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Background: Mobile-bearing ankle implants with good clinical results continued to increase the popularity of total ankle arthroplasty to address endstage ankle osteoarthritis preserving joint movement. Alternative solutions used fixed-bearing designs, which increase stability and reduce the risk of bearing dislocation, but with a theoretical increase of contact stresses leading to a higher polyethylene wear. The purpose of this study was to investigate the contact stresses, pressure and area in the polyethylene component of a new total ankle replacement with a fixed-bearing design, using 3D finite element analysis., Methods: A three-dimensional finite element model of the Zimmer Trabecular Metal Total Ankle was developed and assembled based on computed tomography images. Three different sizes of the polyethylene insert were modeled, and a finite element analysis was conducted to investigate the contact pressure, the von Mises stresses and the contact area of the polyethylene component during the stance phase of the gait cycle., Results: The peak value of pressure was found in the anterior region of the articulating surface, where it reached 19.8 MPa at 40% of the gait cycle. The average contact pressure during the stance phase was 6.9 MPa. The maximum von Mises stress of 14.1 MPa was reached at 40% of the gait cycle in the anterior section. In the central section, the maximum von Mises stress of 10.8 MPa was reached at 37% of the gait cycle, whereas in the posterior section the maximum stress of 5.4 MPa was reached at the end of the stance phase., Discussion: The new fixed-bearing total ankle replacement showed a safe mechanical behavior and many clinical advantages. However, advanced models to quantitatively estimate the wear are need., Conclusion: To the light of the clinical advantages, we conclude that the presented prosthesis is a good alternative to the other products present in the market.

Purpose: Lack of the anterior cruciate ligament in total knee arthroplasty results in paradoxical movement of the femur as opposed to the tibia under deep flexion. Total knee arthroplasty with mobile-bearing inlays has been developed to provide increased physiological movement of the knee joint and to reduce polyethylene abrasion. The aim of this study was to perform an in vitro analysis of the kinematic movement in the sagittal plane in order to show differences between fixed- and mobile-bearing TKA in comparison with the natural knee joint., Methods: Seven knee joints of human cadaver material were used in a laboratory experiment. Fixed- and mobile-bearing inlays were tested in sequences under isokinetic extension in so-called kinemator for knee joints, which can simulate muscular traction power by the use of hydraulic cylinders, which crossover the knee joint. As a target parameter, the a.p. translation of the tibio-femoral relative movement was measured in the sagittal plane under ultrasound (Zebris) control., Results: The results show a reduced tibial a.p. translation in relation to the femur in the bearing group compared to the natural joint. In the Z-axis, between 110° and 50° of flexion, linear movement decreases towards caudal movement under extension. Admittedly, the study did not show differences in the movement pattern between "mobile-bearing" and "fixed-bearing" prostheses., Conclusion: Results of this study cannot prove functional advantages of mobile-bearing prostheses for the knee joint kinematic after TKA. Both types of prostheses show typical kinematics of an anterior instability, hence they were incapable of performing physiological movement.

Purpose: The purpose of this study was to assess the safety and preliminary clinical results of platelet-rich plasma (PRP) injections for treating chronic plantar fasciitis., Methods: Fourteen consecutive patients with chronic plantar fasciitis receiving three injections of PRP into the plantar fascia were assessed 12 months after the procedure. The modified Roles and Maudsley score and a visual analogue scale (VAS) for pain were used to evaluate the clinical results., Results: According to criteria of the Roles and Maudsley score, at 12 months of follow-up, results were rated as excellent in nine (64.3 %), good in two (14.3 %), acceptable in two (14.3 %) and poor in one (7.1 %) patient. VAS for pain was significantly decreased from 7.1 ± 1.1 before treatment to 1.9 ± 1.5 at the last follow-up (p < 0.01)., Conclusions: In this single-centre, uncontrolled, prospective, preliminary study, results indicate that treating chronic plantar fasciitis with PRP injections is safe and has the potential to reduce pain.

Nonunion of the first metatarsal after hallux valgus surgery is a rare complication that often results in significant pain and disability requiring surgical management. We report the case of a 42-year-old woman who developed a pseudarthrosis of the first metatarsal after percutaneous retrocapital distal osteotomy of the first metatarsal for a mild hallux valgus deformity. The operative treatment consisted of debridement of fibrous nonunion with plating followed by application of pulsed electromagnetic fields (PEMF) with an external device.

Plantar pressure characteristics during fencing movements may provide more specific information about the influence of foot loading on overload injury patterns. Twenty-nine experienced fencers participated in the study. Three fencing-specific movements (lunge, advance, retreat) and normal running were performed with three different shoe models: Ballestra (Nike, USA), Adistar Fencing Lo (Adidas, Germany), and the fencers' own shoes. The Pedar system (Novel, Munich, Germany) was used to collect plantar pressures at 50 Hz. Peak pressures, force-time integrals and contact times for five foot regions were compared between four athletic tasks in the lunge leg and supporting leg. Plantar pressure analysis revealed characteristic pressure distribution patterns for the fencing movements. For the lunge leg, during the lunge and advance movements the heel is predominantly loaded; during retreat, it is the hallux. For the supporting leg, during the lunge and advance movements the forefoot is predominantly loaded; during retreat, it is the hallux. Fencing-specific movements load the plantar surface in a distinct way compared with running. An effective cushioning in the heel and hallux region would help to minimize foot loading during fencing-specific movements.

Selective electrophysiological involvement of median motor fibers is rare in carpal tunnel syndrome. We report a patient with compression neuropathy of the median nerve who presented with isolated motor signs and symptoms without macroscopic evidence of compressive pathologies.