What is the Beighton scale and how is it used to assess joint hypermobility?

The Beighton Scale: Assessment Tool for Joint Hypermobility

The Beighton scale is a standardized 9-point scoring system used to assess generalized joint hypermobility, which is critical for diagnosing conditions like Ehlers-Danlos Syndrome (EDS) and identifying patients at risk for joint-related morbidity and complications. 1

Components of the Beighton Scale

The Beighton scale evaluates hypermobility in five areas of the body, with a maximum score of 9 points:

• Fifth fingers (pinkies): Passive dorsiflexion of each fifth finger beyond 90 degrees (1 point each side) 1
• Thumbs: Passive apposition of each thumb to the flexor surface of the forearm (1 point each side) 1
• Elbows: Hyperextension of each elbow beyond 10 degrees (1 point each side) 1
• Knees: Hyperextension of each knee beyond 10 degrees (1 point each side) 1
• Spine/Forward bend: Ability to place palms flat on the floor when bending forward with knees fully extended (1 point) 1

Scoring Interpretation

The threshold for diagnosing generalized joint hypermobility varies by age:

• Children before puberty: ≥6/9 points 1
• Adults up to age 50: ≥5/9 points 1
• Adults over age 50: ≥4/9 points 1

Clinical Application

Diagnostic Use in EDS

• The Beighton scale is a major diagnostic criterion for hypermobile EDS (hEDS), the most common EDS subtype 1
• For hEDS diagnosis, a score of ≥5 must be accompanied by other criteria including skin abnormalities and absence of tissue fragility 1
• Medical geneticists typically coordinate EDS diagnosis, with rheumatologists often performing the joint hypermobility assessment 2

Screening Approach

1. Perform the five maneuvers described above, assigning points for each positive finding 1
2. Calculate the total score (0-9 points) 1
3. Compare to age-appropriate thresholds 1
4. If threshold is met, consider further evaluation for associated conditions 1

Clinical Significance

• Identifying hypermobility is crucial as it may indicate underlying connective tissue disorders with potential cardiovascular, gastrointestinal, and neurological complications 1, 2
• Patients with hypermobility are at increased risk for joint dislocations, sprains, chronic pain, and fatigue 3
• Up to 60% of patients with hEDS experience gastrointestinal symptoms 1
• Approximately 25-33% of patients with hypermobile EDS develop aortic root dilation requiring cardiovascular monitoring 1

Limitations and Considerations

• The Beighton scale predominantly assesses upper limb joints and may not fully capture hypermobility in other major joints 4
• Reliability studies show substantial to excellent inter-rater and intra-rater reliability, though methodological quality varies across studies 5
• Recent research questions the construct validity of the Beighton scale in certain populations, such as athletes 6
• For children under 5 years, a modified version of the Beighton scale may be more appropriate, with a score >4 indicating hypermobility 7

Next Steps After Positive Screening

If a patient scores above the age-appropriate threshold:

• Consider referral to medical genetics for comprehensive evaluation 2
• Obtain echocardiogram to evaluate for aortic root dilation 1
• Assess for comorbid conditions like POTS (postural orthostatic tachycardia syndrome) 1
• Evaluate for gastrointestinal manifestations, which are common in hypermobile patients 1

The Beighton scale should not be used in isolation but as part of a comprehensive assessment for diagnosing hypermobility syndromes, with clinical judgment remaining essential for accurate diagnosis 4, 3.