Introduction Form of disproportionate short-trunk dwarfism a Type II collagenopathy Genetics autosomal dominant defect in COL2A1 (missense, splice or deletion) defect leads to abnormal Type II collagen, chondrocyte degeneration, cytoplasmic inclusions Associated conditions orthopaedic manifestations short stature disproportionate short-trunk dwarfism joint stiffness / contractures dumbell-shaped femora hypoplastic pelvis and spine scoliosis & kyphosis early osteoarthritis medical conditions respiratory problems cleft palate retinal detachment and myopia otitis media with hearing loss Presentation Physical exam disproportionate short-trunk dwarfism joints enlarged and stiff scoliosis & kyphosis cleft lip round face with central depression prominent eyes bell-shaped chest Imaging Radiographs osteopenia dumbbell-shaped metaphyseal bone coxa vara genu valgum Treatment Myopia ophthalmologic consultation Joint contractures early physical therapy Hip degenerative arthritis joint reconstruction