Skeletal fragility is a major complication of type 2 diabetes mellitus (T2D), but there is a poor understanding of mechanisms underlying T2D skeletal fragility. The increased fracture risk has been suggested to result from deteriorated bone microarchitecture or poor bone quality due to accumulation of advanced glycation end-products (AGEs). We conducted a clinical study to determine whether: 1) bone microarchitecture, AGEs, and bone biomechanical properties are altered in T2D bone, 2) bone AGEs are related to bone biomechanical properties, and 3) serum AGE levels reflect those in bone. To do so, we collected serum and proximal femur specimens from T2D (n = 20) and non-diabetic (n = 33) subjects undergoing total hip replacement surgery. A section from the femoral neck was imaged by microcomputed tomography (microCT), tested by cyclic reference point indentation, and quantified for AGE content. A trabecular core taken from the femoral head was imaged by microCT and subjected to uniaxial unconfined compression tests. T2D subjects had greater HbAc (+23%, p ≤ 0.0001), but no difference in cortical tissue mineral density, cortical porosity, or trabecular microarchitecture compared to non-diabetics. Cyclic reference point indentation revealed that creep indentation distance (+18%, p ≤ 0.05) and indentation distance increase (+20%, p ≤ 0.05) were greater in cortical bone from T2D than in non-diabetics, but no other indentation variables differed. Trabecular bone mechanical properties were similar in both groups, except for yield stress, which tended to be lower in T2D than in non-diabetics. Neither serum pentosidine nor serum total AGEs were different between groups. Cortical, but not trabecular, bone AGEs tended to be higher in T2D subjects (21%, p = 0.09). Serum AGEs and pentosidine were positively correlated with cortical and trabecular bone AGEs. Our study presents new data on biomechanical properties and AGEs in adults with T2D, which are needed to better understand mechanisms contributing to diabetic skeletal fragility.

Introduction The frequency of hip fractures, a major cause of morbidity and mortality for geriatric patients, is expected to increase exponentially in the next few decades. The aim of this study is to assess the ability of stainless-steel cannulated screws to reduce the risk of a femoral neck fracture, if placed prophylactically prior to a fall. Materials and Methods We created finite element models from computed tomography (CT) scan-based 3D models of a geriatric patient through 3D-image processing and model generation software. We used linear finite element simulations to analyze the effect of cannulated screws in the proximal femur in single-leg stance and lateral fall, which were processed for peak von Mises stresses and element failure. Findings Prophylactically placed cannulated screws significantly reduced failure in an osteoporotic proximal femur undergoing lateral fall. Three implanted screws in an inverted triangle formation decreased proximal femoral trabecular failure by 21% and cortical failure by 5%. This reduction in failure was achieved with a 55% decrease in femoral neck failure and 14% in lateral cortex failure. Conclusion Our results indicate that cannulated hip screws in an inverted triangle formation may strengthen an osteoporotic proximal femur in the event of a lateral fall. Mechanical testing on cadaveric or composite models is required to validate these results.

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Normal variants, radiographic artifacts, and unusual radiologic projections of normal structures may all be a cause of diagnostic confusion.We present one such unusual projection, which was noted on the carpal tunnel view of the wrist.