Resident duty-hour restrictions-who are we protecting?: AOA critical issues.

As advocated by Nasca, our teaching programs must nurture professionalism and the effacement of self interest that is the core of the practice of medicine and the profession. The evidence to date suggests that work-hour restrictions based solely on clock-defined time limits discourage, rather than promote, the professional behavior that we desire in tomorrow's physicians. Notwithstanding any issues related to duty hours or fitness for duty, a competency-based system of medical education is both desirable and necessary in the current environment of medical education. In the absence of evidence to suggest that duty-hour limits reduce medical errors and enhance patient safety, and until we have evolved to a competency-based system of resident education, a misguided and overzealous focus on limiting work hours should not be allowed to exert the unintended consequence of eroding the ethos of professionalism that we, and our patients, have come to expect of a physician.

Fractures of modern high nitrogen stainless steel cemented stems: cause, mechanism, and avoidance in 14 cases.

We present 14 cases of fracture of modern, high-nitrogen, stainless steel stems. Our clinical and radiological data suggest that heavy patients with small stems and poor proximal support are at risk for fracturing their implants. "Champagne-glass" canals can lead to the use of smaller stems often placed in varus, which can lead to cantilever bending and fatigue failure in the distal half of the stem. Metallurgical assessment of the retrieved high-nitrogen, stainless steel stems reveals microstructural inconsistencies that may contribute to their failure. Based on our findings, careful consideration and attention to technique is required when using stainless steel stems in patients with high body mass index or high weight. Technique is particularly important in femurs with champagne-glass canals.