Cement-augmented anterior screw fixation of Type II odontoid fractures in elderly patients with osteoporosis

Background contextClosed reduction and internal fixation by an anterior approach is an established option for operative treatment of displaced Type II odontoid fractures. In elderly patients, however, inadequate screw purchase in osteoporotic bone can result in severe procedure-related complications.PurposeTo improve the stability of odontoid fracture screw fixation in the elderly using a new technique that includes injection of polymethylmethacrylat (PMMA) cement into the C2 body.Study designRetrospective review of hospital and outpatient records as well as radiographs of elderly patients treated in a university hospital department of orthopedic surgery.Patient sampleTwenty-four elderly patients (8 males and 16 females; mean age, 81 years; range, 62–98 years) with Type II fractures of the dens.Outcome measuresComplications, cement leakage (symptomatic/asymptomatic), operation time, loss of reduction, pseudarthrosis and revision surgery, patient complaints, return to normal activities, and signs of neurologic complications were all documented.MethodsAfter closed reduction and anterior approach to the inferior border of C2, a guide wire is advanced to the tip of the odontoid under biplanar fluoroscopic control. Before the insertion of one cannulated, self-drilling, short thread screws, a 12 gauge Yamshidi cannula is inserted from anterior and 1 to 3 mL of high-viscosity PMMA cement is injected into the anteroinferior portion of the C2 body. During polymerization of the cement, the screws are further inserted using a lag-screw compression technique. The cervical spine then is immobilized with a soft collar for 8 weeks postoperatively.ResultsAnatomical reduction of the dens was achieved in all 24 patients. Mean operative time was 64 minutes (40–90 minutes). Early loss of reduction occurred in three patients, but revision surgery was indicated in only one patient 2 days after primary surgery. One patient died within the first eight postoperative weeks, one within 3 months after surgery. In five patients, asymptomatic cement leakage was observed (into the C1–C2 joint in three patients, into the fracture in two). Conventional radiologic follow-up at 2 and 6 months confirmed anatomical healing in 16 of the19 patients with complete follow-up. In two patients, the fractures healed in slight dorsal angulation; one patient developed a asymptomatic pseudarthrosis. All patients were able to resume their pretrauma level of activity.ConclusionsCement augmentation of the screw in Type II odontoid fractures in elderly patients is technically feasible in a clinical setting with a low complication rate. This technique may improve screw purchase, especially in the osteoporotic C2 body.     

Novel organ‐slice culturing system to simulate meniscal repair: Proof of concept using a synovium‐based pool of meniscoprogenitor cells

Meniscal injuries can occur secondary to trauma or be instigated by the changes in knee‐joint function that are associated with aging, osteo‐ and rheumatoid arthritis, disturbances in gait, and obesity. Sixty percent of persons over 50 years of age manifest signs of meniscal pathology. The surgical and arthroscopic measures that are currently implemented to treat meniscal deficiencies bring only transient relief from pain and effect but a temporary improvement in joint function. Although tissue‐engineering‐based approaches to meniscal repair are now being pursued, an appropriate in‐vitro model has not been conceived. The aim of this study was to develop an organ‐slice culturing system to simulate the repair of human meniscal lesions in vitro. The model consists of a ring of bovine meniscus enclosing a chamber that represents the defect and reproduces its sequestered physiological microenvironment. The defect, which is closed with a porous membrane, is filled with fragments of synovial tissue, as a source of meniscoprogenitor cells, and a fibrin‐embedded, calcium‐phosphate‐entrapped depot of the meniscogenic agents BMP‐2 and TGF‐β1. After culturing for 2 to 6 weeks, the constructs were evaluated histochemically and histomorphometrically, as well as immunohistochemically, for the apoptotic marker caspase 3 and collagen types I and II. Under the defined conditions, the fragments of synovium underwent differentiation into meniscal tissue, which bonded with the parent meniscal wall. Both the parent and the neoformed meniscal tissue survived the duration of the culturing period without significant cell losses. The concept on which the in‐vitro system is based was thus validated. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:1588–1596, 2016.     

Multicenter prospective randomized study comparing the technique of using a bovine pericardium biological prosthesis reinforcement in parietal herniorrhaphy (Tutomesh TUTOGEN) with simple parietal herniorrhaphy,in a potentially contaminated setting

The use of parietal synthetic prosthetic reinforcement material in potentially contaminated settings is not recommended, as there is a risk that the prosthesis may become infected. Thus, simple parietal herniorrhaphy, is the conventional treatment, even though there is a significant risk that the hernia may recur. Using new biomaterials of animal origin presently appears to offer a new therapeutic solution, but their effectiveness has yet to be demonstrated. The purpose of this multicenter prospective randomized single‐blind study was to compare the surgical treatment of inguinal hernia or abdominal incisional hernia by simple parietal herniorrhaphy without prosthetic reinforcement (Group A), with Tutomesh TUTOGEN biological prosthesis reinforcement parietal herniorrhaphy (Group B), in a potentially contaminated setting. We examined early postoperative complications in the first month after the operation, performed an assessment after one year of survival without recurrence and analyzed the quality of life and pain of the patients (using SF‐12 health status questionnaire and Visual Analog Pain Scale) at 1, 6, and 12 months, together with an economic impact study. Hundred and thirty four patients were enrolled between January 2009 and October 2010 in 20 French hospitals. The groups were comparable with respect to their enrollment characteristics, their history, types of operative indications and procedures carried out. At one month post‐op, the rate of infectious complications (n(A) = 11(18.33%) vs. n(B) = 12(19.05%), p = 0.919) was not significantly different between the two groups. The assessment after one year of survival without recurrence revealed that survival was significantly greater in Group B (Group A recurrence: 10, Group B: 3; p = 0.0475). No difference in the patients' quality of life was demonstrated at 1, 6, or 12 months. However, at the 1 month follow‐up, the “perceived health” rating seemed better in the group with Tutomesh (p = 0.022). No significant difference between the two parietal repair groups was observed during the follow‐ups with respect to the criterion of pain (using a visual analog scale). There was a significant difference between the two parietal repair groups with regard to the number of days spent in intensive care unit, in favor of the Tutomesh technique (p = 0.010). The use of a Tutomesh bioprosthesis for hernia repair or postincisional hernia in a potentially contaminated workplace reduces the risk of short‐term recurrence without increasing overall comorbidity.     

Major retinal autoantigens remain stably expressed during all stages of spontaneous uveitis

Equine recurrent uveitis (ERU) is a valuable model for autoimmune diseases, since it develops frequently and occurs spontaneously. We investigated the overall expression level of three major retinal autoantigens in normal retinas and various ERU stages. Analysis of retinal proteomes of both, healthy and diseased retinas revealed an almost unaffected expression of IRBP, S-antigen and cRALBP in ERU cases. Validation of these findings with western blots and immunohistochemistry confirmed constant to increased expression of these autoantigens, although loss of their physiological expression sites within retina is evident. In contrast to stable expression of autoantigens, rhodopsin, the major component of phototransduction in photoreceptors, disappeared from destructed retinas. These results explain persistent uveitic attacks even in severely damaged eyes and draw the attention to further investigations of biological pathways and regulations in autoimmune target tissues.