Hypermobility Spectrum Disorder (HSD): Testing, Diagnosis, and Management

How to Test for HSD?

Testing for Hypermobility Spectrum Disorder (HSD) primarily involves a comprehensive clinical evaluation by a healthcare professional, combining a detailed medical history, physical examination, and the application of specific diagnostic criteria like the Beighton Score, while ruling out other conditions.

Understanding Hypermobility Spectrum Disorder (HSD)

Hypermobility Spectrum Disorder (HSD) is a condition characterized by symptomatic joint hypermobility that does not meet the diagnostic criteria for other specific connective tissue disorders, such as hypermobile Ehlers-Danlos Syndrome (hEDS). While generalized joint hypermobility (GJH) refers to the presence of increased range of motion in multiple joints, HSD signifies that this hypermobility is causing symptoms like chronic pain, fatigue, instability, and other systemic manifestations. Distinguishing HSD from hEDS and other conditions is crucial for appropriate management and care.

The Role of Clinical Assessment in HSD Diagnosis

A definitive diagnosis of HSD is made by a qualified healthcare professional, typically a rheumatologist, geneticist, or a physician with expertise in connective tissue disorders. It is not something that can be self-diagnosed or confirmed through a simple test. The diagnostic process is holistic and involves:

• Detailed Medical History: The clinician will ask about your symptoms, their onset, severity, and impact on daily life. This includes joint pain, dislocations, subluxations, fatigue, autonomic dysfunction (e.g., POTS), gastrointestinal issues, skin fragility, and family history of hypermobility or connective tissue disorders.
• Physical Examination: A thorough physical assessment is conducted to evaluate joint range of motion, stability, muscle strength, proprioception, and to look for other physical signs associated with hypermobility.

Key Diagnostic Criteria and Tools

The diagnosis of HSD has evolved significantly, moving towards a more nuanced understanding beyond just joint flexibility.

The Beighton Score

The Beighton Score is a widely used, 9-point scale designed to assess generalized joint hypermobility (GJH). It is a screening tool, not a diagnostic tool for HSD or hEDS on its own. A high Beighton Score indicates generalized joint hypermobility, which is a prerequisite for HSD, but not sufficient for diagnosis.

The nine points are assessed as follows:

• Passive dorsiflexion of the 5th metacarpophalangeal (MCP) joint > 90 degrees: 1 point for each hand (2 points total).
• Passive apposition of the thumb to the forearm: 1 point for each thumb (2 points total).
• Hyperextension of the elbows > 10 degrees: 1 point for each arm (2 points total).
• Hyperextension of the knees > 10 degrees: 1 point for each leg (2 points total).
• Forward flexion of the trunk with palms flat on the floor: 1 point (1 point total).

Scoring: A score of 4/9 or 5/9 (depending on age and population) or higher typically indicates generalized joint hypermobility. Children and adolescents often have higher scores due to greater physiological flexibility.

Limitations: While useful for identifying GJH, the Beighton Score does not account for symptomatic hypermobility in specific joints, nor does it capture the full spectrum of systemic manifestations associated with HSD.

The 2017 International Classification for EDS and HSD

The current diagnostic framework for HSD stems from the 2017 International Classification for Ehlers-Danlos Syndromes. Under this classification, HSD is diagnosed when a patient presents with symptomatic generalized joint hypermobility (often, but not exclusively, indicated by a positive Beighton Score) and does not meet the more stringent and specific criteria for hypermobile Ehlers-Danlos Syndrome (hEDS) or any other defined connective tissue disorder.

The diagnosis of HSD is therefore a diagnosis of exclusion, meaning other conditions must be ruled out. The clinician will consider:

• Presence of GJH: Often confirmed with the Beighton Score.
• Presence of Symptoms: Chronic pain, instability, dislocations, fatigue, and other systemic issues attributable to hypermobility.
• Exclusion of hEDS: The patient must not meet the detailed criteria for hEDS (which includes specific systemic manifestations beyond GJH).
• Exclusion of Other Conditions: Ruling out other autoimmune, rheumatological, or genetic conditions that could explain the symptoms.

Beyond the Beighton Score: Comprehensive Assessment for HSD

A thorough HSD assessment goes far beyond simply calculating a Beighton Score. It involves a deep dive into the patient's overall health and functional status.

• Symptom Burden Assessment: Evaluating the severity and impact of pain (localized, widespread), fatigue, frequent joint injuries, and other associated symptoms.
• Functional Limitations: Understanding how hypermobility impacts daily activities, exercise, and quality of life.
• Associated Conditions: Screening for common comorbidities seen in hypermobility, such as:
  • Postural Orthostatic Tachycardia Syndrome (POTS)
  • Mast Cell Activation Syndrome (MCAS)
  • Gastrointestinal dysmotility (e.g., gastroparesis, IBS)
  • Anxiety disorders, depression, and proprioceptive deficits
  • Pelvic floor dysfunction
• Imaging and Lab Tests: These are generally not diagnostic for HSD itself. However, they may be used to:
  • Rule out other conditions (e.g., inflammatory arthritis, muscle disease).
  • Assess for complications of hypermobility (e.g., signs of joint degeneration, disc herniation).
  • Genetic testing may be pursued if there's suspicion of other specific Ehlers-Danlos Syndrome types or other genetic connective tissue disorders.

Who Should You See for an HSD Assessment?

If you suspect you have HSD due to symptomatic hypermobility, the following healthcare professionals are typically involved:

• Primary Care Physician (PCP): Your first point of contact. They can conduct an initial assessment, rule out common conditions, and provide referrals to specialists.
• Rheumatologist: Specialists in musculoskeletal and systemic autoimmune diseases, often the primary diagnosticians for HSD and hEDS.
• Geneticist: Essential if there is a suspicion of a broader genetic connective tissue disorder, especially if hEDS or other EDS types are being considered.
• Physical Therapist/Physiotherapist: While not diagnosticians, they are crucial for conservative management, developing strengthening programs, improving proprioception, and managing pain and instability once a diagnosis is made.
• Other Specialists: Depending on associated symptoms, you may be referred to cardiologists (for POTS), gastroenterologists (for GI issues), neurologists, or pain management specialists.

Implications of an HSD Diagnosis

Receiving an HSD diagnosis is significant. It provides a framework for understanding your symptoms and guides a personalized management plan focused on:

• Education: Understanding the condition and its impact.
• Strengthening: Building muscle support around unstable joints.
• Proprioception Training: Improving body awareness and joint stability.
• Pain Management: Utilizing various strategies including physical therapy, medications, and lifestyle adjustments.
• Injury Prevention: Learning safe movement patterns and activity modification.
• Addressing Co-occurring Conditions: Managing the systemic issues often associated with HSD.

Self-Screening for Awareness (Not Diagnosis)

While you cannot self-diagnose HSD, you can perform a basic self-assessment of joint hypermobility and note any related symptoms that warrant a professional medical evaluation. If you consistently score high on the Beighton maneuvers and experience chronic joint pain, frequent sprains/subluxations, fatigue, or other systemic issues, it is advisable to discuss these concerns with your doctor.

Consider seeking professional advice if you experience:

• Chronic, unexplained joint pain in multiple joints.
• Joints that frequently click, pop, or feel unstable.
• Easy bruising or fragile skin.
• Frequent sprains, strains, or dislocations.
• Chronic fatigue without an obvious cause.
• Digestive issues (e.g., IBS, unexplained abdominal pain).
• Symptoms of dizziness, lightheadedness, or rapid heart rate upon standing (POTS).
• A family history of joint hypermobility or related conditions.

Understanding the complexity of HSD diagnosis empowers individuals to advocate for comprehensive evaluation and appropriate management, leading to improved quality of life.