Validation of a new meniscal root repair technique that will be biomechanically superior to current gold standard procedures and, at the same time, will allow controlled adjustable fixation.

Medial and lateral meniscus from 10 porcine knees were collected. An iatrogenic posterior root tear was created and a single transosseous tibial tunnel technique that closely replicates the repair procedure with a 2-mm-wide-knottable braided tape was performed. Randomly, in one group (A) two simple cinch stitch were applied to suture the posterior root of the meniscus and, in the other group (B), a simple stich that holds the meniscus in two points in a crosse match configuration was used. For final fixation, alternating surgeon's knots (A group) and a doubled suture knot that allows an adjustable fixation were used (B group). All repairs were standardized for location and the repair stiches were placed in the body of the meniscus.

The new suture configuration (B group) showed a better biomechanical performance in terms of load for both the medial [151,0-560,3] 306,9±173,8N and the lateral posterior root fixation [268,2-463,1] 347,4±74,3N in comparison to the cinch stitch (A group) [219,0-365,2] 268,9±58,7N and [219,0-413,6] 318,0±72N. The maximum stiffness was also higher for the new tested suture configuration (B group) for both the medial meniscus [10,6-34,5] 18,9±9,2N/mm vs [7,1-12,7] 10,9±2,2N/mm and the lateral meniscus [16,0-27,9] 21,6±5,5N/mm vs [7,6-15,6] 12,6±3,5N/mm.

The presented new meniscal root repair is biomechanically superior to current gold standard techniques, as the cinch stich made with tape, keeping the simplicity and reproducibility of the procedure and, at the same time, is economically advantageous since a single tape in needed and allows adjustable fixation of the repair over a button.

Total shoulder arthroplasty is a well-tested procedure that offers pain relief and restores the joint function. However, failure rate is still high, and glenoid loosening is pointed as the main reason in orthopedic registers. In order to understand the principles of failure, the principal strain distributions after implantation with Comprehensive® Total Shoulder System of Biomet® were experimental and numerically studied to predict bone behavior.

Fourth generation composite left humerus and scapula from Sawbones® were used. These were implanted with Comprehensive® Total Shoulder System (Biomet®) with a modular Hybrid® glenoid base and Regenerex® glenoid and placed in situ by an experienced surgeon. The structures were placed in order to simulate 90º abduction, including principal muscular actions. Muscle forces used were as follows: Deltoideus 300N, Infraspinatus 120N, Supraspinatus 90N, Subscapularis 225N.

All bone structures were modeled considering cortical and the trabecular bone of the scapula. The components of prosthesis were placed in the same positions than those in the in vitro models. Geometries were meshed with tetrahedral linear elements, with material properties as follows: Elastic modulus of cortical bone equal to 16 GPa, elastic modulus of trabecular bone equal to 0.155 GPa, polyethylene equal to 1GPa and titanium equal to 110 GPa. The assumed Poisson's ratio was 0.3 in all except for polyethylene where we assumed a value of 0.4. The prosthesis was considered as glued to the adjacent bone. The finite element model was composed of 336 024 elements.

At the glenoid cavity, the major influence of the strain distributions was observed at the posterior-superior region, in both cortical and trabecular bone structures. The system presents critical region around holes of fixation in glenoid component. At the trabecular bone, the maximum principal strains at the posterior-superior region ranged from 2250 µε to 3000 µε. While at the cortical bone, the maximum principal strains were 300 µε to 400 µε.

The results observed evidence some critical regions of concern and the effect of implant in the bone strains mainly at the posterior-superior region of the glenoid cavity is pronounced. This indicates that this region is more affected by the implant if bone remodeling is a concern and it is due to the strain-shielding effect, which has been connected with loosening of the glenoid component.

The goal of this work is to evaluate the epidemiology and treatment employed in the treatment of pyogenic spondylodiscitis.

Diagnosis was based on clinical and imaging, it does not include cases of postoperative infection and lesions contiguous with decubitus ulcers. The clinical records were used to obtain demography, comorbidities, presenting symptoms, physical examination, laboratorial values, diagnostic procedures, microbiological profile as well as medical and surgical treatment. Statistical analysis was performed using SPSS 20.

After reviewing 22 patients met the inclusion criteria. The mean age was 60.82(range 22–86), 82 % were men(n=18). Most prevalent comorbidities were diabetes mellitus 41%(n=9), chronic alcoholism 18% (n=4), CKD 14%(n=3) and HIV in 9%(n=2). Approximately 40.1% had a septic focus in another location, the most common UTI 30%(n=3) and 20% sepsis(n=2). The most common symptoms were LBP 51%(n=21), weight loss 15%(n=6) and fever 12%(n=5). Laboratory evaluation revealed an average leukocytosis 11.8(range 4.3–21.8), ESR averaged 83.9 mm/h (range 10–128), mean CRP 11.6 mg/dl(range 0.4–38.7). The lumbar spine was the most affected segment 55%(n=12), then the dorsal 36%(n=8) and cervical 9%(n=2). The microbiological diagnosis was established in 55% of cases (n=12), 8(66.7%) cases were identified in blood cultures and 3(25%) in bone biopsy. The most common agents identified were MSSA in 18% of cases (n=4) and cogulase negative staphylococci 18%(n=4). A surgical procedure was performed in 86.4% (n=19), 7 for fusion and in 4 a transpedicular biopsy. The indications for surgery were crop material, abscess drainage and instability each with 32%(n=6). In terms of neurological sequelae 23%(n=5) had changes. The average length of stay was 57.4 days(range 19–190), mortality was 9%(n=2). We found no statistically significant differences regarding the identification of microorganisms using age (p=0.644), ESR(p=0.233), CRP(p=0.166) and leukocytosis(p=0.147) as variables.

Our series has characteristics common to literature, predominantly male, risk factors as Diabetes, CKD and HIV are common. Alcoholism is linked with some immunosuppression and appears as a new risk factor. Obtaining microbiological diagnosis is crucial to avoid the need for prolonged antibiotic therapy and the potential increased costs and toxicity of broad spectrum. The low number of positive biopsy (25%) is explained by the early empirical antibiotic therapy before sampling. Surgery plays an important role in crop products for microbiological analysis and treatment of instability or neurological deficits. A high index of suspicion in patients with known risk factors and back pain is crucial since delay in diagnosis leads to worse outcomes.