Search

ust like today, the late medieval period knew many challenges caused by climate change and diseases. The Little Ice Age, starting in the fourteenth century, and the famines and diseases that followed left their marks on past European populations, which are still visible today in the human skeletal remains. The influences of these potential stressors on human skeletons from the late medieval population from Ypres, Belgium, is assessed via stable isotope and osteological analyses. Ypres, rapidly growing into one of the biggest cities in Europe during the thirteenth century, was struck by social polarisation, conflicts, proletarianization, and famines. As a result, the booming city once known for its cloth industry, started to decline during the fourteenth century and provides a good opportunity to study the dynamics of densely populated urban centers during such tumultuous times. Preliminary results from the stable carbon and nitrogen isotopes (δ13C & δ15N) analyses seem to indicate some levels of physiological of stress with higher δ13C & δ15N values observed in some of the individual’s ribs compared to the femurs, suggesting they may have suffered from malnutrition or even starvation. The stable isotope results occasionally match pathological changes. One individual in particular displayed enamel hypoplasia, cribra orbitalia, and vitamin D deficiency and had high δ15N values in the ribs (14.1‰), reinforcing the possibility that inhabitants of Ypres suffered from starvation. This presentation provides more insights into how bioarchaeology can help research the health status in Ypres during its rise and decline in the late medieval period.

Oxygen isotopes in biological apatite are commonly used as a proxy in mobility studies to identify ‘locals’ vs. ‘non-locals’ and, as a further step, to possibly identify compatible regions for those individuals that are characterized as ‘non-locals’. However, factors like temperature, warmer vs. colder climatic phases, air pressure, altitude, cooking practices..., affect δ18O values rendering interpretations difficult. Different methods to identify outliers within a population have been proposed and include 3*MAD or Turkey IQR, and most studies primarily base their ‘non-local’ oxygen interpretations on the offsets with expectations compared to oxygen isotope maps. However, recent oxygen results from Belgium highlight potential issues using these maps. Oxygen isotope results measured on tooth enamel carbonates from different Flemish cemeteries (Koksijde, and Ypres) ranging from the early till late medieval period are inconsistent with the existing oxygen isotope maps. Ranging up to -3.4 ‰ (VPDB), the δ18O values observed in these 2 sites are among the highest in Europe. The exact reason for these differences with the rest of north-western Europe *remain unclear. We argue that methodological issues can be ruled out as the results from samples from other locations in Europe, prepared with the same pre-treatment and measured in the same lab during the same runs, are compatible with the oxygen isotope maps. Further research is needed to understand the reasons for the large difference in oxygen isotope ratios between Belgian populations and the rest of Europe. The implications of these findings could significantly impact mobility studies within Europe and their interpretations.

A-0412 Ultrasonographic evaluation of theflexor tendons in function of volar platepositioning and pronator quadratus repairon cadaveric modelsChul Ki Goorens1,2, Kjell Van Royen2, Stephane Grysseels2,Steven Provyn 3, Johan De Mey2, Thierry Scheerlinck2,Jean Goubau2(1) Regionaal Ziekenhuis Tienen, Tienen, Belgium(2) University Hospital Brussels, Brussels, Belgium(3) Vrije Universiteit Brussel, Brussels, BelgiumFlexor tendon injury is a potential complication aftervolar plating of distal radius fracture due to the frictionof the flexor tendons and the prominence of thevolar plate. The flexor pollicis longus (FPL) tendon ismost at risk.To assess the risk of flexor tendon injury, we evaluatedwith ultrasonography in 17 cadaveric hands(12 males and 5 females; mean age 77.1 years withrange of 45–94 years) the distance between the FPLand the most volar prominence. If direct frictionbetween the FPL and the prominence occured, possiblebulging of the FPL tendon over the prominencewas also measured. This assessment was performedwith and without the pronator quadratus (PQ) musclesectioned. This was repeated with a volar plate (volarplate 2.4 double column plate; Synthes) fixed proximalto the watershed line, with a volar plate fixed distalto the watershed line, and an LCP volar rim distal radius plate (Synthes) and a low-profile volar hookplate contouring the volar rim. Statistic analysis wasperformed with paired t test (p < 0.05).Mean distance from the FPL to the volar prominence(volar rim) decreased statistically significantly whenPQ was sectioned (0.3 mm) versus an intact PQ (1.5mm). Besides, mean distance also decreased statisticallysignificantly when a volar plate was fixed,even proximal to the watershed line with an intactPQ (0.4 mm) compared to no plate placed. Mean distancedecreased statistically significantly when thevolar plate was placed distal to the watershed line(−0.2 mm) versus proximal to the watershed line.Frequently (53%) bulging of the FPL over the prominenceof the plate occurred when volar plate wasplaced distal to the watershed line. When volar platewas placed proximal to the watershed line, mean distancealso decreased statistically significantly whenthe PQ was sectioned (0.1 mm) vs an intact PQ. Identicalresult was obtained when volar plate was placeddistal to the watershed line, since mean distance alsostatistically significantly decreased when the PQ wassectioned (−0.5 mm) versus an intact PQ. FPL bulgingincidence increased to 76%. Finally, mean distancedid not differ statistically significantly (p > 0.05) whenvolar rim plate was fixed contouring the volar rim(−0.1 mm range 0) versus a plate distal to the watershedline, although statistically significant increasewas measured when volar rim plate was placed withPQ repaired versus sectioned (−0.4 mm).Ultrasonography is a possible technique to evaluatepossible friction between the flexor tendons andthe volar plate prominence. Our results suggest theimportance of correct positioning of the volar plateproximal to the watershed line and the repairing of thepronator quadratus to increase the distance from theflexor pollicis longus tendon to the volar prominence.Direct friction or bulging of the flexor tendons occurfrequently when plates are placed distal to the watershedline. Clinical studying with ultrasonography isnecessary to correspond these flexor tendon frictionor bulging reported on ultrasonography with clinicalsymptoms of flexor tendinopathy and to view the sustainabilityof pronator quadratus repair over time.

Introduction: The main goals of obesity intervention programs are decreasing body weight, fat mass and increasing lean mass. It is generally accepted that fat mass decreases with weight loss, but results on lean mass are inconsistent. The relation between weight-loss induced changes in body composition and fatigue sensations in obese adolescents remain unexplored. This study examined the effect of a 6 months weight loss program on self-perceived fatigue, grip performance and body composition.Methods: 81 obese boys (15±2 years) were examined for body composition (DXA), maximal grip strength, fatigue resistance (the time during which grip strength decreased to 50% of its maximum value during sustained maximal contraction), grip work (calculated as fatigue resistance x 0.75 x maximal grip strength, corresponding to the area under the curve) and self-perceived fatigue (Multidimensional Fatigue Inventory, MFI-20). The boys were divided into 2 groups; a high weight loss group (HWL, >20% body weight) and a low weight loss group (LWL