Evolutionary factors in rehabilitation

S — SECOND QUARTER, 1970 Acta Neurol. Scand., 46, 2, 1970: F o g , R., and P a k k e n b e r g , H.: Combined Nitoman Pimozide Treatment of Huntington’s chorea and other hyperkinetic syndromes. Summary: On the hypothesis that, in contrast to Parkinson’s disease, hyperkinetic syndromes are characterized by an increased sensitivity of dopaminergic receptor cells to a normal level o f dopamine (or by increased dopamine turn­ over), the authors treated 16 patients with drugs which are known to have a strong anti-dopamine effect. The majority of the patients suffered from Huntington’s chorea. En­ couraging results were obtained, with striking reduction of hyperkinesia in 9 patients and moderate reduction in 5. Acta Neurol. Scand.: Supplement No. 43, 26, 2, 1970: This supplement, which is the Proceedings of the Nine­ teenth Congress of Scandinavian Neurologists, includes several interesting short papers on the pharmacology of Parkinson’s disease and its treatment by L-dopa and other

The australopithecine fossils discovered in South and East Africa, and described by Professor Raymond A. Dart in his "Adventures with the Missing Link" , have made it possible for me to write this article on the associations between evolution and rapid results in rehabilitation. Until the recent interpretations o f this fossil evidence were published, my ideas have been conjectural, but now that evidence is available in a form that is easy to utilize it seems appropriate that 1 should submit this article for publication in South Africa. A further reason for doing so, is that South African Physiotherapists are aware of the importance of Man's past history. Yet, we must go warily in using evolu tionary evidence, because of the conflicting view s of scientists who have studied our genealogy. I sent the draft o f this article to Professor Dart, and he replied that it is very appro priate to have the attention of physiotherapists drawn to the bearing upon their remedial exercises of the phylogenetic information about human ancestry that has been accumulated during the past century. I am grateful for his amendments to my draft.
This article claims that there are great advantages if the patient utilizes trends which are implicit in his bodily and mental make-up, instead of trying to learn afresh by voluntary effort. We have become so used to learning by voluntary exercises that it is difficult to recognize that this presents any problems. Surprisingly, this is double time-consuming; firstly, using voluntary effort to learn movements which are normally automatic takes a long time, and secondly voluntary controlled movement may include awkwardness and rigidity which have to be unlearned. It is found that the conditions and behaviour from which sequences of muscular reflexes arose have been pushed back further into the past than was previously thought. Fortunately, as Sir Wilfred Le Gros Clark's book "Man-Apes or Ape-Men" (1967)* shows, sufficient fossil evidence has been interpreted to give us some clues worth following up as regards our remote ancestors' relevant muscular behaviour which was the basis o f these reflexes.
Much useful work on reflex activities in connection with brain damaged individuals has been done in England, also in America (based on the ideas o f Temple Fay). It seems to me that this approach should be more fully exploited with a wider range of patients. Personally, I was lucky, having been introduced to the subject many years ago; in 1929 Sir Arthur Keith explained to me his belief that rehabilita tion treatment should follow the lines of evolution. In my experience the results from following this advice are assured and are often rapid.

Guiding Factors
Before describing some examples of this use o f ancestral reflexes, it is necessary to mention two guiding factors which were discussed by Le Gros Clark in a lecture on "Sensory Experiences and Brain Structure" (J.ment. Sci., Vol. 104, No. 434, Jan. 1958).

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In most countries Prosthetic Research units, and units solely for the care of the amputee, are few and far between. In a great many countries they do not exist at all. Limbs and appliances are still required and it invariably falls to the lot of the physiotherapist to do something about it. The role of the physiotherapist in the successful rehabilita tion of the amputee is vital, to keep the patient fit, to attend to the stump, and to educate in the use of the prosthesis. A sound knowledge of prosthetics is essential and can do much to keep those "skeletons" out of the cupboards.
Factor A. For our present purpose, we must study reflex actions in groups and sequences. This contrasts with their study in Physiology in which they tend to be analysed into separate units, each of which comprises a sensory and a motor component. We can term this grouping of reflexes factor A, based on the following argument.
In his lecture, Le Gros Clark quoted experiments by G. E. Coghill, when discussing total responses to external stimuli in which the body and limbs act as a whole. These total responses occurred during a stage of development of the central nervous system, when the latter was composed of a diffuse network of nerve cells and fibres. This supports his point, that this "primitive foundation still persists in large measure in the adult brain -even in the human brain" . He emphasized the above which is "in contra-distinction to the rather widely held view that it is the local reflex that is the primary unit of behaviour and that these reflexes become only secondarily linked up by some integrative mechanism at a higher functional level of the nervous system" .
It is clear that in rehabilitation we cannot take advantage of reflexes which the human race has lost genetically, also that the physical existence of a primitive foundation of nerve cells is no evidence that we can make a practical use of them. Yet, if we can discover sequences of reflexes which we can trigger into action almost without training we can use them as preludes to the refined movements which we desire patients to acquire. If so, there will be an enormous saving of time and effort. It is therefore worth investigating the working conditions which encourage this link between far off past and the immediate present. Factor B relates to the sensory aspect of these reflex move ments. Le Gros Clark's lecture discusses the significance of our brain's aptitude to sift, sort, and integrate the items of its sensory inflow, chiefly, as the title o f the lecture suggests, in connection with sensory experiences, but this processing of the sensory inflow to the brain also determines motor responses. I have found that the addition of appropriate supplementary sensations to the sensory inflow sets going a sort of re-integration, which often creates an immediate improvement in co-ordination and a decrease of pain. These supplementary sensations often arise in the eyes and ears. They also originate from movements indirectly, because they arise in another part of the body which is affected by the movement. The following example of this occurs, when a patient has pain and difficult movement as regards straightleg-lifting after an operation on his knee. He may in fact find that his quadriceps muscles refuse to act. If then he places the tip o f an index finger against the proximal border of the patella with the pad of the finger on the tendon, and tries to discover whether he can feel minimal movements of the tendon, he is likely to be favourably surprised when his patella butts against the tip o f his index finger. This move ment, which is triggered by sensations from his hand, en courages its repetition on a "little and often" basis.

Some practical examples
The examples given below illustrate what appear to have been common-place behaviours of our remote ancestors, as suggested by fossil evidence and other considerations.

Visual and auditory sensations
The muscular responses which are triggered by these distance receptors are often better co-ordinated and "smoother" than comparable actions prompted by voluntary efforts. A large proportion of the sequences and groups of reflexes which underlie the commonplace movements of everyday life are initiated by, and modulated by, sensations which stem from the eyes; especially by sensations arising from the visual reflex mentioned in the next paragraph. This fact, however, often fails to be realized, because these muscular responses throughout the body, including those of the hands and feet, occur at speed without the causative sensations having been consciously appreciated. The com plexities of eye/hand co-ordination and eye/leg co-ordination, which are legacies from ancestral achievements, should be fully exploited during rehabilitation.
A visual reflex which suits our present discussion occurs, whilst driving a car, when another vehicle arrives unexpected l y at a road junction, so that the image o f the latter impinges on the very edge of the car-driver's retina. This stimulus does not reach his consciousness, but triggers muscle action which brings the moving object: -the other vehicle -into his central vision. An item in this response is the turning of the head towards the vehicle; and in the case of some individuals there is a violent defensive contraction o f the homolateral abdominal wall; at this stage, of course, the driver is fully aware of the other vehicle and his own surprise.
The visual aspects of this sequence o f reflexes are discussed by Professor R. L. Gregory, in his book "Eye and Brain" (1966). He also describes the antiquity of this reflex and the structure of the periphery, or very edge of the retina which is primitive, pointing out that this reflex would have enabled our remote ancestors, as a matter o f urgency, to distinguish friend from foe.
In connection with rehabilitation, movements initiated as above, or visually under other conditions, are likely to be far smoother than those under voluntary control. By using supplementary sensations from the patient's hands, the reflex movements of the head can be limited in extent and direction appropriate to his condition. Only a patient with painful neck movements who has experienced this difference, which occurs naturally and without training, is in a position to recognize the difference. There is no merit in a patient's trying to recover normal neck movements by voluntary control "through pain". This reflex is seen in the human infant. It is of interest to appreciate that a patient, recovering from a stroke with poor balance, may fall unexpectedly, if subjected to this reflex.

SOME REFLEX ACTIONS IN THE FEET
Out of the many reflex actions which occur in the feet, when balancing the body, whilst standing, walking or running, a pair of reflexes in the forepart o f the foot will now be examined. These reflexes press the pad of the big-toe against the ground and draw the lateral portion o f the foot towards the hallucial portion. It is easy to do this, and is worth doing it carefully, because these reflexes are important components in several complicated and fleeting sequences of reflexes.
A chance observation, which I made in 1929, shows that this pair of reflexes can develop at an age when there is no conscious or learned control of the foot muscles. I watched a child of 16 months lift quite heavy objects, whilst balancing firmly in the standing position. The diagram (Fig. 1) shows the areas of wear and the creases which had already been made in the soft leather sole of her slipper; these relate purely to balancing, because, when the child moved across the room, she always insisted on shuffling along on her behind. The wear under the pad of her hallux was marked, showing that intrinsic muscles were active in making the hallux into a lever, whilst balancing. The longitudinal crease (AB in Fig. 1) between the two distinct areas o f wear under the transverse plantar pad showed that other intrinsic reflexes were involved.

Keith's Hypothesis
In 1929 I took my sketch of the infant's shoe to Sir Arthur Keith. He was most interested and gave me a reprint o f a lecture which he had recently given on "The History of the Human Foot and Its Bearing on Orthopaedic Practice" (J.B. &J.Surg., Jan. 1929). He had discussed his hypothesis regarding the first step in the transformation of our ancestors' arboreal foot into a terrestrial foot. In the former role the foot acted as a firm support on which the body balanced by reason of its grip on the bough. When on the ground, however, in contradistinction to the ancestors o f the apes, our ancestors adopted the pair of reflexes described above, thereby helping to make the foot into a flexible and resilient support and lever. Keith also showed the diagram of a new-born baby's foot (see Fig. 2) on which I have drawn two dark lines to emphasize the angle between the axes of the tarsus and the forepart o f the foot. Fossil evidence suggests that this is a legacy from the past.
Interpretation of Fossil Evidence. In his book, "Man-Apes or Ape-Men", Sir Wilfred Le Gros Clark discusses the australopithecine fossils discovered in South and East Africa by Dart, Broom and Leakey. When reporting on a talus bone found in South Africa, he writes that the "inward extension o f the articular surface of the head, perhaps, allowed for a greater deflection inward of the body weight to the forefoot in association with a mobile big-toe capable of some degree o f divergence from the other toes" . I wrote to Sir Wilfred about Keith's hypothesis of an ancestral medially-directed big-toe pressed to the ground with the lateral portion of the forefoot adducted towards the big-toe, and he agreed with Keith's hypothesis. When describing the East African fossils, Le Gros Clark showed that the talus had the characteristics described above, also that " . . . there is a joint facet between the bases of the metatarsal bone of the big-toe and that o f the second toe making it clear that there was no divergence between these toes as in the anthro poid apes" . Thus, the fossil feet appear to have conformed to Keith's hypothesis and to the diagram of the new-born human babe. They emphasize this pair of reflexes, retained by Man. Recovery of This Pair of Reflexes. It may sound a simple matter to tell a patient to press the pad o f his big-toe against the ground; but this is exactly what he is unable to do. The reason for this inability is two-fold: structural changes in his foot due to faulty muscular habits and changes in his control processes (he can no longer exercise his normal voluntary control). In order to recover this pair of reflexes, the patient must take advantage o f Factors A and B, mentioned above, and must choose working conditions which supply appropriate sensory impulses. DECEMBER, 1970 When balancing the body on the foot, this pair of reflexes help to make the foot into a resilient lever, but this also requires activity in the Anterior Tibial muscle and the strap like Abductor Hallucis, which strengthens the medial border of the foot. It is easy for the patient to notice with his fingers the activity of both these muscles. Thus, it is wise to choose working conditions which encourage activity in these two muscles, expecting that their activity will be associated with the desired pair of reflexes in the forefoot.
In addition to attending to this positive side of the recovery, there is activity which must be avoided; patients who have lost this pair of reflexes as a rule have faulty muscular habits in their feet. Instead o f raising the forefoot by means o f the Anterior Tibial muscle, they do so largely or entirely with the extensor muscles of the toes, and this misuse of muscles persists when balancing the leg on the foot. This bad habit must be adjusted before the appropriate ratio of activity between the long and the intrinsic muscles of the feet can be restored. Without this adjustment o f muscular habits the pair of reflexes cannot be recovered, because of the above-mentioned structural changes.
Working Conditions. These are chosen so as to provide an appropriate sensory inflow to the patient's brain.

It will be a great help to the patient if he can reach his ankle with his hands when he is sitting with his heel and the pad (not the tip) of his big-toe each supported on, say,, a piece of wood or a book. This leaves a depression between the two supports to accommodate the thickened plantar pad below his metatarso-phalangeal joints. Then he can use his hands to straighten out these joints and the interphalangeal joint of his big-toe. Should he find that tight skin on the dorsum of his foot or under all his toes prevents
his efforts to straighten out his foot, he will require to soften the tight skin by applying an ointment and cautiously stretching the skin. By doing this himself, he will hasten recovery of the missing reflexes by improving their sensory aspect. The hands and additional movements of the foot supply supplementary sensations which aid voluntary control of the foot.
As soon as the patient has begun to overcome the mechanical obstruction of the shortened skin, he can place his foot, so that it forms a bridge between the abovementioned heel and toe supports, and his fingers can hold the pad (not the tip) of his big-toe in position on the latter. With his heel well supported, he can place a finger on the front of his ankle over thetendonof hisAnteriorTibialmuscle and another finger on the strap-like Abductor Hallucis. He can now reduce the support o f his foot by his fingers, using them to feel whether these two muscles come into action, when he tries to maintain the shape of the bridge formed by his foot. The physiotherapist can feel whether the intrinsic muscles are beginning to co-operate, as synergists; this is a prelude to the recovery of the group of reflexes which involves all these muscles.
Under these working conditions when the finger support for the foot is reduced, it is clear that various muscles become subject to 'stretch', and this is the stimulus that triggers the group of reflexes. These conditions supply the requirements of Factors A and B, without which progress would be slow. On the other hand, with these factors fully operative, patients with long-standing, faulty, muscular habits in their feet may make rapid progress.

The Next
Step. Supplementary sensations from the fingers should be utilized from time to time with the foot operated as a bridge, until flexibility in the foot has been restored and the longitudinal crease (AB in the diagram) has begun to return. The fingers should raise the foot into the arched position with the arch high; then they should allow the arch to lower slightly (stretching the intrinsic muscles) and immediately the foot muscles should restore the height of the bridge. Under these conditions, reflex action soon takes over from voluntary control. The patient should avoid making any pronounced voluntary effort, because this will encourage the tip of the hallux to move laterally and to flex at the interphalangeal joint -relapses into previous bad habits.

A Sequence of Reflexes. Keith's hypothesis (op. cit.) on the history o f the human foot includes the influences o f the long muscles which balance the leg on the foot, stabilize the ankle,
strengthen the instep and help to support the arch. In 1930 I investigated the pair o f reflexes in the forepart of the foot, which we have been discussing, by observing the areas of contact when one foot is supported on a sheet o f plateglass; these conditions include the above influences o f the long muscles and make the study of this pair o f reflexes of the short muscles easy. After discussing the matter with Keith, I published a couple of diagrams which showed what occurred when the body-weight was transferred from being equally supported on both feet to full support by the foot on the plate-glass. Under full load, provided the big-toe was acting as a lever in aid of body-balance, the foot actually narrowed and the longitudinal crease (AB in Fig. 1) was emphasized.
In this example the lever-action of the big-toe was triggered and automatically modulated by instability of the body on the single foot. If, however, this reflex action of the big-toe fails and there is a consequent failure to supply the necessary sensory impulses from the big-toe, stretch o f the intrinsic muscles alone is inadequate to trigger the stretch-reflex action, and the foot remains wide under full load. Thus, in rehabilitation o f the foot supplementary sensations are needed as a prelude to the stretch impulses. In brief, the lever-action o f the big-toe against the ground helps to provide anchorage for the attachments o f the long muscles which help to balance the leg on the foot, stabilized in part by the pulls of their tendons. In addition, this action of the big-toe provides a sensory prelude to the stretch reflex of the intrinsic muscles. This pair of reflexes in the forepart of the foot has become a normal sequence of reflexes.

An unexpected event forced me to make a renewed study of the reflexes of the hand, coupled with the use o f supple mentary sensations which help to increase versatility of movement and voluntary control over the fingers. Professor Raymond A. Dart sent a Professor of Music in an American
University to discuss with me the basis of handskills for his music-making pupils, and overcoming postural defects which interfere with breath-control. I have found that a particular, near-reflex action in the hand forms the basis from which sophisticated handskills can be rapidly differentiated. Formerly, when I practised Physiotherapy, I found this action invaluable as a basis from which a variety of useful actions in rehabilitation can be developed. This raises a problem as to why this particular reflex is so potent, and this problem will be discussed.
Reflexes in the Hands. The reflex, mentioned above, rarely occurs in the behaviour of modern man, but it can be incor porated automatically as an item in an easily produced, generalized activity of the arms. This reflex consists o f the thumbs being stationary, whilst the rest of the hand is being accelerated towards the thumb, the hand being somewhat opposed to the thumb. This contrasts with the commonplace action of moving the thumb and fingers towards each other when gripping an object -the "precision grip" (Napier). The muscle action in the two movements is somewhat similar, but the sensory inflows to the brain which trigger either action are in contrast.
If one experiences how this reflex can be simulated in one's own hand, it helps one to imagine the ancestral activities from which they are legacies.
In this article we are looking for ancestral activities which were significant, e.g., which were important for survival, and were adequately used but without undue specialization. This is because experts hold that our remote ancestors were

I versatile creatures with various modes o f locomotion fhmiich the forests involving their hands. Versatility has h pn an important feature in our evolution, yet this has not r p v e n t e d t h e development o f muscular reflexes.
f e / H a n d Co-ordination and the Brain. Before considering t h e simple procedure which enables this "hand-towardsthumb reflex" to be simulated in one's own hand, interaction f the brain, eyes, and hand must be mentioned. Both in e v o l u t i o n and in rehabilitation there is an interaction between (a) the educative effect of eye/hand co-ordination on the brain and (b) the effects of processing the sensory inflow to the brain on the reflexes and structures o f the hand. Thus when considering either rehabilitation or evolution of hands, we must keep in mind both mental processes and actions in other parts of the body, including contributions from the eyes. to his wrist, and should carry his right hand forwards, so that the pad of his right thumb makes contact with the point at which he is looking, allowing his right fingers to over-shoot his left forearm. This will cause a 'Stretch' o f the intrinsic muscles which will encourage the rest o f his right hand to be adducted towards the thumb, and the fingers to flex around the forearm. The hand is somewhat opposed to the thumb, the amount of this depending on the direction of thrust by the right arm. The combination of reflexes is | modulated by the influence o f the eyes which includes impulses due to the graspable appearance of the left forearm. It may help to improve eye/hand co-ordination, if the example on peripheral vision, described above, is incorpo rated as a prelude to looking at the prospective point of contact on the left forearm.
Rehabilitation. If the disability in the right hand is con siderable, movements of the arm will have to be restrained; even so, it is better to start with a generalized activity in the hand instead of aiming at the use of only a few muscles. This elementary eye/hand co-ordination under visual in fluence is of definite value.
I have found that it is the sequence of the sensory input to the brain, not its intensity, which is effective. Accordingly, it can be of value to patients who have damaged and painful hands capable only of restrained movements.
After one or two experiments with this example, the patient ran rest Jhis right hand and forearm on a table or on his thigh, and, holding his right thumb still with his left fingers, he can slide his right fingers towards his right thumb, using various combinations of muscle action, as instructed; these should include arching up the dorsum o f the right hand, so that there is some opposition relative to the right thumb. If desired his left hand can stretch his right intrinsic muscles, before they are activated.

DECEMBER, 1970
ANCESTRAL BEHAVIOUR The aim of these final remarks is to show how these reflexes may have arisen as a result o f our ancestors' common place behaviour, and thus demonstrate why this handtowards-thumb reflex is potent.
In his "Antecedents of Man", Sir Wilfred Le Gros Clark (1962) postulated that the ancestors of Man had developed swinging by the arms' as a means of travelling through the forests only to a moderate degree. Dr. John Napier in an article in New Scientist (12th July, 1962) suggested that "the remote ancestors o f man had developed as specialized arboreal forms capable of leaping through the forests with a certain amount o f swinging by the arms, ..." Fossil Evidence. This is discussed in "Man-Apes or Ape-Men" by Le Gros Clark, throwing light on the hands of these creatures, and suggesting the activities o f their ancestors. He reviews the fossil evidence brought to light in South and East Africa by Dart, Broom and Leakey. He suggests that the ancestors o f man began their terrestrial life at a time when drier climatic conditions were thinning out the forests, forcing our ancestors to scamper from one group of trees to the next. This would have supplied the need to jump onto and over slender boughs near the ground, enhancing eye/hand co-ordination.
The fossil evidence includes a robust, well-developed and curved 1st metacarpal bone and a 4th metacarpal with strong interosseous markings (Napier), showing that these interosseous muscles were well developed. At another site there was evidence of an opposable thumb capable of finer manipulative activities. The characteristics which can be deduced from this fossil evidence compare with those found in human hands, but are in contrast with the specialized features of the apes which are used for swinging from branch to branch through the forests. Landing on Slender Boughs. The next step in this discussion fits in with the "hand-towards-thumb" reflex, triggered by 'stretch' o f the intrinsic muscles. This 'stretch' will be shown to have arisen from landing safely on a slender bough after a leap or fall, as part o f commonplace behaviour, when playing, fighting or reaching out after fruits. Success in landing must have encouraged further leaps, if we accept Le Gros Clark's contention that our ancestors were agile creatures. In the above-mentioned simulation the left fore arm represents the slender bough of our remote ancestors. Landing successfully on a slender bough must have involved two visual influences which attained survival value. The first related to the selection o f a suitable slender handhold which could be grasped, and the second to aiming the thumb appropriately at the near side of the bough. D . Denny-Brown's book*-shows that, when falling or landing in the "head-down" attitude, mammals have their fore-limbs out-stretched reflexly, and that monkeys retain this reflex action with their hands open and thumbs widely divergent. The sensory input from the neck helps to trigger this response, when the head is held so that the line of sight is directed onto the landing area. When the animals began to land on slender boughs, clearly the visual placing of the hands must have been far more exact, so as to avoid accidents and to control the travel of the body. This must have enhanced eye/hand co-ordination, and strengthened the structure and versatility o f the hand.
During this behaviour, the reflexes of the intrinsic hand muscles contrasted with the reflexes of animals which swung from bough to bough. As soon as the thumb came into contact with the near-side o f the slender bough, the intrinsic muscles which joined the rest of the hand to the "fixed" thumb must have received a 'stretch' and would have con tracted smartly. This, then, is one of the features which made our ancestors different from the ancestors o f the apes. It has produced reflexes which are the basis of our handskills. I wrote to Sir Wilfred Le Gros Clark about these sugges tions concerning the hand, and he replied that they were *"The Cerebral Control o f Movement" (Liverpool, 1966).