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Matrigel, a basement-membrane matrix extracted from Engelbreth-Holm-Swarm mouse sarcomas, has been used for more than four decades for a myriad of cell culture applications. However, Matrigel is limited in its applicability to cellular biology, therapeutic cell manufacturing and drug discovery owing to its complex, ill-defined and variable composition. Variations in the mechanical and biochemical properties within a single batch of Matrigel - and between batches - have led to uncertainty in cell culture experiments and a lack of reproducibility. Moreover, Matrigel is not conducive to physical or biochemical manipulation, making it difficult to fine-tune the matrix to promote intended cell behaviours and achieve specific biological outcomes. Recent advances in synthetic scaffolds have led to the development of xenogenic-free, chemically defined, highly tunable and reproducible alternatives. In this Review, we assess the applications of Matrigel in cell culture, regenerative medicine and organoid assembly, detailing the limitations of Matrigel and highlighting synthetic scaffold alternatives that have shown equivalent or superior results. Additionally, we discuss the hurdles that are limiting a full transition from Matrigel to synthetic scaffolds and provide a brief perspective on the future directions of synthetic scaffolds for cell culture applications.Cite this article EFORT Open Rev 2020;5519-521. DOI 10.1302/2058-5241.5.200300.The stability of the glenohumeral joint depends on soft tissue stabilizers, bone morphology and dynamic stabilizers such as the rotator cuff and long head of the biceps tendon. Tofacitinib supplier Shoulder stabilization techniques include anatomic procedures such as repair of the labrum or restoration of bone loss, but also non-anatomic options such as remplissage or tendon transfers.Rotator cuff repair should restore the cuff anatomy, reattach the rotator cable and respect the coracoacromial arch whenever possible. Tendon transfer, superior capsular reconstruction or balloon implantation have been proposed for irreparable lesions.Shoulder rehabilitation should focus on restoring balanced glenohumeral and scapular force couples in order to avoid an upward migration of the humeral head and secondary cuff impingement. The primary goal of cuff repair is to be as anatomic as possible and to create a biomechanically favourable environment for tendon healing. Cite this article EFORT Open Rev 2020;5508-518. DOI 10.1302/2058-5241.5.200006.The growth plate is the cartilaginous portion of long bones where the longitudinal growth of the bone takes place. Its structure comprises chondrocytes suspended in a collagen matrix that go through several stages of maturation until they finally die, and are replaced by osteoblasts, osteoclasts, and lamellar bone.The process of endochondral ossification is coordinated by chondrocytes and a variety of humoral factors including growth hormone, parathyroid hormone, oestrogen, growth factors, cytokines, and various signalling pathways.Chondrocytes progress from a resting state to enter the phases of proliferation and hypertrophy. Under the influence of oestrogen, the proliferation of chondrocytes decreases as the resting chondrocytes are consumed. During the terminal phase of differentiation, cartilage is replaced by blood vessels and organized bone tissue, and once chondrocytes have died, the longitudinal growth of the bone ceases and the growth plate closes.The highly complex regulatory signals involved in this process are genetically determined, and genetic perturbations in any of the associated genes can result in abnormalities of bone growth. Hundreds of chondrodysplasias have been described, pointing to the complexity of the humoral control systems involved in endochondral ossification.While our knowledge of the mechanisms behind the various bone growth control systems is improving, a deeper understanding of the underlying processes could aid clinicians to better understand bone health and bone growth abnormalities. This review describes the current clinical research into the physiology of the growth plate. Cite this article EFORT Open Rev 2020;5498-507. DOI 10.1302/2058-5241.5.190088.Although mechanical alignment (MA) has traditionally been considered the gold standard, the optimal alignment strategy for total knee arthroplasty (TKA) is still debated.Kinematic alignment (KA) aims to restore native alignment by respecting the three axes of rotation of the knee and thereby producing knee motion more akin to the native knee.Designer surgeon case series and case control studies have demonstrated excellent subjective and objective clinical outcomes as well as survivorship for KA TKA with up to 10 years follow up, but these results have not been reproduced in high-quality randomized clinical trials.Gait analyses have demonstrated differences in parameters such as knee adduction, extension and external rotation moments, the relevance of which needs further evaluation.Objective improvements in soft tissue balance using KA have not been shown to result in improvements in patient-reported outcomes measures.Technologies that permit accurate reproduction of implant positioning and objective measurement of soft tissue balance, such as robotic-assisted TKA and compartmental pressure sensors, may play an important role in improving our understanding of the optimum alignment strategy and implant position. Cite this article EFORT Open Rev 2020;5486-497. DOI 10.1302/2058-5241.5.190093.Trochanteric osteotomy is a technique that allows expanded exposure and access to the femoral canal and acetabulum for a number of indications.There has been renewed interest in variants of this technique, including the trochanteric slide osteotomy (TSO), extended trochanter osteotomy (ETO), and the transfemoral approach, for both septic and aseptic revision total hip arthroplasty (THA).Osteotomy fixation is crucial for achieving union, and wire and cable-plate systems are the most common techniques.TSO involves the creation of a greater trochanter fragment with preserved abductor attachment proximally and vastus lateralis attachment distally.This technique may be particularly useful in the setting of abductor deficiency or when augmented acetabular exposure is needed.ETO is a posterior-laterally based extensile approach that has been successfully utilized for aseptic and septic indications; most series report a greater than 90% rate of union.The transfemoral approach, as known as the Wagner osteotomy, is an extensile femoral approach and is more anterior-based than the alternate posterior-based ETO.