Introduction. The Z or “scarf” osteotomy was first described by Meyer in 1926 and then by Burutaran in 1976. It was later popularised by Weil in the USA and Barouk in Europe in the 1990's and is now an accepted technique that forms part of a surgeons' armamentarium. The theory of Diffusion of Innovations was described by Rogers in 1962 to explain how novel ideas are accepted into practice across different industries, including medicine. It has never previously been used to study the adoption of ideas in foot and ankle surgery. Methods. This paper uses publication volume as a surrogate marker for adoption, as described previously by the authors. Briefly, a systematic review of the literature was carried out. MESH headings included ‘Hallux Valgus’, and ‘osteotomy’ or ‘SCARF’ or ‘Z osteotomy’ or ‘bunionectomy’. 2818 publications were identified and the abstracts were reviewed excluding 2699 publications for non-relevance. The data was analysed by year of publication, country of origin, as well as for level of evidence. Results. There were 120 publications relating to SCARF osteotomy, which when plotted on a graph produced an s shaped curve. 58% of publications came from Europe and 38% from the USA. There was only a single level 1 paper published in 2008. Discussion. This study confirms that publication volume is a surrogate marker for adoption and that SCARF osteotomy became adopted by the late 2000's as indicated by the plateau on an s-shaped curve. Post market surveillance has led to a further rise in recent publications indicating that certain issues still need resolving before the laggards adopt this technique. Despite SCARF having been around for more than 80 years, very little high level evidence has been published of its effectiveness. Recommendations are made as to how future innovations should be introduced in foot and ankle surgery

Objectives. Inflammation of the retrocalcaneal bursa (RB) is a common clinical problem, particularly in professional athletes. RB inflammation is often treated with corticosteroid injections however a number of reports suggest an increased risk of Achilles tendon (AT) rupture. The aim of this cadaveric study was to describe the anatomical connections of the RB and to investigate whether it is possible for fluid to move from the RB into AT tissue. Methods. A total of 20 fresh-frozen AT specimens were used. In ten specimens, ink was injected into the RB. The remaining ten specimens were split into two groups to be injected with radiological contrast medium into the RB either with or without ultrasonography guidance (USG). Results. In specimens injected with ink, diffusion outside the RB was observed with staining of the anterior portion of the AT. In eight contrast-injected specimens (five USG, three non-USG), a similar localised diffusion pattern was observed, with the contrast identified superiorly and anteriorly. In two contrast-injected specimens (non-USG), the diffusion pattern was more extensive. Conclusion. This study confirmed the existence of connections between the RB and the AT, especially rich in the anteroinferior portion of the tendon, which should be considered a weak zone for substances injected into the RB. We hypothesise that this part of the AT might be most vulnerable to rupture after corticosteroid injections. Cite this article: P. A. Pękala, B. M. Henry, J. R. Pękala, K. Piska, K. A. Tomaszewski. The Achilles tendon and the retrocalcaneal bursa: An anatomical and radiological study. Bone Joint Res 2017;6:446–451. DOI:10.1302/2046-3758.67.BJR-2016-0340.R1