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.     

Dietary intake of healthy subjects before and one year after dietary advice

This study was conducted to follow up healthy subjects from a previous study (Warwick & Williams, 1987) in which favourable dietary changes were achieved during 1 week immediately after dietary advice but were accompanied by reduced energy intakes and weight loss. Twenty-one subjects (8m, 13f; 57 per cent of the original group) participated in the follow-up study. Dietary intakes were measured using 7-d weighed records on three occasions: before, immediately after and 1 year after receiving dietary advice. Intakes 1 year after dietary advice continued to show some of the favourable changes observed immediately after the advice but were not accompanied by reduced energy intakes and weight loss. Intakes before, immediately after, and 1 year after dietary advice respectively were: energy, 9.0, 7.8 and 8.9 MJ/d (2150, 1860 and 2120 kcal/d); fat, 36.9, 32.9 and 31.5 per cent of total energy; carbohydrate, 44.2, 47.9 and 49.6 per cent of total energy; dietary fibre, 32, 36 and 36 g/d; sodium, 116, 97 and 110 mmol/d; and Na:K ratio, 1.4, 1.2 and 1.2 mmol. Nutrient densities for fibre and most micronutrients tended to be higher 1 year after dietary advice than before, but were highest immediately after the advice. Nutrient densities for sodium and total sugars did not vary between the 3 study weeks. It was concluded that our healthy subjects adapted their intakes to maintain energy balance while retaining favourable dietary changes for at least 1 year after dietary advice.