Thoracic hyperkyphosis (TH – Cobb angle >40°) is correlated with rotator cuff arthropathy and associated with anterior tilting and protraction of scapula, impacting the glenoid orientation and the surrounding musculature. Reverse total shoulder arthroplasty (RTSA) is a reliable surgical treatment for patients with rotator cuff arthropathy and recent literature suggests that patients with TH may have comparable range of motion after RTSA. However, there exists no study reporting the possible link between patient-reported outcomes, humeral retroversion and TH after RTSA. While the risk of post-operative complications such as instability, hardware loosening, scapular notching, and prosthetic infection are low, we hypothesize that it is critical to optimize the biomechanical parameters through proper implant positioning and understanding patient-specific scapular and thoracic anatomy to improve surgical outcomes in this subset of patients with TH. Patients treated with primary RTSA at an academic hospital in 2018 were reviewed for a two-year follow-up. Exclusion criteria were as follows: no pre-existing chest radiographs for Cobb angle measurement, change in post-operative functional status as a result of trauma or medical comorbidities, and missing component placement and parameter information in the operative note. As most patients did not have a pre-operative chest radiograph, only seven patients with a Cobb angle equal to or greater than 40° were eligible. Chart reviews were completed to determine indications for RTSA, hardware positioning parameters such as inferior tilting, humeral stem retroversion, glenosphere size/location, and baseplate size. Clinical data following surgery included review of radiographs and complications. Follow-up in all patients were to a period of two years. The American Shoulder and Elbow Surgeons (ASES) Shoulder Score was used for patient-reported functional and pain outcomes. The average age of the patients at the time of RTSA was 71 years old, with six female patients and one male patient. The indication for RTSA was primarily rotator cuff arthropathy. Possible correlation between Cobb angle and humeral retroversion was noted, whereby, Cobb angle greater than 40° matched with humeral retroversion greater than 30°, and resulted in significantly higher ASES scores. Two patients with mean Cobb angle of 50° and mean humeral retroversion 37.5° had mean ASES scores of 92.5. Five patients who received mean humeral retroversion of 30° had mean lower ASES scores of 63.7 (p < 0 .05). There was no significant correlation with glenosphere size or position, baseplate size, degree of inferior tilting or lateralization. Patient-reported outcomes have not been reported in RTSA patients with TH. In this case series, we observed that humeral stem retroversion greater than 30° may be correlated with less post-operative pain and greater patient satisfaction in patients with TH. Further clinical studies are needed to understanding the biomechanical relationship between RTSA, humeral retroversion and TH to optimize patient outcomes

Primary care physicians rely on radiology reports to confirm a scoliosis diagnosis and inform the need for spine specialist referral. In turn, spine specialists use these reports for triage decisions and planning of care. To be a valid predictor of disease and management, radiographic evaluation should include frontal and lateral views of the spine and a complete view of the pelvis, leading to accurate Cobb angle measurements and Risser staging. The study objectives were to determine 1) the adequacy of index images to inform treatment decisions at initial consultation by generating a score and 2) the utility of index radiology reports for appropriate triage decisions, by comparing reports to corresponding images. We conducted a retrospective chart and radiographic review including all idiopathic scoliosis patients seen for initial consultation, aged three to 18 years, between January 1-April 30, 2021. A score was generated based on the adequacy of index images to provide accurate Cobb angle measurements and determine skeletal maturity (view of full spine, coronal=two, lateral=one, pelvis=one, ribcage=one). Index images were considered inadequate if repeat imaging was necessary. Comparisons were made between index radiology report, associated imaging, and new imaging if obtained at initial consultation. Major discrepancies were defined by inter-reader difference >15°, discordant Risser staging, or inaccuracies that led to inappropriate triage decisions. Location of index imaging, hospital versus community-based private clinic, was evaluated as a risk factor for inadequate or discrepant imaging. There were 94 patients reviewed with 79% (n=74) requiring repeat imaging at initial consultation, of which 74% (n=55) were due to insufficient quality and/or visualization of the sagittal profile, pelvis or ribcage. Of index images available for review at initial consult (n=80), 41.2% scored five out of five and 32.5% scored two or below. New imaging showed that 50.0% of those patients had not been triaged appropriately, compared to 18.2% of patients with a full score. Comparing index radiology reports to initial visit evaluation with <60 days between imaging (n=49), discrepancies in Cobb angle were found in 24.5% (95% CI 14.6, 38.1) of patients, with 18.4% (95% CI 10.0, 31.4) categorized as major discrepancies. Risser stage was reported in only 14% of index radiology reports. In 13.8% (n=13) of the total cohort, surgical or brace treatment was recommended when not predicted based on index radiology report. Repeat radiograph (p=0.001, OR=8.38) and discrepancies (p=0.02, OR=7.96) were increased when index imaging was obtained at community-based private clinic compared to at a hospital. Re-evaluation of available index imaging demonstrated that 24.6% (95% CI 15.2, 37.1) of Cobb angles were mis-reported by six to 21 degrees. Most pre-referral paediatric spine radiographs are inadequate for idiopathic scoliosis evaluation. Standardization of spine imaging and reporting should improve measurement accuracy, facilitate triage and decrease unnecessary radiation exposure

The purpose of this study is to evaluate risk factors for distal construct failure (DCF) in posterior spinal instrumented fusion (PSIF) in adolescent idiopathic scoliosis (AIS). We observed an increased rate of DCF when the pedicle screw in the lowest instrumented vertebra (LIV) was not parallel to the superior endplate of the LIV, however this has not been well studied in the literature. We hypothesise a more inferiorly angled LIV screw predisposes to failure and aim to find the critical angle that predisposes to failure. A retrospective cohort study was performed on all patients who underwent PSIF for AIS at the Starship Hospital spine unit from 2010 to 2020. On a lateral radiograph, the angle between the superior endplate of the LIV was measured against its pedicle screw trajectory. Data on demographics, Cobb angle, Lenke classification, instrumentation density, rod protrusion from the most inferior screw, implants and reasons for revision were collected. Of 256 patients, 10.9% (28) required at least one revision. The rate of DCF was 4.6% of all cases (12 of 260) and 25.7% of revisions were due to DCF. The mean trajectory angle of DCF patients compared to all others was 13.3° (95%CI 9.2° to 17.4°) vs 7.6° (7° to 8.2°), p=0.0002. The critical angle established is 11°, p=0.0076. Lenke 5 and C curves, lower preoperative Cobb angle, titanium only rod constructs and one surgeon had higher failure rates than their counterparts. 9.6% of rods protruding less than 3mm from its distal screw disengaged. We conclude excessive inferior trajectory of the LIV screw increases the rate of DCF and a screw trajectory greater than 11° predisposes to failure. This is one factor that can be controlled by the surgeon intraoperatively and by avoiding malposition of the LIV screw, a quarter of revisions can potentially be eliminated

Aim:. To review the use of traction x-rays under anaesthesia in Late Onset Scoliosis to correlate traction x-ray flexibility and postoperative correction using posterior nonsegmental all pedicle screw constructs. Methods:. Prospective study. Preoperative anteroposterior, lateral and side bending x-rays were done and Cobb angles were measured. Intraoperatively, traction anteroposterior x-rays were taken under anaesthesia and Cobb angles were measured. All patients underwent nonsegmental posterior all pedicle screw construct correction using Biomet implants. Cobb angles greater than 60 degees were included in the study. Calculations were done including correction rate, traction flexibility and traction correction index. Results were entered onto an excel spreadsheet and analyzed using Statistica software. Results:. 16 patients were studied, 3 boys and 13 girls, average age 14, ranging from 8 to 17 years. Preoperative Cobb angles were mean 82 (60 to 105) degrees. Traction x-rays mean Cobb angle was 42 degrees with mean traction flexibility rate 49%. Mean correction rate was 65% and mean traction correction index 106. Preoperative Cobb angles correlated with traction flexibility with a p value of 0.01. Traction x-rays Cobb angle correlated with the traction correction index (p = 0.003), postoperative x-rays (p = 0.000) and also with correction rate (p = 0.024). There was no correlation between preoperative Cobb angle and correction rate. Conclusion:. Traction x-rays under anaesthesia in late onset scoliosis are a good predictor of postoperative correction with posterior nonsegmental all pedicle screw constructs in curves greater than 60 degrees

To compare preoperative and postoperative Health Related Quality of Life (HRQoL) scores in operated Adolescent Idiopathic Scoliosis (AIS) patients with and without concomitant isthmic spondylolisthesis. A retrospective study of a prospective cohort of 464 individuals undergoing AIS surgery between 2008 and 2018 was performed. All patients undergoing surgery for AIS with a minimum 2-year follow-up were included. We excluded patients with prior or concomitant surgery for spondylolisthesis. HRQoL scores were measured using the SRS-22 questionnaire. Comparisons were performed between AIS patients with vs. without concomitant spondylolisthesis treated non-surgically. AIS surgery was performed for 36 patients (15.2 ±2.5 y.o) with concomitant isthmic spondylolisthesis, and 428 patients (15.5 ±2.4 y.o) without concomitant spondylolisthesis. The two groups were similar in terms of age, sex, preoperative and postoperative Cobb angles. Preoperative and postoperative HRQoL scores were similar between the two groups. HRQoL improved significantly for all domains in both groups, except for pain in patients with spondylolisthesis. There was no need for surgical treatment of the spondylolisthesis and no slip progression during the follow-up duration after AIS surgery. Patients undergoing surgical treatment of AIS with non-surgical management of a concomitant isthmic spondylolisthesis can expect improvement in HRQoL scores, similar to that observed in patients without concomitant spondylolisthesis

Adolescent idiopathic scoliosis is a three-dimensional deformity of the spine, affecting 1–3% of the population. Most cases are treated conservatively. Curves exceeding 45° in the thoracic spine and 40° in the lumbar spine may require correction and fusion surgery, to limit the progression of the curve and prevent restrictive pulmonary insufficiency (curves above 70°). When fusion is required, it may be performed either by posterior or anterior approaches. Posterior is useful for thoracic (Lenke I) curves, notably to correct the thoracic hypokyphosis frequently observed in AIS. Anterior approaches by thoraco-lombotomies allow an effective correction of thoraco-lumbar and lumbar curves (Lenke V and VI), with fewer levels fused than with posterior approaches. However, the approach requires diaphragm splitting and one may be concerned about the long-term pulmonary consequences. The literature provides conflicting insight regarding the consequences of the approach in anterior scoliosis correction, the interpretation of the results being difficult knowing that the correction of the scoliosis itself may improve pulmonary function. This is a retrospective observational study done at a Tertiary Institution. The HRQOL scores have been collected as a prospective cohort. Clinical and radiographic data was collected from patients charts and analysed by two senior surgeons. A cohort of 64 patients were operated in the given time period. 50 patients met the inclusion criteria. No major complications were reported. The Union rate was 100% and no post operative complications were noted. Pre and post SRS scores improved in all patients. The Anterior approach for Lenke V AIS gives great surgical exposure and allows for excellent correction of Cobb angle with minimal risk to the patient

7% of adolescent idiopathic scoliosis (AIS) patients also present with a pars defect. To date, there are no available data on the results of fusion ending proximal to a spondylolysis in the setting of AIS. The aim of this study was to analyze the outcomes of posterior spinal fusion (PSF) in this patient cohort, to investigate if maintaining the lytic segment unfused represents a safe option. Retrospective review of all patients who received PSF for AIS, presented with a spondylolysis or spondylolisthesis and had a min. 2-years follow-up. Demographic data, instrumented levels and preoperative radiographic data were collected. Mechanical complications, coronal or sagittal parameters, amount of slippage and pain levels were evaluated. Data from 22 patients were available (age 14.4 ± 2.5 years), 18 Lenke 1–2 and four Lenke 3–6. Five patients (24%) had an isthmic spondylolisthesis, all Meyerding I. The mean preoperative Cobb angle of the instrumented curves was 58 ± 13°. For 18 patients the lowest instrumented vertebra (LIV) was the last touched vertebra (LTV); for two LIV was distal to the LTV; for two, LIV was one level proximal to the LTV. The number of segments between the LIV and the lytic vertebra ranged from 1 to 6. At the last follow-up, no complications were observed. The residual curve below the instrumentation measured 8.5 ± 6.4°, the lordosis below the instrumented levels was 51.4 ± 13°. The magnitude of the isthmic spondylolisthesis remained constant for all included patients. Three patients reported minimal occasional low back pain. The LTV can be safely used as LIV when performing PSF for the management of AIS in patients with L5 spondylolysis

Abstract. Aims. Vertebral body tethering (VBT) is a non-fusion technique to correct scoliosis allowing correction of scoliosis through growth modulation (GM) by tethering the convex side to allow concave unrestricted growth similar to the hemiepiphysiodesis concept. The other modality is anterior scoliosis correction (ASC) where the tether is able to perform most of the correction immediately where limited growth is expected. Methods. A retrospective analysis of 20 patients (M:F=19:1 – 9–17 years) between January 2014 to December 2016 with a mean five-year follow-up (4 to 7). Results. There were ten patients in each group with a total of 23 curves operated upon. VBT-GM mean age −12.5 years (9 to 14), mean Risser of 0.63 (0 to 2) and VBT-ASC was 14.9 years (13 to 17) and mean Risser of 3.66 (3 to 5). Mean preoperative VBT-GM Cobb was 47.4° (40°–58°) compared to VBT-ASC 56.5° (40°–79°). Postoperative VBT-GM Cobb was 20.3° and VBT-ASC was 11.2°. The early postoperative correction rate was 54.3% versus 81% whereas Fulcrum Bending Correction Index (FBCI) was 93.1% vs 146.6%. Latest Cobb angle at mean five years' follow-up was 19.4° (VBT-GM) and 16.5° (VBT-ASC). Overall, 5% of patients required fusion. Conclusion. We show a high success rate (95%) in helping children avoid fusion at five years post-surgery. VBT is a safe technique for scoliosis correction in the skeletally immature patient. This is the first report at five years showing two possible options of VBT depending on the skeletal maturity of the patient: GM and ASC

Adolescent idiopathic scoliosis (AIS) is a complex three-dimensional deformity of the spine characterized by a Cobb angle of at least 10 degrees. The goal of surgery is to not only prevent progression but restore sagittal and coronal balance, protecting cardiopulmonary function and improving cosmesis. We reviewed the impact of deformity correction surgery in terms of radiology and patient reported outcome(PROMs). The senior authors prospectively maintained database from 2003 –2022 was retrospectively analysed in terms of pre- and post-operative patient reported outcome measures (SRS 22) as well as radiological parameters. 44 patients with AIS were identified with pre and post op PROMS. The average age at surgery was 15yrs with 84% female. 38% had a Lenke 1 curve and 3 patients had Lenke 6 curves. 73% had posterior surgery. There was a total improvement in SRS 22 scores by 7.8%. Patients reported significant satisfaction with treatment 4.8/5 and improvement in self-image with a change of 0.4 (p<0.001). However, no difference in function, pain and mental health were recorded. Overall, proximal thoracic (PT) curves improved from 24 degrees to 11 degrees (p<0.001), Main thoracic (MT) curve 55 degrees to 19 degrees and Thoracolumbar/Lumbar curves (TL/L) 45 degreesto 11 degrees. Pre-operative flexibility and post-operative correction were 0.40 and 0.41 respectively for PT curve. MT was 0.32 and 0.67. That for TL/L was 0.57 and 0.71 respectively. Surgery yields significant main curve correction correlating with high patient reported satisfaction rate. Although total SRS 22 score yielded 7.8% improvement, sub-analysis of self-image showed the most significant improvement

There is a significant positive association between hours of brace wear and rate of success in the treatment of Adolescent Idiopathic Scoliosis (AIS). The abandon rate reported in the literature averages 18%. In a recent randomized trial conducted at our center; the abandon rate was 4%. We aim to document the abandon rate towards brace treatment during the COVID-19 pandemic and its impact on AIS progression. We reviewed a database of AIS patients recruited between March and September 2020. Inclusion criteria were patients with AIS under brace treatment according to SRS criteria. The patients were divided in 2 cohorts: those with a self-reported good adherence to treatment and those who voluntarily abandoned treatment during follow-up. Patients with irregular adherence were excluded. Data analysis included age, gender, Risser stage, type of brace, Cobb angles at first visit and last follow-up (mean 11 months) and % of progression. Unpaired student tests were used for comparison. 154 patients met inclusion criteria. 20 patients were excluded due to irregular adherence. 89 patients (age: 12.1 y.o. ±1.4) reported good adherence to treatment, while 45 patients (age: 12.6 y.o. ±1.5) abandoned treatment, an abandon rate of 29%. The cohort of compliant patients started treatment with a mean main thoracic (MT) curve of 26° and finished with 27°. The mean difference between measurements was +0.65°±7.5; mean progression rate was −4.6%. However, patients who abandoned treatment started with a mean MT curve of 28° and finished with 33°, with a mean increase of +5°±8 and a mean progression rate of −11%. The differences between the 2 cohorts were statistically significant (p=0.002). Five (5) patients from the abandon group were offered for surgery because of curve progression. The abandon rate of brace treatment in AIS significantly increased during the first wave of COVID-19 pandemic. Patients who voluntarily discontinued treatment had significant increases in curve progression and surgical indication rates

Purpose of study. The aim is to assess the use of non-fusion instrumentation “growth rods” in early onset scoliosis (EOS). Methods. A retrospective review of 12 consecutive patients who had undergone a growth rod procedure for EOS was performed. Six patients had neuromuscular scoliosis, 5 had juvenile idiopathic scoliosis while one had a congenital aetiology. Growth constructs were predominately constructed from modular commercially available sets using hooks, screws and connection blocks. One VEPTR was used in a severe kyphoscoliosis. Patients returned to theatre at 6 monthly intervals for a lengthening procedure. Patients were assessed with regards to age at presentation, age at surgery, indications for surgery, initial Cobb angle, post- operative Cobb angle, number of lengthening's done, instrumentation used, amount of spine growth achieved and complications. Results. The average age at presentation was 3 yrs 8 months (birth – 7 years 5 months). The average Cobb angle was 55 (38–90). Age at index surgery ranged from 2yrs 9 months to 8 years 2 months. The Cobb angle after the first procedure averaged 37 (range 20–90). The average lengthening over 51 lengthening procedures was 8 mm. Four patients have reached the end of the process and under gone a definitive fusion with pedicle screws and growth rods. Their final Cobb angle averaged 32 (26–48). Definitive surgery was performed earlier than planned in one patient due to repetitive rod breakage. Lengthening was abandoned in one patient whose implants became septic and required removal. Two patients required revision for superior construct failure. Conclusion. The growth rod procedure allows spinal deformity correction and control as well as on-going growth in trunk height. It is a labour intensive process with a significant incidence of complications. There is however very little choice in these patients due to concerns of fusion restricting pulmonary development. NO DISCLOSURES

Subjects. A prospective study of 127 patients who underwent posterior spinal arthrodesis and segmental spinal instrumentation with iliac crest bone graft for correction of adolescent idiopathic scoliosis. Patients were divided according to their Cobb angle into two groups. Group 1 (n= 78) with a Cobb angle > 70° who underwent an additional concave rib osteotomy (CRO) and group 2 (n= 49) with a Cobb angle < 70° who did not (NCRO). All patients received a pulmonary rehabilitation programme post-operatively. Vital capacity (VC) and peak expiratory flow rate (PEF) were measured pre-operatively, at 3 months and 12 months post-operatively. Summary of background data. Concave rib osteotomy technique is used for giving more mobility and flexibility of the spine during correction especially in rigid and severe curves. Only a few studies in the literature have looked at the effect of concave rib osteotomy on pulmonary function. Results. ∗Curve correction: the mean Cobb angles at the pre-operative and final follow-up for group 1 (CRO) were 82.2° and 10.9° respectively (87% correction). In group 2 (NCRO), the mean Cobb angle was 62.77% pre-operatively and 6.9% at the final follow-up (89% correction achieved). ∗Pulmonary function: Pre-operative: there was no significant difference between the 2 groups. 3 Months post-operative: the mean VC was 40.4% in group 1 and 48.05% in group 2 (p=0.05). The mean PEF was 27.38 % in group 1and 34.1% in group 2 (p = 0.02). 12 Months post-operative: the mean VC in group 1 was 102.4% versus 103.5% in group 2 (p = 0.43). The mean PEF in group 1 was 76.2% versus 73.5% in group 2 (p = 0.32). Conclusions. Concave Rib Osteotomy technique has a definite effect on the pulmonary function in the early post-operative period. However, this difference resolves with time and both groups had a similar outcome a year post-operatively

Neuromuscular scoliosis patients face rates of major complications of up to 49%. Along with pre-operative risk reduction strategies (including nutritional and bone health optimization), intra-operative strategies to decrease blood loss and decrease surgical time may help mitigate these risks. A major contributor to blood loss and surgical time is the insertion of instrumentation which is challenging in neuromuscular patient given their abnormal vertebral and pelvic anatomy. Standard pre-operative radiographs provide minimal information regarding pedicle diameter, length, blocks to pedicle entry (e.g. iliac crest overhang), or iliac crest orientation. To minimize blood loss and surgical time, we developed an “ultra-low dose” CT protocol without sedation for neuromuscular patients. Our prospective quality improvement study aimed to determine: if ultra-low dose CT without sedation was feasible given the movement disorders in this population; what the radiation exposure was compared to standard pre-operative imaging; whether the images allowed accurate assessment of the anatomy and intra-operative navigation given the ultra-low dose and potential movement during the scan. Fifteen non-ambulatory surgical patients with neuromuscular scoliosis received the standard spine XR and an ultra-low dose CT scan. Charts were reviewed for etiology of neuromuscular scoliosis and medical co-morbidities. The CT protocol was a high-speed, high-pitch, tube-current modulated acquisition at a fixed tube voltage. Adaptive statistical iterative reconstruction was applied to soft-tissue and bone kernels to mitigate noise. Radiation dose was quantified using reported dose indices (computed tomography dose index (CTDIvol) and dose-length product (DLP)) and effective dose (E), calculated through Monte-Carlo simulation. Statistical analysis was completed using a paired student's T-test (α = 0.05). CT image quality was assessed for its use in preoperative planning and intraoperative navigation using 7D Surgical System Spine Module (7D Surgical, Toronto, Canada). Eight males and seven females were included in the study. Their average age (14±2 years old), preoperative Cobb angle (95±21 degrees), and kyphosis (60±18 degrees) were recorded. One patient was unable to undergo the ultra-low dose CT protocol without sedation due to a co-diagnosis of severe autism. The average XR radiation dose was 0.5±0.3 mSv. Variability in radiographic dose was due to a wide range in patient size, positioning (supine, sitting), number of views, imaging technique and body habitus. Associated CT radiation metrics were CTDIvol = 0.46±0.14 mGy, DLP = 26.2±8.1 mGy.cm and E = 0.6±0.2 mSv. CT radiation variability was due to body habitus and arm orientation. The radiation dose differences between radiographic and CT imaging were not statistically significant. All CT scans had adequate quality for preoperative assessment of pedicle diameter and orientation, obstacles impeding pedicle entry, S2-Alar screw orientation, and intra-operative navigation. “Ultra-low dose” CT scans without sedation were feasible in paediatric patients with neuromuscular scoliosis. The effective dose was similar between the standard preoperative spinal XR and “ultra-low dose” CT scans. The “ultra-low dose” CT scan allowed accurate assessment of the anatomy, aided in pre-operative planning, and allowed intra-operative navigation despite the movement disorders in this patient population

Neuromuscular scoliosis patients face rates of major complications of up to 49%. Along with pre-operative risk reduction strategies (including nutritional and bone health optimization), intra-operative strategies to decrease blood loss and decrease surgical time may help mitigate these risks. A major contributor to blood loss and surgical time is the insertion of instrumentation which is challenging in neuromuscular patient given their abnormal vertebral and pelvic anatomy. Standard pre-operative radiographs provide minimal information regarding pedicle diameter, length, blocks to pedicle entry (e.g. iliac crest overhang), or iliac crest orientation. To minimize blood loss and surgical time, we developed an “ultra-low dose” CT protocol without sedation for neuromuscular patients. Our prospective quality improvement study aimed to determine:. if ultra-low dose CT without sedation was feasible given the movement disorders in this population;. what the radiation exposure was compared to standard pre-operative imaging;. whether the images allowed accurate assessment of the anatomy and intra-operative navigation given the ultra-low dose and potential movement during the scan. Fifteen non-ambulatory surgical patients with neuromuscular scoliosis received the standard spine XR and an ultra-low dose CT scan. Charts were reviewed for etiology of neuromuscular scoliosis and medical co-morbidities. The CT protocol was a high-speed, high-pitch, tube-current modulated acquisition at a fixed tube voltage. Adaptive statistical iterative reconstruction was applied to soft-tissue and bone kernels to mitigate noise. Radiation dose was quantified using reported dose indices (computed tomography dose index (CTDIvol) and dose-length product (DLP)) and effective dose (E), calculated through Monte-Carlo simulation. Statistical analysis was completed using a paired student's T-test (α= 0.05). CT image quality was assessed for its use in preoperative planning and intraoperative navigation using 7D Surgical System Spine Module (7D Surgical, Toronto, Canada). Eight males and seven females were included in the study. Their average age (14±2 years old), preoperative Cobb angle (95±21 degrees), and kyphosis (60±18 degrees) were recorded. One patient was unable to undergo the ultra-low dose CT protocol without sedation due to a co-diagnosis of severe autism. The average XR radiation dose was 0.5±0.3 mSv. Variability in radiographic dose was due to a wide range in patient size, positioning (supine, sitting), number of views, imaging technique and body habitus. Associated CT radiation metrics were CTDIvol = 0.46±0.14 mGy, DLP = 26.2±8.1 mGy.cm and E = 0.6±0.2 mSv. CT radiation variability was due to body habitus and arm orientation. The radiation dose differences between radiographic and CT imaging were not statistically significant. All CT scans had adequate quality for preoperative assessment of pedicle diameter and orientation, obstacles impeding pedicle entry, S2-Alar screw orientation, and intra-operative navigation. “Ultra-low dose” CT scans without sedation were feasible in paediatric patients with neuromuscular scoliosis. The effective dose was similar between the standard preoperative spinal XR and “ultra-low dose” CT scans. The “ultra-low dose” CT scan allowed accurate assessment of the anatomy, aided in pre-operative planning, and allowed intra-operative navigation despite the movement disorders in this patient population

Introduction. Radiographic parameters have been shown to have a poor correlation with clinical outcome after open scoliosis procedures. However this has not been previously addressed after endoscopic surgery. The purpose of our study was to examine prospectively the relationship between curve correction and clinical outcome for endoscopic scoliosis surgery. Methods. We studied 50 consecutive patients who underwent endoscopic instrumentation, with a minimum follow-up of two years. All patients were assessed pre-operatively and at 24 months post-operatively. Radiological parameters were measured from plain standing radiographs including the coronal Cobb angle, sagittal alignment, coronal alignment and shoulder elevation. Clinical outcome was assessed using the Scoliosis Research Society Outcomes Instrument (SRS-24). Correlation between radiological parameters and SRS-24 scores were determined using the Pearson correlation coefficient. Results. There were 45 females and 5 males with a mean age of 16.4 years (range, 10 to 46). The pre-operative coronal Cobb angle was mean 51.7 ± 8.5 and the post-operative instrumented Cobb angle was mean 20.4 ± 7.8 corresponding to a mean curve correction of 60.7%. There was a positive correlation between instrumented Cobb angle and total SRS-24 score (p=0.03, r2=0.085) and between curve correction and total SRS-24 score (p=0.04, r2=0.081). No correlation was found between coronal alignment, sagittal alignment, shoulder elevation or size of rib hump and the SRS-24 scores (p>0.05). Conclusions. Overall endoscopic scoliosis surgery was associated with a good clinical outcome for our series of patients. Using a validated assessment instrument, clinical outcome correlated well with the amount of curve correction achieved

Introduction. Idiopathic scoliosis is a lateral curvature of the spine >10° as measured on a frontal plane radiograph by the Cobb angle. Important variables in assessing the risk of curve progression include a young age at presentation, female sex, a large amount of growth remaining, the rate of growth, the curve magnitude, and the curve location. Curves >20° have an inherently low risk of progression. Surgery is indicated for curves >50° or rapidly progressing curves. The timing of surgery is paramount in order to intervene in cases where rapid progression is evident to prevent further deterioration. There is a greater likelihood for more complex surgery to be required in major curves. At present, there are severe restrictions on resources to cater for patients with scoliosis. As a result, patients spend excessive periods on waiting lists prior to having their procedure. The aim of this study is to analyse the progression of curves of patients while on the waiting list and assess the cost implications of curve deterioration. Methods. A retrospective analysis of 40 cases of adolescent idiopathic scoliosis performed from between 2007-2010 was carried out. All radiographs at the time of being placed on the waiting list and the time of admission were reviewed to assess the Cobb angle. The radiographs were analysed independently by three spinal surgeons to determine what level of surgical intervention they would recommend at each time point. The final procedure performed was also recorded. A cost analysis was carried out of all of the expenses that are incurred as part of scoliosis surgery, including length of hospital stay, intensive care admission, spinal monitoring, implant cost, and the requirement for multiple procedures. Results. The average time on the waiting list was 12 months (range 6 – 16 months). Comparison of radiographs at the time of listing and time of admission revealed a deterioration of the Cobb angle by an average of 12°. The average Cobb angle at time of surgery was 78° (range 55° - 96°). Analysis of cost implications revealed an increase in cost based on implant requirements, length of stay and intensive care admission estimated at 25%. Conclusion. The results of this study demonstrate that there is a significant deterioration of scoliosis curvature in patients while on the waiting list. The consequence of this progression results in longer operative time, increased requirement for intensive care beds, an increase in requirements for additional levels of pedicle instrument, and a prolonged length of stay. The implications of the deterioration in curvature result in an increase in overall cost estimated at 25%. Waiting list initiatives established over the past 6 months have reduced the waiting list to 6-9 months. Further efforts to continue this initiative are likely to give rise to further cost reductions and result in more manageable curvatures being dealt with in a timely fashion

Purpose. To correlate the initial brace correction with quantity and quality of brace wear within the first 6 months for the treatment of adolescent idiopathic scoliosis (AIS). Method. Brace treatment for AIS has been debated for years. Prediction of treatment outcomes is difficult as the actual brace usage is generally unknown. As technology became more advanced, electronic devices were able to measure adherence in both quantity (how much time the brace has been worn) and quality (how tightly the brace has been worn) of brace usage without need for patient interaction. The developed adherence monitor consisted of a force sensor and a data acquisition unit. Subjects were monitored within the first 6 months of brace wear. The data sample rate was set to be one sample per minute. Data was downloaded at the patients routine clinical visits. The prescription, first in-brace and first follow-up out-of-brace Cobb angles were measured. Twelve AIS subjects (10F, 2M), age between 9.8 and 14.7 years, average 11.9 1.5 years, who were prescribed a new TLSO and full-time brace wear (23 hours/day) participated. All braces were made by the same orthotist. The force value at the major pressure pad at the prescribed tightness level was recorded as the individualized reference value. The normalized force value (measured force magnitude relative to the individualized reference value) was used for the quality factor. The time of brace usage relative to the prescribed time was used as the quantity factor. Results. The first in-brace follow-up visit was approximately 2 months after the brace fitting session and the first out-of-brace follow-up visit was scheduled after 4 months. The Cobb angle of the major curve prior to bracing, in-brace and at the first follow-up out-of-brace were 31.3 6.2, 16.5 8.7 and 31.8 7.1 degrees, respectively. The mean reference force value was 1.1 0.23N. The average quantity and quality of the brace usage were 61.2 12.2% and 63.4 8.8%, respectively. A relationship was found between wear time with a change in Cobb angle (pre brace – the first follow-up out-of-brace) (r = 0.77). The more time that the brace was worn resulted in a better treatment result. A moderate correlation was found between the force value at the major pressure pad and the in-brace correction (r = 0.40). Also, a moderate relationship was found between wear quality during daytime with a change in Cobb angle (r = 0.67). The more time that the brace was worn close to the prescribed tightness level during the daytime resulted in a better outcome. Conclusion. This study showed the brace effectiveness is dependent on both the quantity and quality of brace usage

Introduction. Luk (Luk et al. Spine vol 23(21) 2303-2307 1998) has shown that in posterior surgery, the correction achieved can be predicted by fulcrum bending films. The relevance to anterior correction has been disputed, as this commonly involves shortening the spine by the removal of intervertebral discs. The aim of the study was to see whether the pre-operative bending angle reflected the degree of correction achieved. Method. 91 patients with a structural thoracic curve had an anterior endoscopic correction using a single rod. The mean age was 16.1 years. (range 10-46) The majority of curves were Lenke type 1 (79%) or Type 2 (8%). In all cases disc clearance and bone grafting were performed. All had pre-operative fulcrum bending films. The mean Cobb angle achieved at the pre-operative bending film was compared with the post-operative correction at 2 months. The FBCI (Fulcrum Bending Correction Index) and correction rates were also calculated. The FBCI is calculated by dividing the correction rate by the fulcrum flexibility and expressed as a percentage. It takes into account the pre-operative flexibility of the curve. Results. The mean Cobb angle achieved at the pre-operative bending film was 20.4 degrees. The mean Cobb angle of the corrected curve at 2 months following surgery was 20.4 degrees, (p=0.96). The mean FBCI was 107%. The overall correction rate was 60.1%. Conclusion. In our series fulcrum bending films have been highly predictive of the correction achieved following anterior endoscopic correction. The correction rate of 60.1% is in keeping with other series. In addition, the FBCI was 107%. The instrumentation had corrected to the flexibility achieved at the time of the pre-operative bending films. This implies that the discectomies performed at time of surgery had not significantly increased the correction achieved

Our prospective observational study of patients treated for Thoracolumbar Adolescent Idiopathic Scoliosis (AIS) by anterior instrumentation aimed at investigating the correlation between the radiographic outcome and the recently-developed scoliosis research society self-reported outcomes instrument (SRS-22) which has been validated as a tool for self-assessment in scoliosis patients. Previous patient based questionnaires demonstrated poor correlation with the radiological parameters. Materials and Methods. Pre-operative, post-operative and two years follow-up radiographs of 30 patients were assessed. Thirteen radiographic parameters including Cobb angles and balance were recorded. The percentage improvements for each were noted. The SRS-22 questionnaire was completed by all patients at final follow-up. Correlation was sought between each radiographic parameter, total SRS score and each of the five domains by quantifying Pearson's Correlation Coefficient (r). Results. Percentage improvement in primary Cobb angle (r = 0.052), secondary Cobb angle (r = 0.165), apical vertebra translation of the primary curve (r = -0.353), thoracic kyphosis (r = 0.043) and lumbar lordosis (r = 0.147) showed little or no correlation with the SRS-22 total score and its five individual domains. Significant inverse correlation was found between the upper instrumented vertebra angle and at follow-up and SRS-22 (r = -0.516). The same was true for Sagittal plumb line shift at final follow up (r = -0.447). Conclusion. SRS-22 is a validated tool for the self-assessment of health status in spinal deformity patients; however, it does not seem to correlate with most of the radiographic parameters commonly used by clinicians to assess patient outcome with the exception of upper instrumented vertebra angle and sagittal plumb line which do correlate significantly with the SRS-22 outcomes instrument. A comprehensive system of assessing the success of surgery both from the patient and clinicians perspective is required in the spinal deformity patient

Purpose. A change in lumbar lordosis can affect the outcome following lumbar fusion, and intraoperative positioning is a prime determinant of the postoperative lordosis. The purpose of this study is to determine the change in lordosis and sacral slope (SS) following axial lumbar interbody fusion (AxiaLIF). Method. We retrospectively reviewed 81 patients who underwent a 360 lumbar interbody fusion at L4-5/L5-S1 (two-level procedure) or solely at L5-S1 (one-level) for degenerative disc disease and spondylolithesis utilizing the AxiaLIF with posterior segmental instrumentation. For the two-level procedures, 25 patients had the AxiaLIF placed first and 27 had pedicle screws placed first. For the one-level procedures, 11 patients had the AxiaLIF placed first and 18 had pedicle screws placed first. Standing lateral preoperative radiographs were compared to standing lateral postoperative films. Lumbar Cobb angles were measured at L1-S1, L4-S1 and individual lumbar levels. SS was measured for sacral version. Results. Of the 81 patients studied, 29 underwent one-level AxiaLIF, and 52 underwent two-level AxiaLIF. For the two-level population, there were statistically significant changes (P less than 0.05) in Cobb angles pre- vs. postoperative at the L4-S1, L2-3, and L4-5 levels, but none other. The percent lordosis from L4-S1 pre- vs. postoperative was also noted to be significant. The pre- vs. postoperative Cobb angle comparisons for the one-level population were not found to be significant. The percentages having a greater than or equal to 10 degree change in total lordosis and lordosis from L4-S1 in both one- and two-level groups were similar at ∼20%. There was no difference in either group in percentage having a greater than or equal to five degree change at individual lumbar segments although there was a trend at both L5-S1 and the SS towards less change with the pedicle screws placed first. Conclusion. A significant portion of both single and multilevel fusions with AxiaLIF had a statistically significant change at the L4-5 and L4-S1 levels. In general, there is a small decrease in lordosis at the bottom two segments and SS with reciprocal changes at the proximal levels. The percentage of total lordosis from the L4-S1 level decreased significantly in the multilevel group. Roussouly lordosis type three (well-balanced) was relatively protected from change in lordosis. Placing pedicle screws prior to placing the AxiaLIF in one- and two- level procedures may lead to an improved sagittal alignment. Further observation of this cohort will determine if the change in alignment will impact outcomes or accelerate adjacent level disease