Patellofemoral joint arthroplasty: patient selection,surgical technique and outcomes

Isolated patellofemoral arthritis is an increasingly recognized entity, and is usually associated with previous patellofemoral dysplasia or instability. Patellofemoral arthroplasty (PFA) has evolved significantly in recent years, both in terms of implant design and importantly in the understanding of appropriate patient selection. This review outlines the indications and investigations for PFA, provides a brief history of the development of contemporary implants, and presents the clinical outcomes for the prostheses most commonly used in the UK. In addition, it provides a detailed surgical technique for implantation of an onlay implant, with tips on how to optimize patellofemoral biomechanics and thus achieve a consistently good outcome.     

The politics of interprofessional working and the struggle for professional autonomy in nursing

This study of interprofessional work relations in a Canadian mental health team examines how nursing deployed different forms of power in order to alter the mental health division of labour, to gain administrative, organizational and content control over its own work, expand its jurisdictional boundaries by expropriating the work of other professionals, and exclude others from encroaching on its old and newly acquired jurisdictions. This is set against the context of nursing's long-standing professional project to consolidate and expand its professional jurisdiction. Using an ethnographic study of a single interprofessional mental health team in a psychiatric hospital in Canada, the paper attempts to understand the politics and paradoxes involved in realizing nursing's professional project and how the politics of professional autonomy and professional dominance are actually conducted through micro-political struggles. The data demonstrates the effects of the political struggles at the organizational and work process levels, particularly in the forms of collaboration that result. Nurses gained substantial autonomy from medical domination and secured practical dominion over the work of non-medical professionals. New forms of interprofessional collaboration were accomplished through both simultaneous and sequential micro-political struggles with psychiatrists and non-medical professionals, and the formation of political alliances and informal agreements. Nursing solidarity at the elite level and substantial effort by the elite nurses and their committed colleagues to mobilize their less enthused members were fundamental to their success. The nurses deployed political (power) strategies and tactics to organize and reorganize themselves and other professionals on multiple levels (politically, organizationally, ideologically, socially and culturally). This study reveals the complexity and robustness of micro-political dynamics in the constitution of professional and collaborative interprofessional work relations.     

Carnitine, valproate, and toxicity

Carnitine is an important nutrient that is present in the diet (particularly in meat and dairy products) and is synthesized from dietary amino acids. It functions to assist long-chain fatty acid metabolism and to regulate the ratio of free coenzyme A to acylcoenzyme A in the mitochondrion. Carnitine deficiency occurs in primary inborn errors of metabolism, in nutritional deficiency, and in various other disorders including antiepileptic drug therapy. Valproate therapy is often associated with decreased carnitine levels and occasionally with true carnitine deficiency. Some experimental and clinical evidence links valproate-induced carnitine deficiency with hepatotoxicity, but this evidence is limited and inconclusive. Carnitine supplementation has been useful in some studies, but these data are also limited. Young children with neurologic disabilities taking multiple antiepileptic drugs may have the greatest risk for carnitine deficiency. Measurement of carnitine levels appears warranted in these patients and in patients with symptoms and signs of possible carnitine deficiency.