Background: Cranio-cervical connection is a well-established biomechanical concept. However, literature of this connection and its impact on cervical alignment is scarce. Chin incidence (CI) is defined as a complementary value to the angle between chin tilt (CHT) and C2 slope (C2S) axes. This study aims to investigate the relationship between cervical sagittal alignment parameters and CI with its derivatives.
Methods: A retrospective cross-sectional study carried out in a tertiary center where Computed tomography (CT) neck radiographs of non-orthopedics patients were included. They had no history of spine related symptoms or fractures in cranium or pelvis.
Results: A total of 80 patients was included with 54% of them were males. The mean of age was 30.96± 6.03. Models of predictability for c2-c7 cobb’s angle (CA) and C2-C7 sagittal vertical axis (SVA) using C2S, CHT, and CI were significant and consistent r20.585 (f(df3,76) =35.65, P ≤0.0001, r=0.764), r20.474 (f(df2,77) =32.98, P ≤0.0001, r=-0.550), respectively. Nonetheless, models of predictability for CA and SVA in relation to neck tilt (NT), T1 slope (T1S) and thoracic inlet axis (TIA) were less consistent and had a significant marginally weaker attributable effect on CA, however, no significant effect was found on SVA r20.406 (f(df1,78) =53.39, P ≤0.0001, r=0.620), r20.070 (f(df3,76) =1.904, P 0.19), respectively.
Conclusion: This study shows that obesity and aging are linked to decreased CI which will result in increasing SVA and ultimately decreasing CA.CI model has a more valid attributable effect on the sagittal alignment in comparison to TIA model.

Severe kyphoscoliotic deformities are always difficult to manage. Effectiveness of our locally developed modified halopelvic distraction device, designed using standard Ilizarov set to correct the severe kypho-scoliotic deformities before definitive surgery was assessed in the current study. Fourteen patients of age range 12-20years presented with Cobb angle of more than 90˚ were applied assembly before definitive surgery. The assembly consisted of a pelvic component having 2 Ilizarov femoral arches, connected to each other anteriorly, through a threaded rod. From the back, assembly was kept free from any rods or arches so that patient could lie supine. The Ilizarov femoral arches were anchored to the pelvis bone with 6mm Ilizarov half pins. Halo ring was anchored with the skull using 6 pins in a standard manner. Pelvic assembly and the halo ring were connected using 4 threaded rods, through which distraction was given at the rate of 2-3 mm/day. Distraction was continued from 4-8 weeks. Mean Cobb angle deformity correction of 60±10˚ was achieved and patients gained average height of 12 cm without any neurology loss. Improvement in pulmonary function test was also noted. Segmental spinal instrumentation was done as a definitive surgery. No osteotomy was needed during definitive surgery, resulting in less surgical time & fewer complications. The results of this study reveal that our modified halo-pelvic Ilizarov distraction assembly is a device with unlimited potential, which can achieve good correction in severe spinal deformities without significant risk to neurology, fewer complications and good patient compliance.

Introduction: The principle of OVCF is fixing instability, providing anterior support, and decompression. The osteoporotic spine has weak and rarified trabeculae in the cancellous bone and pedicles, which offers little resistance against screw pull-out. The study purpose was to assess the safety and efficacy of sublaminar mersilene tape augmented pedicle screws fixation for OVCFs fixation. Methods: A retrospective study of 40 consecutive patients of the OVCFs. All patients were operated with open decompression, pedicle screw fixation, and sublaminar mersilene tape augmentation. Preoperative-postoperative clinical (visual analog scale [VAS], modified Oswestry disability index [M-ODI], neurologic deficit, revision surgeries, and infection) and radiological parameters were compared to describe the utility of sublaminar mersilene tape augmented pedicle screws for OVCFs treatment. Results: Compete neurological improvement was noted in 38 patients and two patients had Frankel Garde-D neurology. The mean VAS was significantly improved from preoperative 8.98±0.60 to 2.76±0.54, final follow-up and M-ODI from 80.10±6.90 to 15.30±6.90. The mean local kyphosis angle was improved from 23.20±5.90 preoperative to 5.30°±3.9°postoperatively and 3.30°± 2.50°loss of correction at final follow-up. There was no pseudoarthrosis and implant failure noted. No iatrogenic dural or nerve injury. Conclusion: Sublaminar mersilene tape augmentation relies on the lamina for its hold, which is the strongest part of an osteoporotic vertebra. Sublaminar mersilene tape augmented pedicle screws fixation is a low-cost modality for OVCFs. It provides significant improvement in clinical and radiological outcomes. This technique is an easy learning curve, user-friendly and safe, which makes this a viable alternative option for OVCFs fixation.

Introduction: Endoscopic transforaminal discectomy has
been developed as a minimally-invasive technique for disc
herniations. It has several advantages, including lower rates
of tissue damage, with paravertebral musculature and bony
structure preservation, shorter hospitalization time, lower
morbidity and early return to activities. In this study we have
analysed the clinical and functional outcomes along with
complications of transforaminal endoscopic discectomy for
lumbar disc herniations. Patients and methods: 72 patients
with lumbar disc hernia refractory to clinical treatment
underwent endoscopic transforaminal discectomy over a two
year period ( Jan 2019 to Jan 2021). Through clinical
evaluation by the Visual Analogue Scale and functional
evaluation by the Oswestry Disability Index questionnaire,
the patients were analysed in the preoperative period, the
immediate postoperative period, at 3 months, 6 months and
1 year after surgery. Results: The mean age of the patients
was 45.9. The most affected disc was L4-L5 followed by L5-
S1. A total of 27 patients underwent 2 level discectomies. The
mean VAS scores and ODI scores decreased significantly at
one month follow up, followed by a further decrease at the
final one year follow up. Conclusion: The transforaminal
percutaneous endoscopic lumbar discectomy is a safe and
effective procedure to treat lumbar disc prolapses. Surgical
experience and correct patients selection are crucial factors
affecting the outcome.

Background: Most learning-based magnetic resonance image (MRI) segmentation methods rely on manual annotation to provide supervision, which is extremely tedious, especially when multiple anatomical structures are required. In this work, we aim to develop a hybrid framework named Spine-GFlow that combines the image features learned by a CNN model and anatomical priors for multi-tissue segmentation in sagittal lumbar MRIs.

Methods: Our framework is robust against image feature variation caused by different image setting and/or underlying pathology. Our contributions include: 1) an anatomical knowledge-driven rule-based method that automatically generates the initial seed area for different tissue types with no manual annotation required, 2) a novel proposal generation method that integrates the multi-scale image features and anatomical prior, 3) a comprehensive loss for CNN training that optimizes the pixel classification and feature distribution simultaneously. Our Spine-GFlow has been validated on a dataset containing images obtained from 3 different equipment.

Results: The segmentation results of different tissues including vertebral bodies (VB), intervertebral discs (IVD), and spinal canal (SC) are evaluated quantitatively using intersection over union (IoU) and the Dice coefficient. Results show that our method, without manual annotations, has achieved a segmentation performance comparable to a model trained with full supervision (mean Dice 0.914 vs 0.916).

Conclusion: We have introduced a hybrid framework, Spine-GFlow, for robust multi-tissue segmentation in sagittal lumbar MRIs without reliance on any human intervention and manual annotation. Our framework has significant implications for many MRI analysis tasks, including pathology detection, 3D reconstruction for further auto-diagnosis, and 3D printing.

Introduction: Management of ‘mass casualty’ situation in a pandemic can be challenging. Spinal injuries following an air crash can be fatal. Immediate triage and early definitive management holds the key in providing best outcomes. We present our report of air crash victims with spinal injuries, their patterns, morphology, management and outcomes. Methods: An analysis was performed on the spinal injuries of all patients of Boeing 737 crash landing at the Karipur international airport (Calicut, Kerala) who were treated at a tertiary care referral hospital in August 2020. Details of the initial triage, pattern of injury, morphology and mechanism, management principles and outcomes at 18 months post injury were recorded and analyzed. Results: Of the 47 patients received at our center, 44 survivors were triaged and 13 patients (29.5%) had spinal injuries of varying severity. Majority of the injuries were chance fractures at the lumbar level followed by burst and compression fractures. 6 patients underwent surgery, following all COVID-19 guidelines based on priority. All survivors had positive outcomes with our management. No complications were seen on followup. Conclusion: High incidence of spinal injuries is seen in air crash victims. Proper planning and execution in disaster management with early prioritized surgical management provides excellent outcomes.

Background: Assessment of spine alignment is crucial in the management of scoliosis, but current auto-analysis of spine alignment suffers from low accuracy. We aim to develop and validate a hybrid model named SpineHRNet+, which integrates AI and rule-based methods to improve auto-alignment reliability and interpretability.

Methods: 1,542 consecutive patients attending two scoliosis clinics were recruited. Radiographs were recaptured using smartphones or screenshots, with deidentified images securely stored. Manually labelled landmarks and alignment parameters were considered as ground truth (GT). The data were split 8:2 to train and internally test SpineHRNet+ respectively. This was followed by a prospective validation on another 337 patients. Quantitative analyses of landmark predictions were conducted, and reliabilities of auto-alignment were assessed using linear regression and Bland-Altman plots. Deformity severity and sagittal abnormality classifications were evaluated by confusion matrices. We deployed SpineHRNet+ at our open auto-analysis platform at https://www.aimed.hku.hk/alignprocare.

Results: SpineHRNet+ achieved accurate landmark detection with mean Euclidean distance errors of 2·78 and 5·52 pixels on posteroanterior and lateral radiographs, respectively. The mean angle errors between predictions and GT were 3·18° and 6·32° coronally and sagittally. All predicted alignments were strongly correlated with GT (p<0·001, R2>0·97), with minimal overall difference visualised via Bland-Altman plots. For curve detections, 95·7% sensitivity and 88·1% specificity was achieved, and for severity classification, 88·6-90·8% sensitivity was obtained. For sagittal abnormalities, greater than 85·2-88·9% specificity and sensitivity were achieved.

Conclusion: Auto-analysis provided by SpineHRNet+ was reliable, fast, and continuous. It assists clinical work and facilitates large-scale clinical studies.

Introduction
Hirayama syndrome is likely caused by a forward displacement of the posterior dura during cervical flexion leading to changes in the muscles of the fingers and wrist.
The aim of this systematic review was to document the number of reported cases, the necessity of dynamic MRI of the cervical spine and the subsequent treatment.

Methods and Materials
A systematic review was conducted and the Pubmed/Medbase, Cochrane, Google, Embase and Ovid database were searched for (Hirayama) AND ((disease) OR (syndrome)). A total of 42 studies were included for analysis reporting 2,311 patients.

Results:
The mean age was 20.2±2.26years and predominantly males (92.8%) were identified. On MRI, the “snake eyes” appearance of the spinal cord was present in 27.8% and the typical time between onset of symptoms and diagnosis was 41.5±16.4months. A variety of different treatments are reported, although there is no substantial evidence that any of them are superior to observation.

Conclusion:
The delay in diagnosis from initial presentation of symptoms show that this condition may be underdiagnosed in a variety of cases. Further, this study shows the necessity of dynamic MRIs in flexion to identify functional spinal and/or foraminal stenosis for a prompt diagnosis and subsequent treatment.

Introduction: This study aims to investigate the difference in major curve magnitude and alignment between directed and non-directed standing positioning during whole body radiographs in patients with adolescent idiopathic scoliosis(AIS) and assess their clinical implications. Methods: A total of 198 AIS patients who presented for first specialist consultation were recruited through convenience sampling. They were asked to stand in two positions for their low-dose whole body radiographs: Non-directed position, and directed position by radiographer attending to chin, shoulder and pelvis positions. Radiological assessment included Cobb angles of major and minor curves, coronal and sagittal balance. Patients with or without a major curve Cobb angle difference (of >5⁰) between positioning were compared. Over or under-representation at major curve 25⁰ or 40⁰ in non-directed positioning was examined for clinical decision making. Results: Prevalence of major curve Cobb angle difference between positioning was 22.2%. Non-directed positioning presented smaller major Cobb angle than directed positioning (median difference: 6.0⁰). Patients with Cobb angle difference had changes of shoulder balance between positioning(p=0.007). The amount of Cobb angle difference correlated to: pelvic tilt(ρ:-0.383,p<0.05) and sacral slope(ρ:0.316,p<0.05) at non-directed position, and pelvic obliquity at directed position(ρ:0.191,p<0.05). Non-directed positioning had 14.3% of major Cobb 25⁰ under-represented, 9.9% over-represented. For surgical consideration, non-directed positioning under-represented 11.1% of curves >40⁰. Conclusion: Radiographic standardized protocol should be strictly adhered for reproducing spine radiographs reliable for curve assessment. Postural variation from non-directed position can introduce under-representation of major curve Cobb angle, leading to under-estimating curve size relevant for bracing or surgical decision making.

Design: Systematic Review

Objectives: Determine the radiographic and clinical utility of postoperative orthoses following cervical spine surgery.

Methods: We performed a search of the PubMed, Cochrane Library, Medline Ovid, and SCOPUS databases from inception until November 2021. Eligible studies included outcomes of postoperative bracing versus no bracing following cervical spine surgery. The primary outcome of interest was fusion rates after cervical surgery in braced vs unbraced patients. Secondary outcomes included patient reported outcomes and complication rates.

Results: A total of 3,232 titles were initially screened. After inclusion criteria were applied, 7 studies (550 patients) were included, which compared results of braced versus unbraced patients after cervical spine surgery. These studies showed acceptable reliability for inclusion based on the Methodical Index for Non-Randomized studies (MINORS) and Critical Appraisal Skills Programme (CASP) assessment tools. There were no significant differences in fusion rates or complications between braced vs unbraced patients identified in any study. Patient reported pain and quality of life measures between braced and unbraced groups varied amongst studies, without any clear overall advantages favoring either method.

Conclusions: This systematic review found that external bracing, though widely used following cervical spine surgery, may not offer any advantages in patient-reported outcomes, as compared to not bracing. In regard to the effect of bracing on fusion rates, no strong consensus can be made as the methods of fusion assessment in the included studies were heterogenous and suboptimal. Future high-quality studies using recommended methods of fusion assessment are needed to adequately address this important question.

Purpose: To investigate the safety and feasibility of growth rod distraction procedure as ‘day care surgery’ in early onset scoliosis (EOS).
Methods: Hospital records and operation notes were retrospectively reviewed of 119 patients with focus on details of neurological events/complications during their index surgeries / lengthening procedures.
Results: 653 procedures involving primary growing rod surgeries (119 /653) and lengthening procedures (534/653) were performed in 119 patients with EOS with a mean age of 7.3+/-2.3 years. Traditional growing rods (TGR-454/534) or magnetically controlled growing rods (MCGR-80/534) were implanted and subsequent lengthening procedures (Average -4.7 (range 2-9)) were done at stipulated intervals (TGR- 6.5 months, MCGR -3.8 months). The mean anaesthesia to surgical time for TGR (96.6+/-23 minutes vs 41.3 +/- 12 minutes) and MCGR was done as outpatient procedure with mean average time of 26.2+/-9 minutes, respectively. The mean average blood loss in TGR vs MCGR was reported as 108+/-38 ml vs 0 ml .None of the patients with rod lengthening procedure required blood transfusion or experienced a neuromonitoring alert. All patients for rod lengthening procedure underwent standardized anaesthesia protocol and pain management, thereby reporting pain control (VAS-1.3+/-0.78) and mobilization within 4 hours, post operatively. Our 30-day readmission was noted in 2/119 secondary to superficial wound infection, which was managed on oral antibiotics.
Conclusion : Growth rods (TGR ,MCGR ) lengthening procedure can be safely undertaken as ‘day care surgery’ under standardized anaesthesia and pain protocol .This is especially relevant in changing paradigms of resource limitation in COVID pandemic situation worldwide.

Background: Traumatic cervical spondyloptosis (TCS) is a rare injury with only a handful of cases being described in literature. Methods: Sixteen patients of TCS operated between 2015-2019 were included. For each patient the demographic details, neurological status, associated injuries, reduction method, surgical approach, complications and outcome at final followup were recorded. Results: The mean age was 35.0 ±12.1 (range 16-65). Fall from height (56%) and road traffic accident(37.5%) were most common injury mechanisms. The most common level of injury was C6- C7 (8)> C5-C6(5) >C7-T1(2).The neurological status was ASIA A, D and B in 12, 3 and 1 patient respectively. Seven patients had one or more associated injuries. Surgical approach included anterior(A), anterior & posterior(AP), and APA approach in 8,6,2 patients respectively. A CSF leak was noticed in 6 cases. The median postoperative ICU stay was 17.5 days (2-80 days). Ten patients (62.5 %) had one or more major postoperative complications including ventilator associated pneumonia(8),persistent neurogenic shock (2), septicaemia (1), hydrocephalus (1) and meningitis (1). Four patients expired in the hospital course. Of the 10/12 discharged patients who could be followed up, 6 patients (ASIA A) expired within 12 months from complications of recumbency. Three of the remaining four, showed one grade of improvement. Conclusion: We report the largest case series of TCS to the best of our knowledge. These cases can be challenging to treat and the complication and outcomes are a function of preoperative neurological status of the patient in such cases.

Introduction: Posterior spinal fusion (PSF) or anterior spinal fusion (ASF) is the standard treatment options for AIS correction. Non-fusion anterior scoliosis correction (NFASC) is a motion sparing alternative to fusion surgery for Lenke 5 Adolescent idiopathic scoliosis (AIS). There is a dearth of literature comparing between the two techniques for Lenke 5 AIS. The current study aims to compare the clinico radiological outcomes between the two procedures at 2 years follow up. Methods:38 consecutive Lenke 5 AIS patients treated by a single surgeon with NFASC (group A) or PSF (group B) were matched by age, Cobb’s angle, and skeletal maturity. Intra operative blood loss, operative time, LOS, coronal Cobbs and SRS22 scores at 2 years were compared. Continuous variables were compared using student t-tests and categorical variables were compared using chi-square. Results:The cohort included 19 patients each in group A and B The mean follow-up of patients in group A and B were 24.5±1.8 months and 27.4±2.1 months respectively. Mean pre op thoraco lumbar/lumbar (TL/L) cobbs for group A and group B were 55°±7° and 57.5°±8° respectively. At two years follow up, the cobbs for group A and B were 18.2°±3.6° and 17.6°±3.5° respectively (p=0.09). The average operating time for group A and B were 169±14.2 mins and 219±20.5 mins respectively (p<0.05 Conclusion: Our study shows no significant difference in PSF and NFASC in terms of Cobbs correction and SRS scores, but NFASC group had significantly reduced blood loss, operative time and fewer instrumented levels while preserving flexibility.

Introduction: The Active Apex Correction (APC) technique manages EOS by actively controlling the apex through vertebral remodulation via posterior tethering while providing guided growth. This study reports the clinical outcomes in a patient cohort treated using APC as a primary and secondary intervention, with an average follow-up of 5 years.
Methods: The study comprised 27 patients (21 F,6M). In 13 patients, the primary intervention was either TGR or VEPTR, followed by APC. In the remaining patients, a standalone APC was performed. The recorded outcomes included the Cobb angle, Apical Vertebral Translation (AVT) and spinal height, besides number of surgeries, complications etc. Statistical comparisons (p ≤0.05) within the group were computed using paired ANOVA, with the Shapiro-Wilk test used to assess normality.
Results: There was a significant reduction in the Cobb angle and AVT at post-op compared to the pre-op values. At the last follow-up, the data showed maintenance of both these parameters with no significant difference compared to post-op data. Spinal height significantly increased at post-op and last follow-up, compared directly and with pre-op data. There were 26 complications leading to 14 unplanned surgeries across the cohort.
Conclusion: The long-term data for APC indicate excellent management of the deformity while allowing for significant spinal growth. Most complications (73%) and unplanned surgeries (93%) were seen in the cohort with APC used as a secondary technique. Therefore, the study strongly indicates effective management of the apex using the APC technique, highlighting the benefits of using a purely APC based management in EOS.

Introduction: Spondylolisthesis resulting in low backache, radiculopathy, and neurological involvement is a common entity. Conservative and surgical managements are available for treatment of spondylolisthesis. Cases with severe instability and neurological deficits that cannot be managed conservatively require surgical intervention. According to the SPORT trial, posterior decompression and spinal fusion
was an effective treatment. Purpose: The purpose of this study is to evaluate the clinical and functional outcomes of spondylolisthesis at the lumbosacral region managed by posterior decompression and spinal fusion. Methods: This was a prospective randomized study involving patients above 18 years, having low backache with or without sciatica, and having neurological deficits. Spondylolisthesis was diagnosed clinically, on stress radiograms and MRI studies. All patients fitting the inclusion criteria underwent posterior decompression and if needed spinal fusion for symptomatic management. Results: 30 patients participated in
this study, with 73.33% women and the rest 26.67% men (mean age 51.37 ± 12.70 years). The most commonly affected level was L4–L5 followed by L5–S1. Out of 30 patients, 3 underwent laminectomy and fixation without intervertebral fusion while one was managed with laminectomy and discectomy. The remaining patients were managed with posterior decompression and intervertebral fusion . At 6 months of follow-up, the visual analog scale score reduced from 8.70 ± 0.83 to 1.53 ± 1.38 along with reduction in Japan Orthopedic Association and Oswestry index scores.3 patients had surgical site infections while 1 had no pain relief. Conclusion: Posterior decompression and spinal fusion is an effective way in the management of lumbosacral spondylolisthesis.