Cerebral palsy is not a single disorder but rather an umbrella term used to describe a broad range of neurological abnormalities, affecting movement and posture that first occur in the fetal or infant brain. Importantly, these movement disorders may be accompanied by disturbances in sensation, cognition, communication and behavior. While the phrase “cerebral palsy” is not new and is certainly widely recognized, the precise definition of the term still remains unclear. In fact, medical organizations have sought to more precisely define the term “cerebral palsy” as recently as within the last five years. While the proposed definitions are complex (as they necessarily must be in order to be precise), they do encompass the illness’ key features.
Classifications of Cerebral Palsy
While this broad definition is useful in some contexts, it is sometimes more useful to discuss the specific types of cerebral palsy. The main way that physicians classify cerebral palsy is the way in which the child appears at rest and while in motion. From these observations, most patients are diagnosed with either spastic or dyskinetic cerebral palsy, or infrequently, both.
Spastic Cerebral Palsy
In spastic cerebral palsy (also called pyramidal), the patient has increased muscle tone in the affected areas of the body. In real terms, this means that anyone trying to move the patient’s limbs would find it difficult, even if the child was not actively resisting motion. Likewise, the child’s reflexes would be very robust. Consider when a doctor taps a patient’s knee with a hammer and the lower leg extends involuntarily. In people with cerebral palsy, that “kick” is quite large. In fact, when reflexes are tested, the muscle may activate more than once, causing several kicks, which is an event known as clonus.
Dyskinetic Cerebral Palsy
As the name implies, dyskineticcerebral palsy is condition that causes disordered movement. In this type, the patient displays abnormal movements outside of their direct control (involuntary). These abnormal movements may affect one or more limbs and/or the muscles of the face. Dyskineticcerebral palsy (also called extrapyramidal) is sometimes further subdivided into choreoathetoid and ataxic types. The former describes irregular, dancelike movements while the latter refers to a general lack of movement, almost like a paralysis.
Location Used to Classify Cerebral Palsy
- Cerebral palsy may be further classified according to the affected limbs using names such as hemiplegia, quadriplegia, diplegia, and monoplegia.
- Hemiplegia – Affects one side of the body; usually the upper limb more than the lower
- Quadriplegia– All four limbs are affected including the torso
- Diplegia– Affects either the upper or lower half of the body; usually lower half
- Monoplegia– Affects one limb
Medical researchers have proposed other ways to classify patients with cerebral palsy. In addition to broad categories (spastic and dyskinetic) and anatomical groupings, precise diagnosis may include accompanying impairments, radiological findings, and cause/timing; however these latter groupings are contentious.
Limitations of Classification
At times a broad definition of cerebral palsy is useful and at others more focused classification helps. Nevertheless it is important to recognize that each person with cerebral palsy has a unique set of difficulties and needs, some that extend beyond the physical. A comprehensive classification system should encompass these diverse needs.