ä Oxidative stress has been implicated as a causative factor in many disease states, possibly including the diminished bone mineral density in osteoporosis.ä Understanding the effects of oxidative stress on the development of osteoporosis may lead to further research improving preventative and therapeutic measures that can combat this important contributor to morbidity and mortality worldwide.ä A diet rich in whole plant foods with high antioxidant content along with antioxidant-preserving lifestyle changes may improve bone mineral density and reduce the risk of fragility-related fractures. While it is not explicitly clear if antioxidant activity is the effector of this change, the current evidence supports this possibility.ä Supplementation with isolated antioxidants may also provide some osteoprotective benefits, but whole plant foodderived antioxidants potentially have more overall benefits. Larger-scale clinical trials are needed to give credence to definitive clinical recommendations.

No abstract

No abstract

Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Periprosthetic fractures around total knee arthroplasty have become an increasingly common and challenging orthopaedic problem. Appropriate management of these fractures depends on careful scrutiny of radiographs and a thorough clinical history to exclude the diagnosis of a periprosthetic infection. In a periprosthetic tibial fracture with a stable, well-aligned tibial component and well-aligned mechanical tibial axis, the fracture can be successfully managed with closed reduction and cast immobilization; meticulous follow-up is essential to ensure that the alignment is maintained. Major fracture displacement, tibial component instability, and tibial component malalignment are all indications for surgical intervention. The ideal surgical intervention depends on the fracture characteristics and the stability and alignment of the tibial component.

Objectives: The purpose of this study was to compare the static and dynamic mechanical properties of a modified crossed cannulated screw configuration (CS), the inverted triangle cannulated screw configuration (IT) and a compression hip screw with derotation screw (CHS) in Pauwels Type III femoral neck fractures. Methods: Thirty synthetic femora were divided into three groups and vertical femoral neck osteotomies were made. Ten osteotomized femora were fixed with a modified cross screw (CS) configuration, ten were fixed with three parallel screws in an inverted triangle (IT) configuration, and the remaining ten osteotomized femora were fixed with a compression hip screw (CHS) construct. All groups were tested using a cyclic (up to 15,000 load cycles) axial loading protocol and survivors were statically loaded to failure. Cycles to failure, load to failure and stiffness were calculated. The Kaplan-Meier method was used to estimate survival functions and were compared among fixation methods. The relationship between construct structural properties (maximum load and stiffness) and treatment were assessed using general linear modeling. Results: All CHS fixation constructs survived the 15,000 cycle loading protocol. They endured longer (p = 0.034) than the CS fixation constructs (mean failure 13,332 cycles), but were not different from IT fixation constructs (mean failure 13,592 cycles). Maximum loads to failure for CS (3,870 N) and IT (3,756 N) fixation constructs were not different, but were less (p<0.0001) than the maximum loads to failure for the CHS fixation constructs (5,654 N). These findings parallel the results of the axial stiffness measurements: CS fixation constructs (663.01 N/mm) were not stiffer than IT fixation constructs (620.0 N/mm), but were less (p=0.0005) than the axial stiffness of the CHS fixation constructs (1,241.86 N/mm). Conclusions: The biomechanical performance of the compression hip screw (CHS) fixation method was superior to both the modified cross screw (CS) fixation method and the inverted triangle (IT) fixation method using a synthetic femoral model and this test protocol. Biomechanical performance of the latter two groups was indistinguishable. We recommend the use of CHS with derotational screw construct for Pauwels III femoral neck fractures whenever possible.

Prognostic Level I. See Instructions for Authors for a complete description of levels of evidence.

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.