RESUMEN
PURPOSE: Does the cylindrical shaped bone block allow a stable construct for the arthrodesis of the pubic symphysis compared to a rectangular shaped bone block. The cylindrical shaped bone block stabilized by a 3.5 symphyseal plate is inferior to the stabilization with an internal fixator. METHODS: This study analyzed the arthrodesis of the pubic symphysis on 24 synthetic pelvises, using a rectangular shaped bone block (control group) or a cylindrical shaped bone block, stabilized with a symphysis locking plate (n = 8) as the standard clinical procedure. Additionally we analyzed the stability using an internal fixator. RESULTS: This study showed that utilizing a cylindrical shaped synthetic bone graft results in a significant higher contact area and compression force compared to the classical rectangular shaped graft. Furthermore, the stabilization with an internal fixator had the tendency for increases of compression force and contact area, yet without a statistical significance, when compared to the plate fixation. CONCLUSION: The novel method of cylindrical symphysis resection and cylindrical bone block implantation allowed an increased biomechanical stability compared to using a classical rectangular bone graft, also resulting in higher contact area. Moreover, this technique would also allow a minimally invasive approach for this purpose, which in turn could preserve perisymphyseal ligaments, thereby improving healing in a clinical context.
RESUMEN
Proximal femur fractures account for increased healthcare costs whenever patients are unable to return to their previous state of residence. Studies suggest that patients benefit from early weight-bearing, yet compliance to weight-bearing regimes is poorly investigated. Aim of the study was thus to show the clinical feasibility of a new measurement tool able to determine continuous weight-bearing behavior after intramedullary nail osteosynthesis of intertrochanteric femur fractures, assess the influence of weight-bearing on clinical outcome and determine rehabilitation demand based on early postoperative gait performance. In an observational study, gait data of 22 patients with intertrochanteric femur fractures were evaluated. During the inpatient stay patients were continuously monitored with a gait analysis insole. Primary outcome was the amount of weight-bearing reached. Short-term functional outcome, as well as return to the previous state of living were evaluated in relation to weight-bearing and activity during the inpatient stay. With the presented technique continuous gait data of all patients during postoperative mobilization could be obtained. Only 13 patients reached full weight-bearing. The technique was feasible to determine correlations between weight-bearing and outcome, as well as between gait activity and outcome. Significant gait differences between patients able to return to their previous state of living and those who could not were seen. Dynamic insole measurements are feasible to continuously determine the postoperative gait performance. Their postoperative use showed, that the continuous compliance to permissive weight-bearing after intertrochanteric fractures is low. The presented measurement technique has the potential to identify patients at risk for reduced outcome and impending loss of previous residence status. Further studies will have to investigate the effects of technology assisted "patient at risk" identification and adapted therapy on clinical outcome.