Being “double jointed” doesn’t mean you have extra joints or two joints where others have one. It’s a colloquial term for joint hypermobility, a condition where your joints move beyond the normal range of motion. Somewhere between 2% and 57% of the population has some degree of generalized joint hypermobility, with the wide range depending on age, gender, and ethnicity. For most people it’s harmless, but about 10% of those with hypermobile joints develop physical or psychological symptoms that affect daily life.
What’s Actually Happening in Your Joints
Your joints are held together by ligaments, which are bands of connective tissue made primarily of collagen. In people with hypermobile joints, the collagen that strengthens those ligaments is structurally different. It’s not that the ligaments are missing or damaged. The collagen fibers themselves are organized differently, making the tissue stretchier and less supportive than usual.
Research in connective tissue biology has shown that the hyperextensibility seen in hypermobile people likely reflects disarray in how collagen fibers are bundled together rather than the individual fibers being more elastic. Think of it like a rope: the same fibers woven tightly create a stiff, strong rope, but loosely bundled, they allow much more flex. This is a genetic trait, meaning you’re born with it. The genes involved in collagen production are passed down from parents, which is why hypermobility often runs in families.
How Doctors Measure Hypermobility
The standard clinical tool is called the Beighton Score, a nine-point system based on five simple physical tests performed on both sides of the body:
- Pinky fingers: Bending each little finger backward past 90 degrees (one point per hand)
- Thumbs: Bending each thumb back to touch the forearm (one point per hand)
- Elbows: Straightening each elbow past neutral so it curves backward (one point per arm)
- Knees: Straightening each knee past neutral so it bows backward (one point per leg)
- Forward bend: Placing both palms flat on the floor with straight knees (one point)
A score of four or more generally indicates joint hypermobility. You can try these at home to get a rough sense of where you fall, though a formal assessment also includes questions about your history of joint flexibility.
When Flexibility Becomes a Problem
Many hypermobile people never experience issues. Dancers, gymnasts, and musicians sometimes benefit from the extra range of motion. Problems arise when the loose ligaments can’t adequately stabilize joints during everyday activities, leading to a cluster of symptoms collectively known as joint hypermobility syndrome.
The most common complaints are joint pain, particularly after physical activity or prolonged standing, and a tendency toward joint subluxations (partial dislocations) or full dislocations. Because collagen is found throughout the body, not just in joints, symptoms can extend well beyond stiff knees or sore shoulders. People with symptomatic hypermobility frequently report chronic fatigue, digestive problems, anxiety, dizziness when standing up (a sign of orthostatic intolerance), and pelvic or bladder issues. These systemic symptoms catch many people off guard because they don’t seem related to flexible joints, but they trace back to the same underlying connective tissue differences.
Hypermobility Spectrum Disorders and Ehlers-Danlos Syndrome
Since 2017, the medical community has used more specific terminology to classify symptomatic hypermobility. If you meet a strict set of diagnostic criteria that includes joint hypermobility, certain skin findings (such as unusually soft or stretchy skin), and recurrent joint dislocations or chronic pain, the diagnosis is hypermobile Ehlers-Danlos syndrome (hEDS). It’s inherited in an autosomal dominant pattern, meaning you only need the gene from one parent, though no specific genetic mutation has been identified yet.
If you have symptomatic hypermobility but don’t meet the full criteria for hEDS, the diagnosis falls under hypermobility spectrum disorders (HSD). This isn’t a lesser condition. People with HSD can still experience significant pain, fatigue, and reduced quality of life. The distinction matters mainly for research and for ruling out rarer connective tissue disorders that require different management.
Strengthening Joints That Move Too Much
The core strategy for managing hypermobility is building muscle strength around loose joints so the muscles compensate for what the ligaments can’t do. This starts with neuromuscular training, exercises designed to improve your awareness of where your joints are in space (proprioception) and to activate the deep stabilizing muscles before adding any resistance or load. Exercises like core activation, scapular stabilizer work, and postural training form the foundation.
From there, progressive resistance training is introduced, typically starting in supported positions like lying down or sitting, using body weight or light resistance bands before advancing to standing exercises with heavier loads. The key principle is avoiding joint hyperextension during exercise. Locking your knees or elbows past neutral under load is exactly what causes problems, so learning to stop at neutral is a skill hypermobile people need to actively develop.
Aerobic exercise is also important. Walking, swimming, cycling (recumbent bikes work well for people with lower body issues), rowing, and water-based exercises are all recommended. High-impact activities like running or sports with sudden stops and direction changes are generally discouraged if you have joint pain or arthritis, since they place repeated stress on already vulnerable joints. A practical guideline from rehabilitation programs: if pain increases and persists more than two hours after finishing exercise, you’ve done too much and should scale back next time.
Practical Tools for Daily Life
Several types of braces and supports can help manage hypermobility day to day. Proprioceptive braces, made of flexible materials like neoprene, apply light compression to improve your body’s awareness of joint position without restricting movement. Because they don’t immobilize the joint, they’re less likely to cause muscle loss from disuse.
Ring splints are one of the most widely used tools for hypermobile fingers. These small splints sit across finger joints and prevent them from bending backward past neutral, reducing pain and making tasks like writing, typing, and gripping more comfortable. For ankles and feet, functional braces that allow controlled movement can correct walking patterns and reduce overload injuries. In-shoe orthotics provide additional foot support by redistributing pressure.
Rigid resting splints serve a different purpose. They’re typically used for pain relief and protection after a dislocation or during sleep, when you can’t consciously control your joint positions. Some people with significant nighttime pain or frequent dislocations wear wrist or knee splints to bed to maintain alignment.
Mobility aids like canes or walking sticks can help people who have difficulty getting around due to joint instability or pain, though consistent joint-friendly exercise remains important even when using these tools to maintain muscle tone and prevent deconditioning.