Why Your Arch Collapses — Talonavicular Arthritis Explained ⏱ Chapters 0:00 Intro 0:51 The Keystone 1:23 Ball meets socket 1:49 The numbers 2:13 Grade It, Prove It 2:43 The grade decides 3:06 Read the standing film 3:33 Fuse It Right 4:10 One joint or three 4:42 Two screws, crossed 5:09 What lasts 5:41 Recap & sources The keystone joint, the half-motion rule, and fuse-it-right decisions In this OrthoVellum master lecture • Keystone joint: half the hindfoot motion lives here • Grades 1–2 brace six months; grade 3 fuses • Standing films: beaking, under 2mm, under 60% covered • Isolated spares cartilage; triple for pan-disease • Crossed screws, bleeding bone, 6–8 weeks dark • 85–90% unite; neighbours bill at 20–30% Full clinical topic and references: https://orthovellum.com/topics/talonavicular-arthritis Image credits • Popelka et al. — CC BY 2.0 — https://europepmc.org/article/PMC/2837861#1471-2474-11-38-5 • Laurent et al. — CC BY 4.0 — https://europepmc.org/article/PMC/13258229#jcm-15-03991-g003 • Popelka et al. — CC BY 2.0 — https://europepmc.org/article/PMC/2837861#1471-2474-11-38-3 • Gorbachova et al. — CC BY 4.0 — https://europepmc.org/article/PMC/8703616#jcm-10-05848-g006 • Lin et al. — CC BY 4.0 — https://europepmc.org/article/PMC/12786061#diagnostics-16-00018-g002 Educational only — not individual medical advice. #orthopaedics #orthopedics #medicaleducation #orthovellum Orthovellum.com