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The low profile of Less Invasive Stabilization System (LISS) plates allows them to be inserted between muscle and diaphysis with less bone exposure than that obtained with conventional plating techniques. In the unique LISS mechanism, unicortical screws thread into both plate and bone and allow the system to act as an internal fixator, with compressive pressure no longer bearing down on the periosteum. Results are minimal soft-tissue, periosteal, cortical, and vascular damage and no compromise in stability. This lesser degree of tissue disruption is hypothesized to accelerate bone healing, make bone grafting unnecessary, decrease infection rates, and prevent further injury by lessening overall surgical trauma. In a prospective, nonrandomized study conducted at a level I trauma center, we sought to determine the benefits of LISS plating in the treatment of distal femur fractures. Between January 1, 1998, and June 3, 2001, we treated 25 multiply injured adult patients admitted through the trauma department with 26 unstable distal femur fractures. Treatment involved minimally invasive plate osteosynthesis using LISS plating. Main outcome measures were time to union, postoperative complications, and functional impairment as measured with the SF-36v2 Health Survey. Results included no nonunions, no infections, no required bone grafting, and excellent range of motion and alignment.

To assess the agreement of clinical site and angiographic core laboratory readings obtained in the New Approaches to Coronary Intervention (NACI) registry, we reviewed the angiographic results obtained in 787 lesions assessed both by the sites and the core laboratory, including 135 lesions analyzed twice (> or =2 months apart) by the angiographic core laboratory. Although moderate agreement was demonstrated between the clinical site and angiographic core laboratory for qualitative lesion morphology such as lesion calcium (kappa [kappa] = 0.42), only fair agreement was found between site and core laboratory estimation of lesion ulceration (kappa = 0.33); thrombus (kappa = 0.30); and eccentricity (kappa = 0.27); with poor agreement for angulation (kappa = 0.16); and proximal vessel tortuosity (kappa = 0.03). Agreement for qualitative morphology was better for repeated core laboratory readings of lesion eccentricity (kappa = 0.75); angulation (kappa = 0.72); thrombus (kappa = 0.68); proximal vessel tortuosity (kappa = 0.66); and calcification (kappa = 0.64). Quantitative angiographic measurements correlated moderately between the clinical site using the digital caliper method and the core laboratory using the automated edge-detection method, including preprocedural percentage diameter stenosis (intraclass correlation [R] = 0.50) and postprocedural percentage diameter stenosis (R = 0.63). Repeated core laboratory readings had almost perfect agreement, with R ranging from 0.88 for postprocedural percentage diameter stenosis to 0.93 for reference vessel diameter and pre- and postprocedural minimal lumen diameters. Repeated angiographic core laboratory readings provided highly consistent quantitative and qualitative morphologic results in the NACI registry, but the core laboratory readings varied substantially from those obtained at the clinical site. More standardized angiographic analytic criteria and core laboratory feedback to investigators may improve agreement between the clinical sites and the angiographic core laboratory in subsequent studies.

Background: Plaque distribution (eccentricity) may be a determinant of the success of transcatheter therapy, and certain devices may be better suited to treating severely eccentric lesions than others. However, no study has compared methods for assessing plaque distribution or systematically studied the validity of the angiographic assessment of plaque distribution., Methods and Results: We studied 1446 native vessel target lesions in 1349 patients by intravascular ultrasound and coronary angiography. Angiographic and intravascular ultrasound criteria for lesion eccentricity were compared. Angiography showed that 795 of 1446 (55.0%) of target lesions were eccentric. When intravascular ultrasound was used, only 219 lesions (15.1%) had an arc of normal arterial wall within the lesion (equivalent to the pathological definition of lesion eccentricity). When an eccentricity index of >/= 3.0 was used, intravascular ultrasound classified 659 lesions (45.6%) as eccentric. The concordance rates of classification were only 47.7% (versus lesions containing an arc of normal arterial wall) and 53.8% (versus lesions with an ultrasound eccentricity index of >/= 3.0). More eccentric lesions had larger lumen cross-sectional areas, smaller plaque plus media and external elastic membrane cross-sectional areas, and smaller arcs of calcium, suggesting that they may represent less advanced atherosclerotic disease., Conclusions: There was significant discordance between angiography and ultrasound in assessing plaque distribution. Angiography appeared to detect lesion eccentricity more often than intravascular ultrasound. Furthermore, markedly eccentric lesions, in which there is an arc of normal vessel wall, were uncommon.