Marked skin hyperextensibility with widened atrophic scars and joint hypermobility are found. The skin manifestations range in severity from mild to severe expression. The skin is smooth and velvety with evidence of tissue fragility including hiatal hernia, anal prolapse in childhood, and cervical insufficiency. Hernias may be a post-operative complication. Also evident are molluscoid pseudotumors frequently found over pressure points and subcutaneous spheroids which are mobile and palpable on the forearms and shins.
Complications of joint hypermobility include sprains, dislocations/subluxations and pes planus. Recurrent subluxations are common in the shoulder, patella and temporomandibular joints. Muscle hypotonia and/or delayed gross motor development may be evident.
Abnormal electrophoretic mobility of the proa 1(V) or proa 2(V) chains of collagen type V has been detected. Inheritance: Autosomal dominant.