The earliest signs of cerebral palsy usually appear in the first six months of life as differences in muscle tone, posture, and movement. Some babies feel unusually stiff when you pick them up, while others feel floppy and limp. Because cerebral palsy results from brain differences that occur before, during, or shortly after birth, the signs are present from the start, but they often become easier to recognize as a child grows and misses expected developmental milestones like sitting, crawling, or walking.
Signs in Babies Under 6 Months
The first clues tend to show up during everyday handling. A baby with cerebral palsy may not be able to hold up their head when lifted from lying on their back. When you pick them up, their legs may stiffen and cross like scissors instead of bending naturally. Some babies arch their back and neck so forcefully it feels like they’re constantly pushing away from you.
Muscle tone is one of the most telling early indicators, and it shows up in two opposite ways. Some infants have hypertonia, where the muscles are persistently stiff and the limbs resist being moved. Others have hypotonia, where the muscles feel loose and floppy, making the baby seem like a ragdoll when held. Both patterns reflect how the brain is communicating (or failing to communicate) with the muscles, and either one warrants attention.
Persistent Primitive Reflexes
All newborns are born with automatic reflexes. The Moro reflex, that startled arms-out reaction, typically fades by about four to six months. The asymmetric tonic neck reflex, where turning the head causes the arm on that side to extend, usually disappears around the same time. In babies with cerebral palsy, these reflexes can persist well beyond the age when they should have integrated. Their presence past six months is a red flag that the brain’s motor pathways aren’t maturing on schedule.
Missed Milestones by Age
Developmental milestones offer the clearest timeline for spotting delays. Not every late milestone means cerebral palsy, but a pattern of missed targets across motor and communication skills is significant.
- By 9 months: Trouble sitting up independently, not babbling, or showing little interest in social interaction.
- By 12 months: No response to their name, no pointing or waving.
- By 18 months: Difficulty walking, fewer than six words, or trouble imitating sounds and gestures.
- By 2 years: Not combining two words into phrases or struggling to follow simple instructions.
Motor delays tend to be the most visible piece. A child who isn’t sitting by 9 months or walking by 18 months, or who seems persistently clumsy compared to peers, is showing signs that should be discussed with a pediatrician.
Early Hand Preference
Most children don’t develop a dominant hand until around 18 months. If a baby strongly favors one hand before that age, consistently reaching, grasping, and playing with only one side, it can indicate hemiplegic cerebral palsy, a form that affects one side of the body. You might also notice the child dragging one leg while crawling or always rolling to the same side. These asymmetries are easy to dismiss as quirks, but they’re worth flagging early.
Walking Patterns in Toddlers
Once a child starts walking, the way they walk provides important information. Children with cerebral palsy often develop distinctive gait patterns that reflect which muscles are too tight or too weak.
Toe walking is one of the most recognized signs. In “true equinus,” the ankle stays pointed downward throughout the step while the hips and knees remain straight, so the child walks on the balls of their feet. A more complex pattern called “jump gait” adds bending at the knees and hips along with toe walking, creating a bouncy, crouched posture with an exaggerated curve in the lower back.
Some children appear to toe-walk even though their ankles have normal range of motion. Their hips and knees are excessively bent, pushing them up onto their toes as a compensation. On the other end, “crouch gait” looks like the child is always in a partial squat, with deep bending at the ankles, knees, and hips. Any of these patterns that persist beyond the wobbly early months of learning to walk deserve evaluation.
How Signs Differ by Type
Cerebral palsy isn’t one condition. It’s a group of movement disorders, and the signs look different depending on which type a child has.
Spastic cerebral palsy is the most common form. The hallmark is stiff muscles that produce jerky or repetitive movements. A child’s arms or legs may resist being straightened, and movements look effortful rather than fluid. This type accounts for the majority of cases.
Dyskinetic cerebral palsy produces slow, uncontrollable writhing movements in the hands, feet, arms, or legs. The face and tongue muscles can also be overactive, leading to drooling or involuntary facial expressions. Children with this type often struggle to sit upright or walk because their muscle activity is unpredictable, fluctuating between too loose and too tight.
Ataxic cerebral palsy primarily affects balance and coordination. Children walk with an unsteady, wide-based gait and have difficulty with precise movements like writing, buttoning a shirt, or reaching for objects accurately. Depth perception can also be impaired.
Some children have a mix of these types, showing stiffness in one area and uncontrolled movements in another.
Subtle Signs and Late Diagnosis
Mild cerebral palsy can go undiagnosed for years. When only one side of the body is affected, or when the muscle tone differences are slight, the signs may not become obvious until a child faces more demanding physical tasks in preschool or early school years. Favoring one side of the body, slight clumsiness, or difficulty with fine motor tasks like using scissors can all be subtle presentations.
The brain condition that causes cerebral palsy doesn’t change over time, and symptoms don’t worsen with age. But as a child grows, the gap between their abilities and those of their peers can widen, making signs that were easy to overlook in infancy more apparent. A two-year-old who is “just a little behind” may look more noticeably different by age four, not because the condition progressed, but because the demands on their motor system increased.
Early identification matters because the brain is most adaptable in the first few years of life. Therapies started during that window of high brain plasticity tend to produce the greatest improvements in movement, coordination, and independence.