Der Einfluss des postoperativen femoralen offset auf die Funktion des Hüftgelenks nach trochantärer Femurfraktur und Versorgung mittels intramedullären Marknagels

Proximal femoral fractures are a very common injury in Europeans, especially in the elderly. Trochanteric fractures that were investigated in this study are the most common subtype of this group. Also, keeping the demographic changes in mind, the importance of the before mentioned fractures is going to increase drastically in the near future. Mostly these fractures are caused by trivial traumas. First choice therapy strategies include osteosynthetic procedures like dynamic hip screws (DHS) and intramedullary nailing. In contrary to the traditional assessment of a treatment’s success, which used to only consider postoperative mortality, the main focus of the evaluation of treatment results nowadays is on the most optimal and satisfying clinical outcome for the patient, which puts it now in the centre of modern research. Postoperative functionality of the hip joint was assessed by many studies and reviews evaluating the treatment of diseases of the hip using total hip arthroplasty. So far there has not been a comparable amount of studies investigating the effects of treating trochanteric femoral fractures with intramedullary nailing. As earlier findings in the field of total hip arthroplasty underlined the immense importance of a correct anatomical reconstruction of the operated area, this study was set up to proof and reassess those findings for an alternative operative strategy. The meaning of the femoral offset (FO) in total hip arthroplasty has been deeply investigated, which is why it was chosen to be the main parameter in this study. Hence 188 patients, who suffered either a peri, inter- or subtrochanteric fracture of the femur and were treated with intramedullary nailing, were radiologically analysed. Additionally the results were correlated with those of a clinical examination that was valuated during an earlier study (RePrOF). To account for hip rotation in the assessment of the FO on a.p.-radiographs, a mathematical method was chosen to allow for the rotation correction, to guarantee an optimal measurement of this radiological parameter. Looking at the results, an inverse correlation of the FO (rotation-corrected and relative FO alike) und both the primary and secondary outcome parameters Harris Hip Score (HHS) and Barthel-Index (BI) was found. In conclusion these findings suggest that a smaller FO is associated with an improved function of the hip joint. Surprisingly this is exactly the opposite of the results found in total hip arthroplasty researches, even though a more current study in this field of the year of 2014 discovered a similar relationship. So Liebs et al. described the association of a lower FO and a decreased pain level in patients treated with total hip arhroplasty, whereas a similar result concerning the function of the hip could not be found. It has to be taken into account that the results of this dissertation were statistically significant in the univariate analysis only. After consideration of possible confounders using a multivariate analysis this significance could not be confirmed. Thus the association of the FO with the postoperative function of the hip joint should be evaluated and proofed by further research. Only by more investigation a definite statement concerning the influence of the postoperative FO on the functional outcome after intramedullary nailing of trochanteric femoral fractures could possibly be made. Nevertheless does this dissertation show the trend that a smaller postoperative femoral offset may have a positive effect on the patient’s clinical outcome.