A biomechanical study on fixation stability with twin hook or lag screw in artificial cancellous bone

The twin hook has been developed as an alternative to the conventional lag screw to be combined with a barrelled side-plate in the treatment of trochanteric hip fractures. With two oppositely directed apical hooks introduced into the subchondral bone of the femoral head, the twin hook provides different stabilising properties to the lag screw. The femoral head purchase of the twin hook and the lag screw were compared in a biomechanical study using artificial cancellous bone, and responses to axial and torsional loading was determined. A distinct yield point in load and torque was noted for the lag screw, representing failure of the laminas supporting the threads. For the twin hook, gradual increase of load and torque occurred during impaction of the bone supporting the hooks. The peak loads and torques were higher for the lag screw, but were similar for both devices after 8 rum deformation. The stiffness was higher for the lag screw, but in counter-clockwise rotation the stiffness for the lag screw was negligible. The twin hook appeared to provide fixation stability comparable to that offered by the lag screw, but with conceivable advantages in terms of a deformation response involving bone impaction and gradually increasing stability

The Hansson Twin Hook is adequate for fixation of trochanteric fractures - 2 fixation failures in a series of 157 prospectively followed patients

Background and purpose The Hansson Twin Hook (HTH) is an alternative to the lag screw in the treatment of trochanteric fractures. In osteoporotic bone, mechanical tests have indicated that the HTH has better fixation properties than the lag screw. We evaluated the fixation stability of the HTH in a large series of elderly patients with trochanteric fractures. Many surgeons were involved in assessment of whether the device was user-friendly. Patients and methods In a prospective bicentric study, 55 surgeons used the HTH and a standard plate in 157 consecutive patients with trochanteric fractures, 83% of which were unstable. The mean age of the patients was 83 (43-98) years. They were followed regularly clinically and radiographically for at least 4 months, with a radiographic file search at 2 years. Results Technical errors occurred intraoperatively in 7 cases. The reduction of the fracture was inaccurate in these patients; thus, the HTH had not been placed centrally in the femoral head. One of these errors was immediately and easily corrected without interference with the standard plate, and caused no further problems. 2 of the remaining 6 intraoperative errors developed into failures of fixation during the 2- year period. Interpretation The HTH gives adequate fixation in the bone of elderly patients with trochanteric fractures and has a low failure rate. It is also easy to use

Long-term cost and effect on quality of life of osteoporosis-related fractures in Sweden

Background and purpose Few economic or quality-of-life studies have investigated the long-term consequences of fragility fractures. This prospective observational data collection study assessed the cost and quality of life related to hip, vertebral, and wrist fracture 13-18 months after the fracture, based on 684 patients surviving 18 months after fracture. Patients and methods Data regarding resource use and quality of life related to fractures was collected using questionnaires at 7 research centers in Sweden. Information was collected using patient records, register sources, and by asking the patient. Quality of life was estimated using the EQ-5D questionnaire. Direct and indirect costs were estimated from a societal standpoint. Results The mean fracture-related cost 13-18 months after a hip, vertebral, or wrist fracture were estimated to be (sic)2,422, (sic)3,628, and (sic)316, respectively. Between 12 and 18 months after hip, vertebral, and wrist fracture, utility increased by 0.03, 0.05, and 0.02, respectively. Compared to prefracture levels, the mean loss in quality of life between 13 and 18 months after fracture was estimated to be 0.05, 0.11, and 0.005 for hip, vertebral, and wrist fracture. Interpretation The sample of vertebral fracture patients was fairly small and included a high proportion of fractures leading to hospitalization, but the results indicate higher long-term costs and greater loss in quality of life related to vertebral fracture than previously believed

Extramedullary fixation of 569 unstable intertrochanteric fractures: a randomized multicenter trial of the Medoff sliding plate versus three other screw-plate systems

We compared the efficacy of the Medoff sliding plate (MSP) with 3 other screw-plate systems for fixation of unstable intertrochanteric fractures in a randomized multicenter trial of 569 elderly patients. The MSP has biaxial dynamic capacity along both the neck and the shaft of the femur unlike the other systems, which lack dynamic capacity along the shaft. 268 fractures were operated on with the MSP, and 301 with the dynamic hip screw (DHS), with or without a trochanteric stabilizing plate (DHS/TSP) or with the dynamic condylar screw (DCS). The MSP had recently been shown to the surgeons.The patients in the groups were similar as regards age, domestic situation, preinjury walking ability and type of fracture. We followed the patients clinically and radiographically for at least 1 year. There was no significant difference in walking ability at follow-up or rate of return to home. Fixation failure occurred in 18/268 fractures operated on with the MSP, in 8/238 with the DHS, in 3/49 with the DHS/TSP and in 1/14 with the DCS. The difference in the rate of fixation failure was not statistically significant when the MSP group was compared to the 3 other groups. In 14 of the 18 fixation failures in the MSP group, the biaxial dynamic capacity of the MSP had not been used due to technical errors by surgeons, unfamiliar with the new method. No selection bias was found regarding fracture types in the 2 subgroups of patients with correct or inadequate biaxial dynamization. Extramedullary fixation of unstable intertrochanteric fractures with these implants showed a low failure rate. When using the MSP, biaxial dynamization must be correctly performed