Fractures of the distal humerus in the adult comprise approximately one third of all humeral fractures. Successful management of distal humerus fractures depends on correct reduction of the fracture, reconstruction of the articular surface if needed, stability and rigidity of the fixation, and appropriate rehabilitation. In this review, we evaluated the available literature and highlighted current therapy concepts. We assessed the evolution of internal fixation and elbow arthroplasty focusing on the established surgical approaches against the background of a growing incidence of distal humeral fractures in an aging patient population. Therefore evaluating the aspect and influence of age-dependent comorbidities like osteoporosis on successful treatment.

Nasal chondrocytes (NC) were previously demonstrated to remain viable and to participate in the repair of articular cartilage defects in goats. Here, we investigated critical features of tissue-engineered grafts generated by NC in this large animal model, namely cell retention at the implantation site, architecture and integration with adjacent tissues, and effects on subchondral bone changes. In this study, isolated autologous goat NC (gNC) and goat articular chondrocytes (gAC, as control) were expanded, green fluorescent protein-labelled and seeded on a type I/III collagen membrane. After chondrogenic differentiation, tissue-engineered grafts were implanted into chondral defects (6 mm in diameter) in the stifle joint for 3 or 6 months. At the time of explantation, surrounding tissues showed no or very low (only in the infrapatellar fat pad <0.32%) migration of the grafted cells. In repair tissue, gNC formed typical structures of articular cartilage, such as flattened cells at the surface and column-like clusters in the middle layers. Semi-quantitative histological evaluation revealed efficient integration of the grafted tissues with the adjacent native cartilage and underlying subchondral bone. A significantly increased subchondral bone area, as a sign for the onset of osteoarthritis, was observed following treatment of cartilage defects with gAC-, but not with gNC-grafts. Our results reinforce the use of NC-based engineered tissue for articular cartilage repair and preliminarily indicate their potential for the treatment of early osteoarthritic defects.

The accumulation of senescent cells is implicated in the pathology of several age-related diseases. While the clearance of senescent cells has been suggested as a therapeutic target for patients with osteoarthritis (OA), cellular senescence of bone-resident osteoblasts (OB) remains poorly explored. Since oxidative stress is a well-known inducer of cellular senescence, we here investigated the effect of antioxidant supplementation on the isolation efficiency, expansion, differentiation potential, and transcriptomic profile of OB from osteoarthritic subchondral bone. Bone chips were harvested from sclerotic and non-sclerotic regions of the subchondral bone of human OA joints. The application of 0.1 mM ascorbic acid-2-phosphate (AA) significantly increased the number of outgrowing cells and their proliferation capacity. This enhanced proliferative capacity showed a negative correlation with the amount of senescent cells and was accompanied by decreased expression of reactive oxygen species (ROS) in cultured OB. Expanded cells continued to express differentiated OB markers independently of AA supplementation and demonstrated no changes in their capacity to osteogenically differentiate. Transcriptomic analyses revealed that apoptotic, cell cycle–proliferation, and catabolic pathways were the main pathways affected in the presence of AA during OB expansion. Supplementation with AA can thus help to expand subchondral bone OB in vitro while maintaining their special cellular characteristics. The clearance of such senescent OB could be envisioned as a potential therapeutic target for the treatment of OA.

Background A majority of proximal humeral fractures can be managed without surgery. Recent randomized clinical trials and meta-analyses even question the benefit of surgical treatment for displaced 3-, and 4-part fractures. However, evidence-based treatment recommendations, balancing benefits and harms, presuppose a common reporting of complications and adverse events, which at the moment is largely missing. Therefore we systematically reviewed the use of terms and definitions of complications after nonsurgical management of proximal humeral fractures. Methods We searched PubMed, EMBASE, Cochrane Library, Scopus and WorldCat (2010–2017) and included articles and book chapters containing complication terms or definitions. Two reviewers independently extracted and grouped terms and definitions according to a predefined scheme. Terms and definitions concerning non-surgical management were tabulated, grouped and analyzed qualitatively. Results The initial search identified 1376 references from which 470 articles were selected for full-text retrieval. Data-extraction included first articles published in 2017, was then performed iteratively in batches of 20 articles, and terminated after retrieval of 91 articles when no additional definitions or terms was found. In addition, 12 book chapters were reviewed from an initial list of 100. No general definition of a complication was found. A total of 69 terms for complications after non-surgical management were identified from 19 articles. Sixty-seven terms regarded local events. The most commonly reported event terms regarded osteonecrosis, malunion, secondary displacement and rotator cuff problems. Seven individual terms were accompanied by some kind of definition. Most terms and definitions were based on radiographical assessments. Conclusions We found no consensus in the use of terms and definitions of complications after nonsurgical management of proximal humeral fractures. Multiple terms, some synonymous, some partly synonymous, some distinct, were used. Few complication terms were explicitly defined. Development and validation of an internationally consensus-based core event set for complications after proximal humeral fractures managed non-surgically is needed. Electronic supplementary material The online version of this article (10.1186/s12891-019-2459-6) contains supplementary material, which is available to authorized users.