLUSION

Vertebral body tethering limits convex spinal growth as designed while permitting concave growth. Curve correction results from differential vertebral growth and decreased convex disc height. Overall spinal growth continues at the expected rate.

LEVEL OF EVIDENCE

Level IV case series.

Drought stress enhances the efficiency of floral dip method of Agrobacterium-mediated transformation in Arabidopsis thaliana

The Agrobacterium-mediated floral dip protocol is the most extensively used transformation method for a model plant Arabidopsis thaliana. Several useful methods for Agrobacterium tumefaciens-mediated transformations of Arabidopsis are existing, but they are time consuming and with low transformation efficiency. Here, we developed a transgenic Arabidopsis lines TET12p::TET12-RFP in a short period of time and enhanced transformation efficiency by using a modified transformation method by applying drought stress after floral dip. In this protocol, Agrobacterium cells carrying TET12p::TET12-RFP recombinant vectors were resuspended in a solution of 5% sucrose, 0.05% (v/v) silwet L-77 to transform female gametes of developing Arabidopsis inflorescences. Treated Arabidopsis were then applied with different levels of drought stresses to stimulate plants for the utilization of maximum plant energy in seed maturation process. The applied stresses achieved the fast maturation of already treated inflorescences while stopped the growing of newly arising untreated inflorescence, thus decreased the chances of wrong collection of untransformed seeds. Consequently, the collected seeds were mostly transgenic with a transformation frequency of at least 10%, thus the screening for positive transformants selection was more advantageous on a selective medium as compared to a classical floral dip method. Within 2-3 months, two hundred of individual transgenic plants were produced from just 10 infiltrated plants. This study concludes that application of drought stresses in a specific stage of plant is a beneficial strategy for achieving the transgenic Arabidopsis in a short period of time with high transformation efficiency.

Endoscopic findings among geriatric patients with anaemia and chronic kidney disease at a tertiary teaching hospital in Malaysia

BACKGROUND

Older people with chronic kidney disease (CKD) may be anaemic due to various reasons, and they are vulnerable to various consequences. One of the most important causes of anaemia to be recognised in this population is gastrointestinal loss. The outcome can be improved by early detection, careful investigation, and suitable therapies. There is currently no standardised grading scale or reliable indicators to assist clinicians on handling gastrointestinal workup in elderly CKD patients who are anaemic.

METHODS

A cross-sectional study of 171 people aged 60 and over who had CKD (stages 3-5), including those on Renal Replacement Therapy (RRT) and anaemia. Using oesophagogastroduodenoscopy, colonoscopy, and double balloon endoscopy, we analysed the endoscopic findings and calculated the prevalence of anaemia secondary to gastrointestinal disease. Haemoglobin, mean corpuscular volume (MCV), mean corpuscular haemoglobin concentration (MCHC), mean cell haemoglobin (MCH), iron panels, and immuno-faecal occult blood test (iFOBT) were evaluated to predict the diagnostic utility of each parameter in relation to gastrointestinal disorder in the elderly CKD population.

RESULTS

Abnormal endoscopic findings were obtained by upper and lower endoscopy in 98 individuals (57.3%). Upper endoscopy revealed the most prevalent lesions to be gastritis, gastric ulcer, and duodenal ulcer. The upper and lower endoscopies revealed a total of 14.0% malignant and pre-malignant lesions. T-test and receiver-operating characteristic (ROC) curve were performed on all haematological parameters and iron panels. Low ferritin level (less than 100 ng/mL) and combination with low transferrin saturation (less than 20%) have a significant p value less than 0.05. None of these variables had a significant area under the curve (AUC) of more than 0.75.

CONCLUSION

Positive endoscopic findings of anaemia are common in the older population at various stages of CKD, regardless of age, gender, or race. Malignant and premalignant lesions are not uncommon in older CKD patients. In the older CKD population, GI inflammation and ulceration are common lesions. Serum ferritin and TSAT levels are useful indicators of GI disorder in this population. Endoscopic evaluation as part of anaemia workup in the older people with CKD should not be ruled out.

Surgical outcomes of severe spinal deformities exceeding 100° or treated by vertebral column resection (VCR). Does implant density matter?: an observational study of deformity groupings

STUDY DESIGN

Prospective multicenter international observational study.

OBJECTIVE

To investigate the effect of implant density on clinical outcomes in complex pediatric spine reconstruction. Implant density in spine deformity surgery has been a subject of much debate with some authors advocating higher density for better correction. Few studies have looked at the effect of implant density on severe curves > 100 deg or treated with vertebral column resection (VCR).

METHODS

250/311 pts with 2-year f/u enrolled in the FOX pediatric database from 17 international sites were queried for the impact of implant density and surgical outcomes. Patients were grouped into three implant density categories for comparative analysis Group 1 (density ≤ 1), Group 2 (1 < density < 1.5) and Group 3 (density; 1.5-2).

RESULTS

250 pts: 47 (Grp1)/99 (Grp2) /104 (Grp3); Pre-op age and etiology and curve types were similar in all groups, but body mass index (BMI) was higher in Grp3. Grps 1 and 2 had significantly higher sagittal deformity angular ratio (S-DAR) compared to Grp 3 (p < 0.001). Pre-op Halo Gravity Traction (HGT) was used in 55.3%/44.4%/31.7%, p = 0.017; Grp1/Grp2/Grp3, respectively. Average duration of surgery (min) was higher in Grp3 relative to Grp1 only: 352.5/456.5/515.0, p = 0.0029. Blood loss was similar in all Grps. Rate of VCR, PSO and SPO was similar in all Grps. Pre-op Coronal Cobb avg 96.1/83.6/88.6, p = 0.2342, attained similar correction after HGT (24.6%/27.2%/23.2%, p = 0.4864. Coronal Cobb corrections at 2-year follow-up (FU) were (37.1%/40.3%/53.5%, p = 0.0004). Pre-op sagittal Cobb was (105.4/101.9/75.9, p < 0.01.), achieved similar %correction in HGT (19.1%/22.3%/22.5%, p = 0.6851) and at 2-year FU (39.6%/41.4%/29.8%, p = 0.1916). After adjusting for C-DAR, S-DAR, pre-op coronal and sagittal Cobb, etiology, curve types, age, BMI and number of rods in multivariate analysis, the odds of developing post-operative implant complication was 11 times greater in group 1 compared to group 3 (OR = 11.17,95% CI 2.34-53.32). There was significant improvement in SRS scores in all Grps at 2-year FU.

CONCLUSION

Although higher implant density was observed to be associated with greater curve correction and lower rates of post-operative implant-related complication and revision in heterogeneous case groups, the results may not imply causality of implant density on the outcomes in severe pediatric spine reconstruction.

The Role of Satisfaction Surveys: Offering an Enhanced Patient Experience for Optimum Outcomes in the Pediatric Orthopaedic Practice

As we navigate to provide the best patient care and outcomes, the patient experience has shown to be a driver that improves quality. Patient experience surveys are the primary means of measuring the perception of the care received. Positive patient experience has been linked to better patient compliance, decreased health care costs, decreased liability, and improved outcomes. Physician wellbeing and improved job satisfaction is a recognized additional benefit. Strategies have been developed to achieve these goals, enhance our practice and improve our work satisfaction and the patient experience.

Treatment of Early-onset Scoliosis: Similar Outcomes Despite Different Etiologic Subtypes in Traditional Growing Rod Graduates

BACKGROUND

It is unclear whether traditional growing rod (TGR) treatment outcomes vary by early-onset scoliosis (EOS) subtype. The goal of this study was to compare radiographic outcomes and complications of TGR treatment by EOS subtype.

METHODS

We queried an international database of EOS patients from 20 centers to identify "graduates" who had (1) undergone primary TGR treatment from 1993 to 2014; (2) completed TGR treatment; and (3) had an uneventful clinical examination within 6 months after completion of TGR treatment with no anticipated further intervention. We included 202 patients in 4 etiologic subgroups: neuromuscular (n=65), syndromic (n=57), idiopathic (n=52), and congenital (n=28). Mean age at surgery was 7.1 years (range, 1.6 to 14.9 y); mean duration of follow-up was 8 years (range, 2 to 18.6 y). The groups did not differ by mean age, body mass index, sex, number of lengthenings, or duration of follow-up. The following preoperative differences were significant: (1) greater mean major curve in the neuromuscular versus idiopathic subgroup; (2) shorter spinal height (T1-S1) in the congenital versus idiopathic subgroup; and (3) smaller proportion of ambulatory patients in the neuromuscular subgroup versus all other subgroups.

RESULTS

We found no significant differences among subgroups in mean major curve correction or changes in thoracic height (T1-T12), spinal height, or global kyphosis at any point. Rates of deep surgical site infection, implant-related complications, and neurological complications were not different among subgroups. The medical complication rate was significantly lower in the idiopathic group compared with the other groups.

CONCLUSIONS

Major curve correction and spinal and thoracic height increases did not differ significantly at any point by EOS subtype. Rates of deep surgical site infection, implant-related complications, and neurological complications did not differ by subtype. Except for the lower rate of medical complications in the idiopathic group, our findings suggest that, after TGR treatment, patients can expect similar outcomes regardless of their EOS subtype.

LEVEL OF EVIDENCE

Level III, therapeutic.

What is the effect of intraoperative traction on correction of adolescent idiopathic scoliosis (AIS)?

PURPOSE

Determine the efficacy of intraoperative traction (IOT) on curve correction in AIS.

METHODS

A prospective, multicenter, longitudinal database identified patients with major thoracic AIS (Lenke 1-4) treated with surgery using IOT and follow-up of 2 years. These cases were matched to comparable cases treated without traction (non-IOT). All patients were treated with single-stage posterior only surgery with pedicle screw constructs. Perioperative, radiographic and clinical outcome data at 2 years post-op were compared between the groups.

RESULTS

104 cases treated with IOT were matched to 104 treated without IOT. Operating room time was significantly greater in the IOT group (339 vs. 306 min, p =  < 0.001). Neuromonitoring alerts were more frequent in the IOT group (23% vs. 5%, p < 0.001). There were no postoperative neurological deficits in either group. The IOT group showed significantly greater MT curve correction (IOT 71% vs. non-IOT 66.7%, p < 0.003), with the effect most pronounced in curves > 70° (IOT 72% vs. non-IOT 64%, p = 0.04). IOT was associated with a significant reduction in 2D T5-T12 kyphosis measurements (IOT - 6.5° vs non-IOT + 0.48°, p < 0.001), yet significant improvements in estimated 3D thoracic kyphosis were made in both groups, with the non-IOT group making greater improvement when compared to the IOT group (IOT + 18.1° vs. non-IOT + 22.3° vs., p = 0.008).

CONCLUSIONS

IOT is associated with modestly enhanced coronal deformity correction. Surgeons should be aware of the increased rates of neuromonitoring alerts when using this technique and its affect on the sagittal profile. Given this IOT may be best suited to larger curves.

LEVEL OF EVIDENCE

3.

Early and late hospital readmissions in adolescent idiopathic scoliosis

STUDY DESIGN

Retrospective review of a prospectively collected multicenter database.

OBJECTIVES

To identify risk factors for early and late readmission of surgically treated patients with adolescent idiopathic scoliosis (AIS). Specific risk factors associated with readmission in patients with AIS remain poorly understood.

METHODS

Patients with AIS who were operatively treated from 19 centers specializing in the treatment of pediatric spinal deformity were studied. Data from a minimum 2 years of clinical follow-up and any readmission were available for analysis. Characteristics of patients with no readmission, early readmission (< 90 days), and late readmission (> 90 days) were evaluated. Both univariate and multivariate analyses of risk factors for readmission were performed.

RESULTS

2049 patients were included in our cohort, with 1.6% requiring early readmission and 3.3% late readmission. In the multivariate analysis, greater preoperative coronal imbalance was associated with early readmission. Longer operative time was associated with late readmission. Finally, greater preoperative pain (SRS-22 pain scale) was associated with both early and late readmission. GI complications accounted for a higher proportion of early readmissions than previously reported in the literature.

CONCLUSIONS

Preoperative counseling of patients with higher levels of pain and coronal imbalance and the implementation of a thorough postoperative bowel regimen may help optimize patient outcomes.

LEVEL OF EVIDENCE

3.

Association of clinical factors and recent anticancer therapy with COVID-19 severity among patients with cancer: a report from the COVID-19 and Cancer Consortium

BACKGROUND

Patients with cancer may be at high risk of adverse outcomes from severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. We analyzed a cohort of patients with cancer and coronavirus 2019 (COVID-19) reported to the COVID-19 and Cancer Consortium (CCC19) to identify prognostic clinical factors, including laboratory measurements and anticancer therapies.

PATIENTS AND METHODS

Patients with active or historical cancer and a laboratory-confirmed SARS-CoV-2 diagnosis recorded between 17 March and 18 November 2020 were included. The primary outcome was COVID-19 severity measured on an ordinal scale (uncomplicated, hospitalized, admitted to intensive care unit, mechanically ventilated, died within 30 days). Multivariable regression models included demographics, cancer status, anticancer therapy and timing, COVID-19-directed therapies, and laboratory measurements (among hospitalized patients).

RESULTS

A total of 4966 patients were included (median age 66 years, 51% female, 50% non-Hispanic white); 2872 (58%) were hospitalized and 695 (14%) died; 61% had cancer that was present, diagnosed, or treated within the year prior to COVID-19 diagnosis. Older age, male sex, obesity, cardiovascular and pulmonary comorbidities, renal disease, diabetes mellitus, non-Hispanic black race, Hispanic ethnicity, worse Eastern Cooperative Oncology Group performance status, recent cytotoxic chemotherapy, and hematologic malignancy were associated with higher COVID-19 severity. Among hospitalized patients, low or high absolute lymphocyte count; high absolute neutrophil count; low platelet count; abnormal creatinine; troponin; lactate dehydrogenase; and C-reactive protein were associated with higher COVID-19 severity. Patients diagnosed early in the COVID-19 pandemic (January-April 2020) had worse outcomes than those diagnosed later. Specific anticancer therapies (e.g. R-CHOP, platinum combined with etoposide, and DNA methyltransferase inhibitors) were associated with high 30-day all-cause mortality.

CONCLUSIONS

Clinical factors (e.g. older age, hematological malignancy, recent chemotherapy) and laboratory measurements were associated with poor outcomes among patients with cancer and COVID-19. Although further studies are needed, caution may be required in utilizing particular anticancer therapies.

CLINICAL TRIAL IDENTIFIER

NCT04354701.

What happens to the unfused upper thoracic curve after posterior spinal fusion for adolescent idiopathic scoliosis?

OBJECTIVE

Spontaneous lumbar curve correction after selective thoracic fusion in surgery for adolescent idiopathic scoliosis (AIS) is well described. However, only a few articles have described the course of the uninstrumented upper thoracic (UT) curve after fusion, and the majority involve a hybrid construct. In this study, the authors sought to determine the outcomes and associated factors of uninstrumented UT curves in patients with AIS.

METHODS

The authors retrospectively reviewed a prospectively collected multicenter AIS registry for all consecutive patients with Lenke type 1-4 curves with a 2-year minimum follow-up. UT curves were considered uninstrumented if the upper instrumented vertebra (UIV) did not extend above 1 level from the lower end vertebra of the UT curve. The authors defined progression as > 5°, and divided patients into two cohorts: those with improvement in the UT curve (IMP) and those without improvement in the UT curve (NO IMP). Radiographic, demographic, and Scoliosis Research Society (SRS)-22 survey outcome measures were compared using univariate analysis, and significant factors were compared using a multivariate regression model.

RESULTS

The study included 450 patients (370 females and 80 males). The UT curve self-corrected in 86% of patients (n = 385), there was no change in 14% (n = 65), and no patients worsened. Preoperatively, patients were similar with respect to Lenke classification (p = 0.44), age (p = 0.31), sex (p = 0.85), and Risser score (p = 0.14). The UT curves in the IMP group self-corrected from 24.7° ± 6.5° to 12.6° ± 5.9°, whereas in the NO IMP group UT curves remained the same, from 20.3° ± 5.8° to 18.5° ± 5.7°. In a multivariate analysis, preoperative main thoracic (MT) curve size (p = 0.004) and MT curve correction (p = 0.001) remained significant predictors of UT curve improvement. Greater correction of the MT curve and larger initial MT curve size were associated with greater likelihood of UT curve improvement.

CONCLUSIONS

Spontaneous UT curve correction occurred in the majority (86%) of unfused UT curves after MT curve correction in Lenke 1-4 curve types. The magnitude of preoperative MT curve size and postoperative MT curve correction were independent predictors of spontaneous UT curve correction.

Long-term Patient Perception Following Surgery for Adolescent Idiopathic Scoliosis if Dissatisfied at 2-year Follow-up

STUDY DESIGN

Longitudinal.

OBJECTIVES

To evaluate whether the rate of patients who report low health-related quality of life (HRQOL) scores at 2 years following surgical correction of adolescent idiopathic scoliosis (AIS) improves by 5 years postoperatively.

SUMMARY OF BACKGROUND DATA

HRQOL scores are dependent upon a number of factors and even in instances of good surgical correction of a spinal deformity, are not guaranteed to be high postoperatively. Understanding how a low HRQOL score varies over the postoperative period can help surgeons more effectively counsel patients and temper expectations.

METHODS

A multicenter database was reviewed for patients with both 2 and 5-year follow-up after spinal fusion and instrumentation for AIS. From a cohort of 916 patients, 52 patients with low HRQOL scores at their 2-year follow-up were identified and reevaluated at 5-year follow-up. A low HRQOL outcome was defined as having SRS-22 domain or total scores less than 2 standard deviations below the mean score. Reoperations were also evaluated to determine if they were associated with HRQOL scores.

RESULTS

Of those patients with low SRS-22 HRQOL scores at 2 years postoperatively, improvements were seen in all SRS-22 domains and total scores at the 5-year time point. The greatest change was seen in the satisfaction category where 41 patients showed improvement. The rate of reoperations during this period did not significantly impact patient-reported outcomes.

CONCLUSIONS

Having a low HRQOL score 2 years after surgery for AIS does not guarantee a low score 5 years after surgery. Promisingly, most patients demonstrate some improvement in all domains for patient-reported SRS-22 scores at 5-year compared to 2-year follow-up. Understanding the longer term postoperative evolution in patient-reported outcomes may help surgeons to effectively manage and counsel patients who are dissatisfied in the short term.Level of Evidence: 3.

What are parents willing to accept? A prospective study of risk tolerance in AIS surgery

INTRODUCTION

Surgical treatment of Adolescent Idiopathic Scoliosis (AIS) involves healthy individuals with spinal deformity. Parents are responsible for surgical consent on behalf of their children, a burden which causes trepidation and concern. Therefore, explanation of operative risk is a critical component of informed consent and parent decision-making. We set out to quantify parental risk aversion (RA).

METHODS

RA questionnaires were administered preoperatively to parents of 58 AIS patients undergoing spinal fusion (SF). RA is the likelihood of a parent to consent to their child's SF (1- least likely, 10- most) with increasing allotments of data about potential complications at each stage (S1-complication named, S2-explained, S3-incidence given, S4-all information). A statistically significant mean difference in answers for each stage was assessed using paired sample t test or Wilcoxon rank t test. Normality was assessed by performing Shapiro-Wilk test.

RESULTS

AIS patients (age 14.2 years, 85% female, major curve 61°) were included. Mean scores for each of the stages were 4.4 ± 3.1, 4.9 ± 3.1, 6.5 ± 3.0, 6.6 ± 3.0, respectively. Highest and lowest RA were reported for death and infection, respectively. The greatest increase in likelihood to proceed with surgery was seen after education on malposition of implants and on death, 2.6 and 2.5, respectively (p < 0.001). The lowest increase in likelihood to proceed with surgery was seen after education on infection, 1.5 (p < 0.001). For all complications, there was an increase in parent willingness to proceed after providing descriptions and occurrence rate with a mean increase from S1 to S4 of 2.1 (95% CI 1.4-2.4), p < 0.001.

CONCLUSION

As more detailed information was made available regarding potential complications with SF for AIS, parental RA toward surgery decreased and their willingness to proceed with surgery for their child improved.

Risk factors for gastrointestinal complications after spinal fusion in children with cerebral palsy

DESIGN

Prospective cerebral palsy (CP) registry review.

OBJECTIVES

(1) Evaluate the incidence/risk factors of gastrointestinal (GI) complications in CP patients after spinal fusion (SF); and (2) investigate the validity of the modified Clavien-Dindo-Sink classification.

BACKGROUND

Perioperative GI complications result in increased length of stay (LOS) and patient morbidity/mortality. However, none have analyzed the outcomes of GI complications using an objective classification system.

METHODS

A prospective/multicenter CP database identified 425 children (mean, 14.4 ± 2.9 years; range, 7.9-21 years) who underwent SF. GI complications were categorized using the modified Clavien-Dindo-Sink classification. Grades I-II were minor complications and grades III-V major. Patients with and without GI complications were compared.

RESULTS

87 GI complications developed in 69 patients (16.2%): 39 minor (57%) and 30 major (43%). Most common were pancreatitis (n = 45) and ileus (n = 22). Patients with preoperative G-tubes had 2.2 × odds of developing a GI complication compared to oral-only feeders (OR 2.2; 95% CI 0.98-4.78; p = 0.006). Similarly, combined G-tube/oral feeders had 6.7 × odds compared to oral-only (OR 6.7; 95% CI 3.10-14.66; p < 0.001). The likelihood of developing a GI complication was 3.4 × with normalized estimated blood loss (nEBL) ≥ 3 ml/kg/level fused (OR 3.41; 95% CI 1.95-5.95; p < 0.001). Patients with GI complications had more fundoplications (29% vs. 17%; p = 0.03) and longer G-tube fasting periods (3 days vs. 2 days; p < 0.001), oral fasting periods (5 days vs. 2 days; p < 0.001), ICU admissions (6 days vs. 3 days; p = 0.002), and LOS (15 days vs. 8 days; p < 0.001). LOS correlated with the Clavien-Dino-Sink classification.

CONCLUSION

Gastrointestinal complications such as pancreatitis and ileus are not uncommon after SF in children with CP. This is the first study to investigate the validity of the modified Clavien-Dindo-Sink classification in GI complications after SF. Our results suggest a correlation between complication severity grade and LOS. The complexity of perioperative enteral nutritional supplementation requires prospective studies dedicated to enteral feeding protocols.

LEVEL OF EVIDENCE

Therapeutic-level III.

Comparison of different strategies on three-dimensional correction of AIS: which plane will suffer?

PURPOSE

There are distinct differences in strategy amongst experienced surgeons from different 'scoliosis schools' around the world. This study aims to test the hypothesis that, due to the 3-D nature of AIS, different strategies can lead to different coronal, axial and sagittal curve correction.

METHODS

Consecutive patients who underwent posterior scoliosis surgery for primary thoracic AIS were compared between three major scoliosis centres (n = 193). Patients were treated according to the local surgical expertise: Two centres perform primarily an axial apical derotation manoeuvre (centre 1: high implant density, convex rod first, centre 2: low implant density, concave rod first), whereas centre 3 performs posteromedial apical translation without active derotation. Pre- and postoperative shape of the main thoracic curve was analyzed using coronal curve angle, apical rotation and sagittal alignment parameters (pelvic incidence and tilt, T1-T12, T4-T12 and T10-L2 regional kyphosis angles, C7 slope and the level of the inflection point). In addition, the proximal junctional angle at follow-up was compared.

RESULTS

Pre-operative coronal curve magnitudes were similar between the 3 cohorts and improved 75%, 70% and 59%, from pre- to postoperative, respectively (P < 0.001). The strategy of centres 1 and 2 leads to significantly more apical derotation. Despite similar postoperative T4-T12 kyphosis, the strategy in centre 1 led to more thoracolumbar lordosis and in centre 2 to a higher inflection point as compared to centre 3. Proximal junctional angle was higher in centres 1 and 2 (P < 0.001) at final follow-up.

CONCLUSION

Curve correction by derotation may lead to thoracolumbar lordosis and therefore higher risk for proximal junctional kyphosis. Focus on sagittal plane by posteromedial translation, however, results in more residual coronal and axial deformity.

New neurologic deficit and recovery rates in the treatment of complex pediatric spine deformities exceeding 100 degrees or treated by vertebral column resection (VCR)

STUDY DESIGN

Prospective multicenter international observational study.

OBJECTIVE

To investigate incidence of new neurologic deficit (NND) and the long-term recovery patterns following complex pediatric spine deformity surgery. The SRS M&M reports identify pediatric patients as having higher rate of new neurologic deficit compared with adults, while congenital and neuromuscular deformities are associated with higher new neurologic risks. Very few studies have had the large numbers of pediatric patients with curves exceeding 100 deg to ascertain the new neurologic deficit (NND) rates and recovery patterns as it relates to curve laterality and diagnosis.

METHOD

The FOX pediatric database from 17 international sites was queried for New Neurologic Deficit (NND) as characterized by change in American Spinal Injury Association (ASIA) Lower or Upper Extremity Motor Score. Recovery rates at specific intervals were recorded and related to the curve type and etiology.

RESULTS

Data of 286 consecutive patients with normal pre-operative neurologic exams were reviewed. There were 160 females vs 125 males with an average age of 14.6 years. NND occurred in 27 patients (9.4%) in the immediate post-operative period. Diagnostic categories included idiopathic scoliosis (3 patients); idiopathic kyphoscoliosis(5 patients); congenital scoliosis (7 patients); congenital kyphoscoliosis (4 patients); congenital kyphosis (6 patients), other kyphosis (1 patient) and syndromic (1 patient). 1 patient was lost to follow-up (f/u) after discharge; 1 had chronic deficits at the first post-operative erect visit (from discharge to 9 months f/u) and was subsequently lost to follow-up; 2 patients were improving at 1-year f/u but lost to subsequent f/u. 16 patients had normal neurologic function by the time of the first post-operative erect visit, 21 patients at 1-year f/u and 21 patients at the 2-year f/u. 2 patients (0.69%) had improved NND at 2-year mark.

CONCLUSION

A significant proportion of patients with complex spine deformity experience NND. However, significant improvement in neurologic function can be expected over time as seen in this study without additional surgical intervention in most cases. Congenital deformities accounted for 63% of the patients experiencing NND.