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Tendon Hammer

Introduction
Public summary: 

Have a go at using a tendon hammer to show and explain some strange reflexes...

Using a tendon hammer to show and explain some strange reflexes
Useful information
Kit List: 

Tendon hammer

Packing Away: 

Hammers live in a flat grey box.

Frequency of use: 
2
Explanation
Explanation: 

ACTIVITIES
-try to demonstrate some common reflexes

THINGS TO TALK ABOUT:
- what is a reflex? (see below)
-why do we have reflexes (here you could talk about reflexes in general i.e. blinking) - reflexes are there to protect us
-Why would we want to test reflex action? By testing reflexes, doctors can find out if there is nerve damage etc.

TIPS FOR DEMONSTRATING:
It is often difficult to show the reflexes on the kid. A good idea is to try it out on yourself first. If all else fails, you could try to demonstrate some other reflexes; i.e. demonstrate blinking; demonstrate the pupil reflex (get one kid to close their eyes for a bit and then open them; does the pupil size change?) - you can have one kid doing it whilst the others watch and then swap, so everyone gets to see them

BASIC PROCEDURE AND EXPLANATION:

- Getting the reflexes to work can often be tricky. Try to find them on yourself/one of the other demonstrators first. (Hitting a bit harder often also helps.)
- If in doubt, ask a committee medic to show you how to elicit different reflexes.

These are some of the reflexes you could try:

- Do they know where any of the reflexes are?
- Get them to relax and try to elicit the reflexes:

A Arm:
1. Biceps: put your thumb on distal bicep tendon and tap that.
2. Supinator: Put your finger their forearm (distal radius over the supinator muscle) and tap it.
3. Triceps: bend their arm and tap distal tricep tendon.
4. finger: Lay their fingers over your index finger and tap your index finger.

B Leg:
1. Knee: get them to cross their legs and tap the patella tendon.
2. Ankle: Sit them on high ledge (if you have one), dorsiflex the foot and tap the achilles tendon.
3. Babinski's: if they've got shoes that are easy to take off, run your finger up the lateral side of their sole.

Most of these won't work in kids, because they don't relax. You could try reinforcement.
i. Upper limbs: get them to grit their teeth.
ii. Lower limbs: Get them to clasp their fingers together and pull.
iii. NOTE: reinforcement only works for a very short period of time so you must do it at the same time as you bang the reflex.
d. If you can't get a reflex there's no point bashing away at the same limb, because your chance of getting decreases each time -; try the other limb.

EXPLAIN WHAT A REFLEX IS:

a. Start with nerves: wires that carry messages from body to brain (SENSORY) and brain to body (MOTOR). If the kids are small, you can say it's a bit like a telephone line - messages travel from one phone to another.

b. There are some things we need to do so quickly that we haven't got time to send messages to and from our brain.
- Can they think of any?
- Use the example of blinking when something goes near eye.
- We also have reflexes in our arms. What do we need those for?
- Ask them if they've ever touched anything that's very hot.
- We also need reflexes in our legs, why?
- Ever stepped on something sharp.
- So we have reflexes to protect us
- Balance?
- Posture - what keeps us upright? Lots of muscles! If we sway forwards some of our muscles pull us back without us having to think about it
- (Also note in both cases the reflexes stop the tendons being stretched too far)

OTHER THINGS TO TALK ABOUT:

This usually works better if the kids are a bit older:

- why does a doctor want to test your reflexes
-get them to think about nerve damage and how you could assess that
-usually asking is a good idea (i.e. can someone feel something, see if they can move their arm etc.)
-however, what do you do if someone can't talk and doesn't move (i.e. in an accident when someone is unconscious)
-can then test if reflexes still work (i.e. doctors have pocket lamps; they can test the pupil reflex in an unconscious patient)

Risk Assessment
Date risk assesment last checked: 
Sat, 11/02/2017
Risk assesment checked by: 
Fiona Coventry
Date risk assesment double checked: 
Mon, 13/02/2017
Risk assesment double-checked by: 
Tdwebster
Risk Assessment: 
DESCRIPTION Using a tendon hammer to show reflexes
RISKS
  • One end of the hammer tapers to a point - risk of getting into eyes
  • Risk of bruising if used with excessive force
  • ACTION TO BE TAKEN TO MINIMISE RISKS
  • Do not let children use tendom hammer without supervision, don't let them get boisterous and over-excited with the tendon hammer
  • Use medics who have been taught how to use the hammer, or someone who has been shown by a committee medic how to use the hammer.
  • Do not use tendon hammer with excessive force
  • ACTION TO BE TAKEN IN THE EVENT OF AN ACCIDENT
  • Call first aider in case of injury
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