Hallux Pronation in Hallux Valgus: Experimental and Radiographic Study.

Toe pronation is a frequent sign in hallux valgus (HV), but it is difficult to assess and quantify. The aim of this study was to evaluate the relation between big toe pronation with both radiological and clinical findings and to determine if toe pronation is an influential factor in severity of HV. Six big toe donor proximal phalanges were used to create a radiographic calibrating system controlling their pronation at 0° to 60°. A linear regression model was used to predict proximal phalanx pronation in radiographs. Big toe pronation in HV was clinically evaluated with a prospective study using 132 patients from our surgical waiting list and a control group of 30 patients without HV. Patients standing barefoot on a rigid platform were used to obtain the nail-floor angle. We obtained the following angles: HV, intermetatarsal, interphalangeal, distal articular set angle, proximal articular set angle, first metatarsal pronation, proximal phalanx pronation, and sesamoid bones displacement. We obtained an equation to predict proximal phalanx pronation according to the proportion of the rotated phalanx (p < .001, r = 0.98), and used an intraclass reliability test to assess the intra-/interobserver reliability (p < .001, intraclass correlation [ICC] = 0.89/p < .001, ICC = 0.82). We found that the relation between HV severity and proximal phalanx pronation, nail-floor angle, and first metatarsal pronation was statistically significant (p < .0001, r = 0.64). Proximal phalanx pronation and nail-floor angle should be considered to classify the severity of HV. Using a mathematical formula, we can predict proximal phalanx pronation on radiographs. Clinical Level of Evidence.

In vivo bactericidal efficacy of farnesol on Ti6Al4V implants. / Eficacia bactericida in vivo del farnesol sobre implantes de Ti6Al4V.

OBJECTIVE: To evaluate the in vivo anti-staphylococcal bactericidal activity of farnesol on Ti6Al4V surfaces. MATERIAL AND METHODS: An experimental model of infection in biomaterials was developed by inoculation of Staphylococcus aureus ATCC 29213 into the canal of both femurs of 15 Wistar rats. A Ti6Al4V pin impregnated with 30mM of farnesol was inserted into study femur, and a Ti6Al4V control was inserted into the control femur. To evaluate the bactericidal efficacy, a comparison was made between the median of the colony forming units recovered after inoculation in the study group and the control group for different times of euthanasia and inoculum size. RESULTS: The median expressed as Log10 CFU counts obtained with farnesol titanium pin was 4.26, and in control group, it was 4.86, which was statistically significant (P=.001) on applying the Student t test for related samples. The median reduction obtained in farnesol pins relative to the control was 74%. CONCLUSIONS: Treatment with farnesol 30mM on Ti6Al4V pins appears to decrease the rate of colonisation by Staphylococcus aureus.