Tuberosity-overlapping Fixation of the Humeral Shaft in Humeral Head Replacement Surgery

The fixation technique of bony fragments is crucial for the bone union of the tuberosities after humeral head replacement (HHR) for a comminuted fracture of the proximal humerus. To increase the bone union rate, we reduce tuberosities to overlap on the humeral shaft by approx. 1 cm and fix them with cable wire. Herein, we retrospectively investigated the clinical and radiographic outcomes of our procedure. Twenty-six patients who underwent cementless HHR for the treatment of comminuted fractures of the proximal humerus were investigated. The Constant-Murley score, active shoulder mobility, and bone union rate were evaluated. The mean duration of follow-up was 56.3 months (range 24-197). At the final follow-up, the average Constant-Murley score was 58 (range 40-76). Forward elevation was 126° on average (range 35°-180°). Twenty-three cases (88%) showed bone union between the tuberosities and the shaft at an average follow-up of 4.1 months (range 4-5 months) after surgery. Non-union was noted in 1 case, and bone resorption was noted in 2 cases. The bone union rate and the clinical outcome of our procedure were relatively favorabl

Pharmacokinetic modeling of multislice dynamic contrast-enhanced MRI in normal-healing radial fractures:A pilot study

PURPOSE: To define the range of quantitative pharmacokinetic parameters in normal-healing bone with dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI). DCE-MRI is an established technique for characterizing abnormal tissue microvasculature within solid tumors, but has also shown promise for assessing bone and bone marrow.   MATERIALS AND METHODS: In this study ethical approval for eight patients was obtained. Inclusion criteria were an extra-articular distal radial fracture in patients aged 20-50 years which had united by 6 weeks in plaster cast. This was assessed by an experienced orthopedic surgeon. DCE-MRI was performed at 1.5T 6 weeks after initial injury. The transfer constant (K(trans) ), transfer rate (Kep ), and initial area under the curve (IAUC) values for the fracture site and adjacent marrow were obtained for each patient.   RESULTS: The mean T1 , K(trans) , Kep , and IAUC at the fracture site were 1713 (standard deviation [SD] 645), 0.09 (SD 0.07), 0.17 (SD 0.17) and 4.9 (SD 4.4). The relative standard deviation (RSD) for the fracture site ranged from 0.38 to 0.97 and for the adjacent marrow ranged from 0.95-3.88. Within each patient the range of RSDs was 0.04-0.42 for T1 , 0.26-0.91 for K(trans) , 0.14-1.06 for Kep , and 0.35-0.96 for the IAUC.   CONCLUSION: Pharmacokinetic measures of perfusion can be obtained from healing fractures using DCE-MRI with "excellent" intraclass correlation coefficients for inter- and intrarater reliability. The use of these perfusion parameters is limited by wide patient-to-patient variation and slice-to-slice variation within patients. J. Magn. Reson. Imaging 2015