My Explanation

Cerebral palsy (CP) is an umbrella term for a group of disorders affecting body movement, balance, and posture. Loosely translated, cerebral palsy means “brain paralysis.” Cerebral palsy is caused by abnormal development or damage in one or more parts of the brain that control muscle tone and motor activity (movement). The resulting impairments first appear early in life, usually in infancy or early childhood. Infants with cerebral palsy are usually slow to reach developmental milestones such as rolling over, sitting, crawling, and walking.

Common to all individuals with cerebral palsy is difficulty controlling and coordinating muscles. This makes even very simple movements difficult.

• Cerebral palsy may involve muscle stiffness (spasticity), poor muscle tone, uncontrolled movements, and problems with posture, balance, coordination, walking, speech, swallowing, and many other functions.
  
  
• Mental retardation, seizures, breathing problems, learning disabilities, bladder and bowel control problems, skeletal deformities, eating difficulties, dental problems, digestive problems, and hearing and vision problems are often linked to cerebral palsy.
  
  
• The severity of these problems varies widely, from very mild and subtle to very profound.
  
  
• Although the magnitude of the problems may wax and wane over time, the condition does not get worse over time.

Types of cerebral palsy are as follows:

• Spastic (pyramidal): Increased muscle tone is the defining characteristic of this type. The muscles are stiff (spastic), and movements are jerky or awkward. This type is classified by which part of the body is affected: diplegia (both legs), hemiplegia (one side of the body), or quadriplegia (the entire body). This is the most common type of CP, accounting for about 70-80% of cases.
  
  
• Dyskinetic (extrapyramidal): This includes types that affect coordination of movements. There are 2 subtypes.
  
  

  • Athetoid: The person has uncontrolled movements that are slow and writhing. The movements can affect any part of the body, including the face, mouth, and tongue. About 10-20% of cerebral palsy cases are of this type.
    

  • Ataxic: This type affects balance and coordination. Depth perception is usually affected. If the person can walk, the gait is probably unsteady. He or she has difficulty with movements that are quick or require a great deal of control, such as writing. About 5-10% of cases of cerebral palsy are of this type.
    
    
• Mixed: This is a mixture of different types of cerebral palsy. A common combination is spastic and athetoid.

Many individuals with cerebral palsy have normal or above average intelligence. Their ability to express their intelligence may be limited by difficulties in communicating. All children with cerebral palsy, regardless of intelligence level, are able to improve their abilities substantially with appropriate interventions. Most children with cerebral palsy require significant medical and physical care, including physical, occupational, and speech/swallowing therapy.

So where do I and fellow SDR candidates fall into these categories? In order to be a candidate for SDR as an adult patient, Dr. Park has a clearly defined criteria. Only adults who have "Mild" CP of the spastic diplegia classification are considered for surgery. The term "Mild" is deceiving. It is true that compared to other types and intensities of CP, we patients are on the "milder" side of symptoms and tend to be high functioning both physically and cognitively, however, the toll that muscle spasticity takes on our bodies over time is certainly not mild in the long run. Because muscles in the lower extremeties (hamstrings, calfs, gluteus, quads, etc.) are spastic, they are unable to stretch. Therefore, they are difficult to strengthen. Also, due to their tightness (spasticity), they cause unnatural and unbalanced forces on the skeletel system, which in turn results in pain and degeneration of ligaments, tendons, and overall muscular weakness. This weakness then causes other "normal" muscles to work "overtime", performing functions they are not meant to do, which results in muscle fatigue and recurrent strains, sprains, and skeletal changes in response to the overall compromise of the muscular system.

The command to tense, or increase muscle tone, goes to the spinal cord via nerves from the muscle itself. Since these nerves tell the spinal cord just how much tone the muscle has, they are called "sensory nerve fibers." The command to be flexible, or reduce muscle tone, comes to the spinal cord from nerves in the brain. These two commands must be well coordinated in the spinal cord for muscles to work smoothly and easily while maintaining strength.

In a person with CP, damage to the brain has occurred. For reasons that are still unclear, the damage tends to be in the area of the brain that controls muscle tone and movement of the arms and legs. The brain of the individual with CP is therefore unable to influence the amount of flexibility a muscle should have. The command from the muscle itself dominates the spinal cord and, as a result, the muscle is too tense, or spastic.

As you may or may not know, muscles work in pairs and are named agonists and antagonists. In muscle spasticicty, the tighter muscle disturbs the balance of this muscular relationship, causing the tighter muscle to effectively, "turn off" it's related mate. Therefore, the "off" muscle is not able to be accessed by the body, it cannot be easily strengthened, and the function of that muscle is compensated for by another, causing the chain reaction mentioned earlier of muscle fatigue, etc. One of the most common results of this phenomenon is low back pain for obvious reasons.

Balance and coordination is also negatively affected by CP due to the inability to access and properly use muscles that contribute to balance.

Patients spend their whole lives stretching daily to try to keep muscles as flexible and strong as possible. However, the effects of stretching are very short-lived as no permanent improvement is really ever achieved. Normal-bodied people obviously get stiffer, tighter, and less flexible as they age. For the CP patient, this process becomes one that progresses exponentially, as we already have quite a "head start" on our limited flexibility to begin with. Therefore, a a 30 year old body may very well feel and have the structural deterioration of one that is 40 years. CP patients have to work harder and use far more energy to do daily tasks and physical activities then normal-bodied people. Therefore again, our stamina decreases quicker than most in activities such as walking, running, climbing stairs, etc.

The beauty of the SDR surgery is that it attacks the core problem directly, muscle spasticity. With SDR surgery, muscle spasticity is greatly reduced, and in some cases, eliminated altogether to a normal level!

Now that you have a background of the CP condition, my next entry will be to explain the SDR surgery in detail!