Ligamentous Laxity/Hypermobility Syndrome/Joint Hypermobility Syndrome (JHS)
Consist of a group of patients with large range of joint motions – should be considered as a graded trait – the definition of ‘generalised hypermobility’ is somewhat arbitrary and is often based on a scoring system. Epidemiology is not clear – depends on definition used in studies. Hypermobility is seen as some authors as a physiological variation, being at the upper end of a normal distribution which may result in self limiting joint pain. It is seen by other authors as a pathological entity as part of a group of conditions known as the heritable disorders of connective tissue (HDCT).
Some have a specific genetic syndrome associated with hypermobility – Ehlers-Danlos syndrome, familial articular hypermobility syndrome, Larsen syndrome, Marfan syndrome.
Those with hypermobility are considered at greater risk of osteoarthritis – could be for three hypothetical reasons:
1) The genetic factors that contribute to the collagen abnormality of the hypermobility may also contribute to the osteoarthritis
2) Biomechanical factors associated with the hypermobility
3) Proprioceptive deficits
Other common clinical feature of joint hypermobility syndrome include a predisposition to the effects of trauma (from the ‘fragile’ connective tissues) and fibromyalgia syndrome. Other findings include anxiety states; falls (from proprioceptive deficits); lack of efficacy of local anaesthetics (mechanism unknown); chronic pain syndromes; autonomic dysfunction