Aims. In this prospective observational study, we investigated the time-dependent changes and correlations of upper arm performance tests (ten-second test and Simple Test for Evaluating Hand Function (STEF), the Japanese Orthopaedic Association (JOA) score, and the JOA Cervical Myelopathy Evaluation Questionnaire (JOACMEQ) in 31 patients with cervical myelopathy who had undergone surgery. . Patients and Methods. We hypothesised that all the indices correlate with each other, but show slightly different recovery patterns, and that the newly described JOACMEQ is a sensitive outcome measure. Results. Peak recoveries were achieved one month post-operatively in the ten-second test and JOACMEQ upper extremity function (UEF) subscale, and at three months in the JOA and STEF scores. The recoveries of all indices were maintained until six months post-operatively. The upper extremity function (UEF) subscale in the JOACMEQ showed the strongest correlation with STEF although all the indices correlated with each other. Patients with ≥ 20 and < 20 acquired points in the UEF subscale were classified into the UEF-improved and UEF-unimproved groups. Comparisons between the groups showed that pre-operative evaluation of “coordinated motion” of the STEF was significantly low in the UEF-unimproved group. . Conclusion. These results indicate that the JOACMEQ is a concise, sensitive, patient-based outcome measure for evaluating functional recovery in patients with cervical myelopathy who have undergone surgery. Cite this article: Bone Joint J 2016;98-B:990–6

Introduction. Orthopaedic Spinal Rapid Access Service (OSRAS) was developed in our institute to provide a structured pathway for management of urgent spinal pathologies during working hours of Monday to Friday. It was delivered through a published rota by a multi displinary team of Extended Scope Practitioner carrying a bleep and a Spinal Surgeon. Aim. To evaluate the efficacy of OSRAS through a prospective audit. Results. From Nov 2013 till April 2014, 177 patients (48 Male: 119 Females) with an average age of 50 (17–95) years were referred to OSRAS. Wednesday was the busiest day with 26% referral in AM and 74% in PM. Main source of referrals were: Regional MSK services (50), Triage (34), ED (27) and GPs (20). The reasons were: suspected CESI (n=100), Acute LBP (n=30), pathological fractures (n=23), progressive neurology (n=16), discitis (n=5) and spinal stenosis (n=2). Depending on clinical need 29 patients were seen on same day, 33 next day, 53 with in 2–5 days and 31 more than 5 days. Eighty patients were discharged, 36 listed for surgery, 27 required further follow up and 31 were given telephone advise only. High user satisfaction rating was obtained. Conclusion. We propose an OSRAS model as an alternate to often un satisfactory current emergency department model, that can provide a structured pathway for timely expert management of serious spinal pathologies therefore prevent potential consequences whilst avoid unnecessary admissions. Conflicts of interest: No conflicts of interest. Sources of funding: No funding obtained

Purpose. To evaluate the competencies of spinal extended scope physiotherapists (ESP) following the introduction of requesting rights for magnetic resonance imaging (MRI) one year later. Methods. From September 2009 to August 2010 each MRI scan requested by the 2 spinal ESPs within the orthopaedic clinic was recorded along with their clinical diagnosis to ascertain why the scan was requested. This was indicated on a four point scale of likelihood of pathology which had been introduced to give evidence for MRI requesting rights. This was then audited to determine the total number of scans requested along with the accuracy or justification of the request. Results. 589 patients in total were seen in the time period by 2 spinal ESPs and of these 193 (33%) were referred for MRI scans. The breakdown of figures for the diagnosis showed that 18% of scans were for possible serious spinal pathology (SSP). 66% for lumbar spine/radiculopathy, 11% for cervical spine/radiculopathy, 2% thoracic and 3% were consideration for surgery eg. possible fusion. The accuracy of diagnosis, as measured by the clinical impression within a 4 point scoring system and its concordance with the MRI result indicated that for the lumbar spine accuracy rate was 71%, for the cervical spine 62.5%, Myelopathy 50%, SSP 16%. Conclusion. It is important that the requesting of MRIs by members of the orthopaedic team other than spinal consultants can be audited to demonstrate competency of clinical assessment and examination within the team. This results in cost effectiveness in requesting imaging appropriately according to patient needs rather than blanket referrals for scans which can be unnecessary. Data will continue to be collected and a report produced on an annual basis to ensure continuing competency

Aims. The optimal procedure for the treatment of ossification of the posterior longitudinal ligament (OPLL) remains controversial. The aim of this study was to compare the outcome of anterior cervical ossified posterior longitudinal ligament en bloc resection (ACOE) with posterior laminectomy and fusion with bone graft and internal fixation (PTLF) for the surgical management of patients with this condition. Methods. Between July 2017 and July 2019, 40 patients with cervical OPLL were equally randomized to undergo surgery with an ACOE or a PTLF. The clinical and radiological results were compared between the two groups. Results. The Japanese Orthopaedic Association (JOA) score and recovery rate in the ACOE group were significantly higher than those in the PTLF group during two years postoperatively, provided that the canal occupying ratio (COR) was > 50%, or the K-line was negative. There was no significant difference in JOA scores and rate of recovery between the two groups in those in whom the COR was < 50%, or the K-line was positive. There was no significant difference in the Cobb angle between C2 and C7, sagittal vertical axis, cervical range of motion (ROM), and complications between the two groups. Conclusion. Compared with PTLF, ACOE is a preferred surgical approach for the surgical management of patients with cervical OPLL in that it offers a better therapeutic outcome when the COR is > 50%, or the K-line is negative, and it also preserves better cervical curvature and sagittal balance. The prognosis of ACOE is similar to that of PTLE when the COR is < 50%, or the K-line is positive. Cite this article: Bone Joint J 2023;105-B(4):412–421

Aims. People with severe, persistent low back pain (LBP) may be offered lumbar spine fusion surgery if they have had insufficient benefit from recommended non-surgical treatments. However, National Institute for Health and Care Excellence (NICE) 2016 guidelines recommended not offering spinal fusion surgery for adults with LBP, except as part of a randomized clinical trial. This survey aims to describe UK clinicians’ views about the suitability of patients for such a future trial, along with their views regarding equipoise for randomizing patients in a future clinical trial comparing lumbar spine fusion surgery to best conservative care (BCC; the FORENSIC-UK trial). Methods. An online cross-sectional survey was piloted by the multidisciplinary research team, then shared with clinical professional groups in the UK who are involved in the management of adults with severe, persistent LBP. The survey had seven sections that covered the demographic details of the clinician, five hypothetical case vignettes of patients with varying presentations, a series of questions regarding the preferred management, and whether or not each clinician would be willing to recruit the example patients into future clinical trials. Results. There were 72 respondents, with a response rate of 9.0%. They comprised 39 orthopaedic spine surgeons, 17 neurosurgeons, one pain specialist, and 15 allied health professionals. Most respondents (n = 61,84.7%) chose conservative care as their first-choice management option for all five case vignettes. Over 50% of respondents reported willingness to randomize three of the five cases to either surgery or BCC, indicating a willingness to participate in the future randomized trial. From the respondents, transforaminal interbody fusion was the preferred approach for spinal fusion (n = 19, 36.4%), and the preferred method of BCC was a combined programme of physical and psychological therapy (n = 35, 48.5%). Conclusion. This survey demonstrates that there is uncertainty about the role of lumbar spine fusion surgery and BCC for a range of example patients with severe, persistent LBP in the UK. Cite this article: Bone Jt Open 2024;5(7):612–620

Aims. Surgical approaches to cervical ossification of the posterior longitudinal ligament (OPLL) remain controversial. The purpose of the present study was to analyze and compare the long-term neurological recovery following anterior decompression with fusion (ADF) and posterior laminectomy and fusion with bone graft and internal fixation (PLF) based on > ten-year follow-up outcomes in a single centre. Methods. Included in this retrospective cohort study were 48 patients (12 females; mean age 55.79 years (SD 8.94)) who were diagnosed with cervical OPLL, received treatment in our centre, and were followed up for 10.22 to 15.25 years. Of them, 24 patients (six females; mean age 52.88 years (SD 8.79)) received ADF, and the other 24 patients (five females; mean age 56.25 years (SD 9.44)) received PLF. Clinical data including age, sex, and the OPLL canal-occupying ratio were analyzed and compared. The primary outcome was Japanese Orthopaedic Association (JOA) score, and the secondary outcome was visual analogue scale neck pain. Results. Compared with the baseline, neurological function improved significantly after surgery in all patients of both groups (p < 0.001). The JOA recovery rate in the ADF group was significantly higher than that in the PLF group (p < 0.001). There was no significant difference in postoperative cervical pain between the two groups (p = 0.387). The operating time was longer and intraoperative blood loss was greater in the PLF group than the ADF group. More complications were observed in the ADF group than in the PLF group, although the difference was not statistically significant. Conclusion. Long-term neurological function improved significantly after surgery in both groups, with the improvement more pronounced in the ADF group. There was no significant difference in postoperative neck pain between the two groups. The operating time was shorter and intraoperative blood loss was lower in the ADF group; however, the incidence of perioperative complications was higher. Cite this article: Bone Jt Open 2024;5(9):768–775

Background and Purpose. The UK's NIHR and Australia's NHMRC have funded two randomised controlled trials (RCTs) to determine if lumbar fusion surgery (LFS) is more effective than best conservative care (BCC) for adults with persistent, severe low back pain (LBP) attributable to lumbar spine degeneration. We aimed to describe clinicians’ decision-making regarding suitability of patient cases for LFS or BCC and level of equipoise to randomise participants in the RCTs. Methods. Two online cross-sectional surveys distributed via UK and Australian professional networks to clinicians involved in LBP care, collected data on clinical discipline, practice setting and preferred care of five patient cases (ranging in age, pain duration, BMI, imaging findings, neurological signs/symptoms). Clinicians were also asked about willingness to randomise each patient case. Results. Of 174 responses (73 UK, 101 Australia), 70 were orthopaedic surgeons, 34 neurosurgeons, 65 allied health professionals (AHPs), 5 others. Most worked in public health services only (92% UK, 45% Australia), or a mix of public/private (36% Australia). Most respondents chose BCC as their first-choice management option for all five cases (81–93% UK, 83–91% Australia). For LFS, UK surgeons preferred TLIF (36.4%), whereas Australian surgeons preferred ALIF (54%). Willingness to randomise cases ranged from 37–60% (UK mean 50.7%), and 47–55% (Australian mean 51.9%); orthopaedic and neuro-surgeons were more willing than AHPs. Conclusion. Whilst BCC was preferred for all five patient cases, just over half of survey respondents in both the UK and Australia were willing to randomise cases to either LFS or BCC, indicating clinical equipoise (collective uncertainty) needed for RCT recruitment. Conflicts of interest. None. Sources of funding. No specific funding obtained for the surveys. DB, SA, AG and NEF have funding from the National Institute for Health Research (NIHR) UK (FORENSIC-UK NIHR134859); NEF, DB and SA have funding from the Australian National Health and Medical Research Council (NHMRC FORENSIC-Australia GA268233). AG has funding from Orthopaedic Research UK (combined with British Association of Spine Surgeons and British Scoliosis Society) and Innovate UK. NEF is funded through an Australian National Health and Medical Research Council (NHMRC) Investigator Grant (ID: 2018182)

Spinal deformations are posture dependent. Official data from the Netherlands show that youth are encountering increasing problems with the musculoskeletal system (>40% back pain, and sport injury proneness). Prolonged sloth and slumped sitting postures are causative factors. Dutch youth are “champion sitting” in Europe. The effects of sitting on the development of posture and function of locomotion (stiffness) during growth have only been reported clearly in classic textbooks (in German) of practical anatomy and orthopaedics. Research with relevant clinical examinations is being done to understand epidemiological data on the increasing posture-dependent problems. A cohort of adolescents (15–18 years) in secondary school was assessed for sagittal postural deviations while bending. 248 children completed a questionnaire, and tests were done on neuromuscular tightness. The femorotibial angle was used to measure hamstring tightness. Measurement of the dorsiflexion of the foot was used to assess the tightness of calf muscles and Achilles tendons. All adolescents were photographed laterally while performing the finger–floor test (used to test flexibility), assessed as a knockout test: “Can you reach the floor or not?” The spinal profiles while bending were classified as abnormal arcuate or angular kyphosis. Hamstring tightness was present in 62.1% of the cohort in both legs, and in 18.2% unilaterally. Achilles tendon tightness was present bilaterally in 59.3%, and unilaterally in 19.4%. Activities with presence of stiffness (finger–floor distance), in descending order, were football, running, no sports, field hockey, tennis, dance, and gymnastics. 93.5% of the soccer players had tight hamstrings in both legs compared with none of those performing gymnastics. The correlation of the finger–floor test with tight hamstrings was 73.2%. For sagittal bending deformities, the correlation between form and function deficits cannot be made yet. 80 of 248 spines were rated by the examiners as having deformed flexion. Since Andry (1741) and at the zenith of continental orthopaedics and anatomy around 1900, the prolonged flexed positions of a young spine were indicated as being the main cause of deformity by overload and shear loads on immature discs and cartilage, preventing normal development of the discs. Nachemson proved that the intradiscal pressure in sitting adults was extremely high, so it follows that children must also be at risk. Evidence suggests that youth, generally because of their sedentary and “screenful lifestyle”, will encounter serious problems in growth, manifesting as incongruent neuro-osseous growth (Roth), serious neuromuscular tightness (being prone to injury), and spinal deformations, leading to pain

Introduction. Degenerative cervical myelopathy (DCM) is associated with progressive neurological deterioration. Surgical decompression can halt but not reverse this progression. The Modified Japanese Orthopaedic Assessment (MJOA) tool is recommended by international guidelines to grade disease severity into mild, moderate and severe, where moderate and severe are both recommended to undergo surgical intervention. During Covid-19 Nottingham University Hospitals (NUH) NHS Trust, identified DCM patients as high risk for sustaining permanent neurological damage due to surgical delay. The Advanced Spinal Practitioner (ASP) team implemented a surveillance project to evaluate those at risk. Methods. A spreadsheet was compiled of all DCM patients known to the service. Patients were telephoned (Oct-Nov 2021) by an ASP. MJOA score was recorded and those describing progressive deterioration were reviewed by the ASP team on a spinal same day emergency assessment unit. Incident forms were completed for clinical deterioration and recorded as severe harm. Acute, progressive neurological deterioration was fast tracked for emergency surgical decompression. Results. 45 patients were telephoned, 18 (40%) had deteriorated. Of the 18, 9 underwent urgent surgical decompression, 6 still await surgery and 3 continue to be monitored. Those who had deteriorated were sent a formal apology and duty of candour letter. Conclusion. It appears that patients with a diagnosis of DCM deteriorate over time. Delays to timely surgical intervention can have a deleterious effect on patient's neurological function. Baseline assessment should be clearly documented and scoring system such as MJOA considered for effective monitoring. Safety netting for deterioration should be standard practice, and a clear pathway for emergency presentation identified. Conflicts of interest: No conflicts of interest. Sources of funding: No funding obtained

Aims. Although lumbosacral transitional vertebrae (LSTV) are well-documented, few large-scale studies have investigated thoracolumbar transitional vertebrae (TLTV) and spinal numerical variants. This study sought to establish the prevalence of numerical variants and to evaluate their relationship with clinical problems. Methods. A total of 1,179 patients who had undergone thoracic, abdominal, and pelvic CT scanning were divided into groups according to the number of thoracic and lumbar vertebrae, and the presence or absence of TLTV or LSTV. The prevalence of spinal anomalies was noted. The relationship of spinal anomalies to clinical symptoms (low back pain, Japanese Orthopaedic Association score, Roland-Morris Disability Questionnaire) and degenerative spondylolisthesis (DS) was also investigated. Results. Normal vertebral morphology (12 thoracic and five lumbar vertebrae without TLTV and LSTV) was present in 531 male (76.7%) and 369 female patients (75.8%). Thoracolumbar transitional vertebrae were present in 15.8% of males and 16.0% of females. LSTV were present in 7.1% of males and 9.0% of females. The prevalence of the anomaly of 16 presacral mobile vertebrae (total number of thoracolumbar vertebrae and TLTV) without LSTV was 1.0% in males and 4.1% in females, and that of the anomaly of 18 vertebrae without LSTV was 5.3% in males and 1.2% in females. The prevalence of DS was significantly higher in females with a total of 16 vertebrae than in those with normal morphology. There was no significant correlation between a spinal anomaly and clinical symptoms. Conclusion. Overall, 24% of subjects had anomalies in the thoracolumbar region: the type of anomaly differed between males and females, which could have significant implications for spinal surgery. A decreased number of vertebrae was associated with DS: numerical variants may potentially be a clinical problem. Cite this article: Bone Joint J 2021;103-B(7):1301–1308

Aims. The aim of this study was to use diffusion tensor imaging (DTI) to investigate changes in diffusion metrics in patients with cervical spondylotic myelopathy (CSM) up to five years after decompressive surgery. We correlated these changes with clinical outcomes as scored by the Modified Japanese Orthopedic Association (mJOA) method, Neck Disability Index (NDI), and Visual Analogue Scale (VAS). Methods. We used multi-shot, high-resolution, diffusion tensor imaging (ms-DTI) in patients with cervical spondylotic myelopathy (CSM) to investigate the change in diffusion metrics and clinical outcomes up to five years after anterior cervical interbody discectomy and fusion (ACDF). High signal intensity was identified on T2-weighted imaging, along with DTI metrics such as fractional anisotropy (FA). MJOA, NDI, and VAS scores were also collected and compared at each follow-up point. Spearman correlations identified correspondence between FA and clinical outcome scores. Results. Significant differences in mJOA scores and FA values were found between preoperative and postoperative timepoints up to two years after surgery. FA at the level of maximum cord compression (MCL) preoperatively was significantly correlated with the preoperative mJOA score. FA postoperatively was also significantly correlated with the postoperative mJOA score. There was no statistical relationship between NDI and mJOA or VAS. Conclusion. ms-DTI can detect microstructural changes in affected cord segments and reflect functional improvement. Both FA values and mJOA scores showed maximum recovery two years after surgery. The DTI metrics are significantly associated with pre- and postoperative mJOA scores. DTI metrics are a more sensitive, timely, and quantifiable surrogate for evaluating patients with CSM and a potential quantifiable biomarker for spinal cord dysfunction. Cite this article: Bone Joint J 2020;102-B(9):1210–1218

Purpose of study and background. Clinical researchers use Pfirrmann classification for grading intervertebral disc degeneration radiologically. Basic researchers have access to morphology and instead use the Thompson score. The aim of this study was to assess the inter-observer reliability of both classifications, along with their correlation. Methods and Results. We obtained T2-weighted MR images of 80 human lumbar intervertebral discs with various stages of degeneration to assess the Pfirrmann-score. Then the discs were dissected midsagittally to obtain the Thompson-score. The observers were typical users of both grading systems: a spine surgeon, radiology resident, orthopaedic resident, and a basic scientist, all experts on intervertebral disc degeneration. Cohen's kappa (CK) was used to determine inter-observer reliability, and intra-class correlation (ICC) as a measure for the variation between the outcomes. For the Thompson score, the average CK was 0.366 and ICC score 0.873. The average inter-observer reliability for the Pfirrmann score was 0.214 (CK) and 0.790 (ICC). Comparing the grading systems, the intra-observer agreement was 0.240 (CK) and 0.685 (ICC). Conclusion. With substantial variation between observers, the inter-observer agreements for the Pfirrmann and Thompson grading systems were moderate. This may explain the poor relationship between radiological and clinical observations in patients and raises questions about the validity of the Pfirrmann score. The mediocre intra-observer agreement between the Pfirrmann and Thompson score shows that there is no clear definition of intervertebral disc degeneration. The field is in need for a new, objective and quantitative classification system to better define and evaluate disc degeneration. There are no conflicts of interest. Funded in part by Annafonds Netherlands and Dutch Spine Society

Purpose. A Virtual Spinal Clinic (VSC) was set-up at a regional spinal referral centre to see if patient care could be improved through early advice to provide timely management, early onward referral, improve patient satisfaction and minimise chronicity. The clinic was based on the successful virtual model used throughout the country within orthopaedic fracture clinics. VSC is a Consultant led multi-disciplinary (MDT) clinic run by Advanced Practitioners (AP). Methods. A 3-month trial of the VSC was completed bi-weekly. Patients diagnosed with conservatively managed spinal fractures were referred from the on-call service. A management plan was devised by a Consultant Spinal Surgeon and communicated to patients by the AP via a telephone-call consultation where clinical advice and management could be discussed. Results. 23 clinics completed. 271 patient contacts. 216 reviewed virtually. Completed outcomes of VSC. 34.65% Discharged. 51.18% Routine appointment. 14.17% Urgent appointment. Conclusion. VSC successfully completed safe and timely assessments, management plans, telephone consultations and onward referrals for Greater Manchester patients with acute spinal fractures. Patients had earlier access to health professionals to provide advice, reassurance, complete onward referrals and safety-netting. Patient satisfaction improved, with patient reporting the telephone consultation was reassuring and allowed early return to previous function. VSC reduced patients waiting time for a follow-up appointment and reduced patients travel time across Greater Manchester. In the future, it is hoped that the 6-week follow-up telephone call service will be utilised more as VSC develops. No conflicts of interest. No funding obtained

Background. The national back pain pathway sets out the gold standard pathway for patients with back and radicular pain. To improve implementation we needed to understand current practice and identify divergences from the pathway. Objectives. 1) What patient is referred into the surgical clinic?. 2) What treatments had they tried?. 3) How many had spinal interventions. 4) Consider ways to improve the appropriateness of referrals. Method. 100 new patients attending the Spinal Orthopaedic Clinic from December 2018 to February 2019 were asked to complete a questionnaire asking about previous interventions and benefit gained. Symptoms and outcomes were recorded from the clinical entries and MRI's reviewed. Results. Over 90 had tried analgesics with only 60 reporting more than 50% benefit. Only 6 had tried neuromodulators all with poor results. 82 attended physiotherapy with 62 reporting some benefit. 84 tried exercises and 31 found it helpful whereas 17 had acupuncture and 8 of those reported benefit. 65 had consistent findings on their MRI and 31 elected to have an intervention. 8 were better, 22 wanted to self-manage and 4 went to other providers. Conclusion. 82% of our patients had tried analgesics and physical therapy before being referred to secondary care. Few opted to have an intervention and could possibly have been managed in a non-surgical clinic. If appropriate training and management is put into primary care settings, secondary care referrals could be reduced. Only 1/3 of the patients were right patient right place right time. Conflicts of interest: No conflicts of interest. Sources of funding: No funding obtained

Introduction. The aim of this study was to assess patients and healthcare professionals (HCPs) opinions on the validity of using a biopsychosocial model rather than a biomedical model in alleviating patient symptoms/pain. Method. We constructed a questionnaire to assess beliefs on the effectiveness of using a biopsychosocial or biomedical model to develop a treatment plan to optimise patient symptoms/pain. We distributed the questionnaire to new and follow-up patients and healthcare professional in the orthopaedic department. Results. 246 questionnaires were completed - 183 patients and 63 HCPs. The patient group consisted of 77 males and 106 females, the HCP group of 27 males and 36 females. 77(42%) of patients and 9(14%) of HCPs agree the biomedical model is best suited to treat symptoms. 81(44%) of patients and 62(98%) of HCPs agree the biopsychosocial model is best suited to treat symptoms. 70(38%) of patients and 61 (97%) of HCPs agree stress can increase pain. 87(48%) of patients and 62(98%) of HCPs agree distress can increase pain. 83(45%) of patients and 56(89%) of HCPs agree stress can increase disability. 81(44%) of patients and 56(89%) of HCPs agree distress can increase disability. 39(21%) of patients and 43(68%) of HCPs agree if all investigations show no abnormality in explaining symptoms, the main contributor is stress, distress or psychological/socioeconomic factor. Conclusion. HCPs recognise the biopsychosocial model as a useful tool in managing patients pain/symptoms which not recognised by patients. HCPs believe that stress, distress, psychological/socioeconomic factors have a significant impact on a patients pain and disability when compared to patients. No conflicts of interest. No funding obtained

Aims

Patients with cauda equina syndrome (CES) require emergency imaging and surgical decompression. The severity and type of symptoms may influence the timing of imaging and surgery, and help predict the patient’s prognosis. Categories of CES attempt to group patients for management and prognostication purposes. We aimed in this study to assess the inter-rater reliability of dividing patients with CES into categories to assess whether they can be reliably applied in clinical practice and in research.

Aims

Gram-negative infections are associated with comorbid patients, but outcomes are less well understood. This study reviewed diagnosis, management, and treatment for a cohort treated in a tertiary spinal centre.

Introduction. Injectable hydrogels via minimally invasive surgery reduce the risk of infection, scar formation and the cost of treatment. Degradation of the intervertebral disc (IVD) currently has no preventative treatment. An injectable hydrogel material could restore disc height, reinforce local mechanical properties, and promote tissue regeneration. We present a hydrogel material Laponite. ®. associated poly(N-isopropylacrylamide)-co-poly(dimethylacrylamide) (NPGel). Understanding how the components of this hydrogel system influence material properties, is crucial for tailoring treatment strategies for the IVD and other tissues. Methods & Results. The effect of hydrogel wt./wt., clay and co-monomer percentages were assessed using a box-Behnken design. Rheometry, SEM, FTIR and swelling was used to measure changes in material properties in simulated physiological conditions. Rheometry revealed gelation temperature of hydrogel materials could be modified with dimethyl-acrylamide co-monomer; however, final maximum mechanical properties remained unaffected. Increasing the weight % and clay % increased resultant mechanical properties from ∼500–2500 G' (Pa), increased viscosity, but retained the ability to flow through a 26G needle at 39°C. Discussion & Conclusions. By increasing the weight and clay percentage of the material we can attain greater mechanical properties, this could be beneficial for orthopaedic or even dental applications. By modifying the co-monomer percentage, we can control gelation temperature important for ensuring the material is fully set at 37°C, this could also be utilised to locally deliver drugs from the implanted material. Our current work is focused on comparing our NPGel material formulation with human IVD tissue. Acknowledgements. We would like to thank Arthritis Research UK grant number 21497 for supporting this research. No conflicts of interest. Sources of Funding: Funded by Arthritis Research UK grant number 21497

Aims

Implant-related postoperative spondylodiscitis (IPOS) is a severe complication in spine surgery and is associated with high morbidity and mortality. With growing knowledge in the field of periprosthetic joint infection (PJI), equivalent investigations towards the management of implant-related infections of the spine are indispensable. To our knowledge, this study provides the largest description of cases of IPOS to date.