Final answer:
The question refers to Ehlers-Danlos syndrome (EDS), a genetic disorder characterized by hyperflexible joints and highly extensible skin, caused by issues with collagen production.
Step-by-step explanation:
The defects in collagen matrix structure causing hyperflexible joints and highly extensible skin are usually referred to as Ehlers-Danlos syndrome (EDS). EDS is a genetic disorder where there is a deficiency in type-III collagen, or mutations in the amino acid sequences in collagen synthesis, leading to a deterioration of collagens. This affects various sites in the body such as joints and arterial walls, with major symptoms being skin and vascular problems.