Editorial
Selective Dorsal Rhizotomy – Long Term Follow-up
Tae Sung Park, M.D.1
and
Jack R. Engsberg, Ph.D.2
1 Center for Cerebral Palsy Spasticity, St. Louis Children's Hospital and
Department of Neurological Surgery,
2 Human Performance Laboratory, Program in Occupational Therapy,
Washington University School of Medicine, St. Louis, Missouri
Correspondence should be sent to:
Tae Sung Park, M.D.
Department of Neurological Surgery
Washington University School of Medicine
Box 8057, 660 South Euclid Avenue
St. Louis, MO 63110
314-977-8532
314-977-8513 (fax)
[email protected]
In this issue of the Journal of Neurosurgery: Pediatrics, Langerak and
colleagues report on the gait of a group of subjects with spastic diplegia
cerebral palsy twenty years after their selective dorsal rhizotomy (SDR).
In total, the work includes results from preoperative, 1, 3, 10 and 20
years, postoperative.
This body of work seems quite remarkable from four perspectives. The
first is that the investigators were able to locate all fourteen of the
original subjects and obtain approval for collecting data. The approval
and data collection undoubtedly had a lot to do with the investigators'
ability to bring their video system directly to the subject instead of
having the subjects come to the laboratory. Hence, the simple one-camera
system with three surface markers provided an avenue of data collection
that would not have been possible with a multi-camera, complex marker set.
The second perspective is that significant improvements from the
preoperative measure have persisted over the twenty year period. This
includes knee and hip angular kinematics as well as cadence and step
length. An age-matched sample of subjects without disability was used to
assess improvement. It is unfortunate that data were not also collected
from a control group consisting of subjects with spastic diplegia cerebral
palsy. Ideally, such a group could have been followed in parallel to the
SDR group, but a group selected in a similar manner to the without
disability group would have also been helpful by providing another level of
comparison. The third perspective is that the investigators have set a
standard of improvement for future studies reporting on the long term
changes from SDR or any other intervention performed on children with
cerebral palsy. The results point to the need for developing gait
progression curves similar to those existing for the Gross Motor Function
Measure (GMFM).1 These curves describe the expected changes for the GMFM
over time according to different Gross Motor Function Classification System
(GMFCS) levels.2 They provide an excellent reference from which to judge
intervention efficacy. The fourth perspective is that adults with cerebral
palsy continue have gait characteristics that are different from those
without disability. There is a paucity of data describing these
characteristics as well as the effectiveness of any interventions that are
performed. Adulthood is much longer than childhood. It would seem that
the population of adults with cerebral palsy might be underserved.
It is unfortunate that the authors did not go into greater detail
regarding other existing data. For example, prior to surgery of the
original 14 subjects, four were household ambulators and 10 were
independent ambulators. At 20 years postoperatively, one subject was
unable to walk independently, one subject walked with a crutch and one with
a cane. It would have been interesting to compare their current walking
ability with their preoperative ability. It would have also been
interesting to note how any relationships that may have existed between pre-
and postoperative gait status and subsequent orthopedic surgeries.
Langerak and colleagues are to be congratulated for their outstanding
work. They have added to the body of knowledge in this area in an
unprecedented and significant way.
References
1. Palisano RJ, Hanna SE, Rosenbaum PL, Russell DJ, Walter SD,
Wood EP, Raina PS, Galuppi BE: Validation of a model of gross motor
function for children with cerebral palsy. Phys.Ther. 80:974-985, 2000
2. Russell DJ, Avery LM, Rosenbaum PL, Raina PS, Walter SD,
Palisano RJ: Improved scaling of the gross motor function measure for
children with cerebral palsy: evidence of reliability and validity.
Phys.Ther. 80:873-885, 2000
