Introduction
Cerebral palsy is a complex disability and diagnosis is not always an easy process. Doctors may suspect cerebral palsy if a baby has slow motor development (does not reach movement milestones), has tight or floppy muscle tone, or displays unusual postures.
When is Cerebral Palsy Diagnosed?
The time at which a child is diagnosed with cerebral palsy varies. If a baby is very premature, early scans (such as an MRI - magnetic resonance imaging) might show that they have an injury to the brain, but at that stage it is often too early to predict the impact.
The General Movements Assessment can be conducted from birth until 3 months of age. It has been shown to be a strong predictor of cerebral palsy, particularly when certain changes to the brain are seen on an MRI. If the result is that a baby is "at risk of cerebral palsy", then intervention can start as early as one month. The General Movements Assessment cannot, however, predict the severity of cerebral palsy.
Most children with cerebral palsy are not born prematurely. Most are born at full term and it is not until they do not meet the usual infant milestones that any form of disability is considered.
Milestones
All babies develop at different rates, but they generally reach a set of milestones around 3, 6, 9 and 12 months of age.
These might include:
- holding own head up when lying on their stomach or in a supported sitting position
- sitting and rolling over by 6 months
- walking by 12-18 months
- speaking in simple sentences by 24 months.
In NSW, questions relating to these milestones are described in the Personal Health Record book (Blue Book) provided to families when their child is born. Parents are usually the ones to notice that their child is not reaching these milestones and may alert their early childhood nurse, general practitioner or paediatrician
How Do Doctors Diagnose Cerebral Palsy?
Cerebral palsy is a condition that:
- is permanent but not unchanging
- involves a disorder of movement and/or posture and of motor function
- is due to a non-progressive lesion or abnormality which has originated in the immature brain.
In order to make a formal diagnosis of cerebral palsy, doctors will take a complete medical history and carefully examine the child. They will pay special attention to the child’s movements – both their voluntary movements as well as their muscle tone. Some children may have very relaxed, floppy muscles, while others have stiff, tight muscles. Doctors will also look for any unusual postures or if the child favours one side over the other.
Scans such as MRI (magnetic resonance imaging) or CT (computed tomography) may be ordered by the doctor.
One of the frustrations for parents is that sometimes a diagnosis can take a long time, with repeated tests and visits to specialists. This may be because the child has a mild form of cerebral palsy, but it could also be because the doctor needs to make sure it is not another type of movement disorder that may be progressive (get worse over time).
