Aammjwatch The Ball Pp25-27 May 2008

Watch the Ball … But Why? Reflexes, Injuries and Musculoskeletal Medicine Dr A Breck McKay, Bayside Medilink, Victoria Point, Queensland (mckayabATbigpond.net.au)

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usculoskeletal physicians inevitably come across many sport-related injuries and frequently hear the sporting catch phrase “watch the ball!” How many of them actually know why this is important and how it can relate to the many injuries they see? From birth onwards we learn every complex action we do by very complex amalgamations of classical Pavlovian conditioned reflexes.1 We first have to learn to roll over, to sit up, to crawl and to stand, then to walk and run, and so it goes on. Each stage can be broken down into very simple single steps which are practised again and again, until the conscious action is trained up and becomes an unconscious reflex and automatic action. Watch any baby trying to grasp something and you can easily see some of these simple steps that are practised. Watch a 6-12-month-old sitting in a chair and you will see multiple steps occurring at once, depending on which attention is being dominant. The hands and fingers are feeling the table top, the feet and legs are changing positions and the head moves depending on the visual, auditory or olfactory cues being stimulated. Now catch the baby’s attention with your eyes, open your eyes wide in response and watch the baby’s response with an overall reduction in the movement of head, body, arms and legs. The baby fixates on your eyes … a learned response from birth. This behavior change can even be effected in older children, who know they are misbehaving, and it is amazing how merely eye widening can work. It is also surprising how quickly the mother responds to the child or baby’s change in mood and activity. Young children also run into objects and people very easily, but as they get older, become very nimble with their body position in space. How many times have you seen teenagers on skateboards, zooming down pathways avoiding many people without ever touching or crashing? To understand the next concept, also learnt from very early childhood, walk directly at a person in a shopping centre but stare fixedly over their head at an object in the distance. Watch with your peripheral vision, and see how they become aware of you moving towards collision with them. They will automatically change their direction to avoid any impact without any other form of communication or acknowledgement. Just as a word of warning… do not try this with women with shopping trolleys or prams in front of them… they command right of way and will run into or through you, rather than change course. Not so with men!2 So what has this to do with “watch the ball”? Simple! The above demonstrates how we learn to position our body in space and in reference to others and objects. All is learnt by many trials and errors from childhood onwards. Now think about young children trying to kick or hit a ball. They May 2008

swing, swipe, kick and miss more times than not. Some learn very quickly and show great skill early on, others get to adulthood and just never really get it together. What is the mechanism here? The sportsperson must firstly watch the ball and from that collect the information required to swing the racquet, bat or stick. Then by the complex calculations of the brain from the visual inputs, every muscle must be coordinated and move in the correct way and at the correct time to produce contact with the ball and so make the ball do what you want! See Figure 1.

Figure 1. The eye’s mathematical processes to judge the ball’s position.

The fastest sport in the world is ice-hockey, although it is only just ahead of Olympic-grade table tennis. So what sort of ball speeds or time intervals are involved?3 Table 1. Sport

Ball Speed (kph) Distance Covered (meters) Cricket 150 20.12 Tennis 150-190+ 36.58 Table Tennis 110 1.52 Baseball 145 18.44 Ice Hockey 168 very variable (OK not a ball … Puck it!) The human body is very skilled at doing this, with some movements done automatically and some following thought and reason. The simple reaction time is 150-200 milliseconds. The time for recognition is 300-350 milliseconds. The choice plus reaction time is 400+ milliseconds. It takes sensory impulses only 20 milliseconds for the nerve impulse traveling at 50 meters per second to reach the 25

Watch the Ball … But Why?

cerebral centers and even less to activate initially the midbrain areas. The responding motor pathways take half that time to activate the muscles, conducting impulses at 100 meters per second.4 So how does the sportsperson overcome the seemingly impossible task that defies conscious recognition times? It is time to go back to anatomy, neurology and physiology and first principles to understand the processes involved. The oldest parts of the brain are the medulla, pons and mesencephalon, which house all the primitive survival/function centers and basic reflexes. To these areas are linked the olfactory, visual and auditory inputs5 which respond faster and in less than 200 milliseconds, and long before any higher cerebral center interpretation of those inputs. This Orienting or Focusing Response is not new and was described precisely by Pavlov in 1910! This is linked to the whole body function6 of vestibular postural control (Figure 2), resulting in the MOMM process. Every animal or person Monitors the environment (internal and external) then Orients (directs the vision, olfaction or auditory receptors to the change) to any change, followed by Memory check for past experience knowledge and then Manage the changed situation by flight/fight or fear/freeze or return to normal.

Figure 2. The complex whole body function process and vestibulo-posture control.

So when playing any ball sport, the aim is to watch the ball every time and to gradually develop very rapid conditioned reflexes and to increase the learned automatic reflex activation via the orienting response and the midbrain connections. Sir Donald Bradman trained his reflexes by hitting a golf ball against a corrugated iron tank. Every cricketer learns and trains his reflexes to respond automatically through the midbrain pathways. The longer one practises the better one becomes, which is just like learning to drive a car. Initially all the attention 26

is taken up listening to the instructions, watching the inside and outside rear vision mirror, looking forward through the windscreen, changing the gears, putting the clutch in and out, using the accelerator and brake pedals to move the car steadily forward, keeping an eye on the road – massive sensory input all at once – on the first occasion! Then as each set of actions becomes more familiar, it is relegated to automatic and subconscious until the brain has many superimposed automatic patterns7 which no longer need conscious thought. Some people do it easily, some less so and some never learn to drive. The same applies to ball sports as it does to any skilled process, such as being a surgeon, musician, or artisan. So a good sportsperson always watches the ball and allows their trained reflex responses to operate, often without any higher center action or interpretation. Now let us look at the opposite end of, say, a cricket pitch. The bowler is trying to exert the maximum changes after the ball hits the pitch, leaving the batsman totally unable to make any alteration for the sudden change in less than 100 milliseconds. The fast bowler uses the seam, the spin bowler the spin on the pitch and the swing bowler movement in the air over the last half of the ball’s travel. All try to make the change occur in the last 100 milliseconds, which is outside the batman’s ability to respond or alter their shot. So why is this all important to the good musculoskeletal physician? To comprehend the effects of any injury fully, one must be able to collect all past data (learnt by the patient but often forgotten), forensically dissect the detailed action occurring in any motor vehicle accident, fall down stairs, falls off horses, off bikes, onto the tailbone, etc. To do this, one must understand the normal anatomy, physiology, neurology, and so understand how, what and why an injury has occurred. Is there a simple analogy here? Of course! The atlas of human anatomy is just like the road map of many suburbs. Ask any patient to tell you the names of the last six side streets they pass on the way home. If they recently moved in, they can. If they have been there for years they have trouble. Why? It’s because they forget the details which they pass every day. If they need to go to Melbourne or Sydney or Brisbane by car, they need a road map (or GPS) to find where they are and how to get to their destination! Doctors learn their anatomy in the first few years at medical school, just like a road map and then as they become familiar, they forget the details, but good musculoskeletal physicians use the atlas every day and with every patient, thus reinforcing their knowledge and noticing/learning new bits all the time. They learn to tease out the mechanism of injury in any past event that the patient remembers distinctly, and consider its effect on the whole body,6 as well as specific parts of the body. On the other hand specialists learn their anatomy and physiology not once but twice and in massive detail to pass their primary examinations. But as they progress they become used to using a single motorway without any Australasian Musculoskeletal Medicine

Watch the Ball … But Why?

side streets in one part of the body, all too often forgetting the other bits. All doctors must return to their anatomy, etc., to ensure that they remember the details properly.

Why is this like “watch the ball”? Simply because, to any good doctor, if you do not watch the ball/anatomy, do not seek all the relevant past history, you will never be able to react automatically when you are faced with a new injury or difficult musculoskeletal problem. To become good musculoskeletal physicians, we must practise again and again and not get into bad habits of thinking and recording things which we may not have done. We all know from patients’ information that some specialists may fail in history taking and may do very cursory examinations, (or which may not have been done at all), yet the printed records suggest otherwise. So when addressing any injury in any patient: 1. Take a thorough pain history and examination 8

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2. Go back to the basic injury process involved (it may be for any injuries that are remembered). 3. Review for forensic deconstruction (step by step) of the mechanisms of injury. Determine the biomechanical processes and factors involved.

References 1. Pavlov IP. Lectures on Conditioned Reflexes. The Classics of Psychiatry and Behavioural Sciences. Library Reprint Gryphon Editions, 1991 from the original text 1928. Chapters VIII p. 103, XI p. 131, XXVII p. 276 and XXVIII p. 282. 2. Kandel ER, Schwartz JH, Jessell TM. Perception of Motion Depth and Form. Principles of Neural Science. 4th ed. McGraw Hill, 2000. Chapter 238 pp. 548-71. 3. Kosinski RJ. A Literature Review on Reaction Time.

Clemson University. 4. “The Pathophysiology of Pain”. AstraZeneca Pharmaceutical Education Booklets. J Pain and Symptom Management 2000; 19 (15). 5. McKay AB. Tennis Elbow Everywhere. Australas Musculoskeletal Med 2005; 10(2): 127-30. 6. McKay AB, Wall D. The Orienting Response and the Functional Whole Human Body. Australas Musculoskeletal Med 2003; 8(2): 86-99. 7. de Bono E. The Past Organises the Present: The Jelly Model, Short Term and Long Term Memory. The Mechanism of Mind. Simon and Schuster, 1969. Pp. 93-97, 111-16. 8. Bogduk N, McGuirk B. History. Medical Management of Acute and Chronic Low back pain. An evidence based approach. Elsevier, 2002. Chapter 6 pp. 28-40. 9. Bogduk N, McGuirk B. Physical Examination. Medical Management of Acute and Chronic Low back pain. An evidence based approach. Elsevier, 2002 Chapter 7 pp. 41-47.

4. Consider and explain the simple anatomical factors involved using an atlas of anatomy, not sketches which only confuse and leave the patient uninformed. 5. Explain how nociception passes via the spinal cord to the brain. 4 6. Re-examine the patient by actually physically touching and pressing on the involved areas.9 7. Explain what, why and how you are going to treat the patient. 8. Remember everything you do has been learnt, just as any sportsperson learns, by classical Pavlovian conditioned reflexes and the commitment of knowledge from conscious to subconscious and thus reflex and automatic for most of it. (Most of what you do is automatic and if learnt incorrectly, it is easily in error!) 9. “Watch the ball” to be a good musculoskeletal physician, and now you know why!

May 2008

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