External Pressure at Calf Region in Low Lithotomy Position is Higher in Men and Increases Proportionately with Height, Weight, Lower Leg Size, and Foot Length

Abstract Objective Patients placed in lithotomy position (LP) with a leg holder during surgical procedures have been at particular risk of developing well leg compartment syndrome (WLCS). A commonly considered contributing factor of WLCS is obesity. LP is mainly divided into the following four types by the degree of hip angulation and height of lower leg placement relative to the heart: low, standard, high, and exaggerated. We have reported that the external pressure at the calf region in standard LP is independent of weight. In the present study, we investigated the relationship between the external pressure in low LP and physical characteristics, such as body, leg, and foot sizes. Methods Fifty-five volunteers, 27 men and 28 women, participated in this study. They were placed in low LP with the boot-support-type leg holder, with the hip joints flexed at 170° from the trunk and abducted at 45°, and with the knee joints flexed at 120°. Peak contact pressure (PCP) at the calf region was measured as representative external pressure by using the pressure distribution measurement system, BIG-MAT®. Results The mean PCPs at the left and right calf regions in men (37.6 and 39.3 mmHg, respectively) were significantly higher than those in women (31.5 and 33.6 mmHg [P = 0.014 and 0.001], respectively). The left PCPs correlated positively with height (P = 0.003), weight (P = 0.001), body mass index (BMI) (P = 0.037), tibial length (TL) (P Conclusion The external pressure at the calf region in low LP is higher in men and increases proportionately with height, weight, lower leg size, and FL, which may contribute to the risks of inducing WLCS during surgeries performed in low LP.