Jump to comment:

• Ankle jerks
  William Pryse-Phillips
  Published on: 23 April 2018
• Reply to Graham Warner’s e-letter
  Chris Allen
  Published on: 20 February 2018
• Reflection on reflexes
  Graham T Warner
  Published on: 20 February 2018

• Published on: 23 April 2018

  Ankle jerks

  • William Pryse-Phillips, Professor of Medicine (Neurology) emeritus Memorial University of Newfoundland

  Sir,
  I thoroughly enjoyed reading Dr. Allen’s excellent paper on the right way to do the ankle jerk. He is quite right in saying that ‘tendon reflexes’ are not tendon reflexes. Tapping a tendon leads to stimulation of the Golgi tendon organs, which are actually inhibitory to the alpha neurones, so no response should occur. The muscle contraction probably results from the vibrations transmitted to the intrafusal muscle fibres, leading to activation of the anterior horn cells and thus causing muscle contraction in response to the stimulus. The term “deep tendon reflex” is completely inappropriate; which deep tendons can one access? Levator palpebrae superioris? Piriformis? Gluteus medius? The tendons percussed have to be superficial so that we can get at them.

  Although Dr. Allen’s method is absolutely appropriate in patients who are confined to bed, those patients who are mobile can, I suggest, be better examined if you ask them first to kneel on the seat of the chair on which they were sitting, grasping its back with their hands. They are thus unconsciously performing a Jendrassik manoeuvre, augmenting any response that their bodies might make. Their ankles, projected out behind the seat, can be tapped easily, and the response noted with equal facility.

  Now in my 80s, I cannot remember whether it was Erb or Westphal or Romberg or somebody else who first suggested this method; but after 55 years in Neurology, I still find it the best way to asse...

  Show More

  Sir,
  I thoroughly enjoyed reading Dr. Allen’s excellent paper on the right way to do the ankle jerk. He is quite right in saying that ‘tendon reflexes’ are not tendon reflexes. Tapping a tendon leads to stimulation of the Golgi tendon organs, which are actually inhibitory to the alpha neurones, so no response should occur. The muscle contraction probably results from the vibrations transmitted to the intrafusal muscle fibres, leading to activation of the anterior horn cells and thus causing muscle contraction in response to the stimulus. The term “deep tendon reflex” is completely inappropriate; which deep tendons can one access? Levator palpebrae superioris? Piriformis? Gluteus medius? The tendons percussed have to be superficial so that we can get at them.

  Although Dr. Allen’s method is absolutely appropriate in patients who are confined to bed, those patients who are mobile can, I suggest, be better examined if you ask them first to kneel on the seat of the chair on which they were sitting, grasping its back with their hands. They are thus unconsciously performing a Jendrassik manoeuvre, augmenting any response that their bodies might make. Their ankles, projected out behind the seat, can be tapped easily, and the response noted with equal facility.

  Now in my 80s, I cannot remember whether it was Erb or Westphal or Romberg or somebody else who first suggested this method; but after 55 years in Neurology, I still find it the best way to assess the ankle jerk in mobile patients.

  Show Less

  Conflict of Interest:
  None declared.

  • Back to top
• Published on: 20 February 2018

  Reply to Graham Warner’s e-letter

  • Chris Allen, Honorary Consultant Neurologist Addenbrooke’s Hospital

  It is interesting that Graham Warner mentions the sound of absent ankle reflexes. I remember discussing the thud of an absent ankle with Michael Harrison, who was my greatest clinical guru, when I was his registrar at the Middlesex Hospital in London. I have also mentioned it to my students but tended to get the l look back that tells me politely that I might not come from the same planet as them. I suspect this is because learning to examine patients involves learning novel complex perceptions. Much of this is honed over many years and like all complex perceptions involves more than one sensory modality. As neurologists, we all know that appreciating a subtle flavour involves lot more than the sensory information from the tongue; it is mostly olfactory but also involves texture and temperature as well as context and expectation. This is why to many of us the discussions of wine buffs about the subtle flavours of different vintages sound like the ramblings of someone from an alien world. Thus when teaching students one has to realise that they are learning complex perceptions in unfamiliar contexts and may not be able to appreciate subtleties such as the sound of reflexes. So their “what planet is he from?” look is appropriate because perceptually they are in a different world to that of an experienced clinician. As teachers, we need to guide them to our world of complex perceptions and not all can follow, just as I would never succeed as a wine-taster (not that I don’t like...Show More

  It is interesting that Graham Warner mentions the sound of absent ankle reflexes. I remember discussing the thud of an absent ankle with Michael Harrison, who was my greatest clinical guru, when I was his registrar at the Middlesex Hospital in London. I have also mentioned it to my students but tended to get the l look back that tells me politely that I might not come from the same planet as them. I suspect this is because learning to examine patients involves learning novel complex perceptions. Much of this is honed over many years and like all complex perceptions involves more than one sensory modality. As neurologists, we all know that appreciating a subtle flavour involves lot more than the sensory information from the tongue; it is mostly olfactory but also involves texture and temperature as well as context and expectation. This is why to many of us the discussions of wine buffs about the subtle flavours of different vintages sound like the ramblings of someone from an alien world. Thus when teaching students one has to realise that they are learning complex perceptions in unfamiliar contexts and may not be able to appreciate subtleties such as the sound of reflexes. So their “what planet is he from?” look is appropriate because perceptually they are in a different world to that of an experienced clinician. As teachers, we need to guide them to our world of complex perceptions and not all can follow, just as I would never succeed as a wine-taster (not that I don’t like a nice Malbec). Furthermore, many tendon hammers around these days have such hard rings that hitting one’s hand hard enough to listen for absent reflexes may prove a painful experience. Show Less

  Conflict of Interest:
  None declared.

  • Back to top
• Published on: 20 February 2018

  Reflection on reflexes

  • Graham T Warner, Consultant Neurologist Royal Surrey co. Hospital

  Chris Allen’s series on neurological examination offers huge relief to fellow experts who execute it incorrectly, such as the “ankle jerks”. I too use the plantar method although caution Juniors/Students to do it the right way (tendon method) when non-neurologists assess in osce’s/finals. But in teaching them how to tick the boxes I have questioned why I do what I do (self-questioning being one of the reasons I seize the opportunity to train others). I then recall as an SHO Simon Nurick (one of the people who inspired me) tellinging me to listen to the reflexes, in that when absent one hears a dull thud (rather like that of a pleural effusion, so it is interesting to learn that neurological hammers evolved from those used for respiratory examination). And it sounds more resonant when present, all akin to how taught a violin string might be, I tell them. In fact not only do I listen, as well as observe (visual observation is all that generalists teach Medical Students), but also feel. I believe this most useful when the tension in the “strings” are greatest in hypertonic such that there may be no apparent movement nor sound, but one gets tactile feed back. Hence where possible I always strike the hammer against my own hand placed carefully to achieve best transmission of the force. I suspect all “experts” draw the greater data without knowing and can so better analyse the clinical situation.
  I’m confident too that they like me may even apply varying non-standard force...

  Show More

  Chris Allen’s series on neurological examination offers huge relief to fellow experts who execute it incorrectly, such as the “ankle jerks”. I too use the plantar method although caution Juniors/Students to do it the right way (tendon method) when non-neurologists assess in osce’s/finals. But in teaching them how to tick the boxes I have questioned why I do what I do (self-questioning being one of the reasons I seize the opportunity to train others). I then recall as an SHO Simon Nurick (one of the people who inspired me) tellinging me to listen to the reflexes, in that when absent one hears a dull thud (rather like that of a pleural effusion, so it is interesting to learn that neurological hammers evolved from those used for respiratory examination). And it sounds more resonant when present, all akin to how taught a violin string might be, I tell them. In fact not only do I listen, as well as observe (visual observation is all that generalists teach Medical Students), but also feel. I believe this most useful when the tension in the “strings” are greatest in hypertonic such that there may be no apparent movement nor sound, but one gets tactile feed back. Hence where possible I always strike the hammer against my own hand placed carefully to achieve best transmission of the force. I suspect all “experts” draw the greater data without knowing and can so better analyse the clinical situation.
  I’m confident too that they like me may even apply varying non-standard forces to gain more data points and look for the degree of spread I do to judge the UMN flavour of things.
  Eponymous names are not allowed, and I don’t know if SN’s teaching was something handed down, so tendon jerk sounds cannot be labelled Nurick’s sign, but in the world of evidenced practice we can still recognise experience, wisdom and “eminence”??
  Graham Warner

  Show Less

  Conflict of Interest:
  None declared.

  • Back to top