Causes Of Baby Not Bearing Weight On Legs (Developmental Delays To Watch Out For)

Suppose your baby is delayed in bearing weights on their legs which hinders a developmental milestone of crawling or walking. In that case, it could be that they’re delayed in reaching there or suffering from a medical condition. These issues include down syndrome, vitamin D deficiency, cerebral palsy, congenital orthopedic defects, muscular dystrophy, or myasthenia gravis. These conditions affect leg muscles in various ways, making it difficult to strengthen them and start walking. Each issue has its treatments available and what you need to do is keep an eye on your baby’s developmental milestones along with their health condition. 

Every baby has milestones to reach in their life growing up, such as when they start crawling, weaning, trying to stand up, walking, etc. Each of these milestones is vital in showing that your baby is developing normally. 

Parents become worried when their child can’t achieve these milestones or isn’t developing properly at a certain age. Although delays in achieving any milestone are entirely normal, sometimes the causes could be severe. 

Not being able to bear weight on legs by a certain age is one issue many parents might be worried about. And it can lead to problems with not being able to stand up or start walking. Let’s see the possible causes behind a baby’s inability to gain weight in the legs and how it affects them. 

Baby not bearing weight on legs

Your baby’s going to achieve all these milestones as they grow, but every baby takes their own sweet time to do so, and there’s nothing wrong with it as long as you’re seeing progress in their milestones. Sometimes the next milestone doesn’t arrive weeks or even a few months after the typical timing. 

Some babies start gaining strength in their legs sooner and might begin crawling or walking earlier, and some babies take time to achieve the same. This is mainly called a developmental delay.

In such cases, the pediatrician will check up on your baby and see what other milestones they have reached and how long it took them to get there.

Developmental delays to watch out for

While the reasons behind why your baby isn’t able to bear weight on their legs are extensive, you won’t be able to diagnose your baby quickly if it’s a complicated medical issue.

So, there’s a need for you to be alert and look at additional symptoms along with no weight-bearing in your legs to determine if something is wrong.

You shouldn’t be overly stressed if there’s a developmental delay because, frankly, there’s no hard or defined rule about it and your baby just needs to accomplish everything in a specified time.

Notice if there’re multiple delays like:

  • Not bearing weight in legs
  • Rolling over
  • Delay in walking or crawling
  • Sitting up (by 9 months)
  • Babble
  • Laugh
  • Responding to games such as peekaboo
  • Responding to their environment
  • Seeking your attention in any way possible
  • Stiff or tight leg muscles

Possible causes of baby not bearing weight in legs

1. Down syndrome 

A cute infant boy with down syndrome is laying on his tummy and smiling

Down syndrome is one of the most common genetic disorders and affects about one baby every 700 births. Though children with this syndrome may have varying developmental delays and other medical problems, they might not seem like it in the initial stage. 

The severity of this syndrome differs from child to child, and they’ll eventually reach their milestones but may be slower than other babies in activities such as turning over, sitting, standing, walking, and other physical activities.

Down syndrome’s most common musculoskeletal effects include weak muscle tone (hypotonia) and ligaments that are too loose (ligament laxity). This leads to excessive joint flexibility. 

There’s a reduced muscle strength witnessed in children with down syndrome. Motor function in this syndrome is characterized by hypotonia and hyper flexibility, resulting in an increased risk of joint dislocation and retarded motor skills. 

  • Hypotonia (decreased muscle tone) has a negative effect on the proprioceptive feedback from muscle and joint sensory structures. It can have a detrimental impact on the efficiency of co-contractions and postural reactions. 
  • Hyper flexibility is another thing witnessed in children with down syndrome, with more joint flexibility than the average. This increased joint mobility may also contribute to a lack of posture control. 

Isolated musculoskeletal pain in the absence of other signs or symptoms is rarely a presenting symptom in children with chronic arthritis. 

2. Vitamin D deficiency

Vitamin D is quite important for babies growing up, which is why so much attention to their milk needs and getting out in the sun is pushed forward to get their daily dose of this essential vitamin.

This vitamin is essential for healthy growth and development and helps your tiny one build strong bones and teeth. One possible reason for your baby not bearing weight in their legs could be a growth issue caused by vitamin D deficiency.

Receiving plenty of sunlight, drinking milk, having healthy leafy foods, and vitamin supplements are ways to ensure their vitamin D deficiency can be diminished. 

Signs of vitamin D deficiency include:

  • A severe vitamin D deficiency is noticeable when the baby has soft or weak bones, which can easily curve, known as rickets. 
  • If you notice a tooth delay when your baby should be sprouting their temporary teeth, they aren’t receiving enough Vitamin D. This is an important developmental milestone.
  • You’ll witness stunted growth and developmental delay in your little one. Since vitamin D is an essential vitamin development of their bones, it’s likely their bone growth will be negatively impacted.
  • Most babies will experience bouts of cold and flu during winter months, and a lack of vitamin D will put them in a more severe position elongating their symptoms even more. They’ll be more prone to developing respiratory infections.
  • Another sign of vitamin D deficiency is a fussy baby. According to the American Academy of Family Physicians, irritability is one of the symptoms that’s often associated with a vitamin D deficiency in babies. 

Talk to your health care provider about the steps you can take to improve your baby’s vitamin D intake. 

3. Cerebral Palsy

Cerebral palsy affects children in numerous physical and neurological ways. But the condition and severity of movements issues in children depend on the type of brain damage a child suffers. Many signs aren’t even diagnosed until a baby reaches the stage of a toddler since these signs and symptoms might be difficult to identify. 

Some signs and symptoms to help identify if your infant has cerebral palsy:

  • Abnormal muscle tone
  • Crossed or stiffened legs when being picked up
  • Delays in sitting, crawling, rolling over, and walking
  • Difficulty grasping objects or clapping their hands
  • Excessive drooling
  • Inability to lift their head
  • Overextended back and/or neck when being picked up
  • Tight muscles or stiffness in joints (spasticity)

Cerebral palsy is often diagnosed in toddlers since their symptoms start becoming noticeable such as:

  • Abnormal posture
  • Crawling in a lopsided manner
  • Difficulty with fine motor skills such as eating, brushing teeth, or coloring
  • Hearing loss or blindness
  • Hopping on their knees when trying to walk
  • Inability to stand
  • Uncontrollable muscle movement
  • Scooting around on their buttocks
  • Speech problems
  • Stiff muscles, joints, or tendons

There could be various causes behind why your baby might show signs and symptoms of cerebral palsy, but you can reduce its risk during your pregnancy by:

  • Making sure you’re vaccinated
  • Taking care of yourself
  • Seek healthy and continuous prenatal care
  • Avoid alcohol, tobacco, and illegal drugs

There’s no cure for cerebral palsy, but various treatment options are available to help improve your child’s daily functioning. But an early diagnosis can help immensely, and treatment options include medications, therapies, surgical procedures, and other treatments. 

4. Congenital orthopedic defects

Orthopedic congenital disabilities include a wide range of conditions affecting a baby’s bones and muscles, tendons, and ligaments that connect them. These conditions occur while the baby is still developing in the uterus.

While some of these defects might heal on their own, others need help in treating them, such as:

  • Difficulty walking and running
  • Bone destruction
  • Deformities in bones, muscles, and joints of the limb
  • Arthritis in later life

Symptoms and signs to watch out for include:

  • Visible problems with a baby’s legs, feet, arms, or hands
  • Spine twisting, curvature, or bowing
  • Bones that break easily
  • Reduced movement in infants or difficulty walking in children 

Various congenital disabilities result from development problems in babies, which may vary from mild to life-threatening, including:

  • Clubfoot
  • Developmental dysplasia of the hip
  • Metatarsus adductus
  • Spine deformities including scoliosis and kyphosis
  • Osteogenesis imperfects
  • Muscular dystrophy
  • Limb defects
  • Bone infections

Depending on the kind of congenital disability, the pediatrician may recommend different types of tests to diagnose the condition and suggest treatment options that include:

  • Braces, splints, or casts to properly align bones and joints
  • Physical therapy to improve strength and range of motion
  • Occupational therapy to help build skills such as eating, getting dressed, and walking
  • Surgery to adjust bones, muscles, and tendons in severe conditions

5. Muscular dystrophy

A toddler with muscular dystrophy is doing exercises with her physical therapist

Muscular dystrophy is a genetic disorder of the muscles which causes muscles in the body to become very weak. The muscles break down and are replaced with fatty deposits over time. One reason behind why your baby isn’t gaining weight or has started to crawl and walk might be because of this.

It’s usually diagnosed in children between 3 and 6 years of age. Early signs of the illness include a delay in walking, difficulty rising from a sitting or lying position, and frequent falling, with weakness that affects the shoulder and pelvic muscle as one of the initial symptoms. 

Here are some common symptoms:

  • Clumsy movement
  • Difficulty climbing stairs
  • Frequently trips and falls
  • Unable to jump or hop normally
  • Tiptoe walking
  • Leg pain
  • Facial weakness
  • Inability to close eyes or whistle
  • Shoulder and arm weakness

In one type of Duchenne muscular dystrophy, find it very hard to get up from a sitting or lying position on the floor. They first pull up to their hands and knees, and the child walks their hands up their legs to brace themselves as they rise to a standing position. 

For children with DMD, you’ll notice them having large calves due to the large amounts of fatty deposits replacing muscle. But the signs and symptoms of this condition might resemble other conditions, so proper diagnosis is required. 

Treatment depends on many factors such as the type and extent of the condition, child’s age, overall health and medical history, child’s tolerance to specific medications, procedures, or therapies, expectations for the course of the condition, and your opinion or preference.

Non-surgical treatments include:

  • Physical therapy
  • Positioning aids are used to help the child sit, lie, or stand
  • Braces and splints used to prevent deformity, promote support, or provide protection
  • Medications
  • Nutritional counseling
  • Psychological counseling

There’s no particular medication or surgery which can completely cure muscular dystrophy or stop the muscles from weakening, but with the proper treatment, the condition can be prevented from becoming worse or severe. 

6. Myasthenia Gravis

Myasthenia gravis (MG) is a disorder that causes muscle weakness around the body. This disorder is caused because antibodies destroy some places where nerves and muscles meet. MG affects the body’s voluntary muscles, affecting parts including eyes, mouth, throat, arms, and legs. 

Types of MG which affects children are:

  • Transient neonatal MG is a temporary form that occurs in babies born to mothers with MG and lasts only for a short time.
  • Juvenile MG is an autoimmune disorder occurring in white teen girls and is a lifelong condition that might be curable by surgery.
  • Congenital MG is a very rare form and isn’t an autoimmune disorder. Symptoms include overall weakness in the arms and legs and delayed motor skills.

Treatment depends on the child’s symptoms, age, general health, the severity of the condition, and type of MG.


How can I help my baby bear weight on his legs?

There are various reasons behind your baby not being able to bear weight on their legs, and some of them could be medical reasons or an average delay in achieving this milestone.

If it’s not because of a medical reason, there’re several things you can do to help your baby start walking by strengthening their legs:

– Exercising or any physical activity. Support them as they’re trying to pull themselves up and start to walk.
– Bouncing up and down is normal for babies, and they mostly love it. This helps build the muscles in their legs to allow them to walk later on. You can play music to help them be more interested in this activity.
– Giving them free space is just the thing your baby needs to start making efforts into standing up and start walking.
– You can use bright toys or noise to attract them to walk to you from one point.
– Play with your baby as often as possible and let them play with other babies their age.
– Positive reinforcements such as getting excited, clapping, and being overjoyed when they achieve a milestone or when they’re trying to use their legs to stand up or walk can be very encouraging.

What causes a delay in child walking?

Every child has different timing to start walking, and there should be no comparison. But by the age of 18 months, your child should start walking or at least attempt to. If they’re not walking, this delay could be caused by various developmental issues.

These could be foot or leg problems such as developmental hip dysplasia, rickets (softening or weakening of bones), or conditions affecting muscle tones like cerebral palsy and muscular dystrophy.

You should keep an eye on your baby’s movement and how much time they’re taking in achieving each of their milestones.

Check in with your doctor if there seems to be an issue with their other developmental milestones or they are limp, and their legs appear weak or uneven. 

How do you know if your baby is developmentally delayed?

Signs of a physical developmental or early motor delay:

– Delayed rolling over, sitting, or walking
– Poor head and neck control
– Muscle stiffness or floppiness
– Speech delay
– Swallowing difficulty
– Body posture that’s limp or awkward
– Clumsiness
– Muscle spasms 

What are the 5 developmental disabilities?

A doctor or a pediatrician can help in identifying these developmental disabilities.

There are five types of developmental disabilities, including autism spectrum disorder (ASD), cerebral palsy (CP), intellectual disability (ID), attention deficit hyperactivity disorder (ADHD), and learning disabilities. 

To summarize

It can be stressful whenever your baby isn’t reaching a developmental milestone they should have or isn’t showing healthy signs of weight gain in their legs. This makes you wonder if they’re just delayed or is there a medical condition behind this issue of theirs.

The best thing you can do is watch your little one and see what they have achieved or haven’t achieved by a certain age. If you see additional symptoms or delay in mental or physical growth, then it might be the right time to discuss it with your pediatrician along with your family history.

There’s no harm in getting a professional opinion, but also, you don’t need to worry so much and help your baby by trying to strengthen their leg muscles. 

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As a writer for 1happykiddo, Saumya wants to help new parents and older siblings help raise the newest member added to the family. Her parenting tips come from her experience of being 15 years older than her youngest sibling. When not writing, you can find her reading novels, traveling, and cooking nutritious meals.

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