Placing joint hypermobility in context: traits, disorders and syndromes

Area of Science:

• Connective tissue disorders
• Musculoskeletal health
• Genetics and rare diseases

Background:

• Joint hypermobility (JHM) is a prevalent physical trait, often associated with musculoskeletal (MSK) pain.
• Hypermobility Spectrum Disorders (HSD) are diagnosed when JHM and MSK pain lack an alternative diagnosis.
• Ehlers-Danlos Syndromes (EDS) are rare inherited connective tissue disorders with JHM and diverse manifestations; the 2017 classification details 13 subtypes.

Purpose of the Study:

• To define and present the epidemiology, assessment, and patterns of JHM.
• To illustrate the nature of the 2017 EDS Classification and the concept of a 'spectrum' of hypermobility-related conditions.
• To discuss current limitations and controversies surrounding HSD and Hypermobile EDS (HEDS).

Main Methods:

• A literature review focused on key arguments, prioritizing papers published after the 2017 EDS Classification.
• Synthesis of information regarding definitions, epidemiology, and assessment tools for JHM.
• Analysis of existing literature to identify areas of agreement and controversy in hypermobility classification.

Main Results:

• The 2017 EDS Classification identifies 13 subtypes, with Hypermobile EDS (HEDS) currently lacking a confirmatory diagnostic test.
• The 'spectrum' concept in hypermobility disorders is presented, alongside definitions and epidemiological data for JHM and HSD.
• Current limitations and disagreements in the classification and diagnosis of HSD and HEDS are highlighted.

Conclusions:

• Elucidating the pathophysiology of JHM-related pain requires parallel investigation of associated pleiotropic manifestations.
• Future research should address challenges in classification, nosology, diagnosis, and management of JHM, EDS, and related disorders.
• The review underscores the need for continued research into the complex interplay of genetics, pain, and systemic features in hypermobility syndromes.