Introduction. The change of position of the distal pedicle screws with growing rods in relation to vertebral bodies was described as pedicle screws
Background. We have previously reported an injectable hydrogel (NPgel), which could deliver patients own stem cells, via small bore needles, decreasing damage to the annulus fibrosus. NPgel drives differentiation to NP cells and can inhibit the degenerate niche. However, clinical success of NPgel is dependent on the capacity to inject NPgel into naturally degenerate human discs, restore mechanical function to the IVD, prevent extrusion during loading and induce regeneration. This study assessed injectability of NPgel into human IVD, influence on mechanical properties, regeneration ability in an ex vivo culture system and retention under failure testing. Methodology. Cadaveric human discs were used to calculate disc height and to determine Youngs Modulus during simulated walking pre and post injection of NPgel, extrusion testing performed. Whole human IVDs were injected with NPgel +/− human BMPCs and maintained in culture under physiological loading regime for 4 weeks. Pre and post culture MRI imaging and in line biomechanical characteristics determined. Histology and immunochemistry performed for anabolic and catabolic factors. Results. NPgel injection significantly increased disc height and Youngs modulus with no extrusion observed during failure testing. T1ρ intensity was increased during culture in those injected with NPgel +/− cells compared to non-injected discs, and biomechanical restoration. Histological analysis has demonstrated excellent tissue attachment to the injected gel, and cellular
Introduction. We have developed a new synthetic hydrogel that can be injected directly into the intervertebral disc (IVD) without major surgery. Designed to improve fixation of joint prosthesis, support bone healing or improve spinal fusion, the liquid may support the differentiation of native IVD cells towards osteoblast-like cells cultured within the hydrogel. Here we investigate the potential of this gel system (Bgel) to induce bone formation within intervertebral disc tissue. Methods. IVD tissue obtained from patients undergoing discectomy, or cadaveric samples, were cultured within a novel explant device. The hydrogel was injected, with and without mesenchymal stem cells (MSCs), and cultured under hypoxia, to mimic the degenerate IVD environment, for 4 weeks. Explants were embedded to wax and native cellular
Degenerative cervical spondylosis (DCS) is a common musculoskeletal disease that encompasses a wide range of progressive degenerative changes and affects all components of the cervical spine. DCS imposes very large social and economic burdens. However, its genetic basis remains elusive. Predicted whole-blood and skeletal muscle gene expression and genome-wide association study (GWAS) data from a DCS database were integrated, and functional summary-based imputation (FUSION) software was used on the integrated data. A transcriptome-wide association study (TWAS) was conducted using FUSION software to assess the association between predicted gene expression and DCS risk. The TWAS-identified genes were verified via comparison with differentially expressed genes (DEGs) in DCS RNA expression profiles in the Gene Expression Omnibus (GEO) (Accession Number: GSE153761). The Functional Mapping and Annotation (FUMA) tool for genome-wide association studies and Meta tools were used for gene functional enrichment and annotation analysis.Aims
Methods
The aim of this study was to compare outcomes after growth-friendly treatment for early-onset scoliosis (EOS) between patients with skeletal dysplasias versus those with other syndromes. We retrospectively identified 20 patients with skeletal dysplasias and 292 with other syndromes (control group) who had completed surgical growth-friendly EOS treatment between 1 January 2000 and 31 December 2018. We compared radiological parameters, complications, and health-related quality of life (HRQoL) at mean follow-up of 8.6 years (SD 3.3) in the dysplasia group and 6.6 years (SD 2.6) in the control group.Aims
Methods
Clinical and radiological indicators of outcome in the use of X-Stops were sought by evaluating patient-centred outcomes alongside radiographic scrutiny of changes around implants with correlation to outcome. Prospectively collated outcome scores were correlated to outcome, with retrospective analysis of pre-operative MRI scans and 117 post-operative radiographs. Single surgeon series of 44 patients(52 implants). Clinical - ODI, walking distance, Low Back Outcome Score, MZDI and MSP. Radiographic - lucency(anterior and cranio-caudal to implant), coronal rotation, dorsal
Open discectomy (OD) is the standard operation for lumbar disc herniation (LDH). Percutaneous endoscopic lumbar discectomy (PELD), however, has shown similar outcomes to OD and there is increasing interest in this procedure. However despite improved surgical techniques and instrumentation, reoperation and infection rates continue and are reported to be between 6% and 24% and 0.7% and 16%, respectively. The objective of this study was to compare the rate of reoperation and infection within six months of patients being treated for LDH either by OD or PELD. In this retrospective, nationwide cohort study, the Korean National Health Insurance database from 1 January 2007 to 31 December 2018 was reviewed. Data were extracted for patients who underwent OD or PELD for LDH without a history of having undergone either procedure during the preceding year. Individual patients were followed for six months through their encrypted unique resident registration number. The primary endpoints were rates of reoperation and infection during the follow-up period. Other risk factors for reoperation and infection were also evalulated.Aims
Methods
Background. We have reported an injectable L-pNIPAM-co-DMAc hydrogel with hydroxyaptite nanoparticles (HAPna) which promotes mesenchymal stem cell (MSC) differentiation to bone cells without the need for growth factors. This hydrogel could potentially be used as an osteogenic and osteoconductive bone filler of spinal cages to improve vertebral body fusion. Here we investigated the biocompatibility and efficacy of the hydrogel in vivo using a proof of concept femur defect model. Methods. Rat sub-cut analysis was performed to investigate safety in vivo. A rat femur defect model was performed to evaluate efficacy. Four groups were investigated: sham operated controls; acellular L-pNIPAM-co-DMAc hydrogel; acellular L-pNIPAM-co-DMAc hydrogel with HAPna; L-pNIPAM-co-DMAc hydrogel with rat MSCs and HAPna. Following 4 weeks, defect site and organs were histologically examined to determine integration, repair and inflammatory response, as well as Micro-CT to assess mineralisation. Results. No inflammatory reactions or toxicity were seen in any animal. Enhanced bone healing was observed in aged exbreeder female rats where hydrogel was injected with increased deposition of collagen type I. Integration of the hydrogel with surrounding bone was observed without the need for delivered MSCs; native cell infiltration was also seen and bone formation was observed within all hydrogel systems investigated. Conclusion. This novel hydrogel is biocompatible, facilitates
Ankylosing spondylitis (AS) is a progressive
multisystem chronic inflammatory disorder. The hallmark of this pathological
process is a progressive fusion of the zygapophyseal joints and
disc spaces of the axial skeleton, leading to a rigid kyphotic deformity
and positive sagittal balance. The ankylosed spine is unable to
accommodate normal mechanical forces, rendering it brittle and susceptible
to injury. Traumatic hyperextension injury of the cervical spine
leading to atlantoaxial subluxation (AAS) in AS patients can often
be fatal. We report a non-traumatic mechanism of injury in AS progressing
to AAS attributable to persistent hyperextension, which resulted
in fatal
Introduction. Recently published results suggest insertion of shorter screws in L5/S1 stand-alone anterior interbody fusion, fearing S1 nerve root violation. However, insertion of shorter screws led to screw fixation failure and new onset of S1 body fractures. Material and Methods. Retrospective review of patients with L5/S1 stand-alone anterior interbody fusion, focussing on screw length, radiological outcomes (especially metal work failure, screw fixation and S1 body fractures) and new onset of S1 nerve root irritation. Results. 38 patients were included (mean age 46.2±13.3 years, 21 females, 17 males). Fusion of the L5/S1 segment was performed in between 2003-2010; postoperative follow-up ranged from 2-24 months. 15 patients had multilevel surgery (7 multiple segmental fusion, 8 hybrid procedures). Screw length ranged from 20-30 mm. No patient had new postoperative S1 nerve root irritation. Interestingly, 2 patients out of the hybrid group had a new onset of L5 radiculopathy, concordant to the level of disc-replacement. Follow-up x-ray review showed no fracture of S1 body fractures in all patients. No evidence of screw loosening,
Introduction. Many methods are available for distal anchoring of spine-based and rib-based growing rod systems for early-onset scoliosis. One of these methods, pelvic S-hooks, was initially recommended for patients with spina bifida or for those with severe thoracolumbar curves. No study has yet analysed the clinical and radiographic effects of S-hooks on patients with rib-based instrumentation. The purpose of this study is to retrospectively review the results of S-hook pelvic fixation in patients with rib-based instrumentation. Methods. A multicentre, retrospective study, approved by the institutional review board, was undetaken in all patients treated with rib-based constructs using S-hooks for pelvic fixation. Preoperative and postoperative clinical variables, radiological measurements, and the incidence and management of complications were evaluated in patients with a minimum follow-up of 2 years. Results. 44 patients, 26 of whom were girls, were studied and had a mean age at surgery of 71 months. The most common surgical indication was progressive neuromuscular scoliosis. The average preoperative Cobb angle was 64° and at most recent follow-up (mean 45 months) was 53°. The most common construct was dual rods resting over the iliac crest without suture to the iliac crest extending from T3/T4 ribs to the pelvis using domino connectors. 45% of the patients had complications, of which S-hook
To investigate metallosis in patients with magnetically controlled growing rods (MCGRs) and characterize the metal particle profile of the tissues surrounding the rod. This was a prospective observational study of patients with early onset scoliosis (EOS) treated with MCGRs and undergoing rod exchange who were consecutively recruited between February 2019 and January 2020. Ten patients were recruited (mean age 12 years (SD 1.3); 2 M:8 F). The configurations of the MCGR were studied to reveal the distraction mechanisms, with crucial rod parts being the distractable piston rod and the magnetically driven rotor inside the barrel of the MCGR. Metal-on-metal contact in the form of ring-like wear marks on the piston was found on the distracted portion of the piston immediately outside the barrel opening (BO) through which the piston rod distracts. Biopsies of paraspinal muscles and control tissue samples were taken over and away from the wear marks, respectively. Spectral analyses of the rod alloy and biopsies were performed to reveal the metal constituents and concentrations. Histological analyses of the biopsies were performed with haematoxylin and eosin staining.Aims
Methods
C5 nerve root palsy is a rare and potentially
debilitating complication of cervical spine surgery. Currently,
however, there are no guidelines to help surgeons to prevent or
treat this complication. We carried out a systematic review of the literature to identify
the causes of this complication and options for its prevention and
treatment. Searches of PubMed, Embase and Medline yielded 60 articles
for inclusion, most of which addressed C5 palsy as a complication
of surgery. Although many possible causes were given, most authors supported
posterior
Severe spinal deformity in growing patients often requires surgical management. We describe the incidence of spinal deformity surgery in a National Health Service. Descriptive study of prospectively collected data. Clinical data of all patients undergoing surgery for spinal deformity between 2005 and 2018 was collected, compared to the demographics of the national population, and analyzed by underlying aetiology.Aims
Methods
Introduction. Iatrogenic spondylolisthesis occurs infrequently after posterior decompression. Posterior surgery is challenging due to altered anatomy and scarring. Anterior lumbar interbody fusion (ALIF) allows indirect decompression, restoration of lordosis and fusion. Material and Methods. Retrospective review of 6 patients (5 female, 1 male, mean age 64±5.8 years) with iatrogenic spondylolisthesis (5 L4/L5; 1 L4/L5) treated with stand-alone ALIF (Synfix, BMP2). Assessment of pelvic incidence, listhesis, pre- and post-operative ODI, VAS, global lumbar lordosis and segmental lordosis as outcome measurements. Results. The slippage was grade II at L4/L5 in 3 patients and grade I in 2 patients at L4/L5 and 1 patient at L5/S1. Average ODI dropped from 49±11% pre-operatively to 30±9% at 6 and to 25±6% at 12 months follow-up. VAS average dropped from 7±1 to 3±1 at 6 and 12 months follow-up. Average pelvic incidence was 54.6±8.0°. Global lordosis of 44.6±5.2° increased to 49.0±8.6°; Segmental lordosis in L4/5 was increased from 12.1±8.2° to 22.4±3.7° at 6 and 20.5±7.9° at 12 months. Cage
Aim. NICE guidance on lumbar total disc replacement (TDR) recommends ongoing audit should be an integral part of disc replacement surgery. We present our ongoing audit data and the extent of problem of patients lost to follow up. Method. 35 patients underwent lumbar TDR surgery over 4.5 years. They were followed prospectively. A database is maintained and ODI and VAS were collected prospectively, including patient satisfaction and any failures. Results. At latest follow up full data was available for 30 out of 35 patients. The mean follow-up was 34 months (range 3-52 months). There were 13 males with a mean age 37.7 years (range 27-62) and 17 females with a mean age of 49.8 years (range 27-62). Surgery was single level in 24 cases and double level in 6 cases. 21 patients rated their outcome as good or very good and 7 as unsatisfactory. There were 2 failures, one secondary to late extrusion of the polyethylene liner (12 months post-surgery) and one early anterior
Introduction. There is an unresolved controversy in the published work about the effect of screws crossing the neuro-central cartilage (NCC) on spinal canal dimension in very young children and in animals. Anterior vertebral body screws with fusion can invade and damage the NCC, especially at the site of screw insertion; however, this finding has never been studied. Methods. This study is a retrospective, clinical and radiological analysis of seven consecutive children aged 1–2 years treated with anterior vertebral instrumentation and fusion by downsized rod screw systems. The mean age at time of surgery was 2 years 4 months (range 1 year 9 months to 2 years 10 months). The average follow-up period was 3 years 3 months (2 years 6 months to 4 years 5 months). 16 screws inserted anteriorely were evaluated by a follow-up CT scan. Spinal canals were divided with known anatomical landmarks into right and left hemicanals. The relation of the anterior screws to the NCC and the spinal canal dimension were studied. All clinical and radiological complications were recorded. Results. Only 11 screws were suitable for measurement. There was a difference of 10–20% between the surface areas of the two hemicanals in six levels in which the screw heads were passing through or encroaching on the NCC; the canal was smaller ipsilateral to the affected NCC. The hemicanals were almost symmetrical in five levels in which the screw heads were away from the NCC, except in one in which it was touching the NCC. For the 16 screws evaluated there were no recorded complications apart from one screw breaching the adjacent end plate. Conclusions. Anterior vertebral body screws with fusion can encroach on the NCC when inserted in very young children, which seems to decrease the ipsilateral canal dimension between 10% and 20%. Apart from this finding, anterior instrumentation is safe when used in very young children aged 1–2 years. Canal asymmetry had no clinical effect in childhood; however, long-term follow-up of these children is needed to measure its clinical significance. Change of screw position with time is a frequent occurrence in the distal pedicle screws with single growing rods. There are two different types identified. With growing rods some degree of distal pedicle screw
HIV predisposes patients to opportunistic infections. However, with the establishment of Highly Active Anti-Retroviral Therapy (HAART), patients’ CD4 counts are maintained, as is a near normal life expectancy. This study aimed to establish the impact of HIV on the bacteriology of spondylodiscitis in a region in which tuberculosis (TB) is endemic, and to identify factors that might distinguish between them. Between January 2014 and December 2015, 63 consecutive cases of spontaneous spondylodiscitis were identified from a single-centre, prospectively maintained database. Demographics, presenting symptoms, blood results, HIV status, bacteriology, imaging, and procedure undertaken were reviewed and comparisons made of TB, non-TB, and HIV groups. There were 63 patients (22 male, 41 female) with a mean age of 42.0 years (11 to 78; Aims
Patients and Methods
Cement augmentation of pedicle screws could be used to improve screw stability, especially in osteoporotic vertebrae. However, little is known concerning the influence of different screw types and amount of cement applied. Therefore, the aim of this biomechanical A total of 54 osteoporotic human cadaver thoracic and lumbar vertebrae were instrumented with pedicle screws (uncemented, solid cemented or fenestrated cemented) and augmented with high-viscosity PMMA cement (0 mL, 1 mL or 3 mL). The insertion torque and bone mineral density were determined. Radiographs and CT scans were undertaken to evaluate cement distribution and cement leakage. Pull-out testing was performed with a material testing machine to measure failure load and stiffness. The paired Objectives
Materials and Methods
The aims of this study were to evaluate the clinical and radiological
outcomes of instrumented posterolateral fusion (PLF) performed in
patients with rheumatoid arthritis (RA). A total of 40 patients with RA and 134 patients without RA underwent
instrumented PLF for spinal stenosis between January 2003 and December
2011. The two groups were matched for age, gender, bone mineral
density, the history of smoking and diabetes, and number of fusion
segments. The clinical outcomes measures included the visual analogue scale
(VAS) and the Korean Oswestry Disability Index (KODI), scored before
surgery, one year and two years after surgery. Radiological outcomes
were evaluated for problems of fixation, nonunion, and adjacent
segment disease (ASD). The mean follow-up was 36.4 months in the RA
group and 39.1 months in the non-RA group.Aims
Methods