Shoulder injuries in polytraumatized patients: an analysis of the TraumaRegister DGU®.

Background: The aim of the present study was to analyze the prevalence, epidemiology and relevance of shoulder injuries in polytraumatized patients in a large national trauma database. We hypothesize a high prevalence of shoulder injuries in traffic accidents and a high prevalence of concomitant injuries of the thorax leading to an aggravated clinical course and higher Injury Severity Score (ISS). Furthermore, we hypothesize an increased rate of surgical treatment with the severity of the injury.

Reverse total shoulder arthroplasty for type I fracture sequelae after internal fixation of proximal humerus fractures.

Introduction: Complications after internal fixation of proximal humerus fracture are common and may require surgical revision. Reverse total shoulder arthroplasty (RTSA) is frequently performed in such cases. The aim of the present study was to evaluate the functional results and complications after RTSA for the treatment of type I fracture sequelae after internal fixation of proximal humerus fractures.

PEEK versus titanium locking plates for proximal humerus fracture fixation: a comparative biomechanical study in two- and three-part fractures.

Introduction: The high rigidity of metal implants may be a cause of failure after fixation of proximal humerus fractures. Carbon fiber-reinforced polyetheretherketone (PEEK) plates with a modulus similar to human cortical bone may help to overcome this problem. The present study assesses the biomechanical behavior of a PEEK plate compared with a titanium locking plate.

Screw augmentation reduces motion at the bone-implant interface: a biomechanical study of locking plate fixation of proximal humeral fractures.

Background: Shear forces at the bone-implant interface lead to a loss of reduction after locking plate fixation of proximal humeral fractures. The aim of the study was to analyze the roles of medial support screws and screw augmentation in failure loads and motion at the bone-implant interface after locking plate fixation of proximal humeral fractures.

Methods: Unstable 3-part fractures were simulated in 6 pairs of cadaveric humeri and were fixed with a DiPhos-H locking plate (Lima Corporate, Udine, Italy).

How to enhance the stability of locking plate fixation of proximal humerus fractures? An overview of current biomechanical and clinical data.

Background: The complication rate after locking plate fixation of proximal humerus fractures is high. In addition to low bone mineral density, a lack of medial support has been identified as one of the most important factors accounting for mechanical instability. As a result of the high failure rate, different strategies have been developed to enhance the mechanical stability of locking plate fixation of proximal humerus fractures.

Treatment of proximal humerus fractures with a CFR-PEEK plate: 2-year results of a prospective study and comparison to fixation with a conventional locking plate.

Background: A radiolucent carbon fiber-reinforced polyetheretherketone (CFR-PEEK) plate was recently introduced for fixation of proximal humerus fractures. Prospective clinical and radiographic results of patients treated with a CFR-PEEK plate are compared with those of patients treated with a conventional locking plate.

Methods: Twenty-nine patients (mean age, 66 years) were treated with a CFR-PEEK plate for a 3- or 4-part proximal humerus fracture.

Combination of a floating clavicle and a posterior shoulder dislocation: An "Unhappy Triad" of the shoulder girdle.

We present a case of a 31-year-old man who suffered from a floating clavicle in combination with a reverse Hill-Sachs lesion of his right shoulder girdle after a bicycle accident. Operative treatment was performed using minimal-invasive and arthroscopically assisted techniques. We strongly recommend an early CT scan with later 3-dimensional reconstruction to detect and fully understand these complex injuries.

Use of cell-free collagen type I matrix implants for the treatment of small cartilage defects in the knee: clinical and magnetic resonance imaging evaluation.

Purpose: Articular cartilage defects of the knee are a common condition for which several repair techniques have been described. The aim of the present study was to assess medium-term results of a one-step procedure using a cell-free collagen type I matrix.

Methods: Fifteen patients with articular cartilage defects of the knee were treated with an 11-mm-diameter cell-free collagen type 1 matrix implant.

Why does minimally invasive coracoclavicular ligament reconstruction using a flip button repair technique fail? An analysis of risk factors and complications.

Purpose: Aim of the present study was to evaluate the risk factors for the failure of coracoclavicular ligament reconstruction using a flip button repair technique and to analyse complications related to this procedure.

Methods: Seventy-one patients (3 female, 68 male) underwent surgical treatment using a flip button repair technique for an acute acromioclavicular joint dislocation. The following factors and its impact on clinical and radiographic outcome were assessed: age at trauma, interval between trauma and surgery, degree of displacement (according to Rockwood's classification), coracoid button position, button migration and post-operative appearance of ossifications.

Functionalisation of PLLA nanofiber scaffolds using a possible cooperative effect between collagen type I and BMP-2: impact on colonization and bone formation in vivo.

The reconstruction of large bone defects after injury or tumor resection often requires the use of bone substitution. Artificial scaffolds based on synthetic biomaterials can overcome disadvantages of autologous bone grafts, like limited availability and donor side morbidity. Among them, scaffolds based on nanofibers offer great advantages.

Cell-free collagen type I matrix for repair of cartilage defects-clinical and magnetic resonance imaging results.

Purpose: Several well-described techniques are available for the treatment of chondral and osteochondral defects. The aim of the study was to assess the efficacy of a single-stage procedure incorporating a new cell-free collagen type I gel for the treatment of small chondral and osteochondral defects in the knee evaluated at 2-year follow-up.

Methods: Fifteen patients were treated with a cell-free collagen type I gel matrix of 11 mm diameter.

Electrospun PLLA nanofiber scaffolds and their use in combination with BMP-2 for reconstruction of bone defects.

Introduction: Adequate migration and differentiation of mesenchymal stem cells is essential for regeneration of large bone defects. To achieve this, modern graft materials are becoming increasingly important. Among them, electrospun nanofiber scaffolds are a promising approach, because of their high physical porosity and potential to mimic the extracellular matrix (ECM).

Functionalisation of PLLA nanofiber scaffolds using a possible cooperative effect between collagen type I and BMP-2: impact on growth and osteogenic differentiation of human mesenchymal stem cells.

Mesenchymal stem cell differentiation of osteoblasts is triggered by a series of signaling processes including integrin and bone morphogenetic protein (BMP), which therefore act in a cooperative manner. The aim of this study was to analyze whether these processes can be remodeled in an artificial poly-(L)-lactide acid (PLLA) based nanofiber scaffold. Matrices composed of PLLA-collagen type I or BMP-2 incorporated PLLA-collagen type I were seeded with human mesenchymal stem cells (hMSC) and cultivated over a period of 22 days, either under growth or osteoinductive conditions.

TKA following high tibial osteotomy versus primary TKA--a matched pair analysis.

Background: High tibial osteotomy (HTO) is a well established technique for the treatment of medial osteoarthritis of the knee with varus malalignment. Results of total knee arthroplasty (TKA) after previous HTO are still discussed controversially. The aim of this study was to elucidate the clinical and radiological results as well as perioperative data of prior HTO on TKA.

Co-occurrence of outlet impingement syndrome of the shoulder and restricted range of motion in the thoracic spine--a prospective study with ultrasound-based motion analysis.

Background: Shoulder complaints, and especially the outlet-impingement syndrome, are a common condition. Among other things, poor posture has been discussed as a cause. A correlation between impingement syndrome and restricted mobility of the thoracic spine (T) has been described earlier, but there has been no motion analysis of the thoracic spine to show these correlations.

Influence of nanofibers on growth and gene expression of human tendon derived fibroblast.

Background: Rotator cuff tears are a common and frequent lesion especially in older patients. The mechanisms of tendon repair are not fully understood. Common therapy options for tendon repair include mini-open or arthroscopic surgery.

Influence of poly-(L-lactic acid) nanofiber functionalization on maximum load, Young's modulus, and strain of nanofiber scaffolds before and after cultivation of osteoblasts: an in vitro study.

The aim of this study was to characterize the influence of functionalization of synthetic poly-(L-lactic acid) (PLLA) nanofibers on mechanical properties such as maximum load, elongation, and Young's modulus. Furthermore, the impact of osteoblast growth on the various nanofiber scaffolds stability was determined. Nanofiber matrices composed of PLLA, PLLA-collagen, or BMP-2-incorporated PLLA were produced from different solvents by electrospinning.

RGD-functionalisation of PLLA nanofibers by surface coupling using plasma treatment: influence on stem cell differentiation.

The aim of this study was to functionalize the surface of synthetic poly-(l-lactic) (PLLA) nanofibers with RGD peptide, in order to promote growth and osteogenic differentiation of human mesenchymal stem cells (hMSC) in vitro. The cRGD was coupled onto PLLA nanofibers using oxygen plasma combined with EDC/sulfo-NHS activation. Matrices were seeded with hMSC and cultivated over a period of 22 days under growth conditions and analyzed during the course of cultivation.