What is hEDS?

1. Understanding hEDS: Key Features and Implications

2. Sex Bias in hEDS: Hormonal and Other Contributing Factors

3. Impact of hEDS on Children: Hypermobility, Pain, and Developmental Delays

4. How hEDS Evolves Over Time: From Hypermobility to Chronic Pain

   
   

The hEDS subtype is termed "hypermobile" due to one of its primary features: generalized joint hypermobility (JH), which is the ability to move joints beyond typical ranges of motion. This hypermobility can lead to pain, joint instability, muscle strain, postural issues, and other musculoskeletal problems. However, hEDS is not restricted to joint hypermobility alone. It is a multisystem disorder, meaning it can affect multiple organ systems. Since connective tissue is present throughout the body, hEDS can manifest in various ways that evolve over time.

The presence of pain without accompanying joint hypermobility is not sufficient for an EDS diagnosis. Over time, many patients experience a loss of joint laxity, while others maintain hypermobility. This reduction in JH as individuals age, particularly after 40, complicates the diagnostic process, especially in chronic pain patients.

Studies suggest that hEDS is a phenotypically and likely genetically heterogeneous condition with variable expressivity. It is primarily inherited as an autosomal dominant disorder affecting connective tissue. The reason for the sex bias remains unclear, but it is speculated that female sex hormones may play a role. It is also important to note that many chronic pain syndromes, including those associated with hEDS, exhibit a female predominance, which may contribute to this bias. Joint hypermobility is influenced by multiple factors, such as age, gender, weight, physical activity, and other variables.

In the early years of life, the "hypermobility" phase is dominant, often marked by extreme flexibility and a tendency for sprains and dislocations. Pain is typically confined to the lower limbs (e.g., persistent "growing pains"), but pain with fine motor tasks, such as handwriting, is also common. Easy fatigability, along with issues like voiding dysfunction, may be observed. Some hypermobile children develop developmental dyspraxia (or developmental coordination disorder), which can involve mild hypotonia and delays in achieving both gross and fine motor milestones.

The “pain” phase is characterized by generalization and progressive chronicity of musculoskeletal pain, which is often diagnosed as fibromyalgia [Ting et al., 2012], summation of other forms of chronic pain, such as pelvic pain (in women) and headache, as well as exacerbation of fatigue. This phase typically starts in the second to the fourth decade of life and often associates with a variegated constellation of additional complaints, such as paresthesias, mixed and treatment-resistant functional gastrointestinal disorders, orthostatic intolerance, and pelvic dysfunction. A generalized reduction of joint mobility dominates the “stiffness” phase, in which patients usually experience significant reduction in their functionality due to the combination of disabling symptoms (e.g., pain and fatigue) as well as motor limitations due to the coexistence of reduced muscle mass and weakness, defective proprioception, prior injuries, and arthritis. In this phase, observed in a few adults and elderly only, the symptomatology that appeared in the “pain” phase escalates and GJH is usually not appreciated.

References

1 Anne Maitland. Disjointed: Navigating the Diagnosis and Management of Hypermobile Ehlers-Danlos Syndrome and Hypermobility Spectrum Disorders. Hidden Stripes Publications, Incorporated, 2020

2  Tinkle B, Castori M, Berglund B, Cohen H, Grahame R, Kazkaz H, Levy H. Hypermobile Ehlers-Danlos syndrome (a.k.a. Ehlers-Danlos syndrome Type III and Ehlers-Danlos syndrome hypermobility type): Clinical description and natural history. Am J Med Genet C Semin Med Genet. 2017 Mar;175(1):48-69. doi: 10.1002/ajmg.c.31538. Epub 2017 Feb 1. PMID: 28145611.