Biplegia is a form of cerebral palsy characterized by motor dysfunction that primarily impacts the legs. The condition originates from damage to the developing brain, not from problems within the muscles or nerves. While the legs are the most significantly affected, some individuals may also experience milder involvement in their arms and hands. The term is used interchangeably with spastic diplegia, a subtype of spastic cerebral palsy.
Symptoms and Physical Manifestations
The most prominent feature of biplegia is spasticity, a state of increased muscle tone that causes stiffness, particularly in the lower body. This heightened tone leads to a distinctive walking pattern known as a “scissoring” gait. In this gait, the tightness of hip and leg muscles causes the knees and thighs to pull together, turn inward, and cross over one another while walking.
Beyond the characteristic gait, individuals with biplegia contend with other physical challenges. Difficulties with balance and coordination are common, affecting the ability to stand, walk, and perform other motor tasks. Another observable sign is toe walking, where the child walks on the balls of their feet because of tight calf muscles.
While many children with the condition are able to walk, it is often delayed until they are between two and four years old. The severity of these symptoms can vary, with some individuals walking independently and others requiring mobility aids like crutches or walkers.
Causes and Risk Factors
Biplegia is the result of an injury to the brain’s motor cortex, the region responsible for planning and executing voluntary movements. This brain damage most often occurs before, during, or shortly after birth. The cause is frequently linked to an abnormal development of the brain’s white matter, the network of nerve fibers that facilitates communication between brain regions.
Events that disrupt normal brain development can be grouped into distinct periods. Prenatal factors, occurring before birth, include maternal infections, exposure to toxins, or certain genetic conditions. The most significant risk factors are premature birth and low birth weight, as infants born early are more susceptible to brain injury.
Perinatal factors, which occur during the birthing process, can also contribute. A lack of oxygen to the infant’s brain (hypoxia) or complications with the umbilical cord can lead to brain damage. Postnatal causes, happening shortly after birth, may include severe jaundice, brain infections like meningitis, or head trauma. In many cases, a combination of multiple risk factors is involved.
The Diagnostic Process
The journey to a biplegia diagnosis often begins with concerns about a child’s development. An early indicator is the failure to meet age-appropriate motor milestones, such as rolling over, sitting, or crawling. These initial observations typically prompt a more thorough evaluation by healthcare professionals.
A detailed physical and neurological examination is a part of the diagnostic process. During this assessment, a specialist evaluates the child’s muscle tone for spasticity, checks reflexes, and observes movement patterns and posture. The presence of exaggerated reflexes and abnormal muscle tone are significant indicators. The doctor will also take a medical history, inquiring about the pregnancy, birth, and the child’s health in early infancy.
To confirm the diagnosis and identify the cause, neuroimaging tests are used to visualize the brain. A Magnetic Resonance Imaging (MRI) scan is effective as it provides detailed images of the brain’s structure and can reveal areas of damage consistent with cerebral palsy. A Computed Tomography (CT) scan may also be used. In some cases, an electroencephalogram (EEG) might be performed if seizures are a concern.
Therapeutic Management Strategies
Management of biplegia involves a multi-faceted approach aimed at improving function and quality of life, as the underlying brain injury does not worsen. Physical therapy is a component of treatment. Therapists guide patients through exercises designed to stretch spastic muscles, improve flexibility, build strength, and enhance balance and coordination. A focus is often placed on gait training to improve walking patterns.
Occupational therapy helps individuals gain independence in daily life. Therapists focus on fine motor skills and adaptive strategies for activities such as dressing, eating, and personal hygiene. They may also recommend adaptive equipment, like specialized utensils or dressing aids, to make these tasks easier. This therapy helps children participate more fully in school and play activities.
To manage muscle stiffness, various medical interventions may be utilized. Oral muscle relaxant medications like baclofen can help reduce overall spasticity and discomfort. For more targeted relief, injections of botulinum toxin (Botox) can be administered into spastic muscles to temporarily relax them, which can improve range of motion and make stretching more effective.
Orthotic devices are commonly prescribed to support proper joint alignment and assist with walking. Ankle-foot orthoses (AFOs) are braces worn on the lower leg and foot to help control ankle position, prevent toe-walking, and provide a more stable base for standing and walking. These devices are custom-fitted and are an integral part of managing gait abnormalities.
In some instances where severe spasticity significantly impacts mobility and does not respond to other treatments, surgical options may be considered. Orthopedic surgery can lengthen tightened muscles or correct bone alignment issues. Another procedure, called selective dorsal rhizotomy (SDR), involves cutting specific nerve fibers in the spinal cord to permanently reduce spasticity in the legs.