In this paper, the authors propose classifying the epiphenomenon of spinal deformity in two different categories: structural deformity, when the main driver of the observed deformity is a fixed and stiff alteration of the spinal segments, and compensatory deformity, which includes cases where the observed deformity is due to focal abnormalities. This last category comprises, but is not limited to, spinal stenosis, spondylolisthesis, disc herniation, infection or tumor, hip disease or neurological disease (such as Parkinson’s disease).
Method
Narrative review article.
Results
We analyzed the focal diseases of the spine that may cause a compensatory deformity inducing adaptation in the unaffected part of the spine.
Conclusion
The compensatory mechanisms involved in adaptive deformity represent an attempt to maintain a global alignment, to escape from pain or to control body posture.
Graphical abstract
These slides can be retrieved under Electronic Supplementary material.
To compare long term clinical and radiographic outcomes in osteoporotic vertebral compression fractures of the thoracolumbar spine treated with conservative treatment and percutaneous vertebroplasty.
Methods
The retrospective study with inclusion criteria focused on osteoporotic fractures of the thoracolumbar junction (T10–L2). Clinical outcomes were evaluated by using the VAS, Oswestry and SF36 questionnaires. Radiographic outcomes were evaluated by comparing the following sagittal parameters: body angle, sagittal index of fractured vertebral body and adjacent vertebral segments kyphosis. Complications in terms of adjacent vertebral fractures and cement leakage are reported.
Results
Percutaneous vertebroplasty provided better vertebral body height restoration, but was associated with a higher incidence of adjacent fractures (20%) than conservative treatment (3.5%). This fact may explain why patients treated with percutaneous vertebroplasty had worse overall kyphotic alignment at final follow-up. Cement leakage was frequent, but always asymptomatic and generally no serious complications occurred.
Conclusions
Percutaneous vertebroplasty represents a safe treatment for osteoporotic vertebral compression fractures, although it may be associated with a higher incidence of adjacent fractures and therefore worse thoracolumbar kyphosis and long-term follow-up than conservative treatment.
Graphical abstract
These slides can be retrieved under Electronic Supplementary Material.
The purpose of this study was to examine whether Hounsfield units (HUs), as an alternative bone mineral density measurement to dual-energy X-ray absorptiometry and quantitative computed tomography, which lead to additional radiation exposure for patients, has an effect on the maintenance of reduction in bisegmental Cobb angle (CA) and cage subsidence in patients who receive bisegmental spine stabilization after traumatic thoracolumbar spine fractures.
Methods
A total of 81 patients with a mean follow-up of 12 months were analyzed. CAs and cage subsidence were measured intraoperatively and at follow-up. HU was measured, and patients were subsequently assigned based on HU to three HU subgroups (group 1: HU?<?110 [poor bone quality (BQ)]; group 2: HU 180–110 [diminished BQ]; group 3: HU?>?180 [good BQ]).
Results
Following anterior stabilization, loss of reduction and cage subsidence differed between patients with poor and diminished BQ but not significantly, and both groups showed significantly more loss of reduction and cage subsidence than patients with good BQ.
Conclusion
BQ, estimated with HU, had significant effects on cage subsidence and loss of reduction. We recommend measuring HU before surgery and applying additional treatment strategies, such as polymethylmethacrylate augmentation of endplates or anterior plates, for patients with HU?<?180.
Graphical abstract
These slides can be retrieved under Electronic Supplementary Material.
To use radiofrequency ablation (RFA) in the resection of C4 cervical chordoma with a giant paravertebral tumor mass to achieve tumor-free exposed margins and perform a gross total excision.
Methods
A gross total excision using combined posterior and anterior approaches was performed. In the posterior stage, the C4 posterior arch was removed and the C4/C5 nerve roots and vertebral artery were released from the tumor. In the anterior stage, the giant soft mass of tumor from C3 to C6 was treated with RFA to make it shrink and solidify visually to achieve tumor-free exposed margins before resecting the tumor. Finally, a gross total excision was performed followed by the implantation of titanium plate and mesh filled with allograft bone.
Results
A gross total excision was performed with tumor-free exposed margins and radiotherapy. The patient survived more than 5 years without recurrence.
Conclusions
RFA can help achieve tumor-free exposed margins. A gross total excision combined with RFA can improve the local relapse-free survival of patients with cervical chordoma.
Graphical abstract
These slides can be retrieved under Electronic Supplementary Material.
To present a classification system for vertebral body osteonecrosis (VBON) based on imaging findings and sagittal alignment and consequently to propose treatment guidelines.
Methods
Chart review and classification of imaging and clinical findings. An analysis of literature about VBON has been evaluated to conceive the classification. The current data allows to correlate radiological findings with different stages of the pathophysiological process and consequently to propose a patient-tailored treatment plan.
Results
The classification identifies 4 stages: stage 0 (theoretical phase), stage 1 (early phase), stage 2 (instability phase) and stage 3 (fixed deformity phase). Local (angular kyphosis expressed as anterior–posterior wall height ratio) and global (sagittal vertical axis and pelvic tilt) sagittal alignment are considered as complementary modifiers to tailor the most suitable treatment. Stage 1 is generally managed conservatively. Stage 2 and 3 often require different surgical approaches according to local and global sagittal alignment.
Conclusions
The classification allows a systematic staging of this disease and can help establish a proper and patient-oriented treatment plan. Further researches are advocated to fully validate the proposed classification system.
Graphical abstract
These slides can be retrieved under Electronic Supplementary Material.
To define if MRI scans can accurately be requested based on information provided in the primary care referral and, therefore, streamline the patient journey.
Summary of background data
The demand for outpatient spinal appointments significantly exceeds our services’ ability to provide efficient, high-quality patient care. Currently, magnetic resonance imaging (MRI) of the spine is requested following first consultation.
Methods
During routine vetting of primary care referral letters, three consultant spinal surgeons recorded how likely they thought each patient would be to have an MRI scan. Following the first consultation with the spinal service, the notes of each patient were reviewed to see if an MRI was requested. We measured the positive predictive value (PPV), negative predictive value (NPV), sensitivity and specificity of ordering MRI scans based on primary care referral letters.
Results
149 patients were included [101 females, 48 males, mean age 49 (16–87)]. There were 125 routine, 21 urgent, and 3 ‘urgent-suspected cancer’ referrals. The PPV of ordering MRIs before first consultation was 84%, NPV was 56% with the sensitivity and specificity being 82 and 59%, respectively. Ordering MRIs during initial vetting could shorten the patient journey with potential socioeconomic benefits.
Conclusions
MRI scans can be effectively ordered based on the information provided by the primary care referral letter. Requesting MRI scans early in the patient journey can save considerable time, improve care, and deliver cost savings.
Graphical abstract
These slides can be retrieved under Electronic Supplementary Material.
Post-operative infections are relatively common after posterior spine surgery, and there are several observations reflecting different infection complications related to various metals implanted. Here, we selected an array of different bacterial species that are often found in infections associated with orthopaedic implants and tested for inhibition by hydrogen peroxide-treated titanium (Ti-peroxy).
Methods
To study the possibility of using Ti-peroxy as an antimicrobial prophylaxis, we developed a protocol for standardized susceptibility testing of bacteria.
Results
Importantly, we found that the resulting Ti-peroxy was highly antimicrobial against all aerobic species tested, among others, Staphylococcus aureus and Pseudomonas aeruginosa. Proteus mirabilis was slightly more resistant than, for example, Klebsiella pneumoniae and enterococci. In contrast, anaerobic bacteria Cutibacterium acnes and Parvimonas micra were equally susceptible compared to staphylococci.
Conclusions
Our findings suggest that the Ti-peroxy is a promising perioperative antimicrobial strategy that may be highly effective for prevention of post-operative infections. We therefore suggest application of hydrogen peroxide to implants prior to implantation.
Graphical abstract
These slides can be retrieved under Electronic supplementary material.
Extraforaminal entrapment of the L5 nerve root is uncommon, and its management can sometimes be very challenging.
Methods
We present the case of a 57-year-old female, complaining of a sciatica in her left leg, for 3 years, with no response to any kind of conservative treatment. MRI and CT scan revealed the presence of a large L5S1 strictly lateral osteophyte compressing the left L5 root in its extraforaminal path.
Results
The patient underwent a left anterior retroperitoneal approach with assistance from a vascular surgeon given the very close relation between the osteophyte and the left common iliac vein, lying just on top of it, osteophyte was removed in one piece with the use of an osteotome after retraction of the vessels. The patient progressively recovered from her left sciatic pain with a satisfactory clinical result at 1 year.
Conclusion
Literature is sparse on the treatment of extraforaminal entrapment of the L5 nerve root; the current case shows a successful treatment strategy with the use of an anterior approach for direct vision of the lesion and good control of the vessels.
To describe and discuss the diagnostic and treatment complexity of lymphatic system complications after scoliosis surgery.
Methods
Surgery for adolescent idiopathic scoliosis is very commonly performed with posterior pedicle screw instrumentation. Complications of the anteriorly based lymphatic system are, therefore, rare. We present a case with complications related to the lymphatic system, which have not been reported before after this type of surgery.
Results
After standard Th3 to Th12 posterior spinal reduction and fusion of a moderate thoracic curve, chyluria and a chylothorax developed in an adolescent girl. This appeared to be caused by an obstruction of the thoracic duct. Thorax drainage and finally thoracoscopic intervention prevented further pulmonal impairment. The exact cause could not be identified and the persistent lymph drainage problems had to be treated with a medium chain triglyceride diet.
Conclusion
With this report, we aim to create awareness of the lymphatic system in general and the possibility of severe complications, even after a posterior only approach of the vertebral column.
This observational study was aimed at quantification of low back pain (LBP) in Parkinsonian patients and its morphological correlation.
Background
Parkinson’s disease (PD) is a common disabling condition in the elderly population. Parkinsonian patients frequently are troubled by LBP. Causes for LBP in PD are muscular imbalances by the movement disorder itself and skeletal degeneration.
Methods
Ninety-seven PD patients and 97 controls were inquired about low back pain through the Oswestry Low Back Pain Disability Questionnaire and visual analogue scales. Fifty-four patients with LBP underwent X-ray of the lumbar spine in two planes and flexion–extension views. Parkinson’s disease was characterized by stage, disease duration, motor score, lateralization of symptoms and dosage of medication.
Results
LBP occurred significantly more frequent in PD (87.6%) compared to controls (62.6%) with longer duration and higher pain intensity. Pain intensity and disability scores were associated with higher PD stages and higher motor scores. Patients with the hypokinetic PD subtype experienced more pain intensity. X-ray of the lumbar spine revealed lumbar arthrosis in 79.6%, scoliosis in 38.8% and spondylolisthesis in 24.1% of PD patients with LBP. Lateralization of scoliosis and PD symptoms were significantly correlated. Only a small portion of PD patients with LBP received specialized orthopaedic treatment.
Conclusion
LBP and lumbar degeneration are common in PD. Both are related to movement disorder symptoms. The knowledge about musculoskeletal conditions in Parkinson’s disease is important for an interdisciplinary conservative or operative treatment decision of LBP.
Graphical abstract
These slides can be retrieved under Electronic Supplementary Material.
To assess the efficacy and safety of a new deformity correction philosophy treatment for AIS called apical vertebral derotation and translation (AVDT).
Methods
It is a retrospective study of prospectively collected data concerning two different scoliosis correction techniques used in our department. A total of 81 patients (22M, 59F) with a mean age of 15.5 years and minimum follow-up of 2 years were reviewed. Patients were divided into two groups according to the correction technique: 36 patients underwent single-rod derotation using all screws construct (AS), while 45 patients underwent apical vertebral derotation and translation using screws and sublaminar bands (SB).
Results
The mean improvement of the MT curve was 70% in the AS group and 60.6% in the SB group, while the mean improvement of the TL/L curve was 65.5 and 72.4%, respectively. PT increased in both groups after surgery with a mean amount of 2.5° in the AS group and only 1° in the SB group. We observed also a greater amount of cervical lordosis reduction in the AS group (4.5°) compared with the SB group (only 1°). The SB group had less operative time and less blood loss.
Conclusion
There was no significant difference between the two groups at the final follow-up and both techniques led to an excellent correction in the frontal plane; in the sagittal plane, the AVDT technique seemed to give less sagittal imbalance with better cervical profile; the surgical procedure is easy with less operative time, less blood loss and less risk of potential complications.
Graphical abstract
These slides can be retrieved under Electronic Supplementary Material.
We report a pancreatic fracture associated with Wirsung duct disruption, following a scoliosis surgery in a cerebral palsy adolescent.
Summary of background data
Spinal fusion surgery is the standard treatment for severe neuromuscular scoliosis. Many complications such as digestive ones account for its complexity. Postoperative acute pancreatitis is well described, although its pathophysiology remains unclear. To our knowledge, pancreatic fracture following scoliosis correction has never been described to date. Clinical presentation is not specific, and management is not consensual.
Case report
A 14-year-old adolescent had posterior spinal fusion for neuromuscular scoliosis due to cerebral palsy. During the postoperative course, she developed progressive nonspecific abdominal symptoms. The abdominal CT scan demonstrated a pancreatic fracture and a surgical exploration was decided as perforations of the bowel were highly suspected. Drains were placed around the pancreatic area as the retrogastric region was out of reach due to local inflammation. Conservative management led to the occurrence of a pseudocyst in the following weeks as the pancreatic leakage progressively dropped.
Discussion
Two hypotheses have been proposed: direct iatrogenic trauma from lumbar pedicle screws and pancreatic rupture related to the correction of the spinal deformity. As the latter seems the most likely, spinal surgeons should be aware of this occurrence following severe scoliosis correction.
Conclusion
Spinal fusion for severe neuromuscular scoliosis is a difficult procedure, with a high rate of complications. Among them, pancreatic fracture should be considered when abdominal pain persists in the postoperative period. Conservative management is advocated especially in case of a poor general condition.
Spinal fusion is used for treatment of spinal deformities, degeneration, infection, malignancy, and trauma. Reduction of motion enables osseous fusion and permanent stabilization of segments, compromised by loosening of the pedicle screws (PS). Deep implant infection, biomechanical, and chemical mechanisms are suspected reasons for loosening of PS. Study objective was to investigate the frequency and impact of deep implant infection on PS loosening.
Methods
Intraoperative infection screening from wound and explanted material sonication was performed during revision surgeries following dorsal stabilization. Case history events and factors, which might promote implant infections, were included in this retrospective survey.
Results
110 cases of spinal metal explantation were included. In 29.1% of revision cases, infection screening identified a germ, most commonly Staphylococcus (53.1%) and Propionibacterium (40.6%) genus. Patients screened positive had a significant higher number of previous spinal operations and radiologic loosening of screws. Patients revised for adjacent segment failure had a significantly lower rate of positive infection screening than patients revised for directly implant associated reasons. Removal of implants that revealed positive screening effected significant pain relief.
Conclusions
Chronic implant infection seems to play a role in PS loosening and ongoing pain, causing revision surgery after spinal fusion. Screw loosening and multiple prior spinal operations should be suspicious for implant infection after spinal fusion when it comes to revision surgery.
Graphical abstract
These slides can be retrieved under Electronic Supplementary Material.
The aim of this systematic review is to describe the epidemiology of chordoma and to provide a clear overview of clinical prognostic factors predicting progression-free and overall survival.
Methods
Four databases of medical literature were searched. Separate searches were performed for each of the two objectives. Reference and citation tracking was performed. Papers were processed by two independent reviewers according to a protocol that included risk of bias analysis. Disagreement was resolved by discussion. Pooled analyses were planned if homogeneity of data would allow.
Results
Incidence—incidence rates ranged between 0.18 and 0.84 per million persons per year and varied between countries and presumably between races. On average patients were diagnosed in their late fifties and gender data indicate clear male predominance. Two of the largest studies (n?=?400 and n?=?544) reported different anatomical distributions: one reporting the skull base and sacrococcygeal area affected in 32% and 29% of cases, whereas the other reporting that they were affected in 26% and 45% of cases, respectively.
Prognostic factors
Statistically significant adverse prognostic factors predicting progression-free and overall survival include female sex, older age, bigger tumour size, increasing extent of tumour invasion, non-total resection, presence of metastasis, local recurrence, and dedifferentiated histological subtype.
Conclusions
Incidence rate and anatomical distribution vary between countries and presumably between races. Most chordomas arise in the skull base and sacrococcygeal spine, and the tumour shows clear male predominance. Multiple adverse prognostic factors predicting progression-free and overall survival were identified in subgroups of patients.
Graphical abstract
These slides can be retrieved under Electronic Supplementary Material.
To investigate the effect of the preoperative cross-sectional area (CSA) of the semispinalis cervicis on postoperative loss of cervical lordosis (LCL) after laminoplasty.
Methods
A total of 144 patients who met the inclusion criteria between January 1999 and December 2015 were enrolled. Radiographic assessments were performed to evaluate the T1 slope, C2-7 sagittal vertical axis (SVA), cephalad vertebral level undergoing laminoplasty (CVLL), preoperative C2-7 Cobb angle, and preoperative CSA of the semispinalis cervicis.
Results
The T1 slope and the summation of the CSAs (SCSA) at each level of the semispinalis cervicis correlated with LCL, whereas the C2-7 SVA, CVLL, and preoperative C2-7 Cobb angle did not. Multiple regression analysis demonstrated that a high T1 slope and a low SCSA of the semispinalis cervicis were associated with LCL after laminoplasty in patients with cervical spondylotic myelopathy (CSM). The CSA of the semispinalis cervicis at the C6 level had the greatest association with LCL, which suddenly decreased with a LCL of 10°. The best cutoff point of the CSA of the semispinalis cervicis at the C6 level, which predicts LCL?>?10°, was 154.5 mm2 (sensitivity 74.3%; specificity 71.6%; area under the curve 0.828; 95% confidence interval 0.761–0.895).
Conclusion
Preoperative SCSA of the semispinalis cervicis was a risk factor for LCL after laminoplasty. Spine surgeons should evaluate semispinalis cervicis muscularity at the C6 level when planning laminoplasty for patients with CSM.
Graphical abstract
These slides can be retrieved under Electronic Supplementary Material.
The treatment of postoperative deep spinal wound infection involves debridement and intravenous antibiotics. Authors have previously reported success in a small series of patients treated with vacuum-assisted closure (VAC) therapy, but its use over exposed dura is controversial and the outcome has not been reported in large series.
Purpose
To review the outcomes following the treatment of postoperative spinal infections with VAC therapy, particularly those with exposed dura.
Methods
This is a review of prospectively collected data in 42 patients, all of whom had deep postoperative spinal infections. 30 of these patients had exposed dura. All patients had an initial debridement followed by application of VAC Whitefoam (with exposed dura) or grey Granufoam (where no dura was exposed). Pressure was set at 50 mmHg with exposed dura or 125 mmHg where no dura was exposed. All patients underwent a minimum 6 week course of antibiotics. We report on the number of visits to theatre required for dressing changes and debridement and the eventual outcomes.
Results
Five patients required a flap reconstruction. Two patients died before definitive final closure due to other complications (pneumonia and stroke). In all the other patients, their wounds healed fully. A mean of 2.3 infection surgeries were required to eradicate infection and achieve wound closure.
Conclusions
This is one of the largest studies which confirms the safety and efficacy of VAC dressings in patients with spinal wound infections, even when the dura is exposed.
Graphical abstract
These slides can be retrieved under Electronic Supplementary Material.
The preoperative prediction of medical complications is essential to optimize perioperative management. SpineSage? is a free of charge online calculator to predict medical complications in spine surgery. The current study utilizes it in patients undergoing spine surgery to assess whether the predicted risks would correlate with the actual complication rate in clinical practice.
Methods
A total of 273 consecutive patients who underwent spinal surgery were assessed. The risk of medical complications was predicted for each patient, and all medical complications were recorded within 30 days of surgery. Based on their predicted risk of complication, patients were divided into three risk groups (<?15, 15–30, >?30%).
Results
The predicted overall risk of medical complications was 14.7% and was comparable to the observed complication rate of 16.1%. The predicted risk for major medical complications (3.8%) was also similar to the observed complication rate (3.3%). Detailed analysis of the segmented risk groups suggests a close correlation between predicted and actual complication rates. Receiver operating characteristic analysis revealed an area under the curve of 0.71 (p?<?0.001) for the prediction of overall medical complications and 0.85 (p?<?0.001) for major complications.
Conclusions
The online risk calculator predicted both overall and major medical complications. The tool can assist in preoperative planning and counseling of patients.
Graphical abstract
These slides can be retrieved under Electronic Supplementary Material.
Despite proven biomechanical superiority and resultant superior clinical outcomes, pedicle instrumentation in cervical spine is not widely practiced due to technical difficulties, steep learning curve, and possible potential catastrophic complications due to screw misplacement. This study was undertaken with the purpose to evaluate the feasibility, accuracy, and complications of cervical pedicle screw instrumentation solely using O-arm-based 3D navigation technology.
Methods
Prospectively maintained data from a single-surgeon case series were retrospectively analyzed. All the patients had undergone cervical pedicle instrumentation under O-arm 3D navigation. Screw placement accuracy was analyzed and compared among different vertebral levels and also between different patient groups.
Results
A total of 241 cervical pedicle screws were inserted in 44 patients. Out of the 241 screws, 197 (81.74%) were inserted at the level of C3–C6 vertebrae with nearly equal distribution among the 4 vertebrae, followed by 32 (13.28%) and 12 (4.98%) screws at C2 and C7 vertebrae, respectively. After the analysis of screw placement as per Gertzbein classification, the overall breach rates were found to be 7.05% (17 screws) with 52.94% (10 screws) Grade I, 47.06% (7 screws) Grade II, and nil Grade III screw breaches.
Conclusion
The use of O-arm-based intra-operative 3D scans for navigation can make cervical pedicle screw placement reliable. High accuracy and better intra-operative control can increase surgeon’s confidence in using cervical pedicle instrumentation on more regular basis.
Graphical abstract
These slides can be retrieved under Electronic Supplementary Material.
The global appearance of scoliosis in the horizontal plane is not really known. Therefore, the aims of this study were to analyze scoliosis in the horizontal plane using vertebral vectors in two patients classified with the same Lenke group, and to highlight the importance of the information obtained from these vertebral vector-based top-view images in clinical practice.
Methods
Two identical cases of scoliosis were selected, based on preoperative full-body standing anteroposterior and lateral radiographs obtained by the EOS? 2D/3D system. Three-dimensional (3D) surface reconstructions of the spinal curves were performed by using sterEOS? 3D software before and after surgery. In both patients, we also determined the vertebral vectors and horizontal plane coordinates for analyzing the curves mathematically before and after surgery.
Results
Despite the identical appearance of spinal curves in the frontal and sagittal planes, the horizontal views seemed to be significantly different. The vertebral vectors in the horizontal plane provided different types of parameters regarding scoliosis and the impact of surgical treatment: reducing lateral deviations, achieving harmony of the curves in the sagittal plane, and reducing rotations in the horizontal plane.
Conclusions
Vertebral vectors allow the evolution of scoliosis curve projections in the horizontal plane before and after surgical treatment, along with representation of the entire spine. The top view in the horizontal plane is essential to completely evaluate the scoliosis curves, because, despite the similar representations in the frontal and sagittal planes, the occurrence of scoliosis in the horizontal plane can be completely different.
Graphical abstract
These slides can be retrieved under Electronic Supplementary Material.
Bone substitutes’ advantage is enhancing arthrodesis biologic support without further autologous bone graft harvested from other skeleton sites, as from posterior iliac crests; however, in our experience, bone substitutes’ integration is often incomplete.
Methods
From 2012 to 2017, we operated 108 patients by posterior instrumented vertebral arthrodesis in adolescent idiopathic scoliosis (AIS) correction, mean main curve 80° Cobb, and mean age 12 years and 6 months, with all pedicle screws instrumentation in main curve/curves area and hooks at upper tip of implant; bone graft has been harvested only at vertebral level, without bone substitutes or autologous graft from other patient sites or allogenic bone graft. We matched this group with 98 patients previously operated in which we used calcium triphosphate.
Results
At 3 year mean follow-up, all patients in group treated with autologous bone graft only have complete and stable arthrodesis without loss of correction (mean curve 27° Cobb) or instrumentation failure. At 6 year mean follow-up in the group treated with autologous bone graft augmented by calcium triphosphate, 96 patients have stable arthrodesis without loss of correction (mean curve 24°), 1 case has implant break, and 1 case has 8° Cobb loss of correction.
Conclusion
Bone substitutes are a further cost in arthrodesis surgery and suboptimal integration leaves foreign bodies on vertebras. Our experience shows that all pedicle screw instrumentation and bracing after surgery obtain stable correction showing in time a solid arthrodesis with autologous bone only, harvested at local site, without bone substitutes or further bone graft.
