Table 3 Disorders predisposing to bone fragility which can be associated with joint hypermobility Munns and Sillence[11].
From: The differential diagnosis of children with joint hypermobility: a review of the literature
Type | Inheritance | Discriminatory features | Other features | Laboratory |
|---|---|---|---|---|
Osteogenesis imperfecta type I | AD | Blue sclera Hypermobility, especially of small joints Wormian bones (70% of subjects) Generalised osteopenia on DEXA | Kyphoscoliosis Arcus cornea Hearing impairment Metatarsus varus Easy bruising Fractures from minimal trauma Opalescent dentine | Reduction in synthesis of type I procollagen Abnormalities in COL1A1 |
Osteogenesis imperfecta type I with opalescent dentine | AD | As above with opalescent dentine | Â | Â |
Osteogenesis imperfecta type IV | AD | White sclera Fractures from minimal trauma Short stature Wormian bones in 50–70% | Progressive long bone deformity Joint hypermobility | COL1A1 or COL1A2 mutations which reduce collagen stability. |
Osteogenesis imperfecta type IV with opalescent dentine | AD | As above with opalescent dentine | Â | Â |
Geroderma osteodysplasticum | AR | Osteopenia Platyspondyly Learning disability Joint hypermobility Skin hyperelasticity | Wormian bones | Â |