• Lindgaard Lassen posted an update 2 days, 14 hours ago

    Orthopaedic literature on hip arthroscopy has become more robust primarily from the advent and transformation in the treatment of femoroacetabular impingement syndrome from an open surgical dislocation to an ambulatory arthroscopic procedure. Numerous studies have reviewed the frequency of authors and subjects in particular areas of arthroscopy, but until this article, none had been performed on the most influential in hip arthroscopy. The question to be answered is, Do such studies contribute significantly to our knowledge by suggesting future topics to clinicians and training programs? The viscoelastic properties of suture may impact how soft tissue (such as the shoulder rotator cuff tendons) heals to bone and therefore may impact patient outcomes. Thus, it is logical to use suture material less likely to creep and elongate. Suture tape, in particular, may show superior biomechanical properties compared with standard sutures. However, in cadaveric studies, failure generally occurs at the tissue interface, rather than the suture material (or anchor). Thus, the quality and thickness of local tissue must be taken into consideration when determining postoperative rehabilitation or return to activity. Clinical outcome studies comparing suture materials remain elusive, but there is little reason not to use stronger suture material, and this is an option within the surgeon’s control. Latarjet technique via open or arthroscopic approach is a very complex surgery that includes several steps. The coracoid placement that is performed at the end of this procedure represents the key point to avoid complications and attain the best clinical results. Mechanics and biology need to work as a whole to improve the integration of the graft on the glenoid neck. Superior capsular reconstruction remains a controversial procedure, and long-term results still need to be established. Graft thickness seems crucial and fascia lata appears superior to dermal allograft. Using a subacromial spacer by suturing dermal allograft to the subacromial bone “increases graft thickness” and reduces superior humeral head migration but increases subacromial pressures in a static laboratory cadaver model. It remains to be seen whether clinical studies support this concept. Risk factors of failure after arthroscopic posterior shoulder stabilization are not well understood. Careful attention to anatomy may be the key to helping patients understand their risk of failure after surgery. Posterior stabilization may be even more sensitive to small amounts of bone loss than is anterior stabilization. As failure rates after arthroscopic rotator cuff remain high, platelet-rich plasma (PRP) has gained interest as a potential biological augmentation to enhance bone-tendon healing. Recent research shows that delayed PRP application fails to significantly improve clinical results or decrease retear rates but may result in less fatty-infiltration of the repaired rotator cuff muscles. In combination with a lower trend toward retear, this may hint that we should not bid farewell to PRP in rotator cuff repair just yet, and whether our current enthusiasm for emerging biological strategies in rotator cuff repair is justified remains subject to additional investigation. After rotator cuff repair, the regeneration of the anatomic enthesis may be beneficial. Although many cell and growth factor studies have been performed, none have shown a consistent regeneration of this structure. The use of bone marrow vents in the greater tuberosity has been associated with improved healing. The resultant clot has been dubbed a “crimson duvet” or blanket. The use of this readily available-and inexpensive-modality should be maximized in patients undergoing rotator cuff repair. In the end, a goal could be to enhance tendon-to-bone healing via a scaffold, cells, and growth factors. Pending inevitable reliable advances in biological augmentation, mesenchymal stem cells and growth factors from the greater tuberosity are just a marrow-stimulating pick away. Clinical databases allow researchers to test multiple hypotheses. This could result in including outcomes on the same patient or patients in more than 1 study. When this occurs, it is vital for authors to clarify multiple reporting in their study methods to avoid having patients counted more than once in future systematic reviews or meta-analyses. As a caveat, primary authors should consider whether publication of multiple studies is important or whether they are simply generating “least publishable units” (LPUs, also known as salami slicing). In order to suppress the influence of lumped system disturbance, such as external disturbance and internal disturbance caused by model mismatch and coupling between variables, more effectively, a multivariable non-minimum state space predictive control method based on disturbance observer (MNMSSPC-D) is proposed in this paper. Most of the existing methods based on the feedback control and feedforward compensation cannot guarantee optimal output. Unlike the existing methods, the proposed method extends the estimated disturbance and output variables into the state variables, forming a multivariable non-minimum state space (MNMSS) prediction model, and then uses the rolling optimization principle in predictive control to design the controller based on the formed prediction model. The main advantages of the proposed method are that the state can be guaranteed to be available to the MNMSS model and the optimal control performance and anti-disturbance ability of system can be obtained by the designed controller. The proposed MNMSSPC-D method is verified by the simulation with a heavy oil fractionator. In this paper, a new robust adaptive estimation approach is designed for the inverted pendulum. click here The estimation scheme is composed by an auxiliary high gain observer in cascade with an adaptive sliding mode observer. The auxiliary high gain observer is designed to estimate auxiliary outputs in order to solve the dissatisfaction of observer matching condition related to the presence of disturbances. Then, using the estimated auxiliary outputs, the adaptive sliding mode observer is synthesized to estimate conjointly the states, the unknown parameter (the pendulum mass which appears nonlinearly in the dynamics of the pendulum model) and the unknown disturbances. The stability analysis is established using the Lyapunov approach. Numerical simulations are carried out to validate theoretical results. Furthermore, experimental tests are realized using a real pendulum setup (a product of Feedback Instruments) to highlight the good performances of the proposed estimation method in practice.