QUANTITATIVE ASSESSMENT OF MECHANICAL ANKLE LAXITY AND RELATIONSHIP WITH TALOCRURAL AND SUBTALAR JOINT RANGE OF MOTION IN STANCE PHASE OF WALKING

The purpose of this study was to examine the relationship between ankle joint laxity and talocrural and subtalar joint kinematics in healthy people. We obtained lateral fluoroscopic images from 6 healthy male volunteers during walking stance phase and three-dimensional bone positions were determined using 3D-2D model image registration technique. Ankle laxity was measured using instrumented arthrometry. The arthrometry mesurements of anteroposterior displacement and eversion had strong correlation with the range of motion of subtalar eversion/inversion. The quantitative measurement by ankle arthrometry is important to understanding the nature. Further research is needed to examine the linkage of joint laxity and abnormal kinematics for chronic ankle instability

Progressive Changes in Lumbopelvic Alignment during the Three Month-Postpartum Recovery Period

Pregnancy-related lumbopelvic pain is a common musculoskeletal problem, and postural changes are believed to be involved in these disorders. However, the lumbopelvic alignment changes in postpartum women remain unclear. This study aimed to determine whether there are changes in lumbopelvic alignment following vaginal or cesarean delivery and when these alignment changes occur after delivery. Thirty postpartum females (PP group) and 20 nulliparous female controls (CTL group) underwent anteroposterior, lateral pelvic, and lower-back X-ray in a static upright position. Digital radiographic images were analyzed and three radiographic variables, the pelvic incidence, pubic symphysis width, and sacral slope, were measured. The pubic symphysis width of the PP group was significantly larger immediately and one month after childbirth (PP group: 6.0 ± 1.1 mm (immediately), 5.0 ± 1.2 mm (one month); CTL group: 3.4 ± 0.4 mm; F = 31.79, p < 0.001). The sacrum slope in the PP group was significantly larger than in the CTL group 1 month after childbirth (PP group: 39.9 ± 6.6°; CTL group: 32.8 ± 5.1°; F = 2.59, p = 0.05). A two-way analysis of variance indicated no statistically significant main effects or interaction effects between the delivery modes on the pubic symphysis width or the sacrum slope. This study suggested that the course of lumbopelvic alignment progressed towards recovery for at least one month, and that these changes were independent of the delivery method

Changes in Foot Shape after Long-Distance Running

Changes in foot shape during long-distance running may lead to alteration in shoe fit. However, little information is available on changes in foot shape following long-distance running. The purpose of this study was to assess changes in foot shape in experienced runners after a single long-distance run. Data from the right feet of 21 subjects were obtained using a foot scanner before and after running 35 km on an asphalt road. After the run, the dorsal height, navicular height, and arch height ratio were significantly decreased. Midfoot cross-sectional shape after the run was deformed laterally compared to before running. Lateral deformity of the lateral dorsum was seen in 76.2% of the feet. For the medial side, 47.6% of feet deformed medially and 38.1% of feet did not change. The findings of the present study suggest that foot shape is altered during a single long-distance run. These results suggest that footwear fit and comfort could be affected during long distance running because athletes tie their shoelaces based on their pre-running foot shape