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The authors present a case of a spondylolisthesis with obvious foraminal stenosis on both sides as shown on the preoperative MRI. A proper operative technique in this case would include a restoration of disc height and the (partial) reduction of the slip. This technique would widen both foramina and no complication like opposite nerve root compression would occur. If reduction or disc height restoration cannot be achieved, decompression of both foramina should be performed. In mild cases a simple posterior distraction may be enough. In their paper the authors agree to this point as they write “decompression of the opposite side has not been judged necessary in the past as it has been commonly assumed that the TLIF spacer increases the disc space height and the foraminal height in the opposite foramen of the TLIF approach.” However, it seems that in the current case the authors failed to achieve restoration of disc height. Figure 7 shows differences between the preoperative and the postoperative CT scan of 1 mm (4 vs. 5 mm) and 1.5 mm (6.5 vs. 8 mm), respectively. The same is true for the “decrease” of foraminal height of 2 mm. I think that these measurements are not reliable since there is no calibration and no matching between the slices. Hence no obvious increase in disc height or decrease in foraminal height can be measured accurately. Anyway, the clinical significance of 1 or 2 mm of reduced foraminal height, if really present, seems to be questionable.

The concept of spinal instability is still controversial. Anatomical, biomechanical, clinical and radiographic variants are involved and make the definition complicated. There are solid diagnostic bases in cases of fractures and degenerative disorders; however, pure spinal instability is still under study. The latter may be defined as increased mobility that goes beyond the physiological limits of one vertebra over another in at least one of the three spinal planes of motion. In the case of the craniocervical region, its understanding becomes even more challenging, since its anatomy and physiology are more complex and it is more mobile. Surgical treatment is possible with either an anterior or a posterior approach. Best results are obtained with occipitocervical or atlantoaxial stabilization through a posterior approach, since the anterior one has its limitations. For example, a transoral approach with a bone graft provides compression strength but does not enable immediate appropriate fixation and involves the risk of infection. The choice of the surgical approach must consider the patient's medical status, the specific spine levels involved, the extent of neurological compromise, the X-ray abnormalities and the individual pathology. The goals of surgery are achieved through an appropriate anatomical alignment, assuring the protection of the neural elements and achieving proper spine stabilization with as much preservation of the mobile vertebral segments as possible.

Purpose Aim of this study was to compare the reconstruction of radiological sagittal spinopelvic parameters between lordotic (10°) and normal cages (0°) after dorsal lumbar spondylodesis. Methods This retrospective monocentric study included patients who received dorsal lumbar spondylodesis between January 2014 and December 2018. Inclusion criteria were degenerative lumbar diseases and mono- or bi-segmental fusions in the middle and lower lumbar region. Exclusion criteria were long-distance fusions (3 segments and more) and infectious and tumour-related diseases. The sagittal spinopelvine parameters (lumbar lordosis, segmental lordosis, sacral slope, pelvic incidence, and pelvic tilt) were measured pre- and post-operatively by two examiners at two different times. The patients were divided into 2 groups (group 1: lordotic cage, group 2: normal cage). Results One hundred thirty-eight patients (77 female, 61 male) with an average age of 66.6 ± 11.2 years (min.: 26, max.: 90) were included in the study based on the inclusion criteria. Ninety-two patients (66.7%) received 0° cages and 46 (33.3%) lordotic cages (10°). Segmental lordosis was increased by 4.2° on average in group 1 and by 6.5° in group 2 (p = 0.074). Average lumbar lordosis was increased by 2.1° in group 1 and by 0.6° in group 2 (p = 0.378). There was no significant difference in the correction of sagittal spinopelvic parameters. Inter- and inter-class reliability was between 0.887 and 0.956. Conclusion According to the results of our study, no advantages regarding sagittal radiological parameters for the implantation of a lordotic cage could be demonstrated.

Introduction Cellular bone matrices (CBM) are allograft products that provide three components essential to new bone formation: an osteoconductive scaffold, extracellular growth factors for cell proliferation and differentiation, and viable cells with osteogenic potential. This is an emerging technology being applied to augment spinal fusion procedures as an alternative to autografts. Methods We aim to compare the ability of six commercially‐available human CBMs (Trinity ELITE®, ViviGen®, Cellentra®, Osteocel® Pro, Bio4® and Map3®) to form a stable spinal fusion using an athymic rat model of posterolateral fusion. Iliac crest bone from syngeneic rats was used as a control to approximate the human gold standard. The allografts were implanted at L4‐5 according to vendor specifications in male athymic rats, with 15 rats in each group. MicroCT scans were performed at 48 hours and 6 weeks post‐implantation. The rats were euthanized 6 weeks after surgery and the lumbar spines were harvested for X‐ray, manual palpation and histology analysis by blinded reviewers. Results By manual palpation, five of 15 rats of the syngeneic bone group were fused at 6 weeks. While Trinity ELITE had eight of 15 and Cellentra 11 of 15 rats with stable fusion, only 2 of 15 of ViviGen‐implanted spines were fused and zero of 15 of the Osteocel Pro, Bio4 and Map3 produced stable fusion. MicroCT analysis indicated that total bone volume increased from day 0 to week 6 for all groups except syngeneic bone group. Trinity ELITE (65%) and Cellentra (73%) had significantly greater bone volume increases over all other implants, which was consistent with the histological analysis. Conclusion Trinity ELITE and Cellentra were significantly better than other implants at forming new bone and achieving spinal fusion in this rat model at week 6. These results suggest that there may be large differences in the ability of different CBMs to elicit a successful fusion in the posterolateral spine., We aim to compare the ability of six commercially‐available human CBMs (Trinity ELITE, ViviGen, Cellentra, Osteocel Pro, Bio4 and Map3) to form a stable spinal fusion using an athymic rat model of posterolateral fusion. Our results showed that Trinity ELITE and Cellentra were significantly better than other implants at forming new bone and achieving spinal fusion in this rat model at week 6.

Objective: This study aims to present the diagnostic characteristics of multimodal intraoperative monitoring (IOM) in spinal deformity surgery and to define and categorise the neuromonitoring events, as well as propose an algorithm of action. Materials and Methods: We reviewed 1,155 consecutive patients (807 female, 348 male) who underwent deformity correction using standardised perioperative care, cortical/cervical somatosensory evoked potentials (SSEPs), and upper/lower limb transcranial electrical motor evoked potential (MEPs) by a single surgeon. The mean age at surgery was 13.8 years (range 10–23.3). We categorised IOM events as true, transient true, and false positive or negative. Diagnostic performance criteria were calculated. Results: The most common diagnosis was adolescent idiopathic scoliosis in 717 (62%) patients. We identified 3 true positive monitoring events occurring in 2 patients (0.17%), 8 transient true positive (0.69%), and 8 transient false positive events (0.69%). There were no false negative events and no patient had postoperative neurological complications. The multimodal IOM technique had a sensitivity of 100%, specificity of 99.3%, positive predictive value of 55.6%, and negative predictive value of 100%. Sensitivity was 100% for MEPs and multimodal monitoring compared to 20% for cortical or cervical SSEPs. The frequency of true or transient true positive events was higher (p = 0.07) in Scheuermann’s kyphosis (3/91 patients, 3.3%) compared to adolescent idiopathic scoliosis (6/717 patients, 0.84%). Conclusion: Multimodal IOM is highly sensitive and specific for spinal cord injury. This technique is reliable for the assessment of the condition of the spinal cord during major deformity surgery. We propose an algorithm of intraoperative action to allow close cooperation between the surgical, anaesthetic, and neurophysiology teams and to prevent neurological deficits.

Summary of background dataThe skeletal system is affected in up to 60% of patients with neurofibromatosis type 1. The most commonly observed entities are spinal deformities and tibial dysplasia. Early recognition of radiologic osseous dystrophy signs is of utmost importance because worsening of the deformities without treatment is commonly observed and surgical intervention is often necessary. Due to the relative rarity and the heterogenic presentation of the disease, evidence regarding the best surgical strategy is still lacking.PurposeTo report our experience with the treatment of skeletal manifestations in pediatric patients with (neurofibromatosis type 1) NF-1 and to present the results with our treatment protocols.Materials and methodsThis is a retrospective, single expert center study on children with spinal deformities and tibial dysplasia associated with NF-1 treated between 2006 and 2020 in a tertiary referral institution.ResultsSpinal deformity:Thirty-three patients (n = 33) were included. Mean age at index surgery was 9.8 years. In 30 patients (91%), the deformity was localized in the thoracic and/or lumbar spine, and in 3 patients (9%), there was isolated involvement of the cervical spine. Eleven patients (33%) received definitive spinal fusion as an index procedure and 22 (67%) were treated by means of “growth-preserving” spinal surgery. Halo-gravity traction before index surgery was applied in 11 patients (33%). Progression of deformity was stopped in all patients and a mean curve correction of 60% (range 23–98%) was achieved. Mechanical problems with instrumentation requiring revision surgery were observed in 55% of the patients treated by growth-preserving techniques and in none of the patients treated by definitive fusion. One patient (3%) developed a late incomplete paraplegia due to a progressive kyphotic deformity.Tibial dysplasia:The study group comprised of 14 patients. In 5 of them (36%) pathological fractures were present on initial presentation. In the remaining 9 patients (64%), anterior tibial bowing without fracture was observed initially. Four of them (n = 4, 28%) subsequently developed a pathologic fracture despite brace treatment. Surgical treatment was indicated in 89% of the children with pathological fractures. This involved resection of the pseudarthrosis, autologous bone grafting, and intramedullary nailing combined with external fixation in some of the cases. In 50% of the patients, bone morphogenic protein was used “off-label” in order to promote union. Healing of the pseudarthrosis was achieved in all of the cases and occurred between 5 to 13 months after the index surgical intervention. Four of the patients treated surgically needed more than one surgical intervention in order to achieve union; one patient had a re-fracture. All patients had a good functional result at last follow-up.ConclusionEarly surgical intervention is recommended for the treatment dystrophic spinal deformity in children with NF-1. Good and sustainable curve correction without relevant thoracic growth inhibition can be achieved with growth-preserving techniques alone or in combination with short spinal fusion at the apex of the curve. Preoperative halo-gravity traction is a safe and very effective tool for the correction of severe and rigid deformity in order to avoid neurologic injury. Fracture union in tibial dysplasia with satisfactory functional results can be obtained in over 80% of the children by means of surgical resection of the pseudarthrosis, intramedullary nailing, and bone grafting. Wearing a brace until skeletal maturity is achieved is mandatory in order to minimize the risk of re-fracture.

Introduction: Neuromuscular scoliosis leads to a wide range of spinal disorders which disturb the musculoskeletal system. The aim of this study is to compare the clinical and radiological results of posterior spinal fusion with and without extending the instrumentation to iliac bones in treatment of neuromuscular scoliosis. Methods: Medical records and radiographies of 36 patients with neuromuscular scoliosis who underwent posterior instrumentation between 2011 and 2015 were reviewed. Age and body mass index at time of surgery, underlying diagnosis, gender, postoperative infection rates, perioperative and postoperative blood transfusion, duration of surgery, complication rates were identified for each patient retrospectively. SF-36 physical questionnaire was applied to all patients. Surgery was performed in each patient and included posterior spinal fusion with pedicle screws from the proximal thoracic spine (T2 or T3) to S1 (Group A) or extension of distal instrumentation to pelvis by bilateral iliac screws (Group B). Results: A total of 23 patients in group A were compared with 13 patients in group B. Median age was 14 (9–38) years for group A and 16 (12–25) years for group B. Median follow-up period was 20 (12–66) months. Preoperative median Cobb angles were 66° and 60° and postoperative Cobb values were 33° and 31° in group A and B respectively. Median Cobb angle reduction was 40° and 34° for group A and B. We are able to see in this study that the usage of illiac screws do not increase implant failure and help achieve better functional results. Conclusion: This study shows that the extention of instrumentation to the pelvis with illiac screws can be beneficial in terms of functional and complicational incidences.Level of evidence: Level III, therapeutic study. Keywords: Neuromuscular scoliosis, Iliac fixation, Pelvic fixation, Blood loss, Neuromuscular disease

Objective: The aim of this study was to evaluate preoperative and postoperative spinopelvic parameters and the influence of lowest instrumented vertebrae on sagittal parameters in Lenke 5 Adolescent Idiopathic Scoliosis (AIS) patients. Methods: A total of 42 patients (37 females, 5 males; mean age: 16.71 ± 3.46 years) were included in the study. Preoperative and postoperative last follow up lumbar lordosis (LL), thoracic kyphosis (TK), pelvic tilt (PT), pelvic incidence (PI) and sacral slope (SS) angles measured. By stopped fusion in L3, L4 or L5 we divided the group into three parts. Results: Mean follow-up was 43 months. Preoperatively, the mean TK and LL were 36.8° and 55.3°. At the last follow up, the mean TK and LL were 27.1° and 49.0° degrees, respectively. Preoperatively, the mean PI, PT and SS were 53.3°, 16.1° and 37.4° degrees. At the last follow up, the mean PI, PT and SS were 52.7°, 19.9° and 33.0° respectively. Significant differences were observed for SS (p = 0.003), TK (p = 0.004), LL (p = 0.012) and PT (p = 0.013) postoperatively for all patients. According the L3 and L4 groups there is significant difference in SS, LL (p = 0.013) and PT (p = 0.018) which means a significant decrease occurs in SS and LL when the distal fusion level changes from L3 to L4 but significant increase in PT in L3 group to compensate spinopelvic change after surgery. Conclusion: The selection of more distal level for fusion adversely affects the compensation mechanisms of sagittal balance in Lenke 5 AIS patients. Level of Evidence: Level IV, Therapeutic study. Keywords: Lenke 5, Scoliosis, Sagittal, Spinopelvic, Compensate

// Zunpeng Liu 1, 2 , Yue Zhu 1 , Rui Ge 3 , Jiajun Zhu 2 , Xiaoning He 4 , Xue Yuan 5 and Xinchun Liu 1 1 Department of Orthopedics, First Affiliated Hospital, China Medical University, Shenyang, China 2 Department of Orthopedics, Fourth Affiliated Hospital, China Medical University, Shenyang, China 3 Department of Orthopedics, First Affiliated Hospital, Dalian Medical University, Dalian, China 4 Department of Stomatology, Fourth Affiliated Hospital, China Medical University, Shenyang, China 5 Division of Plastic and Reconstructive Surgery, Department of Surgery, Stanford School of Medicine, Stanford, CA, USA Correspondence to: Yue Zhu, email: zhuyuedr_cmu1h@126.com Keywords: BMSC, PRP, rabbit posterolateral spinal fusion, osteogenic ability, fusion rate Received: March 29, 2017 Accepted: June 01, 2017 Published: July 31, 2017 ABSTRACT Bone tissue engineering provides a substitute for bone transplantation in spinal fusion. This study examined if combined bone marrow-derived mesenchymal stem cells (BMSCs) sheet with platelet-rich plasma (PRP) could promote bone regeneration in a rabbit posterolateral spinal fusion model. BMSCs was isolated and confirmed by Flow cytometric analysis and immunofluorescence staining. The morphology of BMSCs was examined by Hematoxylin and Eosin staining, scanning and transmission electron microscopy. BMSCs were cultured in induction medium or control medium. The osteogenic ability of BMSCs was investigated by various histochemical staining, immunofluorescence staining and qRT-PCR analysis. The BMSCs/PRP was constructed by encapsulating the PRP block with BMSCs sheet. Twenty-four adult rabbits were randomly divided into four groups based on the implanted biomaterials: BMSCs/PRP, BMSCs, iliac crest autograft, and control group. Manual palpation and digital radiography analysis showed that the fusion rate was 100%, 0, 83.3%, and 0 in these 4 groups, respectively. Formation of continuous bone masses in BMSCs/PRP group was confirmed by computed tomography scanning and 3D-reconstruction. These studies demonstrated that BSMCs/PRP significantly accelerated bone regeneration in the rabbit posterolateral spinal fusion model.

Autogenous bone graft is the best for spinal fusion in clinics, however, lacking sources, bleeding and infection are limited its practice. Seeking alternative materials are urgent for orthopaedic surgeon. Here, we evaluated osteoblast-oriented differentiation of rabbit BMSCs by co-culturing with composite scaffolds constructed using silicon-substituted-CaP-fine particulate bone powder-alginate. Using CCk8-kit, biocompatibility was evaluated by testing BMSCs proliferation; morphology and survival of osteoblasts within scaffolds were observed using EM and HE staining; growth factors and related genes were detected using RT-PCR. HE staining showed spindle-shaped BMSCs after the 3rd passage; EM data showed that uneven surface and longitudinal section were observed with scattered distribution of 5-100 mm interspaces, which leave enough space for BMSCs adhesion and growth. Interestingly, at 14-day culture with HE staining, osteocytes within the scaffolds grew well with regular shape and integrate structure. RT-PCR results showed that expression levels of BMP2, TGF-b and COL-I, ALP, OPN were increased significantly and time-dependently. Collectively, all mentioned effects were more obvious in co-culture BMSCs with scaffolds than those with other components. Immunohistochemistry showed that positive OPN expression was detected at 7-day co-culturing BMSCs with scaffold, rather than other situations. These results suggest that composite scaffolds constructed with Si-CaP-fine particulate bone powder-alginate have a certain degree of biocompatibility and bioactivity to promote osteoblast-oriented BMSCs differentiation.

Purpose To access the feasibility and efficacy of percutaneous endoscopic debridement (PED) combined with percutaneous pedicle screw fixation (PPSF) in the treatment of lumbar pyogenic spondylodiscitis. Methods Forty-five patients diagnosed as pyogenic spondylodiscitis underwent PPSF followed by PED. A drainage catheter was left in place for negative pressure drainage. Adequate systematic antibiotics were administered empirically or based on bacterial culture results. Clinical outcomes were assessed by physical examination, regular serologic testing, visual analog scale (VAS), Oswestry Disability Index (ODI), and imaging studies. Results The mean operative time was 110.1 ± 21.2 minutes (range 80–165 minutes), with intra-operative blood loss 47.8 ± 21.0 ml (range 20–120 ml). All patients reported relief of back pain, able to sit up, and partially ambulate the next day. Causative pathogens were identified in 32 of 45 biopsy specimens, staphylococcal bacteria being the most prevalent strain. However, there were 13 patients with post-operative complications. During 6–12 months’ follow-up, inflammatory markers showed infection controlled. VAS and ODI values were significantly improved. Discussion Satisfactory clinical and functional outcomes were achieved in our patients post-operatively. It is recommended that PED plus PPSF can be another alternative for spondylodiscitis. Conclusion PED supplementing PPSF offers a valid option in treating spondylodiscitis, as it is minimally invasive, shortens hospital stay, and avoids prolonged bed rest with an optimistic outcome.

Objective: Congenital heart disease (CHD) is associated with the development of scoliosis. Improvements in cardiac care have extended survival of children with cyanotic CHD which possess a need for correction of scoliosis. There is limited information on spinal care for these patients. We present 3 patients with CHD who underwent surgical correction of scoliosis. Materials and Methods: We reviewed demographic and clinical data on patients with cyanotic CHD. Results: Patient 1 underwent posterior spinal fusion T3–L3 at the age of 16 years. He had a double inlet left ventricle and was treated with completion of a Fontan circulation. Hypotensive anaesthesia was used but he lost 3,000 mL of blood. The operative time was 370 min and most of the blood loss occurred in the second half of the procedure. Patient 2 underwent posterior spinal fusion T5–T12 when aged 14 years. She had transposition of the great vessels corrected over multiple surgeries. Hypotensive anaesthesia was used, she had blood loss of 300 mL, and the surgical time was 282 min. Patient 3 underwent posterior spinal fusion extending from T5–T12 when he was 17 years old. He had a double inlet left ventricle and was treated with completion of a Fontan circulation. Hypotensive anaesthesia was used, he had blood loss of 1,021 mL, and a surgical time of 342 min. Conclusion: Scoliosis surgery in patients with complex cardiac disease may be indicated to treat progressive deformities which produce severe symptoms. A multidisciplinary approach including a spinal surgeon as well as a cardiologist, haematologist, respiratory paediatrician, and spinal anaesthetist can evaluate the general medical condition and weigh the benefits and risks of surgery. Deformity correction can be performed using a meticulous technique and has produced a series of satisfactory outcomes.

Introduction : Midline lumbar fusion (MIDLF) using cortical bone trajectory is an alternative method of transpedicular spinal fusion for degenerative disease. The new entry points’ location and screwdriving direction allow the approach-related morbidity to be reduced. Aim: To present our preliminary experience with the MIDLF technique on the first 5 patients with lumbar degenerative disease and with follow-up of at least 6 months. Material and methods: Retrospective analysis was performed on the first 5 patients with foraminal (4) or central (1) stenosis operated on between December 2014 and February 2015. Three patients were fused at L4–L5 and two at the L5–S1 level. Results: No intra- or post-operative complications occurred with this approach. An improvement regarding the leading symptom in the early postoperative period (sciatica 4/4, claudication 1/1) was achieved in all patients. The mean improvements in the visual analogue scale for low back and leg pain were 2.2 and 4.8 respectively. The mean Oswestry Disability Index scores were 52% (range: 16–82%) before surgery and 33% (range: 12–56%) at 3-month follow-up (mean improvement 19%). At the most recent follow-up, 4 patients reported the maintenance of the satisfactory result. The early standing and follow-up X-rays showed satisfactory screw placement in all patients. Conclusions : In our initial experience, the MIDLF technique seems to be an encouraging alternative to traditional transpedicular trajectory screws when short level lumbar fusion is needed. Nevertheless, longer observations on larger groups of patients are needed to reliably evaluate the safety of the method and the sustainability of the results.

Introduction: Patients suffering from degenerative scoliosis curves often present with radicular symptoms mainly on the concave side of their curves. Standard treatment includes posterior decompressions, followed by fusions. These procedures carry large morbidity rates. We have observed resolution of radicular and stenotic symptoms with Direct Lateral Interbody Fusions (DLIF). Aim: In this study we radiographically assess indirect decompression effect of DLIF procedure. Methods: We conducted a case series of four patients with 2-stage procedures. All patients presented with back pain and leg symptoms. Stage one included the insertion of the DLIF polyetheretherketone cages and rh-BMP2. This was followed by a second stage posterior fixation utilizing percutaneous pedicle screws and rods. Plain radiographs were utilized to determine the concave and convex sides of the scoliosis. Pre- and post-DLIF measurements were made from axial and sagittal MRIs. Measurements included central, subarticular, and foraminal areas. Statistical significance was estimated via paired sample t-test. Results: All patients had complete resolution of leg symptoms with remarkable improvement in all areas measured. When both concave and convex sides of the curve are considered, an increase of 49% in the central canal, 82% in the subarticular area, and 71% in the foraminal area was measured. When only the concave levels were measured, there was a 90% increase (0.22 cm2 vs. 0.41 cm2) in the subarticular area and 77% (0.46 cm2 vs. 0.81 cm2) increase in the foraminal area (p < .001). Conclusion: The DLIF procedure provides an indirect decompression of the neural elements along with its role in spinal fusion. This negates the need for posterior decompression surgery in degenerative scoliosis associated with spinal stenosis, which might lead to less blood loss and surgical time in these complex surgeries.

Introduction: Scoliosis could develop at the childhood age and progress beyond skeletal maturity. An early spinal fusion arrests growth of the spine and thorax, risking the development of secondary thoracic insufficiency syndrome. Vertical expandable prosthetic titanium rib (VEPTR) is a fusionless technique aiming to correct the deformity with preservation of growth potential. Aim: To show our experience and results regarding the use of VEPTR in children with scoliosis in regard to coronal profiles(length and deformity angle), spinal growth, and the complications we faced during the follow-up of two years after the index procedure. Methods: A retrospective analysis of prospectively collected data of a case series. Forty child with scoliosis of different etiologies. Their primary diagnoses were neuromuscular scoliosis in 13, Juvenile idiopathic scoliosis in12, Congenital Scoliosis in 8, syndromatic patients 5 and 2 with Arthrogryposis. All 40 patients received percutaneous rib-to-pelvis or rib to vertebra or rib to rib VEPTR implantation between January 2016 and January 2018. None of them needed blood transfusion. They underwent 56 primary implantation, 16(40%) bilateral system and 24(60%) unilateral followed by lengthening procedure in a period of 4-6 months. The patients were assessed based on mechanical measures, that is, the radiographic improvement of their scoliosis, spinal height, and sagittal and coronal correction, which are measured and compared preoperatively, immediately postoperatively and at two years follow up, complication encountered during this period are also counted. Results: The average initial correction in Cobb angle immediately after the index surgery was 14.4° (5°-26°) and the average final correction of Cobb which is measured after the last expansion procedure (Cobb angle of the major curve measured after last expansion minus initial preoperative Cobb angle of the major curve) was 7.3° (12%). The average of preoperative coronal T1-S1 length was 25.6 cm with an average initial correction achieved immediately after implantation of VEPTR of2.8 cm (1.2-5.1cm) which is 10.9%, and the average coronal length gain at 2 years follow up was 5.7 cm (3.7-9.8cm) that is 22.2%. Complication occurred in 18 of our patients (45%). Conclusion: Early results of VEPTR for childhood scoliosis are encouraging. Follow-up till skeletal maturity will best determine future indications.

A wide range of materials have been used for the development of intervertebral cages. Poly(propylene fumarate) (PPF) has been shown to be an excellent biomaterial with characteristics similar to trabecular bone. Hydroxyapatite (HA) has been shown to enhance biocompatibility and mechanical properties of PPF. The purpose of this study was to characterize the effect of PPF augmented with HA (PPF:HA) and evaluate the feasibility of this material for the development of cervical cages. PPF was synthesized and combined with HA at PPF:HA wt:wt ratios of 100:0, 80:20, 70:30, and 60:40. Molds were fabricated for testing PPF:HA bulk materials in compression, bending, tension, and hardness according to ASTM standards, and also for cage preparation. The cages were fabricated with and without holes and with porosity created by salt leaching. The samples as well as the cages were mechanically tested using a materials testing frame. All elastic moduli as well as the hardness increased significantly by adding HA to PPF (p

Current implant materials and designs used in spinal fusion show high rates of subsidence. There is currently a need for a method to predict the mechanical properties of the endplate using clinically available tools. The purpose of this study was to develop a predictive model of the mechanical properties of the vertebral endplate at a scale relevant to the evaluation of current medical implant designs and materials. Twenty vertebrae (10 L1 and 10 L2) from 10 cadavers were studied using dual-energy X-ray absorptiometry to define bone status (normal, osteopenic, or osteoporotic) and computed tomography (CT) to study endplate thickness (μm), density (mg/mm3), and mineral density of underlying trabecular bone (mg/mm3) at discrete sites. Apparent Oliver–Pharr modulus, stiffness, maximum tolerable pressure (MTP), and Brinell hardness were measured at each site using a 3 mm spherical indenter. Predictive models were built for each measured property using various measures obtained from CT and demographic data. Stiffness showed a strong correlation between the predictive model and experimental values (r = 0.85), a polynomial model for Brinell hardness had a stronger predictive ability compared to the linear model (r = 0.82), and the modulus model showed weak predictive ability (r = 0.44), likely due the low indentation depth and the inability to image the endplate at that depth (≈0.15 mm). Osteoporosis and osteopenia were found to be the largest confounders of the measured properties, decreasing them by approximately 50%. It was confirmed that vertebral endplate mechanical properties could be predicted using CT and demographic indices.

Both percutaneous endoscopic lumbar discectomy (PELD) and minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) have been demonstrated as two common and effective choices for lumbar disc herniation (LDH) minimally invasive surgery. In order to get a better understanding of these two procedures, we made this contrastive review. By looking up recent literature and combining it with our clinical practice, the indications/contraindications, advantages/disadvantages as well as complications/recurrences of PELD and MIS-TLIF were summarized in this review. It was concluded that PELD and MIS-TLIF are safe and effective minimally invasive operative techniques for symptomatic LDH treatment. A better understanding of these two procedures will help to improve clinical outcomes by selecting proper indications, and also benefit the further development of minimally invasive spine surgery.

ObjectiveThe purpose of this study was to investigate whether a simple, biologically robust method for inducing calcification of degenerate intervertebral discs (IVD) could be developed to provide an alternative treatment for patients requiring spinal fusion.DesignNucleus pulposus (NP) cells isolated from 14 human IVDs were cultured in monolayer and exposed to osteogenic medium, 1,25-dihydroxyvitamin D3(VitD3), parathyroid hormone (PTH), and bone morphogenic proteins (BMPs) 2/7 to determine if they could become osteogenic. Similarly explant cultures of IVDs from 11 patients were cultured in osteogenic media with and without prior exposure to VitD3and BMP-2. Osteogenic differentiation was assessed by alkaline phosphatase activity and areas of calcification identified by alizarin red or von Kossa staining. Expression of osteogenic genes during monolayer culture was determined using polymerase chain reaction and explant tissues assessed for BMP inhibitors. Human bone marrow–derived mesenchymal stromal cells (MSCs) were used for comparison.ResultsStandard osteogenic media was optimum for promoting mineralization by human NP cells in monolayer. Some osteogenic differentiation was observed with 10 nM VitD3, but none following application of PTH or BMPs. Regions of calcification were detected in 2 of the eleven IVD tissue explants, one cultured in osteogenic media and one with the addition of VitD3and BMP-2.ConclusionsHuman NP cells can become osteogenic in monolayer and calcification of the extracellular matrix can also occur, although not consistently. Inhibitory factors within either the cells or the extracellular matrix may hinder osteogenesis, indicating that a robust biological fusion at this time requires further optimization.

BACKGROUND: Internet use within health care contexts offers the possibility to provide both health information and peer support. Internet Support Groups (ISGs) for patients may offer advantages, which are not found in face-to-face support. In patients undergoing lumbar spine fusion (LSF), ISGs could have a particular potential, as peer support on the web might bridge the decreased satisfaction with social life and social isolation found within these patients. ISGs might in this way contribute to increasing the functioning and overall health-related quality of life. However, LSF patients may generally belong to a group of citizens not prone to internet and online peer support. However, our knowledge of how LSF patients use ISGs is limited.OBJECTIVE: The aim of this study was to describe the characteristics of users of an ISG and thematically explore the content of ISG interactions in Danish patients undergoing instrumented LSF because of degenerative spine disorders.METHODS: Participants were recruited from a randomized controlled trial and included in a prospective cohort with a mixed methods design. Sociodemographic characteristics and information on psychological well-being (symptoms of anxiety and depression) were obtained at baseline and 1 to 5 weeks before surgery. Usage of the ISG was registered from baseline until 3 months after surgery. All posts and comments were collected, and content analysis was performed.RESULTS: A total of 48 participants comprised the study population, with a mean age of 53 years (range 29-77). Of the participants, 54% (26/48) were female, 85% (41/48) were cohabitating, 69% (33/48) were unemployed, and the majority (69% [33/48]) had secondary education. Approximately one-third of the participants had symptoms of depression (35%, 17/48) and anxiety (29%, 14/48). Overall, 90% (43/48) of the participants accessed the ISG. No correlations were found between sociodemographic characteristics and access to the ISG. Women were more prone to be active users, contributing with posts (P=.04). Finally, active users contributing with posts or comments had viewed more pages, whereas passive users, users without posts or comments, had more interactions with the ISG (PCONCLUSIONS: Sociodemographic characteristics were not predictors of ISG use in this study, and active use was found to be gender dependent. Content of interactions on the ISG emerged within 7 thematic categories and focused on social recognition, experience of pain or use of pain medication, experience of physical activity or physical rehabilitation, expression of psychosocial well-being, advising on and exploring the ISG, and employment, which seemed to correspond well with the prevalent occurrence of symptoms of anxiety and depression.

This position paper summarises a vision of how cell-based therapies can be applied clinically to regenerate bone, as well as the steps needed to narrow the gap between that vision and clinical reality. It is a result of the presentations and discussion of the “Cell Therapy for Bone Repair” breakout session at the AO Foundation Symposium “Where Science Meets Clinics” in Davos, Switzerland from September 5-7, 2013. Participants included leaders from science, medicine, and industry from around the world. The session included clinical and scientific presentations, as well as an extended discussion among participants. Bone tissue has an innate regenerative capacity that in most cases allows functional healing at damage sites. However, there are a number of serious conditions in which bone does not fully heal and the result is significant morbidity. The clinical need for new therapies is clear, and the breakout session participants were enthusiastic about the potential impact on cell-based therapies for bone repair in the clinic. However, they also recognised the significant challenges that face the development of commercially viable cell therapy products. This paper outlines a vision in which patient selection is based on expected therapeutic outcome to create a consistently successful, cost-effective, cell-based therapy for bone repair. The need for a more complete understanding of bone repair, a better infrastructure for preclinical studies, and the need for collaboration among stakeholders is discussed.

There is a need to better understand the effects of intervertebral spacer material and design on the stress distribution in vertebral bodies and endplates to help reduce complications such as subsidence and improve outcomes following lumbar interbody fusion. The main objective of this study was to investigate the effects of spacer material on the stress and strain in the lumbar spine after interbody fusion with posterior instrumentation. A standard spacer was also compared with a custom-fit spacer, which conformed to the vertebral endplates, to determine if a custom fit would reduce stress on the endplates. A finite element (FE) model of the L4–L5 motion segment was developed from computed tomography (CT) images of a cadaveric lumbar spine. An interbody spacer, pedicle screws, and posterior rods were incorporated into the image-based model. The model was loaded in axial compression, and strain and stress were determined in the vertebra, spacer, and rods. Polyetheretherketone (PEEK), titanium, poly(para-phenylene) (PPP), and porous PPP (70% by volume) were used as the spacer material to quantify the effects on stress and strain in the system. Experimental testing of a cadaveric specimen was used to validate the model's results. There were no large differences in stress levels (37%) the stress at the bone–spacer interfaces for all materials tested. A 28% decrease in stress was found in the posterior rods with the custom spacer. Of all the spacer materials tested with the custom spacer design, 70% porous PPP resulted in the lowest stress at the bone–spacer interfaces. The results show the potential for more compliant materials to reduce stress on the vertebral endplates postsurgery. The custom spacer provided a greater contact area between the spacer and bone, which distributed the stress more evenly, highlighting a possible strategy to decrease the risk of subsidence.

Background The main goal of treatment in early-onset scoliosis is to obtain and maintain curve correction while simultaneously preserving spinal, trunk, and lung growth. This study introduces a new surgical strategy, called the modified growing rod technique, which allows spinal growth and lung development while controlling the main deformity with apical and intermediate anchors without fusion. The use of intraoperative traction at the initial procedure enables spontaneous correction of the deformity and decreases the need for forceful correction maneuvers on the immature spine and prevents possible implant failures. This study seeks to evaluate (1) curve correction; (2) spinal length; (3) number of procedures performed; and (4) complications with the new approach.

The objective of this paper was to investigate the surgical strategy of the selection of the lowest instrumented vertebrae (LIV) in anterior correction for adolescent idiopathic scoliosis (AIS) and to discuss the relationship between the LIV and trunk balance. From 1998 to 2004, 28 patients with thoracolumbar/lumbar AIS (Lenke 5 type) were treated by anterior correction and fusion with a mean follow-up of 1.5 years. Specific radiographic parameters were observed respectively and the correlation between disc wedging immediately below the LIV and these parameters was analysed. The mean corrective rate of major curves was 74.84%. The preoperative disc angle distal to LIV was 2.96 +/- 1.43 degrees and postoperatively it was -3.60 +/- 1.75 degrees . The postoperative disc wedging was most correlated with LIV obliquity. The postoperative LIV-CSVL (centre sacral vertical line) distance, which reflects regional balance, was correlated with various preoperative parameters. LIV determination was correlated with multiple preoperative radiographic parameters. Disc wedging distal to LIV occurs most often when a short fusion excluding the lower end vertebra (LEV) and the subjacent disc are nearly parallel.

It is not uncommon for patients to undergo less invasive spine surgery (LISS) prior to succumbing to lumbar fusion; however, the effect of failed LISS on subsequent fusion outcomes is relatively unknown. The aim of this study was to test the hypothesis that patients who suffered failed LISS would afford inferior subsequent fusion outcomes when compared to patients who did not have prior LISS.After IRB approval, registry from a spine surgeon was queried for consecutive patients who underwent fusion for intractable low back pain. The 47 qualifying patients were enrolled and split into two groups based upon a history for prior LISS: a prior surgery group (PSG) and a non-prior surgery group (nPSG).Typical postoperative outcome questionnaires, which were available in 80.9% of the patients (38/47) at an average time point of 40.4 months (range, 13.5-66.1 months), were comparatively analysed and failed to demonstrate significant difference between the groups, e.g. PSG v. nPSG: ODI--14.6 ± 10.9 vs. 17.2 ± 19.4 (P = 0.60); SF12-PCS--10.9 ± 11.0 vs. 8.7 ± 12.4 (p = 0.59); bNRS--3.0 (range -2-7) vs. 2.0 (range -3-8) (p = 0.91). Patient satisfaction, return to work rates, peri-operative complications, success of fusion and rate of revision surgery were also not different.Although limited by size and retrospective design, the results of this rare investigation suggest that patients who experience a failed LISS prior to undergoing fusion will not suffer inferior fusion outcomes when compared to patients who did not undergo prior LISS.