Kadhum Murtaza, Lee Mu-Huan, Czernuszka Jan, Lavy Chris
Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Science, Oxford University, UK.
Department of Materials, Oxford University, UK.
Appl Bionics Biomech. 2019 Mar 25;2019:4308462. doi: 10.1155/2019/4308462. eCollection 2019.
Congenital clubfoot is a complex pediatric foot deformity, occurring in approximately 1 in 1000 live births and resulting in significant disability, deformity, and pain if left untreated. The Ponseti method of manipulation is widely recognized as the gold standard treatment for congenital clubfoot; however, its mechanical aspects have not yet been fully explored. During the multiple manipulation-casting cycles, the tendons and ligaments on the medial and posterior aspect of the foot and ankle, which are identified as the rate-limiting tissues, usually undergo weekly sequential stretches, with a plaster of Paris cast applied after the stretch to maintain the length gained. This triggers extracellular matrix remodeling and tissue growth, but due to the viscoelastic properties of tendons and ligaments, the initial strain size, rate, and loading history will affect the relaxation behavior and mechanical strength of the tissue. To increase the efficiency of the Ponseti treatment, we discuss the theoretical possibilities of decreasing the size of the strain step and interval of casting and/or increasing the overall number of casts. This modification may provide more tensile stimuli, allow more time for remodeling, and preserve the mechanical integrity of the soft tissues.
先天性马蹄内翻足是一种复杂的小儿足部畸形，发生率约为千分之一活产儿，若不治疗会导致严重残疾、畸形和疼痛。庞塞蒂手法治疗被广泛认为是先天性马蹄内翻足的金标准治疗方法；然而，其力学方面尚未得到充分探索。在多次手法-石膏固定周期中，足踝内侧和后侧的肌腱和韧带被确定为限速组织，通常每周进行连续拉伸，拉伸后应用石膏固定以维持获得的长度。这会引发细胞外基质重塑和组织生长，但由于肌腱和韧带的粘弹性，初始应变大小、速率和加载历史会影响组织的松弛行为和力学强度。为提高庞塞蒂治疗的效率，我们讨论了减小应变步长和石膏固定间隔大小和/或增加石膏固定总数的理论可能性。这种改进可能会提供更多拉伸刺激，留出更多时间进行重塑，并保持软组织的力学完整性。
