Joint hypermobility in children: what is it and how does it affect posture, coordination and fitness?

About generalised joint hypermobility (GJH)

The term generalised joint hypermobility (GJH) is used when a child has several joints that are more flexible than usual. This happens when the connective tissue which makes up the joint structures (capsule and ligaments) is more compliant (more easily stretched) than usual.

Generalised joint hypermobility is quite a common occurrence - in fact it is just a normal variation in the way joints are put together. Most  ballet dancers and gymnasts have a degree of joint hypermobility - which means that you can be hypermobile, strong, active and fit.

Yet many children with hypermobile joints have movement difficulties. Why is this and what can be done to overcome these difficulties? 

For physical and occupational therapists: Joint Hypermobilityand EDS:  a more technical report with diagnostic criteria and references.  

A word about terminology

The term Joint Hypermobility Syndrome refers to a health condition which includes joint hypermobility along with pain and loss of function and as well as with several related symptoms such as fibromyalgia, anxiety, low blood pressure and fatigue. 

Some people with very hypermobile joints which are unstable and may or may not partially dislocate also have a diagnosis of Ehlers Danlos Syndrome (Hypermobility Subtype). Ehlers Danlos is a genetic disorder which affects the structure of the connective tissue that holds the joint in place (joint capsule and ligaments) and connects the muscles to the bones via tendons and fascial sheaths. The poorly formed connective tissue also affects the skin which is velvety and very pliable (easily stretched). 

Some medial experts do not differentiate clinically between JHS and Ehlers Danlos (Hypermobility Type).  Please see the article by Tofts et al  (2009)   The differential diagnosis of children with joint hypermobility

A child with Ehlers Danlos should be under the care of a paediatric rheumatologist and a physiotherapist with experience in this condition. 

Please note that this page provides information on children with generalised joint hypermobility. It does not apply directly to children who have Ehlers Danlos Syndrome (Hypermobility Subtype) or a diagnosis of joint hypermobility syndrome.

What is generalised joint hypermobility?

Joints are held together by a joint capsule and  ligaments which are made up of connective tissue. Connective tissue is a stiff but pliable material that has just enough give to allow the joint capsule and ligaments to stretch a little bit when the joint is moved  but still holds the joint surfaces together quite firmly. 

In generalised  joint hypermobility  the connective tissue has more give than usual and  as a result the joint surfaces are less firmly held  together, are less stable and the joint is able to move further than normal. 

How the ligaments work to keep the knee stable

Normally the knee can only extend to the point where the thigh and the lower leg are aligned in a straight line. In this picture you see the many sturdy ligaments at the back of the knee which serve to block the knee from extending beyond a straight line. 

knee joint.gifskeleton lat.jpg

If these ligaments are lax, the knee can extend beyond a straight line. The child stands with the knees in hyperextension. 

Children who stand with the knees in hyperextension will have a hollow back with the pelvis titled forwards. 

knee hyperextension.jpg  knee hyperextension_1.jpg

Here you see the very many small ligaments that support the ankle joint and help to maintain the arches of the foot. 

If these ligaments are very lax the child develops flat feet and a tendency to spraining the ankle joint if the muscles are not strong enough the provide the extra support that is needed. . 


How hypermobility affects different joints 

elbow extension.jpgThe elbow can be extended to form a backward angle.

wrist flexion.jpgThe wrist can be bent so the the thumb touches (or nearly touches) the forearm.


little finger extension.jpgHypermobile fingers can be bent back to 900.

hypermobile hands.jpgThe joints in the fingers and thumbs also bend backwards. 

The increased flexibility in the fingers make the hands less stable and the muscles have to work a lot harder when using the hands to grip, lift and manipulate objects.  

Sitting on floor_1.jpgThe hips, spine and ankles are also affected by increased laxity in the connective tissue.

The legs flop out sideways when sitting flat on the floor, especially when the child is very young.  

The child sits with a rounded back. 

The child may have flat feet, especially if the hip muscles are tight and the ankle muscles are weak. 

Loose joints but some tight muscles

sitting posture.jpg

Children with generalized joint hypermobility often have some tight muscles. This can be confusing. How to check for tight lower back and leg muscles

The muscles tightness develops because of the postures the hypermobile infant adopts when sitting on the floor. They often sit with the legs wide apart, sometimes with a flexed spine.

Read more: How joint hypermobility affects infant development


T sitting slumped.jpgThis leads to tightness in the muscles that cross over the back and sides of the hip and knee joints. As a result of the stiffness the child has difficulty sitting with the legs stretched forwards, may find sitting cross legged uncomfortable and has difficulty sitting erect on a chair. 

long sitting slumped.jpg

Infants with joint hypermobility are often late learning to sit, crawl and walk

Infants with joint hypermobility are often late learning to crawl and may not crawl at all, instead move around on their bottoms. They are slow to pull up into standing and often only learn to walk at about 18 months. 

Infants with joint hypermobility often lie, sit and stand with their hips wide apart. This leads to tightness in the hip muscles which has a long term impact on the child's motor control and is often the underlying reason for back and knee pain experienced by children with GJH. 

roan 10m prone 6.jpgRoan 12m standing low block 2_1.jpgroan 10m prone 1.jpg

Read more: How joint hypermobility affects an infant's development

Joint hypermobility and a very cautious/anxious nature

Children with joint hypermobility often have a very cautious/fearful  temperament style  which may lead to a raft of emotional and behavior difficulties which interfere with everyday school function. 

Highly cautious/fearful  children have a very active fear system. The regions of the brain that assess signals from within the body (such as body sensations) and information from the environment for the presence of potential threat or danger, are unusually alert and reactive. Things that are new, unfamiliar, different or difficult are interpreted as being threatening or dangerous. This creates a fear response and activates the body’s fear behaviors of fight, flee or freeze.

Cautious/fearful infants may be fussy, react strongly to any changes such as being undressed, are difficult to calm, react strongly to strangers or new situations. They also are very sensitive to being wet, hungry, or in discomfort.  These infants become easily over-aroused and distressed when there is a lot going on around them. As they get older they may develop a strong fear of strangers, cling to parents in new situations and develop separation anxiety. They are also less willing to take on hard work that is needed for learning to crawl and walk and may need extra encouragement to reach their milestones. 

As the cautious/fearful child gets a little older he/she may avoid activities that seem difficult, physically challenging or complex. Intense physical activity such as running or jumping creates strong sensations of effort within the body – and the child may interpret these as being threatening and so avoid physical activity.

Recognizing and understanding the impact  fearfulness and anxiety on behavior allows parents to implement strategies to help their children overcome their fears and learn to take on challenges. This particularly important for children with joint hypermobility who have to work harder to develop the muscle strength and stamina needed to counteract the effects of having hypermobile joints. 

Children with joint hypermobility often get a diagnosis of sensory processing disorder (SPD) and many of the issues related to having lax joints and a fearful nature are ascribed to sensory issues.  If your child has an SPD diagnosis and joint hypermobility it is important to ask the treating therapist to explain  how issues related to weakness, poor stamina, loss of flexibility in some muscles and issues related to anxiety and avoidant behavior  will be managed as part of the treatment plan. 


Low muscle tone and generalised joint hypermobility

Muscles are  held together by sheaths of connective tissue, called myofascia,  which gives them a small amount of natural stiffness. In people with joint hypermobility, these muscle sheaths are more pliable (have more give) than usual which means that the muscles have less inherent stiffness and are more easily stretched

When a muscle contracts it shortens and develops tension. This tension is transferred to muscle's tendons and then to the bones to produce movement.  In joint hypermobility the transfer of tension from the muscles the bone is less efficient. This means that the muscles have to work harder to produce movement and provide stability. 

The myofascial sheaths that hold the muscle together also give muscles the feeling of firmness when palpated. In joint hypermobility the laxity in the myofascial sheaths makes the muscles feel floppy.  

It is important to understand that the low tone which is seen in joint hypermobility is caused by the structure of the muscles themselves.

The only way to improve the tone in muscles with lax connective tissue is by strengthening the muscle which will increase the stiffness in the connective tissue that forms the tendons and myofascia. 

Hypermobile joints are easily injured

Children with joint hypermobility, muscle weakness and possibly poor coordination are more likely to complain of  pain and tiredness and are more likely to suffer from joint sprains, leg pain and night pain..

The laxity in the joint ligaments make them more vulnerable to injury.  Weak muscles are less able to able to protect the joints during during everyday activities that require a degree of fitness and agility.

Joint injury and pain can be reduced by strengthening weak muscles, increasing flexibility of tight muscles and improving coordination.  

Read more: How do I know if my child has weak muscles?

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What causes joint hypermobility?

The degree of compliance (stretchiness) in connective tissue is genetically determined. Between 10 and 20% of people have connective tissue that is more pliable ( less stiff)  than usual. So some degree of joint hypermobility can be viewed as part of the  normal variation in the structure of the connective tissue within the population.  

Children with generalised joint hypermobility will usually have a parent or other close relative with hypermobility.

Having hypermobile joints is often seen as a plus factor, particularly in gymnastics and ballet dancing.  To be a ballerina you need to have some degree of hypermobility. 

Hypermobility is also not always associated with movement difficulties. In my experience as a children's physiotherapist,  it is the combination of hypermobility, weakness, some muscle tightness and a very cautious nature that leads to movement difficulties.

How is joint hypermobility diagnosed?

The Beighton scale is most commonly used measure for diagnosing generalized joint hypermobility. This a nine point scale, measuring range of motion (ROM) at 8 joints plus the ability to put the hands down flat on the floor in standing.

The recommended cut-off point for a diagnosis of generalized joint hypermobility ranges between 5 and 7 for different clinicians and researchers.

little finger extension.jpgPassive dorsiflexion of the fifth metacarpophalangeal joint to < 90 degrees on the left and right hands (2 points)
wrist flexion.jpgPassive apposition of the thumb to the flexor side of the forearm, while shoulder is flexed 90 degrees, elbow is extended, and hand is pronated.  (Add one point for each wrist.) 
elbow extension.jpgPassive hyperextension of the elbow 100 or more. (Add one point for each arm.)
knee hyperextension supine_1.jpgPassive hyperextension of the knee 100 or more. (Add one point for each leg.)

hands to floor.jpgForward flexion of the trunk, with the knees straight, so that the hand palms rest easily on the floor


Handwriting and joint hypermobility 

There are several reasons why children with joint hypermobility have difficulties with handwriting, including: Hypermobile hand grip.jpg

  • poor control of the movements needed for handwriting: pencil grip and finger movements, shoulder movements and sitting posture 
  • poor control of the strokes needed for drawing and forming letters including poor ability to ability to preplan movements and draw /print  straight and curved lines without continuous visual guidance
  • poor development of motor plans for the letters allowing for fluent and fast writing ith minimal attention to letter formation

handwriting logo.jpeg_1.jpg

HWG Tools for Training Handwriting 

Why children with joint hypermobility have handwriting difficulties - and how parents and teachers can help a child to improve their handwriting skills 


Postural and movement difficulties children may have 

Children with GJH often have difficulties with a range of everyday, classroom and playground tasks and activities.  Poor general fitness along with muscle weakness and tightness in some muscles contribute to these difficulties especially if the child has a cautious nature and avoids tasks that require physical effort. 

Diffiuclties read more .jpeg

Generalised joint hypermobility and flat feet

J standing foot posture.jpgMany children with joint hypermobility (low muscle tone) have problems with flat feet. The inside border of the foot does not have a good arch and the heel bone is often angled outwards. 

In addition children with flat feet often stand with their feet turned out, and sometimes with the feet far apart. This tendency to stand with the feet turned out and far apart places abnormal stresses on the feet and hinders effective push-off for walking, jumping and running. 

Read more: Flat feet; not just a foot problem

Generalised joint hypermobility is associated with a range of physical difficulties 

The increased compliance in the connective tissue that causes hypermobility in joints also affects other parts of the body leading to a number of problems, including:

  • Bladder problems and bed-wetting  Focus on hypermobility copy.jpg
  • Bladder infections and vesicoureteral reflux
  • Low blood pressure 
  • Esophageal reflux
  • Chronic fatigue 
  • Chronic pain 
  • Idiopathic scoliosis - especially in girls where there is a family history of scoliosis 

Children with joint hypermobility often complain of leg and back pain

The combination of loose joint structures (ligaments and capsule)  along with muscle weakness and some tight muscles causes abnormal stresses on knee joints which in turn leads to knee pain after exercise or at night. More about leg pain

Children with joint hypermobility may also experience back pain due to poor posture and muscle weakness.

New  Graded  strength exercises for children who complain of leg pain

How to help your child

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