No Biochemical Test Currently Available for Diagnosing Joint Hypermobility in Adults
There is no validated biochemical test to diagnose hypermobile joints in adults; diagnosis relies on clinical assessment using the Beighton scoring system. 1
Current Diagnostic Approach
The diagnosis of joint hypermobility and related conditions (hypermobile Ehlers-Danlos syndrome [hEDS] and hypermobility spectrum disorders [HSD]) remains entirely clinical based on the 2017 international consensus criteria 1. The cornerstone of assessment is:
The Beighton Score (Physical Examination)
- For adults under 50 years: ≥5/9 points indicates generalized joint hypermobility
- For adults 50+ years: ≥4/9 points indicates generalized joint hypermobility 1
The nine-point system assesses:
- Bilateral 5th finger hyperextension >90° (2 points)
- Bilateral thumb-to-forearm apposition (2 points)
- Bilateral elbow hyperextension >10° (2 points)
- Bilateral knee hyperextension >10° (2 points)
- Forward trunk flexion with palms flat on floor (1 point) 1
Emerging Research on Biomarkers
While no clinically available biochemical test exists, recent 2025 research has identified potential plasma biomarkers showing distinctive extracellular matrix (ECM) fragmentation patterns in hEDS/HSD patients 2. Specifically, Western blotting detected unique fibronectin and type I collagen fragment signatures in patient plasma that distinguished hEDS/HSD from other conditions. However, this remains investigational and is not yet validated for clinical use 2.
Role of Genetic Testing
Genetic testing does NOT diagnose hEDS/HSD but serves to exclude other Ehlers-Danlos syndrome subtypes and alternative diagnoses 3. In a 2025 study, genetic testing identified alternative or additional diagnoses in 26.4% of patients who initially met hEDS criteria, highlighting its importance in the exclusion process 3. However, the molecular etiology of hEDS itself remains unknown 3.
Clinical Pitfalls
Do not rely solely on Beighton score: It predominantly assesses upper limb joints and may miss hypermobility in other major joints 4. Clinical judgment about generalized hypermobility beyond the scored joints is essential.
The Beighton score was designed as an epidemiological screening tool, not originally as a definitive diagnostic instrument 4, 5. Use it as part of comprehensive clinical assessment including musculoskeletal complications, skin findings, and systemic manifestations 1.
Age-adjusted cutoffs are critical: Using adult cutoffs in children overdiagnoses hypermobility, as children naturally have greater joint mobility 6.
Practical Recommendation
Gastroenterologists and other specialists should incorporate the Beighton score as a screening tool when evaluating patients with disorders of gut-brain interaction (DGBI), as there are significant associations between hEDS/HSD and gastrointestinal symptoms 1. If screening is positive, apply the full 2017 diagnostic criteria or refer to appropriate specialists 1.
The absence of a biochemical test means diagnosis requires clinical expertise in recognizing the constellation of joint hypermobility, skin changes (soft/velvety skin, atrophic scars), and associated multisystemic features rather than laboratory confirmation.