The purpose of this study was to test pathogenetic models for the "unprovoked" ankle inversion injuries seen in functional ankle unstable subjects. The consequence of spatial mal-alignment of the ankle/foot complex on the risk of producing an ankle inversion torque at heel-strike and during swing-phase follow through was analyzed in cadaver simulations. Heel-strike was simulated using a 5 degrees of freedom rig in a material testing machine. A set-up capable of accelerating lower limb specimens towards a support surface simulated swing-phase follow through. Joint excursions were monitored with flexible wire goniometers. The unloaded ankle/foot complex was placed in increasing positions of talar and subtalar joint excursions. The consequences of these settings on the behavior of the ankle/foot complex at heel-strike and when the lateral part of the foot "caught" the ground during swing-phase follow through were monitored. An inversion torque at heel-strike was first seen when the unloaded foot was set in positions exceeding 30 degrees of inversion combined with full plantar flexion and 10 degrees of internal tibial rotation. A collision between the lateral border of a 20 degrees inverted, but otherwise neutral ankle/foot complex and the ground surface during swing-phase follow through forced the foot into the full limit of inversion, plantar flexion and internal tibial rotation measurable in this set-up. Clinical consequence: The study showed that the foot/ankle complex exhibits a high degree of intrinsic stability at heel-strike. The foot will thus stabilize itself and move into normal eversion at the beginning of the stance-phase even though it is set to the ground in a substantial degree of mal-alignment. In contrast, the swing-phase collision model provides a link that can connect the small deficits in inversion angle awareness measured in chronic functional ankle unstable subjects with an increased risk in this group of sustaining ankle inversion injuries.
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JBJS Essent Surg Tech
January 2025
The Ohio State University College of Medicine, Columbus, Ohio.
Background: An all-inside endoscopic flexor hallucis longus (FHL) tendon transfer is indicated for the treatment of chronic, full-thickness Achilles tendon defects. The aim of this procedure is to restore function of the gastrocnemius-soleus complex while avoiding the wound complications associated with open procedures.
Description: This procedure can be performed through 2 endoscopic portals, a posteromedial portal (the working portal) and a posterolateral portal (the visualization portal).
Foot Ankle Surg
December 2024
Faculty of Medicine, University of Barcelona, Spain; Clínica Nostra Senyora del Remei, Barcelona, Spain; Unitat d`Anatomia i Embriologia Humana, Spain.
Introduction: There is evidence that the presence of a posterior malleolus fracture (PMF) worsens the prognosis of ankle fractures, making conservative treatment a poor choice. PMFs include a heterogeneous group of bone injury patterns that are sometimes associated to medial malleolus extensions, as well as fibula fractures or syndesmotic damage. This requires the surgeon to be well-versed in anatomy to choose the appropriate surgical approach.
View Article and Find Full Text PDFSci Rep
November 2024
Key Laboratory of Bionic Engineering, Ministry of Education, Jilin University, Changchun, 130022, China.
Studies focusing on the kinematics of the ankle joint complex (AJC) have long been a key area of interest for biomechanists and orthopedic surgeons. However, it is not clear how additional weight-bearing walking affects the motion of the AJC compared to walking with a normal body weight (BW) or what adjustments the AJC would instinctively make to accommodate the additional load. To address this gap in knowledge, advanced dynamic biplane radiography combined with a model-based 2D-3D tracking technique was employed to elucidate the inherent kinematics of the AJC during the stance phase while walking with and without additional weight-bearing.
View Article and Find Full Text PDFComput Med Imaging Graph
December 2024
Key Laboratory of Biorheological Science and Technology, Bioengineering College, Chongqing University, China. Electronic address:
Accurate segmentation of ankle and foot bones from CT scans is essential for morphological analysis. Ankle and foot bone segmentation challenges due to the blurred bone boundaries, narrow inter-bone gaps, gaps in the cortical shell, and uneven spongy bone textures. Our study endeavors to create a deep learning framework that harnesses advantages of 3D deep learning and tackles the hurdles in accurately segmenting ankle and foot bones from clinical CT scans.
View Article and Find Full Text PDFNeuromodulation
October 2024
Department of Anesthesiology and Perioperative Medicine, Mayo Clinic, Rochester, MN, USA.
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