Postoperative spine infections

Postoperative spinal wound infection is a potentially devastating complication after operative spinal procedures. Despite the uti- lization of perioperative prophylactic antibi- otics in recent years and improvements in sur- gical technique and postoperative care, wound infection continues to compromise patients’ outcome after spinal surgery. In the modern era of pending health care reform with increasing financial constraints, the financial burden of post-operative spinal infections also deserves consideration. The aim of our work is to give to the reader an updated review of the latest achievements in prevention, risk factors, diagnosis, microbiology and treatment of post- operative spinal wound infections. A review of the scientific literature was carried out using electronic medical databases Pubmed, Google Scholar, Web of Science and Scopus for the years 1973-2012 to obtain access to all publica- tions involving the incidence, risk factors, pre- vention, diagnosis, treatment of postoperative spinal wound infections. We initially identified 119 studies; of these 60 were selected. Despite all the measures intended to reduce the inci- dence of surgical site infections in spine sur- gery, these remain a common and potentially dangerous complication

Spinal surgery complications: an unsolved problem—Is the World Health Organization Safety Surgical Checklist an useful tool to reduce them?

Abstract Purpose To investigate whether the World Health Organization Safety Surgical Checklist (SSC) is an effective tool to reduce complications in spinal surgery. Methods We retrospectively evaluated the clinical and radiological charts prospectively collected from patients who underwent a spinal surgery procedure from January 2010 to December 2012. The aim of this study was to compare the incidence of complications between two periods, from January to December 2010 (without checklist) and from January 2011 and December 2012 (with checklist), in order to assess the checklist's effectiveness. Results The sample size was 917 patients with an average of 30-month follow-up. The mean age was 52.88 years. The majority of procedures were performed for oncological diseases (54.4%) and degenerative diseases (39.8%). In total, 159 complications were detected (17.3%). The overall incidence of complications for trauma, infectious pathology, oncology, and degenerative disease was 22.2%, 19.2%, 18.4%, and 15.3%, respectively. No correlation was observed between the type of pathology and the complication incidence. We observed a reduction in the overall incidence of complications following the introduction of the SSC: In 2010 without checklist, the incidence of complications was 24.2%, while in 2011 and 2012, following the checklist introduction, the incidence of complications was 16.7% and 11.7%, respectively (mean 14.2%). Conclusions The SSC seems to be an effective tool to reduce complications in spinal surgery. We propose to extend the use of checklist system also to the preoperative and postoperative phases in order to further reduce the incidence of complications. Graphic abstract These slides can be retrieved under Electronic Supplementary Material

Carbon Fiber-Reinforced PolyEtherEtherKetone (CFR-PEEK) Instrumentation in Degenerative Disease of Lumbar Spine: A Pilot Study

: CFR-PEEK is gaining popularity in spinal oncological applications due to its reduction of imaging artifacts and radiation scattering compared with titanium, which allows for better oncological follow-up and efficacy of radiotherapy. We evaluated the use of these materials for the treatment of lumbar degenerative diseases (DDs) and considered the biomechanical potential of the carbon fiber in relation to its modulus of elasticity being similar to that of bone. Twenty-eight patients with DDs were treated using CRF-PEEK instrumentation. The clinical and radiographic outcomes were collected at a 12-month FU. Spinal fusion was evaluated in the CT scans using Brantigan scores, while the clinical outcomes were evaluated using VAS, SF-12, and EQ-5D scores. Out of the patients evaluated at the 12-month FU, 89% showed complete or almost certain fusion (Brantigan score D and E) and presented a significant improvement in all clinical parameters; the patients also presented VAS scores ranging from 6.81 ± 2.01 to 0.85 ± 1.32, EQ-5D scores ranging from 53.4 ± 19.3 to 85.0 ± 13.7, SF-12 physical component scores (PCSs) ranging from 29.35 ± 7.04 to 51.36 ± 9.75, and SF-12 mental component scores (MCSs) ranging from 39.89 ± 11.70 to 53.24 ± 9.24. No mechanical complications related to the implant were detected, and the patients reported a better tolerance of the instrumentation compared with titanium. No other series of patients affected by DD that was stabilized using carbon fiber implants have been reported in the literature. The results of this pilot study indicate the efficacy and safety of these implants and support their use also for spinal degenerative diseases

La terapia con ioni carbonio nel trattamento del cordoma del sacro

La presente tesi rappresenta il frutto di uno studio prospettico svolto in collaborazione tra il Centro Nazionale per l’Adroterapia Oncologica di Pavia e la Struttura Complessa di Chirurgia Vertebrale ad Indirizzo Oncologico e Degenerativo dell’Istituto Ortopedico Rizzoli di Bologna. Scopo del lavoro è quello di dimostrare l’efficacia della terapia con ioni carbonio nel trattamento dei cordomi del sacro. Il cordoma è un tumore maligno di natura mesenchimale che mostra differenziazione notocordale. Si tratta del tumore maligno primitivo della colonna più frequente. La localizzazione più comune è rappresentata sacro in cui si localizza circa il 50% dei cordomi. Attualmente l’asportazione en bloc con margini ampi della massa tumorale resta l’opzione di trattamento di maggior successo. Il curretage intralesionale, al contrario, si è dimostrato inefficace nel controllo locale della patologia. Tuttavia nella patologia tumorale della colonna e del sacro non sempre è possibile asportare in blocco con margini ampi la lesione tumorale senza causare danni invalidanti per il paziente. I cordomi del sacro in particolare rappresentano sfide chirurgiche uniche sia per la localizzazione sia per le grandi dimensioni con cui si presentano al momento della diagnosi. I rischi chirurgici potenziali sono molteplici e rappresentati principalmente dalle perdite ematiche massive, dal rischio elevato di lesione di strutture nervose e dall’elevato rischio di infezione delle ferite chirugiche. Come tutti i tumori mesenchimali anche il cordoma è considerato, classicamente, scarsamente sensibile alla radioterapia convenzionale con fotoni. Nei decenni passati, al fine di aumentare la dose terapeutica efficace a livello del tessuto tumorale bersaglio, sono state sviluppate nuove tecniche radioterapiche. In particolare l’utilizzo degli adroni, come protoni o le particelle ad alta energia come gli ioni cabonio, elio o neon, ha permesso di aumentare il dosaggio delle radiazioni a livello del sito bersaglio con una minore tossicità ai tessuti circostanti ed una efficacia radiobiologica superiore. La terapia con particelle possiede caratteristiche vantaggiose sia dal punto di vista fisico che biologico rispetto alla terapia con fotoni. Tra il gennaio 2013 ed il dicembre 2016, 18 pazienti con diagnosi di cordoma dimostrata istologicamente sono stati trattati con radioterapia a ioni carbonio. Tutti i pazienti sono stati sottoposti ad una valutazione volumetrica del bersaglio tramite acquisizione di immagini di risonanza magnetica (RM) e tomografia computerizzata (TC) previa immobilizzazione rigida. La dose totale è stata di 70.4 GyE in frazioni giornaliere da 4.4GyE per un totale di 16 frazioni in 4 settimane. Alcuni pazienti sono stati sottoposti ad intervento chirurgico di distanziamento dell’intestino dalla massa neoplastica e posizionamento di uno spaziatore al fine di evitare una tossicità intestinale. Tutti i pazienti sono stati seguiti per valutazione dell’efficacia e dell’eventuale tossicità radioterapica ogni 3 mesi dopo la radioterapia tramite valutazione clinica e risonanza magnetica presso il CNAO. PET – CT e la biopsia sono state eseguite dopo 6-12 mesi dal trattamento presso l’ospedale Sant’Orsola e l’Istituto Ortopedico Rizzoli di Bologna rispettivamente. In tutti i Pazienti ad eccezione di uno la terapia con ioni carbonio si è dimostrata efficace nel trattamento dei cordomi del sacro. L’efficacia è stata dimostrata radiologicamente ed istologicamente. Inoltre la radioterapia si è mostrata efficace nella gestione del dolore

LE RICOSTRUZIONI 3D TC GUIDATE NEL PLANNING OPERATORIO DELLA CHIRURGIA DELL'ANCA

La tesi analizza il planning operatorio nella chirurgia dell'anca come metodo per migliorare la qualità degli interventi chirurgici sull' anca. Questo tipo di approccio ha l'intento di ottimizzare la chirurgia dell'anca cercando di diminuire costi,tempi,e complicanze che tale chirurgia può implicare. Nei 4 casi presi in considerazione viene utilizzato per la ricostruzione delle immagini TC il software open source ITK SNAP 1.5.0 della cognita corporation, cui è stato integrato il tool box ideato da ENDOCAS che permette di selezionare all'interno della ricostruzione tridimensionale le porzioni anatomiche di rilievo dal punto di vista chirurgico. In due casi è stato costruito un modello in plastica Abs plus su cui è stato possibile svolgere una simulazione di intervento. In tutti i casi è stata ottenuta una buona biomeccanica articolare. In nessun caso si sono verificate complicanze neurologiche o vascolari. In conclusione abbiamo analizzato il rapporto costi-benefici dell' impiego di questo tipo di planning

PATIENT-SPECIFIC TEMPLATES FOR PLACEMENT OF PEDICLE SPINE SCREWS: PROPOSAL OF A NEW DESIGN

Pedicle screws fixation to stabilize lumbar spinal fusion has become the gold standard for posterior stabilization. However their positioning remain difficult due to variation in anatomical shape, dimensions and orientation, which can determine the inefficacy of treatment or severe damages to close neurologic structures. Image guided navigation allows to drastically decrease errors in screw placement but it is used only by few surgeons due to its cost and troubles related to its using, like the need of a localizer in the surgical scenario and the need of a registration procedure. An alternative image guided approach, less expensive and less complex, is the using of patient specific templates similar to the ones used for dental implants or knee prosthesis. Like proposed by other authors we decided to design the templates using CT scans. (slice thickness of 2.0 mm). Template developing is done, for each vertebra, using a modified version of ITK-SNAP 1.5 segmentation software, which allow to insert cylinders (full or empty) in the segmented images. At first we segment the spine bone and then the surgeon chose screw axes using the same software. We design each template with two hollow cylinders aligned with the axes, to guide the insertion in the pedicle, adding contact points that fit on the vertebra, to obtain a template right positioning. Finally we realize the templates in ABS using rapid prototyping. After same in-vitro tests, using a synthetic spine (by Sawbones), we studied a solution to guarantee template stability with simple positioning and minimizing intervention invasiveness. Preliminary ex-vivo animal testing on porcine specimens has been conducted to evaluate template performance in presence of soft-tissue in place, simulating dissection and vertebra exposure. For verification, the surgeon examined post-operative CT-scans to evaluate Kirschner wires positioning. During the ex-vivo animal test sessions, template alignment resulted easy thanks to the spinous process contact point. Their insertion required no additional tissue removal respect to the traditional approach. The positioning of contact points on vertebra's lamina and articular processes required just to shift the soft tissue under the cylinders bases. The surgeon in some cases evaluated false stable template positions since not each of the 4 contact points were actually in contact with the bone surface and tried the right position. CT evaluation demonstrate a positive results in 96.5% of the Kirschner wires implanted. Our approach allows to obtain patient specific templates that does not require the complete removal of soft tissue around vertebra. Guide positioning is facilitated thanks to the using of the spinous processes contact point, while false stable positions can be avoided using four redundant contact points. The templates can be used to guide the drill, the insertion of Kirschner in case of use of cannulated screws or to guide directly the screw. After these preliminary ex-vivo animal tests we obtained the authorization of the Italian Health Ministry to start the human study

Treatment of Scaphoid Waist Nonunion Using Olecranon Bone Graft and Stryker Asnis Micro Cannulated Screw: A Retrospective Study-80 Case Studies and 6 Years of Follow-Up

Background Screw fixation and bone grafting are the gold standard for scaphoid waist nonunion without avascular necrosis. Question/Purpose Assesses the scaphoid waist nonunion healing rate with use of an uncommon cancellous bone graft (olecranon) and an unusual fixation system (Asnis Micro Cannulated Screw System; Stryker Inc., Kalamazoo, MI, USA). Material and Methods A series of 102 consecutive patients were treated for scaphoid waist nonunion (without deformity). Of these, 80 patients subjected to clinical (Modified Mayo Wrist Score (MMWS), Jamar hydraulic dynamometer) and radiographic examination before and after surgery were evaluated. Ipsilateral olecranon cancellous bone graft and the ASNIS Micro 3.0-mm diameter screw, were used. The average follow up was 6 years (min 3; max 10). Results Radiographic consolidation was achieved in 90% of patients; dorsal intercalated segment instability (DISI) deformities were corrected in 71.4% of cases. Ninety percent improved the range of motion of the wrist and grip strength. All patients showed a significant reduction of peak force in the operated hand. In 6.25% we observed clinical and radiographic screw head-trapezium impingement. Twenty-six patients developed a degenerative wrist sign. The MMWS yielded 68 optimal, 8 good, and 4 bad results. Conclusions To treat scaphoid waist nonunions without misalignment, low-profile headed screw and olecranon bone graft allowed a high consolidation rate with positive results to long-term follow-up. The Asnis Micro 3.0 mm diameter screw may be a suitable option for treating scaphoid waist nonunion. Level of Evidence IV

Computer Tomography Prototyping and Virtual Procedure Simulation in Difficult Cases of Hip Replacement Surgery.

Each year approximately 1 million total hip replacements (THR) are performed worldwide. A percentage of failure due to surgical approach and imprecise implant placement still exists. These result in several serious complications. We propose an approach to plan, to simulate, and to assist prosthesis implantation for difficult cases of THR based on 3-D virtual models, generated by segmenting patients' CT images, 3-D solid models, obtained by rapid prototyping (RP), and virtual procedure simulation. We carried out 8 THR with the aid of 3-D reconstruction and RP. After each procedure a questionnaire was submitted to the surgeon to assess the perceived added value of the technology. In all cases, the surgeon evaluated the 3-D model as useful in order to perform the planning. The clinical results showed a mean increase in the Harris Hip Score of about 42.5 points. The mean time of prototyping was 7.3 hours, (min 3.5 hours, max 9.3 hours). The mean surgery time was 65 minutes (min 50 minutes, max 88 minutes). Our study suggests that meticulous preoperative planning is necessary in front of a great aberration of the joint and in absence of normal anatomical landmarks, CT scan is mandatory, and 3-D reconstruction with solid model is useful

Patient’s Specific Template for Spine Surgery

Currently, Pedicle screws are positioned using a freehand technique or under fluoroscopic guidance. Although computer navigation has improved its accu- racy over the last years, image guided navigation has still little use among physi- cians for orthopaedic surgeries. This is because computer assisted surgeries are very expensive, specially the required equipment, and also has difficulties related to use. The drill must be perfectly orientated following the navigator screen, which is no easy task to perform. A new asset for pedicle screw placement is to use a robotic platform, which reduces misplacement. However, it is too expensive and its learning curve can take a long time to be completed. In some cases this kind of technology must not be useful and practical. A third solution for pedicle screw placement is to use Patient’s Specific Templates, which is less expensive and less complex to learn. This alternative is stable at a unique position, easy to use, easy to place (with high reproducibility), less invasive and more accurate. The time from design to produc- tion of one template is short, although it depends by the familiarization with the software used (time spent for the preoperative planning and the template design) and by the 3D printer used. Previously planned surgeries reduce costs and the time spent in the operating room during a procedure because surgeons can predict and perform the surgery before the real operation. Furthermore the use of patient’s spe- cific templates can save surgeons from potential errors, and consequently additional costs for the health system due to additional treatments or legal reasons

Biomechanics of Interspinous Devices

A number of interspinous devices (ISD) have been introduced in the lumbar spine implant market. Unfortunately, the use of these devices often is not associated with real comprehension of their biomechanical role. The aim of this paper is to review the biomechanical studies about interspinous devices available in the literature to allow the reader a better comprehension of the effects of these devices on the treated segment and on the adjacent segments of the spine. For this reason, our analysis will be limited to the interspinous devices that have biomechanical studies published in the literature