The measurement of fracture stiffness allows the detection of patients at risk for nonunions. The healing time increased with increasing fracture gap size and was less in patients with younger age, less complex fractures, and lesser degrees of soft tissue damage.

No abstract

The purpose of this article is to evaluate the incidence and to give a general review of the examination of the posterior ligament complex. At least ca. 8-10 % of all severe ligament injuries concern the posterior cruciate ligament, which means, that an estimated 4,000-5,000 Germans suffer a PCL rupture every year. Motor-vehicle accidents are the most common cause of the injury, but sports-related traumas (football, skiing) have increased in recent years. The high number of high-energy mechanisms involved (up to 90 %), cause ligament ruptures often to be associated with other injuries, especially fractures of the femur and tibia head. In polytrauma patients PCL ruptures are frequently recognized very late, because the possibility of this kind of injury is often not considered during the clinical examination. The same holds for the diagnosis of monotrauma patients. The initial step in the evaluation is to obtain a thorough history (including the mechanism of injury) and to perform a physical examination. The instability after a PCL rupture may present as an ACL rupture, because the anterior drawer test seems to be positive. The anterior/posterior drawer test must be assessed with other evaluation procedures to distinguish between anterior und posterior instabilities. The posterior sag sign, the quadriceps active test or the reversed pivot-shift may indicate a PCL rupture. A correct roentgenogram can reveal an avulsion of the tibia and can prove posterior instability due to a posterior translation of the tibia. A quantitative examination (clinical or X-ray) of the instability and the indication of combined injury of the posterior cruciate ligament and the posterolateral complex are necessary for the therapeutic decision (operative/conservative). A rupture of the PCL may occur occasionally as a result of a luxation of the knee (reduced spontaneously) before the medical evaluation. A thorough neurovascular examination is essential. Magnetic resonance imaging can be important to the diagnosis of an acute injury, but it is not essential for the choice between operative and non-operative treatment. Arthroscopy has been found to have a high degree of accuracy in the diagnosis of ligament ruptures of the knee, but it is still an operative treatment, so that it can only be used if an operation of repair or reconstruction is planned anyway. Before operative treatment of chronic complex instability, potential osseous abnormalities (varus morphotype) must be revealed; in case of uncertainty, an X-ray control is necessary.

Hip dislocations during sporting activities represent only 2%–5% of all hip dislocations. Most hip dislocations in sports can be categorised as “less complicated traumatic hip dislocations” by the Stewart-Milford classification due to the fact that minimal force is involved. The incidence of avascular necrosis of the femoral head greatly increases if the time to reduction is more than six hours. We report the case of a 38-year-old football player who suffered hip dislocation while kicking the ball with the medial aspect of the right foot in an external rotated manner of the right hip. Closed reduction was performed within 2 hours; postoperative follow-up was uneventful. Six months later the patient is out of any complaints; there is no sign of AVN of the femoral head.

In orthopedic surgery bony defects remains a challenge. In generally autologous or heterologous bony transplants can be used. Main problem is the limited amount of bone and donor site morbidity. Nowadays excellent implants and scaffolds at low costs are necessary in respect to the financial problems in our health care system and the strong financial limitations in clinical medicine. Recently a biomimetic approach, in which a porous synthetic bone substitute with properties similar to these of trabecular bone has been developed (VITOFOAM TM ). Aim of our study was to investigate whether cp-Ti or Ti6Al4V or stainless steel (316L) porous metal implants achieve material properties comparable to bone. Materials and MethodsThree cp-Ti, Ti6Al4Vand stainless steel (316L) porous metal specimen each with a pore size of 150 to 600 lm have been tested in respect to determine the Young's Modulus E (GPa), Compression Strength (MPa) and Porosity (%) under axial compression. ResultsYoung's Modulus of the cp-Ti samples was in the range of 1.2 to 2.8 GPa, for Ti6Al4V 2.3 to 4.1 GPa could be achieved. Compression Strength for cp-Ti and Ti6Al4V ranged from 30 to 65 MPa with porosity values ranged from 71 to 80 %. DiscussionThe highly porous nature of VITOFOAM TM combined with the good biocompatibility of cp-Ti or Ti6Al4V and the mechanical properties make these materials ideal bone scaffolds. Trabecular bone shows pore sizes of 300 -1500 lm, Young'