Abstract
Undisplaced or minimal displaced medial neck femoral fractures are treated with canulated screws either in young or in elderly patients with good functional capacity, without severe comorbidity and cognitive impairment. We also perform this procedure in patients with very low daily activities and affected by severe comorbidity, with the aim to reduce pain. We reserve total hip replacement in middle-advanced age, with good level of functional activity and adequate bone-stock. We use bipolar hemiarthroplasty in patients that need early mobilization for the presence of comorbidities that could worsen. We prefer cemented bipolar hemiarthroplasty, as it gives an optimal primary stability, without press-fit. We prefer to utilize bipolar hemiarthroplasty with memory shape stem F.G.L. (Fig.1) in high risk patients (ASA classification). In fact the use of cement prolongs duration of surgery and is associated with higher perioperative mortality from cardiopulmonary complications. This stem in its metaphyseal region has 10 tabs, made of a Nitinol alloy (Ni-Ti). The feature of this alloy is to enlarge when brought to a certain temperature. When F.G.L. stem is mantained at 4° - 7° C the Nitinol (r) tabs are in the “restrained” configuration. Just at the time of surgery procedure, the stem is taken out of the refrigerator and inserted into the femoral diaphysis. At corporeal temperature, the Nitinol tabs enlarge, compressing the metaphyseal cancellous femoral region and give an immediate primary stability. We report clinical and radiological results of 15 patients (mean follow-up: 8 months) that underwent surgical procedure of bipolar hemiarthroplasty with F.G.L. stem in our department from March 2008 to December 2009. We had no perioperative complications and the results overlapped those of patients that underwent standard cemented bipolar hemiarthroplasty. The advantage of the use of F.G.L. stem is that it allows an immediate primary stability without searching an extreme press-fit. The disadvantage is the higher cost respect a standard cemented bipolar hemiarthroplasty. Therefore its use should be limited to those patients in which the surgery time must be contained for severe comorbidity, or in patients in which specific cardio-pulmonary complaints make dangerous the use of cement.
