Posterior tibial tendoscopy: Description of an accessory proximal portal and assessment of tendon vascularization lesion according to portal

BackgroundPosterior tibial tendoscopy was codified in 1997 by Van Dijck, who described a portal between 1.5 and 2 cm proximally and distally to the tip of the medial malleolus. However, this approach does not allow proximal exploration of the posterior tibial tendon (PTT). We here describe an accessory portal 7 cm proximal to the medial malleolus, enabling complete PTT exploration.MethodsPosterior tibial tendoscopy was performed on 12 cadaver specimens, mapping PTT exploration and vascularization.ResultsThe accessory portal enabled the whole PTT to be explored, from the myotendinous junction to the entry into the retromalleolar groove. PTT observation quality was improved compared to using a submalleolar portal. Dissection confirmed systematic presence of a vincula on the posterior side of the tendon, connected to the flexor digitorum longus (FDL) tendon, containing collateral vessels of the posterior tibial artery. None of these elements were damaged by the tendoscopy as long and the scope and motorized instruments were not rotated on the posterior side of the supramalleolar part of the PTT.ConclusionsThis accessory entry portal provides complete PTT exploration without the risk of neurovascular bundle lesion.     

Calcium inhibits promotion by hot dog of 1,2‐dimethylhydrazine‐induced mucin‐depleted foci in rat colon

Epidemiology suggests that processed meat is associated with colorectal cancer risk, but few experimental studies support this association. We have shown that a model of cured meat made in a pilot workshop promotes preneoplastic lesions, mucin‐depleted foci (MDF) in the colon of rats. This study had two aims: to check if real store‐bought processed meats also promote MDF, and to test if calcium carbonate, which suppresses heme‐induced promotion, can suppress promotion by processed meat. A 14‐day study was done to test the effect of nine purchased cured meats on fecal and urinary biomarkers associated with heme‐induced carcinogenesis promotion. Fecal water from rats given hot dog or fermented raw dry sausage was particularly cytotoxic. These two cured meats were thus given to rats pretreated with 1,2‐dimethylhydrazine, to evaluate their effect on colorectal carcinogenesis. After a 100‐days feeding period, fecal apparent total N‐nitroso compounds (ATNC) were assayed and colons were scored for MDF. Hot dog diet increased fecal ATNC and the number of MDF per colon compared with the no‐meat control diet (3.0 ± 1.7 vs. 1.2 ± 1.4, p < 0.05). In a third study, addition of calcium carbonate (150 µmol/g) to the hot dog diet decreased the number of MDF/colon and fecal ATNC compared with the hot dog diet without calcium carbonate (1.2 ± 1.1 vs. 2.3 ± 1.4, respectively, p < 0.05). This is the first experimental evidence that a widely consumed processed meat promotes colon carcinogenesis in rats. It also shows that dietary prevention of this detrimental effect is possible.