The “ideal” candidate for SDR
This is the second in a series of blog posts on selective dorsal rhizotomy (SDR) in adulthood by guest author, Lily Collison.
Selection criteria for SDR differs between institutions. Characteristics of the “ideal” candidate for SDR at Gillette include:
- Aged 4 to 7 years.
- GMFCS level I–III.
- Primarily spasticity (as opposed to dystonia) that interferes with function.
- Preterm birth history or injury in the late second or early third trimester of pregnancy.
- Periventricular leukomalacia (PVL) confirmed by neuroimaging. (PVL is the brain injury that commonly results in the motor problems seen in spastic diplegia.)
- Energy-inefficient gait.
- Satisfactory muscle strength, generally defined as antigravity muscle strength at the hips and knees.
- Fair or good selective motor control at the hips and knees. This means being able to partially isolate joint movement (not moving the joint in a complete pattern). This requires sufficient strength and motor control, i.e., not being reliant on increased spasticity for stability or movement.
- Good ability to cooperate with rehabilitation.
Other than specific brain injury and age, Tommy met the selection criteria above. Tommy’s primary tone problem is spasticity (minimal dystonia) and the degree of spasticity was problematic for him. Though he does not have the classic brain injury (PVL), it was felt that his brain injury would behave similar to one, in causing spasticity. It would have been far more ideal had Tommy undergone SDR as a child. Tommy missed the opportunity to have it then, as we lived in Ireland and by the time I learned of SDR, he was already aged nine and needed orthopedic surgery to address the muscle and bone problems that had already developed. (Today, Irish children who meet defined selection criteria are able to access SDR in the United Kingdom.) SDR in childhood is better than in adulthood because the older the person, the longer they have been experiencing the negative effects of spasticity on their muscles. SDR in childhood is also better because rehabilitation after surgery (of any type) is more prolonged in adults than in children–adults heal more slowly than children.
Despite the above SDR in adulthood is still beneficial–it reduces the negative effects of spasticity on muscles over a person’s lifetime. Tommy is only 26 with a normal life expectancy. Apart from preserving his muscles, Tommy’s walking will hopefully become more energy efficient, which should translate into greater endurance in walking. Before SDR, his energy consumption in walking was 2.4 times normal. By one year post-op, it is hoped that this will have improved somewhat–it still won’t be normal (nor near normal) but any improvement is valuable. Although SDR is adulthood is beneficial, it is a big consideration. The most difficult short term challenges (i.e., following the surgery and during early rehabilitation) for independent adults following this type of surgery include loss of independence, loss of ability to care for others, and loss of income.
In the next post I’ll address surgical decision-making.
Lily Collison is author of Spastic Diplegia–Bilateral Cerebral Palsy