Lifelong bound feet in China: a quantitative ultrasound and lifestyle questionnaire study in postmenopausal women

Understanding the form and function in Chinese bound foot from last-generation cases

Purpose: Foot adaptation in the typically developed foot is well explored. In this study, we aimed to explore the form and function of an atypical foot, the Chinese bound foot, which had a history of over a thousand years but is not practised anymore. Methods: We evaluated the foot shape and posture via a statistical shape modelling analysis, gait plantar loading distribution via gait analysis, and bone density adaptation via implementing finite element simulation and bone remodelling prediction. Results: The atypical foot with binding practice led to increased foot arch and vertically oriented calcaneus with larger size at the articulation, apart from smaller metatarsals compared with a typically developed foot. This shape change causes the tibia, which typically acts as a load transfer beam and shock absorber, to extend its function all the way through the talus to the calcaneus. This is evident in the bound foot by i) the reduced center of pressure trajectory in the medial-lateral direction, suggesting a reduced supination-pronation; ii) the increased density and stress in the talus-calcaneus articulation; and iii) the increased bone growth in the bound foot at articulation joints in the tibia, talus, and calcaneus. Conclusion: Knowledge from the last-generation bound foot cases may provide insights into the understanding of bone resorption and adaptation in response to different loading profiles.

Foot binding in a Ming dynasty cemetery near Xi'an, China

This paper describes the morphology of the feet of a population of elite women from the Ming dynasty (1368-1644 CE) in Shaanxi province. This is a social stratum, time, and place in which foot binding was practiced. Among a group of 31 skeletons exhumed from the cemetery, eight were women with well-preserved foot bones. Macroscopic examination revealed that half these women (4/8) had clearly altered foot bones: the metatarsal bones, and the few observable phalanges, were gracile and small, while the tarsal bones exhibited a slight reduction in size but no dramatic change in morphology. The other half of the women (4/8) had apparently unmodified metatarsal bones. T-tests comparing linear measurements of the foot bones between the two groups revealed that metatarsal bones were the most affected by binding, and among the tarsal bones, the talar trochlea and calcaneal dimensions were most impacted. This small group of skeletons reveals that some elite women in Shaanxi apparently still did not practice foot binding in the late Ming dynasty, or practiced a much milder form of foot binding, and that there was considerable variation even among those who did practice it.

Cartilage Stiffness Effect on Foot Biomechanics of Chinese Bound Foot: A Finite Element Analysis

The purpose of this study is to investigate the effect of cartilage stiffness on inner foot biomechanics of Chinese bound foot while balanced standing using finite element method. A three-dimensional FE model of bound foot involving 28 bones, 72 ligaments, 5 plantar fascia, cartilages, and encapsulated soft tissue was constructed and validated. To conduct the sensitivity analysis of cartilage stiffness, the incremental Young’s modulus of 1, 5, 10, and 15 MPa were assigned to the cartilage. 25% of the body weight was applied to the Achilles tendon to adjust the anterior- posterior displacement of center of pressure agreeable with the measured result. As the Young’s modulus of cartilage increased, the peak von Mises stress in the fifth metatarsal increased obviously, while that in the calcaneus remains unchanged. The plantar fascia experienced reduced total tension with stiffer cartilage. The cartilage stiffening also caused a general increase of contact pressure at mid- and forefoot joints. Cartilage stiffening due to foot binding gave rise to risks of foot pain and longitude arch damage. Knowledge of this study contributes to the understanding of bound foot biomechanical behavior and demonstrating the mechanism of long-term injury and function damage in terms of weight-bearing due to foot binding.

Case 255: Foot Binding

History A 99-year-old Chinese-Indonesian woman with a longstanding history of diabetes mellitus was admitted for chest infection and was incidentally found to have bilateral deformed feet. She was otherwise asymptomatic and could ambulate independently. Photographs and radiographs of the feet were obtained.