Year : 2016 | Volume
: 2 | Issue : 2 | Page : 69--70
Interventions on hyperexcited motor circuits: Science or bias and confusion – what can be done?
Aniruddh Kumar Purohit
Aniruddh Kumar Purohit
|How to cite this article:|
Purohit AK. Interventions on hyperexcited motor circuits: Science or bias and confusion – what can be done?.Indian J Cereb Palsy 2016;2:69-70
|How to cite this URL:|
Purohit AK. Interventions on hyperexcited motor circuits: Science or bias and confusion – what can be done?. Indian J Cereb Palsy [serial online] 2016 [cited 2019 Apr 19 ];2:69-70
Available from: http://www.ijcpjournal.org/text.asp?2016/2/2/69/204412
It is interesting to note that the interventions on hyperexcited spasticity or dystonia-related motor circuits (mono- or poly-synaptic) have two extremes. On one extreme, there are nonablative procedures (chemo-denervations, say, botulinum toxin or intrathecal baclofen injection; deep brain stimulation)thathave recurrence or to say are reversible. These are mostly very expensive with recurrent expenditures and require regular review with physicians. Whereas, on the other extreme, there are ablative procedures (rhizotomy, fasciculotomy, soft-tissue release, etc.) having no recurrence and helplessness to reverse (that are permanent). However, these are comparatively less expensive, have no recurrent expenditures, and do not require lifelong regular review with physicians.
All these interventions, indeed, modulate pathological impulse transmission through otherwise anatomically normal circuit (anterior horn nuclei, motor spinal roots, motor fascicles, muscles, and sensory spinal roots with supra-segmental control). Therefore, it is extremely important and challenging to learn what interventions are indicated and when on these otherwise normal structures, till one discovers those methods that may repair the real pathological entity of the damaged brain or spinal cord.
Historically, in the year 1861, the orthopedic surgeon William John Little (1810–1894) was the first to publish surgical procedure, the tendo achilles release, for the relief of focal problem of cerebral palsy (CP), the equinus deformity of the foot. However, in the year 1887, Lorez first published the report on obturator neurectomy for relief of another focal problem of CP, the hip adduction. This was Sherrington's experiment in the year 1898 on a decerebrate cat with reduction in spasticity which did open the field for relief of diffuse spasticity. In fact, Foerster was the first scientist to perform posterior rhizotomy on human beings in the year 1908 for the relief of diffuse spasticity.
During and following this period, many orthopedic surgical procedures also came into practice for focal and diffuse spasticity involving various muscles. In fact, various other neurosurgical procedures also evolved during this period such as peripheral neurotomies. This was Sindu (1985) who developed selective neurotomies on various peripheral nerves following Fasono's development of neurostimulation in the year 1977 for selective posterior rhizotomy and Peacock's modification in the year 1981.
Historically, like this, various procedures have evolved over the past 150 years and are being practiced according to the experience of medical specialists. In fact, the procedures have remained in vogue mostly during the first few years of the discovery. However, during subsequent years, the real indications could be established in comparison with other preexisting procedures, based on expensiveness (say highly expensive BT and ITB) and the socioeconomical wisdom while managing these children, keeping in mind the importance of entire family, have also emerged. This has made to flourish the practice of one particular method (say BT and ITB) in developed countries and almost no practice in underdeveloped countries. Whereas, the developing countries, as usual, under confusion (medical vs. socioeconomical constraints) practiced both the expensive and less expensive methods randomly.
There is also confusion due to bias with one or two methods practiced regularly by neuro- or ortho-surgeons versus physicians' bias who can easily perform chemo-denervation (inject BT, phenol, etc.).
Concern due to the possibility of recurrence of hyperexcitability with various methods (BT surely, ortho, much possible, and neuro, least possible) also prevails among the affected family and treating team.
How much neural tissue a neurosurgeon should cut and how much muscle an orthopedician should lengthen (”undercorrection” is in more consideration but the word itself means not fully corrected) is another dilemma among clinicians; to use electrophysiological methods for the selection of hyperexcitable rootlets or fascicles was in vogue (since Fasano introduced electrical stimulation for rhizotomy) but it has declined presently (except for some research studies to see changes in the nervous system).
The often-changing scenario about various interventions creates doubts whether the present procedure is really good. And who knows the long-term results. Not only this even single event multi-level orthopedic surgeries (”to avoid doing surgery on every birthday,” in fact is an emotional sentence like “surgery without knife” and this term also excludes neurosurgical procedures in an orthobias) or to have multistage orthoneuro surgeries (a few neurosurgeries and/or orthosurgeries at a time) is indeed a challenge to the medical fraternity that is not yet answered by the specialists worldwide.
The confusion is also in relation to loosing squat to stand by Eggar's operation (transplantation of knee flexors into extensor compartment) which has to do a lot with lifestyle of an individual with cerebral palsy in different countries. One can afford to loose this function to some extent in developed countries (use of Western commode, to perform work on table in sitting position). However, one cannot afford to loose in the underdeveloped and developing countries (Indian-style commode, working in sitting position on the floor, walking on the uneven roads). Where do surgical indications stand for geographical differences?
All these examples are good enough for a physician to define the surgical indications and types of surgeries based on socioeconomical, geographical, lifestyle practices, and the type of vocation.
What about physical methods to reduce hyperexcitability of muscles and to develop control and balance. This first-line management that should continue following whatsoever interventions are done, if true, is poorly emphasized by most physicians and vice versa. The severe spasticity that is unyielding with physical methods, child is having pains, his orthotic devices are breaking, and is developing contractures, but many a times, the child's caretakers are not made aware to seek suggestions from a surgeon at an appropriate level of progress.
In fact, there are no evidence-based, prospective, multimodality comparative studies to answer the above-mentioned many and many more queries/confusions. In fact, the confusion gets multiplied in the mind of families much more when the managing team itself is confused. To resolve all these, some of the national and international medical groups and associations have to develop alliances for multimodality, prospective, evidence-based scientific studies with funding from noncommercial organizations of the respective countries (such as DST, CSR, etc., in India) and international bodies.