Andrea Zanirato

Kümmell disease: illustrative case for definition criteria

Kümmell disease (KD) is defined as a clinical condition in which patients develop a painful progressive angular kyphosis as a result of a delayed vertebral body collapse after a minor spinal trauma [1–3]. The most supported etiopathogenetic hypothesis is a posttraumatic avascular necrosis of the vertebral body [4]. The main cornerstones of KD are history of trauma with a negative x-ray investigation, an asymptomatic period, and a recurrence of symptoms that results in painful kyphosis deformity of the affected spine [5]. Intravertebral vacuum cleft is a widely reported radiological sign associated with KD [6,7]. Literature on this subject is limited and characterized by some inaccuracies and wrong diagnosis. Kümmell disease needs to be distinguished from other clinical situations, such as osteoporosis vertebral fractures or idiopathic

Which patients risk segmental kyphosis after short segment thoracolumbar fracture fixation with intermediate screws

INTRODUCTION The use of intermediate screws in fractured vertebrae has been proposed to decrease the number of fused levels in thoracolumbar fractures and to enable short fixations. The aim of this study was to evaluate the results of this technique and to establish predictive factors involved in loss of segmental kyphosis correction (LKC). METHODS Forty-three patients who underwent short-segment spinal fixation with intermediate screws for a thoracolumbar spine fracture in a two-year time period were enrolled in the study. Patients had AO-type A3, A4 and B2 thoracolumbar fractures. Radiological parameters included segmental kyphosis (SK), vertebral wedge angle (VWA) and loss of anterior and posterior vertebral body height. Patients were evaluated up to one-year follow-up. The correlation between LKC and potential risk factors, such as smoking habit, sex, age, neurological status and BMI was evaluated. RESULTS Mean preoperative SK was 16.5°±6.5°, and it decreased to 3.4°±3.5° postoperatively (P<0.01). At the one-year follow-up mean SK dropped to 5.5°±3.9° (P<0.01). Mean preoperative VWA was 20.0°±8.1°, and significantly improved to 6.3°±3.1° after surgery (P<0.01). There was a mean LKC of 1.8°±2.1°at one year. LKC mildly correlated with body mass index (BMI, r: +0.31), and obese patients (BMI>30) had an increased risk of LKC at the one-year follow-up (P=0.03; odds ratio [OR]=3.2). DISCUSSION Analysis of the radiological data at one-year follow-up showed that all the evaluated parameters were associated with a mild loss of correction, with no impact on the clinical outcomes or implant failure. These findings confirm the trends reported in the literature. The correlation between LKC and clinical features, such as BMI, age, sex, smoking habit and preoperative neurological status was investigated. Interestingly, a positive correlation was observed between BMI and LKC, and obese patients with BMI>30 had an increased risk of LKC at one-year follow-up (OR 3.2); to our knowledge this finding has never before been reported. CONCLUSION Short-segment fixation with intermediate screws is a viable technique with positive clinical and radiological outcomes at one-year follow-up. However, surgeons should be aware that in obese patients (BMI>30) this technique is associated with an increased risk of LKC. LEVEL OF EVIDENCE 3.

Is it possible to preserve lumbar lordosis after hybrid stabilization? Preliminary results of a novel rigid-dynamic stabilization system in degenerative lumbar pathologies

AbstractPurpose of the studyTo evaluate the results of a novel rigid–dynamic stabilization technique in lumbar degenerative segment diseases (DSD), expressly pointing out the preservation of postoperative lumbar lordosis (LL).Materials and methods Forty-one patients with one level lumbar DSD and initial disc degeneration at the adjacent level were treated. Circumferential lumbar arthrodesis and posterior hybrid instrumentation were performed to preserve an initial disc degeneration above the segment that has to be fused. Clinical and spino-pelvic parameters were evaluated pre- and postoperatively.ResultsAt 2-year follow-up, a significant improvement of clinical outcomes was reported. No statistically significant difference was noted between postoperative and 2-year follow-up in LL and in disc/vertebral body height ratio at the upper adjacent fusion level.ConclusionsWhen properly selected, this technique leads to good results. A proper LL should be achieved after any hybrid stabilization to preserve the segment above the fusion.

What is the clinical evidence on regenerative medicine in intervertebral disc degeneration

PurposeThis review aims to explore and summarize the current clinical evidence about the use of regenerative medicine such as mesenchymal stem cells or platelet-rich plasma in intervertebral disc regeneration, in order to clarify the state of art of these novel approaches.Materials and methodsWe performed a research of the available literature about regenerative medicine strategies aiming to prevent intervertebral disc degeneration. All preclinical trials and in vitro studies were excluded. Only clinical trials were critically analysed.ResultsThe manuscript selection produced a total of 7 articles concerning the use of regenerative therapies in intervertebral disc degeneration, covering the period between 2010 and 2016. Articles selected were 4 about the injection of mesenchymal stem cells-related results and 3 using platelet-rich plasma. The total population of patients treated with regenerative medicine strategies were 104 patients.ConclusionsRegenerative medicine, such as the use of mesenchymal stem cells or platelet-rich plasma, in intradiscal disc degeneration has shown preclinical and clinical positive results. Randomized clinical trials studying the potential of MSCs intradiscal injection have not been conducted, and PRP effect has been studied only preliminarily. Additional more powered high-quality studies are needed to really appreciate the long-term safety and efficacy of regenerative medicine approaches in IDD.

Vertebral body osteonecrosis: proposal of a treatment-oriented classification system

AbstractPurposeTo present a classification system for vertebral body osteonecrosis (VBON) based on imaging findings and sagittal alignment and consequently to propose treatment guidelines.MethodsChart 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.ResultsThe 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.ConclusionsThe 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.

What is the Current Evidence on Vertebral Body Osteonecrosis?: A Systematic Review of the Literature

Osteonecrosis (ON) is a clinical entity characterized by a pattern of cell death and complex process of bone resorption and formation. Studies related to ON have largely focused on certain anatomical sites; however, the evidence on vertebral body ON (VBON) is largely inconsistent and fragmented. The aim of this study was to clarify the pathophysiology, risk factors, imaging findings, and available treatment modalities for VBON. A systematic review of the relevant articles published in English was performed using PubMed, Embase, Medline, Google Scholar, Cochrane Central Register of Controlled Trials (CENTRAL), and CINAHL databases. A total of 81 articles were included in this study. Three main topics about VBON were identified: (1) pathophysiology and risk factors, (2) diagnosis, and (3) treatment. Forty-five studies were based on the pathophysiology, 52 on diagnosis, and 38 on the treatment options for VBON. The literature on VBON was limited and mainly focused on post-traumatic cases with a considerable overlap with nonunion and pseudoarthrosis.

Porous metal cones: gold standard for massive bone loss in complex revision knee arthroplasty? A systematic review of current literature

IntroductionRevision knee arthroplasty is increasing, and in that case, bone loss management is still a challenging problem. In the last years, the body of literature and interest surrounding porous metal cones has grown, but few systematic evaluations of the existing evidence have been performed. The aim of our systematic review is to collect and critically analyze the available evidence about metal cones in revision knee arthroplasty especially focusing our attention on indications, results, complications, and infection rate of these promising orthopaedic devices.Materials and methodsWe performed a systematic review of the available English literature, considering the outcomes and the complications of tantalum cones. The combinations of keyword were “porous metal cones”, “knee revision”, “bone loss”, “knee arthroplasty”, “periprosthetic joint infection”, and “outcome”.ResultsFrom the starting 312 papers available, 20 manuscripts were finally included. Only one included study has a control group. The main indication for metal cones is type IIb and III defects according AORI classification. Most of the papers show good clinical and radiological outcomes with low rate of complications.ConclusionThe examined studies provide encouraging clinical and radiological short-to-mid-term outcomes. Clinical studies have shown a low rate of aseptic loosening, intraoperative fractures, infection rate and a lower failure rate than the previous treatment methods. Higher quality papers are needed to draw definitive conclusions about porous metal cones.

Lumbar total disc arthroplasty: outdated surgery or here to stay procedure? A systematic review of current literature

BackgroundThe purpose of this study was to summarize the available evidence about total lumbar disc replacement (TDR), focusing our attention on four main topics: clinical and functional outcomes, comparison with fusion surgery results, rate of complications and influence on sagittal balance.Materials and methodsWe systematically searched Pubmed, Embase, Medline, Medscape, Google Scholar and Cochrane library databases in order to answer our four main research questions. Effective data were extracted after the assessment of methodological quality of the trials.ResultsFifty-nine pertinent papers were included. Clinical and functional scores show statistically significant improvements, and they last at all time points compared to baseline. The majority of the articles show there is no significant difference between TDR groups and fusion groups. The literature shows similar rates of complications between the two surgical procedures.ConclusionsTDR showed significant safety and efficacy, comparable to lumbar fusion. The major advantages of a lumbar TDR over fusion include maintenance of segmental motion and the restoration of the disc height, allowing patients to find their own spinal balance. Disc arthroplasty could be a reliable option in the treatment of degenerative disc disease in years to come.Level of evidenceII.

Reply to “Letter to the Editor: adjacent segment infection complicates long segment fusion in elderly patients”

We kindly thank the Editor for giving us the opportunity to discuss such an interesting topic as adjacent segment infection (ASI). Adjacent segment infection (ASI) is undoubtedly a rare and feared complication in spinal surgery. Few cases have been reported in the literature [1–3]. Pedicle subtraction osteotomy (PSO) leads to optimal clinical and radiological results and provides correction of rigid spinal deformities with major sagittal imbalance [4,5]. On the other hand, this procedure is technically demanding and is affected by high complication rates mainly due to mechanical or biological failure, especially in elderly patients [6,7]. Despite such different complications, no mention of ASI after PSO is present in the literature. Our aim was to point out that ASI should be considered after a PSO, especially in patients with correlated symptoms such as fever, sudden neurologic impairment, and suggestive hematological data. To the best of our knowledge, only one published data about ASI in sterile spine surgery is present in the literature. Of the three papers [1–3] ever published about ASI, two of them argued of cases that occurred after spondylodiscitis. In the work of Siam et al. the authors stated that of the 11 patients with positive microbiological findings, 8 of them were colonized by the same microorganism previously detected in the first surgery. This evidence poses several questions about the correct management of the primary site of infection and suggest that the ASI is strictly linked to the first episode of spondylodiscitis. In the Letter to the Editor, the authors affirmed that the risk of developing ASI after fusion was 10 times higher in long instrumentations in respect of short ones. This conclusion could be affected by several biases such as operative time or different surgical techniques. Moreover, as the authors stated in the text, general health status is a key point in the genesis of this disease. In the work of Siam et al. [3], of the 23 ASI, 19 were after posterior lumbar interbody fusion (PLIF) (mean 2.8 level/patient), 3 were thoracolumbar fractures, and 1 was a cervical one (4-level fusion). These are generally considered short fusion procedures. In conclusion, our paper aims [8] to highlight an unreported complication after PSO to increase surgeons’ knowledge about complications after PSO and long-fusion procedures. We hope that our report could be considered in a wider literature-based database of ASI that prepares the ground for general guidelines to better manage this rare but devastating complication.

Lumbar lordosis preservation after hybrid stabilization: prelimary results of a novel rigid-dynamic stabilization system in degenerative lumbar pathologies

Italian Spine Society National Congress