Hypermobililty spectrum disorders

Research and understanding of hypermobility syndromes is continuously developing, which means that the 2017 classification best describes the current state of knowledge. As further understanding is gained, the classifications may change, although it must be noted that as with hypermobile Ehlers-Danlos syndrome (hEDS), these are research criteria and are still in the process of being validated as diagnostic criteria. These criteria are not widely used in the NHS.

The HSD criteria can only be met when other conditions involving joint laxity have been excluded, eg EDS, Marfans or Downs syndrome.

There are four subtypes of HSD and an additional classification of asymptomatic hypermobility, but patients can move between these to reflect how they are affected over time.

This section focuses on the diagnosis of a hypermobility spectrum disorder. Our ‘Living with hypermobility’ section contains management advice based on the symptoms experienced.

Patients with HSD require the same validation and symptom-based management as individuals with hEDS or joint hypermobility syndrome (JHS) - they have the same range of potential symptoms and linked conditions. There is also no evidence of people meeting the hEDS criteria being more severely affected than those diagnosed as having HSD or JHS. As scientific understanding develops, some patients with HSD may turn out to have a connective tissue disorder too.

Generalised hypermobility spectrum disorder (gHSD): is assessed using the beighton score*, along with secondary musculo-skeletal manifestations (listed below)

Peripheral hypermobility spectrum disorder (pHSD): Joint hypermobility of the hands and feet, and 1 or more musculoskeletal manifestation (listed below)
Localised hypermobility spectrum disorder (lHSD): A single joint or group of joints is hypermobile, with one or more secondary musculoskeletal manifestations (listed below)
Historical hypermobility spectrum disorder (hHSD): Symptoms of gHSD are reported, but the individual is no longer as hypermobile as joints have stiffened with age, injury, or surgery etc.
Asymptomatic hypermobility: hypermobility is present, but without symptoms.

Although not part of the ‘criteria’, patients may also have a variety of associated conditions such as Fibromyalgia, IBS, PoTs and irritable bladder. The relationship between HSD and these is not yet fully understood.

*You can read more on the beighton score here, but it should always be borne in mind that the beighton score only covers a small number of joints, and only considers one plane of movement for each of those joints. If an individual scores low but has widespread hypermobility outside of the beighton scale, then generalised hypermobility may still be present.

Secondary musculoskeletal manifestations

Pain
Musculoskeletal /soft tissue trauma, including dislocations, subluxations and soft tissue damage, and microtraumas. Microtraumas are injuries which result from frequent, repeated use of muscles, tendons, ligaments, joints, and bones. This includes small tears in fibres and connective tissue of the muscles as well as sprained ligaments, strained muscles, and overstretched tendons.
Disturbed proprioception – the body’s sense of where it is in space, and the effort needed to move to the desired place doesn’t work too well, often mistaken for being ‘just clumsy’.
Other musculoskeletal/Orthopaedic traits that may be related to interactions between softer tissues and mechanical forces during growth – like flexible flat feet, misaligned bones in elbows or toes, and curvature of the spine.

Why a diagnosis of aysmptomatic hypermobility can be important.

A diagnosis of asymptomatic hypermobility encourages recognition that hypermobility does not automatically mean pain, disability, and health problems. Many patients who are given appropriate advice and support when symptoms start may find that symptoms improve significantly, and their diagnosis can change from generalised HSD to asymptomatic hypermobility.

It is helpful for an individual to know that they have asymptomatic hypermobility so that they can proactively manage their condition and respond appropriately to other symptoms should they develop.

There is the added benefit that should symptoms occur, unnecessary medical investigation can be prevented and time can be saved by starting from the knowledge that hypermobility could be the underlying issue.