Sults in increasing load share of the implant and therefore higher stress within the implant. We also investigated the relationship of interfragmentary movement to the fracture stability. A finite element model was developed for a cephalomedullary nail within a synthetic femur and simulated a pertrochanteric fracture, a lateral neck fracture, and a subtrochanteric fracture. The femur was loaded with a hip force and was constrained physiologically. The FE model was validated by mechanical experiments. All three fractures resulted in similar values for stiffness (462–528 N/mm). The subtrochanteric fracture resulted in the highest local stress (665 MPa), and the pertrochanteric fracture resulted in a lower stress (621 MPa) with even lower values for the lateral neck fracture (480 MPa). Thus, intramedullary implants can stabilize unstable hip fractures with almost the same amount of stiffness as seen in stable fractures, but they have to bear a higher load share, resulting in higher stresses in the implant....

After septic failure of total knee arthroplasty (TKA) and multiple revision operations resulting in impaired function, bone and/or soft-tissue damage a reconstruction with a revision arthroplasty might be impossible. Salvage procedures to regain mobility and quality of life are an above-the-knee amputation or knee arthrodesis. The decision process for the patient and surgeon is difficult and data comparing arthrodesis versus amputation in terms of function and quality of life are scarce. The purpose of this study was to analyse and compare the specific complications, functional outcome and quality of life of above-the-knee amputation (AKA) and modular knee-arthrodesis (MKA) after septic failure of total knee arthroplasty. Eighty-one patients treated with MKA and 32 patients treated with AKA after septic failure of TKA between 2003 and 2012 were included in this cohort study. Demographic data, comorbidities, pathogens and complications such as re-infection, implant-failure or revision surgeries were recorded in 55MKA and 20AKA patients. Functional outcome with use of the Lower-Extremity-Functional-Score (LEFS) and the patients reported general health status (SF-12-questionnaire) was recorded after a mean interval of 55 months. A major complication occurred in more than one-third of the cases after MKA and AKA, whereas recurrence of infection was with 22% after MKA and 35% after AKA the most common complication. Patients with AKA and MKA showed a comparable functional outcome with a mean LEFS score of 37 and 28 respectively (p = 0.181). Correspondingly, a comparable physical quality of life with a mean physical SF-12 of 36 for AKA patients and a mean score of 30 for MKA patients was observed (p = 0.080). Notably, ten AKA patients that could be fitted with a microprocessor-controlled-knee-joint demonstrated with a mean LEFS of 56 a significantly better functional outcome than other amputee patients (p < 0.01) or MKA patients (p < 0.01). Naturally, the decision process for the treatment of desolate situations of septic failures following revision knee arthroplasty is depending on various factors. Nevertheless, the amputation should be considered as an option in patients with a good physical and mental condition.

The aim of this study was to evaluate a standardized method of treatment of femoral nonunion of the isthmal femur excluding non-united metaphyseal fractures. Between 2003 and 2010, 72 consecutive patients with nonunion of the femoral shaft were operated using a standardized protocol in our trauma department and followed up for successful union and functional result. Osseous healing was observed in 71 patients (98%). Only one patient was lacking bone healing following a time period of 24 months after the first exchange nailing and 5 months after the second exchange nailing. In 59 patients (82%), uneventful and timely bone healing after exchange nailing was detected. In 18% of patients (n = 13), delayed bone healing was observed and required additional therapy. In the majority of patients (61%), bone healing occurred within the first 2 to 5 months, only 18% of patients' duration of bone healing exceeded 8 months. In 62 patients (86%), no relevant or clinically apparent leg-length discrepancy prior to and after exchange nailing was detected as well as no significant axis deviation or malrotation. Functional studies including simple clinical gait and standing analysis, return to activities of daily life, return to sports activities, and return to work were all reached on a satisfying level. Reamed intramedullary exchange nailing as described in this study is the treatment of choice for aseptic femoral shaft nonunion with a high rate of bone healing and a low rate of complications including length discrepancy or malrotation and a good functional outcome.