Study Design. Observational serial CT analysis of the lumbar spine in a normal-aging population. Objective. Assess the natural history of IntraDiscal Vacuum Phenomenon and its role in disc degeneration. Summary of Background Data: The natural history of disc degeneration is well described but our understanding of the end stage of pathogenesis remains incomplete. MRI loses accuracy with advanced degeneration, becoming hyporesonant and indistinct. Cadaveric specimens display adaptive changes in the disc with loss of the hydrostatic capacity of the nucleus, increased intra-discal clefts and end-plate impermeability. IDVP is associated with advanced disc degeneration and CT is the optimal modality to visualise this, yet these insights remain unreported. Methods. Subjects only included historic CT abdomen scans of those over 60 years of age without acute or relevant spinal pathology, with a diagnosis of at least one level with IDVP on the original CT scan and all of whom had a similar scan >7 years later. A history of clinically significant back pain was also recorded. Results. CT scans included 360 levels in 29 males and 31 females (mean 68.9 years), displaying 82 levels of IDVP, with a second scan included after a mean of 10.3 years, Most levels displayed the same level of severity (persisted, 45) compared to where some progressed (26), regressed (8) and fused (3) ( P <0.01). There was also an increased incidence, 37/60 (62%) of developing IDVP at another level. Disc heights were reduced with increased severity of IDVP. A record of back pain was evident in 31/60 subjects, which was not significantly worse in those with worsening severity or additional level involvement over the study period. Conclusion. As disc degeneration advances, the associated IDVP persists in most cases, displaying a plateauing of severity over long periods, but rarely with progression to autofusion.

Intra-Discal Vacuum Phenomenon (IDVP) represents an intradiscal nitrogen gas accumulation where a cavity opens in a supine position, lowering intra-discal pressure and generating a bubble. IDVP has been observed in up to 20% of elderly patients and reported in almost 50% of chronic LBP patients. With a highly accurate detection on CT, its significance lacks clarity and consideration within normative data. IDVP occurs with patterns of lumbar and/or lumbopelvic morphology and associated diagnoses. Over-60s population based sample of 2020 unrelated CT abdomen scans without acute spinal presentations, with sagittal reconstructions, inclusive of T12 to femoral heads, were analyzed for IDVP and pelvic incidence (PI). Subjects with diagnostic morphological associations of the lumbar spine, including previous fracture, autofusion, transitional vertebra and listhesis, were selected out and analyzed separately. Subjects were then equally grouped into low, medium and high PI. Prevalence of lumbar spine IDVP is 41.3%. 125 cases were excluded. 1603 subjects yielded 663 IDVP. This was increased in severity towards the lumbosacral junction (L1L2 9.4%, L2L3 10.9%, L3L4 13.7%, L4L5 19.9%, L5S1 28.5%) and those with low PI, while distribution was more even with high PI. 292 had positive diagnostic associations, which were more likely to occur at the level of isthmic spondylolisthesis, adjacent to a previous fracture or suprajacent to lumbosacral transitional vertebra (p<0.05).This study has identified normative values for prevalence and severity of IDVP in a normal aging population. Morphological patterns that influence the pattern of IVDP such as pelvic incidence and diagnostic associations provide novel insights to the function of the aging spine.

Intervertebral disc (IVD) degeneration is one of the major contributing causes of low back pain (LBP), a common health issue that imposes a significant socio-economic burden on society. Previous work has demonstrated a dysregulated glycome in animal models of IVD degeneration; however, the role of glycosylation in pathogenesis is unknown. The objective of this study was to characterise altered glycan expression in IVD degeneration and elucidate the functional role of this response. Glycans in human healthy (n=6) and degenerated IVD (n=6) were examined through UPLC-MS and MALDI-IMS. These findings were correlated with proteomic analysis by LC-MS and functional in vitro studies using RNA sequencing. IVD degeneration was associated with a hypersialylated N- glycome, predominantly α-2,6 linked sialic acid. Confirming hypersialylation, we investigated sialylation’s functional role through mechanistic studies using a sialylation inhibitor (3Fax-peracetyl Neu5Ac). Sialylation inhibition in vitro modulated inflammatory and metabolic pathways, demonstrating a functional role for glycosylation in IVD degeneration. Brief summary IVD degeneration is associated with altered glycosylation, a potential target for new therapies. ### Competing Interest Statement The authors have declared no competing interest.

IntroductionInternational data describes a changing pattern to trauma over the last decade, with an increasingly comorbid population presenting challenges to trauma management and resources. In Ireland, resource provision and management of trauma is being transformed to deliver a trauma network, in line with international best practice. Our hospital plays a crucial role within this network and is designated a Trauma Unit with Specialist Services (TUSS) to distinguish it from standard trauma units.MethodsThis study aims to describe the characteristics of patients and injuries and assess trends in mortality rates. It is a retrospective observational study of adult ICU trauma admissions from August 2010 to July 2021. Primary outcome was all-cause mortality at 30-days, 90-days, and 1 year. Secondary outcomes included length of stay, disposition, and complications. Patients were categorised by age, injury severity score (ISS), and mechanism of injury.ResultsIn all, 709 patients were identified for final analysis. Annual admissions doubled since 2010/11, with a trough of 41 admissions, increasing to peak at 95 admissions in 2017/18. Blunt trauma accounted for 97.6% of cases. Falls <2m (45.4%) and RTAs (29.2%) were the main mechanisms of injury. Polytrauma comprised 41.9% of admissions. Traumatic brain injury accounted for 30.2% of cases; 18.8% of these patients were transferred to a neurosurgical centre. The majority of patients, 58.1%, were severely injured (ISS ≥ 16). Patients ≥ 65 years of age accounted for 45.7% of admissions, with falls <2m their primary mechanism of injury. The primary outcome of all-cause mortality reduced with an absolute risk reduction (ARR) of 8.0% (95% CI: -8.37%, 24.36%), 12.9% (95% CI: -4.19%, 29.94%) and 8.2% (95% CI: -9.64%, 26.09%) for 30-day, 90-day and 1-year respectively. Regression analysis demonstrated a significant reduction in mortality for 30-days and 90-days post presentation to hospital (P-values of 0.018, 0.033 and 0.152 for 30-day, 90-day and 1-year respectively).ConclusionThe burden of major trauma in our hospital is considerable and increasing over time. Substantial changes in demographics, injury mechanism and mortality were seen, with outcomes improving over time. This is consistent with international data where trauma systems have been adopted.

Introduction:Although rare in incidence, pregnancy-induced osteoporosis (PIO)-associated OVCFs represent a significant cause of morbidity for the young, peri-partum female population. Case Report:We present the case of a 27-year-old nulliparous lady who suffered seven osteoporosis vertebral compression fractures (OVCFs) with associated sagittal imbalance, the challenges posed to the attending physician or surgeon in treating this rare condition, as well as an in-depth discussion of previous literature reported on pregnancy-induced osteoporosis (PLIO) to date. Although rare in incidence, PLIO-associated OVCFs represent a significant cause of morbidity for the young, peripartum female. Conclusion:This case demonstrates how multiple PLIO-associated OVCFs may be managed successfully, with careful consideration of sagittal imbalance, using a combination of medical and non-operative orthopedic therapies at medium-term follow-up.

INTRODUCTION:Powered robotic exoskeleton (PRE) physiotherapy programmes are a relatively novel frontier which allow patients with reduced mobility to engage in supported walking. Research is ongoing regarding their utility, risks, and benefits. This article describes the case of two fractures occurring in one patient using a PRE. CASE:We report the case of a 54 year old man who sustained bilateral tibial fractures while using a PRE, on a background of T10 AIS A SCI. The initial session was discontinued due to acute severe bilateral knee swelling after approximately 15 min. The patient attended their local hospital the following day, where radiographs demonstrated bilateral proximal tibial fractures. The patient was treated with manipulation under anaesthetic and long-leg casting for five weeks, at which point he was stepped down to hinged knee braces which were weaned gradually while he remained non-weight bearing for 12 weeks. The patient was investigated with DEXA scan and was diagnosed with osteoporosis. He was liaised with rheumatology services and bone protection was initiated. Fracture healing was achieved and weight-bearing precautions were discontinued, however this period of immobilisation led to significant spasticity. The patient was discharged from orthopaedic services, with ongoing rehabilitation and physiotherapy follow-up. CONCLUSION:PRE assisted physiotherapy programmes are a promising concept in terms of rehabilitation and independence, however they are not without risk and it is important that both providers and patients are aware of this. Furthermore, SCI patients are at increased risk for osteoporosis and should be monitored and considered for bone protection.

This study investigates the biomechanics of type 2 diabetic bone fragility through a multiscale experimental strategy that considers structural, mechanical, and compositional components of ex vivo human trabecular and cortical bone. Human tissue samples were obtained from the femoral heads of patients undergoing total hip replacement. Mechanical testing was carried out on isolated trabecular cores using monotonic and cyclic compression loading and nanoindentation experiments, with bone microdamage analysed using micro-computed tomography (CT) imaging. Bone composition was evaluated using Raman spectroscopy, high-performance liquid chromatography, and fluorometric spectroscopy. It was found that human type 2 diabetic bone had altered mechanical, compositional, and morphological properties compared to non-type 2 diabetic bone. High-resolution micro-CT imaging showed that cores taken from the central trabecular region of the femoral head had higher bone mineral density (BMD), bone volume, trabecular thickness, and reduced trabecular separation. Type 2 diabetic bone also had enhanced macro-mechanical compressive properties under mechanical loading compared to non-diabetic controls, with significantly higher apparent modulus, yield stress, and pre-yield toughness evident, even when properties were normalised against the bone volume. Using nanoindentation, there were no significant differences in the tissue-level mechanical properties of cortical or trabecular bone in type 2 diabetic samples compared to controls. Through compositional analysis, higher levels of furosine were found in type 2 diabetic trabecular bone, and an increase in both furosine and carboxymethyl-lysine (an advanced glycation end-product) was found in cortical bone. Raman spectroscopy showed that type 2 diabetic bone had a higher mineral-to-matrix ratio, carbonate substitution, and reduced crystallinity compared to the controls. Together, this study shows that type 2 diabetes leads to distinct changes in both organic and mineral phases of the bone tissue matrix, but these changes did not coincide with any reduction in the micro- or macro-mechanical properties of the tissue under monotonic or cyclic loading.

Background Supracondylar humerus fractures (SCHFs) represent the most common pediatric elbow fracture, constituting approximately 12-17% of all pediatric fractures. The vast majority of operative supracondylar humerus fractures are treated with closed reduction and percutaneous pinning (CRPP); however, the estimated rate of SCHFs requiring open reduction is approximately 12.7%. Aim This study aims to analyze the likelihood of open reduction in pediatric extension-type SCHFs and to reaffirm the traditional teaching of reduction techniques described by Smith and Rang. Methods A single-surgeon retrospective analysis of 56 operative pediatric SCH cases (51 extension-type, 6 flexion-type) who underwent either CRPP or open reduction over a 16-year period was performed. All cases were performed using the aforementioned reduction technique. The Modified Gartland's classification was utilized in the analysis of extension-type SCHF radiographs. Results Gartland IIA fractures constituted 38% of SCHFs, 9% of Gartland IIB, 43% of Gartland III, and 7% of flexion-type. The rate of open reduction in SCHFs was 1.8% (1 out of 56 cases), performed in a flexion-type injury. All extension-type fractures were successfully managed with either CRPP or manipulation and casting alone. Of the cases requiring CRPP, 45% were divergent lateral wires, and 55% were crossed wires. Conclusions In our series, a 1.8% rate of open reduction was indicated in flexion-type SCH fractures. All 52 cases of extension-type SCHFs were successfully managed with closed reduction with or without percutaneous pinning. Successful closed reduction using the concept of intact periosteal hinge to aid and maintain reduction is crucial.

Intoduction:Mechanical complications from spinal fusion including implant loosening or junctional failure result in poor outcomes, particularly in osteoporotic patients. While the use of percutaneous vertebral augmentation with polymethylmethacrylate (PMMA) has been studied for augmentation of junctional levels to offset against kyphosis and failure, its deployment around existing loose screws or in failing surrounding bone as a salvage percutaneous procedure has been described in small case series and merits review. Research Question:How effective and safe is the use of PMMA as a salvage procedure for mechanical complications in failed spinal fusion?. Materials and Methods:Systematic search of online databases for clinical studies using this technique. Results:11 studies were identified, only consisting of two case reports and nine case series. Consistent improvements were observed in pre- to post-operative VAS and with sustained improvements at final follow-up. The extra- or para-pedicular approach was the most frequent access trajectory. Most studies cited difficulties with visibility on fluoroscopy, using navigation or oblique views as a solution for this. Discussion and Conclusions:Percutaneous cementation at a failing screw-bone interface stabilises further micromotion with reductions in back pain. This rarely used technique is manifested by a low but increasing number of reported cases. The technique warrants further evaluation and is best performed within a multidisciplinary setting at a specialist centre. Notwithstanding that underlying pathology may not be addressed, awareness of this technique may allow an effective and safe salvage solution with minimal morbidity for older sicker patients.

Introduction: Bone is the third most common site of metastatic cancer, of which the spine is the most frequently involved. As metastatic cancer prevalence rises and surgical tech-niques advance, operative intervention for spinal metastases is expected to rise. In the first operative cohort of spinal metastasis in Ireland, we describe the move towards less inva-sive surgery, the causative primary types and post-operative survival. Methods: This is a retrospective cohort study of all operative interventions for spinal metastasis in a tertiary referral centre over eight years. Primary spinal tumours and local invasion to the spine were excluded. Median follow up was 1895 days. Results: 225 operative procedures in 196 patients with spinal metastasis were performed over eight years. Average cases per year increased form 20 per year to 29 per year. Percutaneous procedures became more common, accounting for the majority (53%) in the final two years. The most common primary types were breast, myeloma, lung, prostate and renal. Overall survival at 1 year was 51%. Primary type was a major determinant of survival, with breast and the haematological cancers demonstrating good survival, while lung had the worst prognosis. Conclusion: This is the first descriptive cohort of operative interventions for spinal metastasis in an Irish context. Surgery for spinal metastasis is performed at an increasing rate, especially through minimally-invasive means. The majority of patients survive for at least one year post-operatively. Prudent resource planning is necessary to prepare for this growing need. (c) 2021 Published by Elsevier Ltd on behalf of Royal College of Surgeons of Edinburgh (Scottish charity number SC005317) and Royal College of Surgeons in Ireland.

Background Spinal surgery is a technically challenging endeavor with potentially devastating complications. Intraoperative neurophysiological monitoring (IONM) is a method of preventing and identifying damage to the spinal cord. Objective The aim of our study was to examine the clinical utility of IONM in spinal surgeries performed at our institution and what effect, if any, subsequent interventions had on postoperative patient outcomes. Methods This is a retrospective cohort study of 169 patients who underwent spinal surgery with IONM at 2 institutions between 2013 and 2018. Signal changes detected were recorded as well as the surgeon's response to these changes. Neurological status was recorded using a standard neurological examination and characterized as per the McCormick Neurological Scale. Patients were followed up for 12 months after surgery. Results A total of 169 spinal surgery cases with concurrent use of spinal cord monitoring were carried out in our institution between 2013 and 2018. The youngest patient was 14 years old, and the oldest was 92 years old (mean, 51.9 ± 19.6 years). There were 100 female patients and 69 male patients. Most patients (n = 124) had no signal changes. Signal changes were observed in 26.6% of the cases (n = 45). Most of these signal changes were rectified through repositioning of the patient (n = 24). The other 21 patients saw no improvement in their signals before the end of their procedures; however, these 21 patients had no postoperative deficits (grade I). This brought the false positive rate to 38% (21/55); the false negative rate was 1.8% (3/169). Conclusion This study showed similar outcomes in patients whether IONM signals were recovered or not. The false positive and false negative rates were high. Our study helps to raise awareness about IONM's strengths and weaknesses to inform future clinical practice. We recommend prioritizing clinical judgment in spinal surgery cases and using IONM with caution. Level of Evidence 3.

Intervertebral disc degeneration is a common cause of discogenic low back pain resulting in significant disability. Current conservative or surgical intervention treatments do not reverse the underlying disc degeneration or regenerate the disc. Biomaterial-based tissue engineering strategies exhibit the potential to regenerate the disc due to their capacity to modulate local tissue responses, maintain the disc phenotype, attain biochemical homeostasis, promote anatomical tissue repair, and provide functional mechanical support. Despite preliminary positive results in preclinical models, these approaches have limited success in clinical trials as they fail to address discogenic pain. This review gives insights into the understanding of intervertebral disc pathology, the emerging concept of precision medicine, and the rationale of personalized biomaterial-based tissue engineering tailored to the severity of the disease targeting early, mild, or severe degeneration, thereby enhancing the efficacy of the treatment for disc regeneration and ultimately to alleviate discogenic pain. Further research is required to assess the relationship between disc degeneration and lower back pain for developing future clinically relevant therapeutic interventions targeted towards the subgroup of degenerative disc disease patients.

INTRODUCTION:This study examined the impact of a Say-All-Fast-Minute-Everyday-Shuffled (SAFMEDS) intervention on musculoskeletal radiology interpretation ability. It addressed two research questions: 1) what degree of performance improvement in musculoskeletal radiology interpretation does SAFMEDS engender beyond usual teaching? and; 2) does the degree of improvement differ for participants who achieve behavioural fluency and those who do not? MATERIALS AND METHODS:This study used a pragmatic randomised controlled trial design. Third-year medical students were randomised to either an intervention group (n = 22), who received SAFMEDS and usual teaching, or a control group (n = 20), who received usual teaching only. Eleven participants (5 intervention group, 6 control group) did not complete participation. RESULTS:A large effect size of the SAFMEDS intervention was identified (partial η2 = 0.672; M = 38.5 min practice). When controlling for baseline performance, intervention group participants' performance on the post-test was significantly higher (M = 77.4%) than that of control group participants (M = 49.6%). Intervention group participants who achieved fluency performed significantly better at post-test (M = 82.4%) than intervention group participants who did not (M = 72.9%). CONCLUSIONS:SAFMEDS constitutes a powerful adjunct to usual teaching that produces significant improvement with a short duration of engagement, particularly when students achieve fluency in the target behaviour. Future research should consider the application of SAFMEDS, and other fluency training interventions, more widely within musculoskeletal education and orthopaedic surgery training.

The current field of orthopedics is the result of many decades of minor and major advancements. The evolution of orthopedics has culminated into the modern field seen today. This article presents 10 inventions that played a key role in shaping modern orthopedics.

AIMS:Markerless motion analysis (MMA) systems are being used extensively in the area of sports medicine and physiotherapy. The purpose of this study was to compare leg length measurements (LLM) and varus/valgus knee measurements (VVM) performed clinically, radiologically and using MMA in patients being assessed for potential total knee arthroplasty (TKR).between mean LLM calculated clinically, radiologically and using MMA (all p < 0.05). DISCUSSION & CONCLUSION:Discrepanices exist in LLM and VVM when evaluated using clinical, radiological and MMA modalities. Therefore, this study suggests that MMA alone may not be a suitable modality for assessment of patients for TKR, with a combination of two or more evaluation modalities recommended at present. LEVEL OF EVIDENCE:IV Case Series.

This review aims to identify the role of augmented, virtual or mixed reality (AR, VR or MR) technologies in setting of spinal surgery. The authors address the challenges surrounding the implementation of this technology in the operating room. A technical standpoint addresses the efficacy of these imaging modalities based on the current literature in the field. Ultimately, these technologies must be cost-effective to ensure widespread adoption. This may be achieved through reduced surgical times and decreased incidence of post-operative complications and revisions while maintaining equivalent safety profile to alternative surgical approaches. While current studies focus mainly on the successful placement of pedicle screws via AR-guided instrumentation, a wider scope of procedures may be assisted using AR, VR or MR technology once efficacy and safety have been validated. These emerging technologies offer a significant advantage in the guidance of complex procedures that require high precision and accuracy using minimally invasive interventions.

Spinal metastases are causing a treatment dilemma worldwide. As current medicine evolves, treatment of primary tumours is improving, leading to increased survival and hence later presentation of metastases. Spine is one of the main locations for metastases with thoracolumbar regions being most commonly affected. Currently treatment options are mainly for palliation and include chemotherapy, radiotherapy and surgery. A review of literature was carried to look into the current practices and evidence for the management of thoracolumbar spinal metastases. As surgical techniques are becoming more minimally invasive, a similar trend is occuring in treatment of metastatic disease. This is resulting in fewer morbidities and complications, which has a knock-on effect of increasing survival in certain patient groups. However, there are still concerns regarding the appropriate surgical approaches for thoracolumbar metastases and whether these newer minimally invasive techniques have the same oncological benefits as the standard open procedures. Future research should focus on comparing outcomes and survival rate of minimally invasive versus open surgery.

Introduction While first described in 1904, the characterisation of the peridural membrane, which is frequently encountered, yet usually unnoticed, during lumbar decompression surgery, remains inconclusive. This relatively little known membrane is continuous with the posterior longitudinal ligament and lines the epidural space. In this study, we are comparing the membrane and ligamentum flavum from patients to analyse the variations of the histological and ultrastructural compositions. Materials and methods We took samples of the membrane and ligamentum flavum from five separate patients who were undergoing lumbar spine decompression surgery for herniated discs which were then analysed with transmission electron microscopy and stained with H&E (morphology), trichrome (collagen content), and Verhoeff-Van Gieson (elastin content). Results Upon analysis of the peridural membrane, we observed tightly packed collagen fibres, interspaced with elastin fibres and very few fibroblasts. While the ligamentum flavum showed a significantly higher elastin to collagen ratio and looser arrangement of collagen fibres with a larger extracellular matrix. The peridural membrane was similar in appearance and constituent parts to the dura mater. Conclusion The peridural membrane is a distinctive and important membrane in the spinal canal, and given its high collagen to elastin ratio and it tightly packed nature, we conclude that it forms a protective layer around the spinal cord which may help in minimising the compressive nature of intervertebral disc herniation.

Summary We describe two cases of SGLT2i-induced euglycaemic diabetic ketoacidosis, which took longer than we anticipated to treat despite initiation of our DKA protocol. Both patients had an unequivocal diagnosis of type 2 diabetes, had poor glycaemic control with a history of metformin intolerance and presented with relatively vague symptoms post-operatively. Neither patient had stopped their SGLT2i pre-operatively, but ought to have by current treatment guidelines. Learning points: SGLT2i-induced EDKA is a more protracted and prolonged metabolic derangement and takes approximately twice as long to treat as hyperglycaemic ketoacidosis. Surgical patients ought to stop SGLT2i medications routinely pre-operatively and only resume them after they have made a full recovery from the operation. While the mechanistic basis for EDKA remains unclear, our observation of marked ketonuria in both patients suggests that impaired ketone excretion may not be the predominant metabolic lesion in every case. Measurement of insulin, C-Peptide, blood and urine ketones as well as glucagon and renal function at the time of initial presentation with EDKA may help to establish why this problem occurs in specific patients.