Der Unfallchirurg
-
Injuries to ligaments and tendons heal by formation of inferior repair tissue. This may result in severe joint dysfunction. Because of an increased occurrence of sports-related injuries, musculoskeletal disorders may become one of the major burden of health care. ⋯ The benefits of using mesenchymal stem cells on a three dimensional biological matrix have been shown recently. Tissue engineering will also include mechanical manipulation of tissue environments to accelerate cell differentiation and to improve matrix formation. Fibroblast-seeded polymer scaffolds could be useful in ligament and tendon replacement in which autogenous fibroblasts would be obtained through biopsy, cultured and seeded onto a scaffold.
-
Undisplaced fractures of the proximal radius can generally be treated conservatively with good results. In children, spontaneous correction of some angular deformities can be expected during growth. Nevertheless, more severely displaced fracture types may require reduction in children, too. ⋯ A technique of percutaneous fracture reduction is demonstrated that can provide good results in cases when closed techniques have failed. A Kirschner wire is used to manipulate the fracture fragments percutaneously, which can often prevent open techniques. An additionally performed elastic-stable intramedullary nailing can add to an effective stabilisation and encourage to early physiotherapy.
-
One major problem using small diameter nails in the treatment of tibial fractures is the high rate of fatigue fractures of the locking screws. The objective of this study was to develop a mathematical model for analysis of the stress concentration factor as well as edge fibre stress. This would allow an analysis of the stress peaks caused by the thread of the screw as well as showing ways to increase the fatigue limits of the screws. ⋯ To improve the fatigue limit of locking screws one has to modify the stress concentration factor or the edge fibre stress on the implant. Absence of a thread at the location where the screw contacts the nail's aperture (where the main load is transmitted to the screw and where the screw therefore usually tends to break) may double the fatigue strength and fatigue limit by avoiding the negative notch effect of the screw's thread. If this option is not possible one has to consider that the optimal threaded screw should have a minimal edge distance, a high notch radius and a minimal edge depth.
-
We treated 11 patients with primary sarcoma and 1 patient with enchondroma of the femur or tibia. Bridging the osseus defect we used an intercalary allograft shell and contralateral fibula as described by Capanna et al. [7]. The median bone defect after resection of the tumor was 15.7 (9.0-28.5) cm, average follow up was 29.2 (13-56) month. ⋯ There were 3 cases necessitating later amputation. The other cases showed good clinical (Enneking-score) and radiological (ISOLS-score) results. These results indicate the described technique as a suitable method for defect reconstruction with good functional outcome.
-
This prospective consecutive study judges the effectiveness of pulsed low-intensity ultrasound for treatment of boney healing disorders. 86 out of 100 treatments were successful. Although in these 100 cases 64 delayed unions and 36 nonunions were enrolled ultrasound therapy was performed as an alternative to the indicated operation in every case. ⋯ Judging the healing rate of 86% one has to take into consideration that according to our in- and excluding criteria we had a preselected sample of patients. Nevertheless the effectiveness of pulsed low-intensity ultrasound for treatment of disorders of the fracture repair process is evident.