Vertebral balloon kyphoplasty versus vertebral body stenting in non-osteoporotic vertebral compression fractures at the thoracolumbar junction: a comparative radiological study and finite element analysis (BONEXP study).

OBJECTIVE: To compare radiologically balloon kyphoplasty (BKP) and vertebral compression fracture (VCF) expansion and corroborate with a finite element (FE) analysis. The principle of BKP is to stabilize VCF by restoring vertebral body anatomy using bone expansion and cement filling. More recently, vertebral body stenting (VBS) has been developed to reduce the loss of vertebral height observed after balloon deflation. METHODS: A retrospective, monocentric and continuous study of 60 non-osteoporotic fractures of the thoracolumbar junction treated by vertebral bone expansion was carried out over three years. The main endpoint was radiological correction of vertebral kyphosis (VK) at 3 months. The other studied parameters were vertebral height, index of Farcy, index of Beck, cement leakages and their location. A FE model was developed to analyze effects linked to the stent during cement injection, specifically throughout the risk of cement leakage evaluation. RESULTS: After three months, average reduction of VK was 4.73° ± 4.8° after BKP, and 4.63° ± 2.7° after VBS. There was no difference between the two techniques, but cement leakage was significantly greater with BKP (41.7%) than with VBS (4.2%). FE analysis showed substantial changes of the cement flow orientation in the presence of a stent. CONCLUSION: BKP and VBS offer comparable expansion with no added value of VBS in non-osteoporotic VCF reduction. VBS technique appears to prevent cement leakage due to its mesh architecture hindering the leaking process. In counterpart, such balloon expansion is likely to require higher pressure to deploy the stent. This could be an important parameter to take into account in young patients with high bone density.

First description of bacteremia caused by Oscillibacter valericigenes in a patient hospitalized for leg amputation.

Initially isolated from the alimentary canal of a Japanese corbicula clam, Oscillibacter valericigenes is a Gram-negative rod, of which culture remains very difficult. Herein we present the first case of bacteremia due to Oscillibacter valericigenes, in humans. A 55-year-old man was hospitalized for clinical management of multiple neglected leg wounds (colonized with maggots) that had occurred during a motorcycle accident. Following radiological confirmation of the bone infection, a transfemoral amputation was performed to limit the risk of extended infection. During hospitalization, before the amputation, the patient experienced fever, biological inflammation justifying the sampling of multiple blood cultures. Anaerobic blood culture was positive after 34 hours, without identification by routine procedure (MALDI-TOF), justifying identification by 16S DNA sequencing. In the absence of possible subculture, antibiotic sensitivity testing could not be performed. A pre-emptive treatment by piperacillin-tazobactam was introduced for 14 days. The evolution was good, except for a local disunion. Complete phylogenic analysis of the clinical strain showed that it significantly differed from the reference strain, which is distantly related to the Clostridia cluster IV. Due to the culture conditions and specialized identification method by sequencing, prevalence of O. valericigenes may be underestimated. Optimization of blood culture procedures and utilization of 16S rRNA gene sequencing are tools needed for identification of rare pathogens that could help to optimize clinical management of infected patients.

Isolated Acute Traumatic Subtalar Dislocations: Review of 13 Cases at a Mean Follow-Up of 6 Years and Literature Review.

Isolated acute traumatic subtalar dislocations are quite rare. They correspond to talotarsal dislocation, including the talonavicular and talocalcaneal joints. The purpose of the present study was to evaluate the functional and radiologic outcomes of the treatment of acute traumatic isolated subtalar dislocations. The present retrospective study included 13 patients who had sustained isolated subtalar dislocations during a 10-year period. Of the 13 cases, 10 (76.9%) were medial dislocations and 3 (23.1%) were lateral dislocations. All the patients underwent immediate closed reduction under anesthesia followed by immobilization. No open reduction was required. The mean follow-up period was 72.6 (range 24.4 to 124.8) months. The mean American Orthopaedic Foot and Ankle Society ankle-hindfoot score was 80.1 of 100 (range 66 to 90). The score result was good in 69% of cases and poor in 31% of cases. The subtalar mobility was reduced for 8 (61.5%) patients and significantly affected the American Orthopaedic Foot and Ankle Society score (p = .002). Subtalar osteoarthritis was present in 6 (46.1%) cases with talonavicular osteoarthritis in 3 (23.1%) cases. No cases of avascular necrosis of the talus were noted. In accordance with the published data, the prognosis of isolated acute traumatic subtalar dislocations is favorable. Medial dislocations are more frequent than lateral dislocations. Emergent closed reduction makes it possible to remove soft tissue injuries. The risk of post-traumatic subtalar osteoarthritis is significant, even without an initial subtalar lesion. A postreduction computed tomography scan will enable the diagnosis of osteochondral lesions.

Acrylic kyphoplasty in recent nonosteoporotic fractures of the thoracolumbar junction: a prospective clinical and 3D radiologic study of 54 patients.

STUDY DESIGN: Prospective clinical and radiological study. OBJECTIVES: To evaluate the impact of stand-alone acrylic kyphoplasty in the treatment of recent traumatic fractures of the thoracolumbar spine in young patients. SUMMARY OF BACKGROUND DATA: The management of fractures of the thoracolumbar spine without neurological deficit remains controversial. For a long time clinicians could only chose between functional treatment, orthopedic treatment, and traditional surgery. The recent advent of minimally invasive surgical techniques is an interesting alternative. MATERIALS AND METHODS: Fifty-four patients with a mean age of 45.8±18.2 years and who had recently sustained a fracture of the thoracolumbar junction were enrolled into the study. Balloon kyphoplasty was performed using acrylic cement. Radiologic assessments (computed tomography scans) and clinical assessments (including Visual Analog Scale and Oswestry Disability Index scores) were used to determine kyphoplasty success and measure patient recovery over 2 years. RESULTS: Kyphoplasty reduced mean vertebral kyphosis from 12.8±5.0 degrees at trauma to 8.2±5.1 degrees at 2-year follow-up. Mean vertebral kyphosis was corrected by -5.7±4.7 degrees (P=0.0001) at the point of first verticalization, with no significant change at the 2-year follow-up visit (+1.1±4.3 degrees, P=0.1058). Kyphoplasty significantly augmented the height of the 6 anterior and intermediate segments. Maximum mean augmentation of intermediate vertebral height after 6 months was (11.6%±15.5%, P<0.0001). Patients tolerated the procedure well and 56% of them returned to work 3 months after kyphoplasty. CONCLUSION: Kyphoplasty is safe and effective in the correction of nonosteoporotic fractures of the thoracolumbar junction in young patients, and remains stable for at least 2 years postsurgery.

Percutaneous treatment of tibial plateau fractures.

In France, 11,294 proximal tibia fractures occurred in 2018 and 6880 surgical procedures were done to treat them. Most of these were tibial plateau fractures, although fractures can occur in the metaphysis only or in the intercondylar eminence. The proximal tibia's poor vascularization justifies sparing it by doing a percutaneous treatment, setting the stage for bone union. The treatment must be based on rigorous planning with 3D imaging to determine the type of fracture accurately. The goals of treatment are first to realign the lower limb and then to reduce the articular surface, while addressing any associated injuries. Percutaneous reduction is based on ligamentotaxis and the use of spatulas or balloons that spare the vascularization. Surgical navigation and arthroscopy are precious tools for verifying the reduction. There are several options for stabilization, ranging from using polymethylmethacrylate cement for a Schatzker III fracture to applying a cannulated screw or doing MIPPO (Minimal Invasive Percutaneous Plate Osteosynthesis) with an anatomical plate and adjustable locking screws placed under the depression in complex fractures. Percutaneous surgery is not about the size of the incisions; the focus is on sparing the metaphysis and its vascularization to ensure high-quality and long-lasting stability. It appears to yield better functional outcomes than open reduction and internal fixation, not only for Schatzker type I, II and III fractures, but also for complex fractures where open fixation is more damaging and the source of complications.

Impact of time to surgery in upper femoral fracture in orthogeriatrics.

INTRODUCTION: Treatment of hip fracture in the elderly is a major public health issue. Orthogeriatric departments have been developed for these patients at high risk of complications. Time to surgery seems to be an important factor in the care pathway, but remains controversial. OBJECTIVES: The aim of this study was to assess the impact of less than 24 hours' time to surgery on 1-year morbidity and mortality in patients managed in our orthogeriatric department. HYPOTHESIS: The study hypothesis was that<24 hours' time to surgery decreases mortality in elderly patients with upper femoral fracture. MATERIALS AND METHODS: A retrospective cohort study from September 2015 to July 2016 included patients aged 75 years and older, eligible for orthogeriatric management of upper femoral fracture. Patients with comorbidities were prioritized for admission and for access to the operating room. Time to surgery was defined as time between the arrival in A&E and transfer to the operating room. The primary endpoint was 1-year survival. Comorbidities were assessed on Charlson score. ROC curve analysis determined the optimal cut-off for time to surgery. Variables significantly associated with mortality were included in a Cox regression model to estimate the adjusted effect of time to surgery on mortality. RESULTS: One hundred and eight patients were included; mean age, 87±6.2 years; 26 male (24.1%), 82 female (75.9%). One-year mortality was 24.1% (26/108). Mean time to surgery was 14.1±30.9hours. ROC curve analysis showed a rise in mortality after a cut-off of 22hours 37minutes (p<0.0001). CONCLUSION: Within a dedicated orthogeriatric department, time to surgery is a significant factor in the management of hip fractures in the elderly. Patients should be prioritized for theater and ideally receive "early" surgery within 24hours of admission to A&E. The potential benefit of "ultra-early" surgery (time to surgery<6hours) requires robust assessment. LEVEL OF EVIDENCE: IV, Retrospective cohort study.

Comparative evaluation of minimally invasive 'tibial tuberoplasty' surgical technique versus conventional open surgery for Schatzker II-III tibial plateau fractures: design of a multicentre, randomised, controlled and blinded trial (TUBERIMPACT study).

INTRODUCTION: Fractures of the tibial plateau are in constant progression. They affect an elderly population suffering from a number of comorbidities, but also a young population increasingly practicing high-risk sports. The conventional open surgical technique used for tibial plateau fractures has several pitfalls: bone and skin devascularisation, increased risks of infection and functional rehabilitation difficulties. Since 2011, Poitiers University Hospital is offering to its patients a new minimally invasive technique for the reduction and stabilisation of tibial plateau fractures, named 'tibial tuberoplasty'. This technique involves expansion of the tibial plateau through inflation using a kyphoplasty balloon, filling of the fracture cavity with cement and percutaneous screw fixation. We designed a study to evaluate the quality of fracture reduction offered by percutaneous tuberoplasty versus conventional open surgery for tibial plateau fracture and its impact on clinical outcome. METHODS AND ANALYSIS: This is a multicentre randomised controlled trial comparing two surgical techniques in the treatment of tibial plateau fractures. 140 patients with a Schatzker II or III tibial plateau fracture will be recruited in France. They will be randomised either in tibial tuberoplasty arm or in conventional surgery arm. The primary outcome is the postoperative radiological step-off reduction blindly measured on CT scan (within 48 hours post-op). Additional outcomes include other radiological endpoints, pain, functional abilities, quality of life assessment and health-economic endpoints. Outcomes assessment will be performed at baseline (before surgery), at day 0 (surgery), at 2, 21, 45 days, 3, 6, 12 and 24 months postsurgery. ETHICS AND DISSEMINATION: This study has been approved by the ethics committee Ile-De-France X and will be conducted in accordance with current Good Clinical Practice (GCP) guidelines, Declaration of Helsinki and standard operating procedures. The results will be disseminated through presentation at scientific conferences and publication in peer-reviewed journals. TRIAL REGISTRATION NUMBER: Clinicaltrial.gov:NCT03444779.

Biomechanical study and digital modeling of traction resistance in posterior thoracic implants.

STUDY DESIGN: Posterior implants were used to test the resistance of seven human thoracic spines to traction, and results were compared with those of a digital study. OBJECTIVES: To compare the use of hook and screw fixation methods for posterior thoracic surgery in a study supplemented by a digital analysis using the finite-element method. SUMMARY OF BACKGROUND DATA: The maximum break strength of pedicular screws on bone has already been studied several times. Far fewer studies have investigated the stresses that may be applied to pedicular and laminar hooks or compared these hooks with pedicular screws in the thorax. METHODS: For this study, seven human thoracic spines were used, identifying 49 groups of two vertebrae each. The assemblies used a bolt in the medullary cavity. The central diameter of this bolt could be varied using tubes to suit the individual medullary cavity, spreading the stresses over the entire centrum during traction. The assembly was placed on an Instron machine. Vertical traction was applied up to the maximum break strength, that is, the strength recorded at the top of the traction curve read out directly on the Instron machine. Traction speed in all the tests was 5 mm per minute. Four pedicular screws and two pedicular-laminar clips were used alternately. In these tests, 25 values were obtained with hooks and 24 with screws. The group with screw fixation was tested in two halves, with 12 tests using 4-mm diameter screws and 12 tests using 5-mm diameter screws. For the digital study, the vertebra model comprised nearly 63,000 nodes and 14,000 elements. Elastic field calculations were carried out using the Abaqus finite-element calculation method. RESULTS: Each time pedicular-laminar traction was used, the pedicles broke at the base. Where screws were used, a medial fissure was found at the base of the pedicle. For the hooks, the maximum break strength was 1150 +/- 388 N. It was 820 +/- 418 N when 4-mm diameter screws were used and 1395 +/- 435 N when 5-mm screws were used. The most fragile vertebrae were found to be at T5-T6 and T7-T8. The screw-instrumented model showed that stresses were concentrated at the medial part of the pedicle, inside the medullary cavity. Use of a long screw did not lead to noticeable stress reduction. The hook-instrumented model showed that the stresses were greatest in the lower part of the pedicles. CONCLUSIONS: Screw fixation is the most appropriate from a mechanical point of view. During tests, however, screw fixation falls short of its promises. This leads to the hypothesis that in most cases screws pull out because the bony anchoring of the pedicle screwing fails. Screws are less effective if their anchoring in the pedicles cannot be guaranteed, which is probably the reason for their relative weakness. Screw diameter should be chosen according to the size of each pedicle. The findings showed that hooks impose additional stresses on the vertebrae.