Presentation is loading. Please wait.

Presentation is loading. Please wait.

Ergonomic Issues in the Courtroom Judicial Studies Board for Northern Ireland 29 th May 2007 Dr Ken Addley Director NICS OHS www.nicsohs.gov.uk.

Similar presentations


Presentation on theme: "Ergonomic Issues in the Courtroom Judicial Studies Board for Northern Ireland 29 th May 2007 Dr Ken Addley Director NICS OHS www.nicsohs.gov.uk."— Presentation transcript:

1 Ergonomic Issues in the Courtroom Judicial Studies Board for Northern Ireland 29 th May 2007 Dr Ken Addley Director NICS OHS

2 Outline The back, posture, seats and sitting The back, posture, seats and sitting Computers and writing Computers and writing

3 Evolution – the Computer Age

4 The Vertebral Column

5 General Characteristics Formed from 26 irregular bones Formed from 26 irregular bones Axial support of trunk Axial support of trunk Surrounds and protects spinal cord Surrounds and protects spinal cord Provides attachment points for ribs and muscles of back Provides attachment points for ribs and muscles of back

6 The Spine Cervical is the neck area made up of 7 vertebrae and curved inward or lordosis Cervical is the neck area made up of 7 vertebrae and curved inward or lordosis Thoracic is mid-back with 12 vertebrae and has outward curve or kyphosis Thoracic is mid-back with 12 vertebrae and has outward curve or kyphosis Lumbar area is lower back with 5 vertebrae and is curved inward or lordosis Lumbar area is lower back with 5 vertebrae and is curved inward or lordosis Sacrum is below lumbar and is solid mass of bone. Sacrum is below lumbar and is solid mass of bone.

7 Anatomy: Soft Tissues Nerves branch off the spinal cord. Nerves branch off the spinal cord. Ligaments are small, non-elastic bands that connect to the discs and vertebrae, lending support and stability to the spine. Ligaments are small, non-elastic bands that connect to the discs and vertebrae, lending support and stability to the spine. Muscles have strong attachments to the vertebrae along the entire length of the spine - strongest in their mid-range position Muscles have strong attachments to the vertebrae along the entire length of the spine - strongest in their mid-range position

8 Anatomy: Bones & Discs  Bony vertebrae;  Facet Joints – 20% weight  Discs – 80% weight

9 L5 L4 L3 L2 L1 T12 T11 Spinal Cord Intervertebral Disc Vertebral Body

10 Back Pain

11 Low Back Pain affects 7 out of 10 people affects 7 out of 10 people commonest at age yrs commonest at age yrs 10 Million working days lost 10 Million working days lost £481 million cost to NHS £481 million cost to NHS £5 billion cost to industry £5 billion cost to industry

12 Risk Factors for Back Pain Increase force/stress Increase force/stress Repetitive Motion/twisting/Forward bending Repetitive Motion/twisting/Forward bending Poor or improper lifting techniques Poor or improper lifting techniques Poor posture Poor posture Poor Job design Poor Job design Deconditioned/Poor physical fitness Deconditioned/Poor physical fitness Overweight Overweight Tall stature Tall stature

13 Common Back Problems Strains and sprains Strains and sprains Facet joint pain Facet joint pain Disc erosion Disc erosion Sciatic nerve impingement Sciatic nerve impingement Herniated discs Herniated discs

14 Strains and Sprains Commonest cause of Low Back Pain Commonest cause of Low Back Pain A pull on the soft muscle fibres causing bruising inside the muscle. A pull on the soft muscle fibres causing bruising inside the muscle. Excessive pressure on the joints and those ligaments attached to the joints. Excessive pressure on the joints and those ligaments attached to the joints. Symptoms - stiffness, pain & aching, loss of mobility. Symptoms - stiffness, pain & aching, loss of mobility.

15 Disc Problems (1) Acute - excessive and unusual stress and strain forces on the back. Acute - excessive and unusual stress and strain forces on the back. Chronic - ageing, wear and tear and past injury (Degenerative Disc Disease): - 35% Healthy Male Volunteers have significant DDD Paajenan et al - 90% people age >50 have DDD Miller et al Chronic - ageing, wear and tear and past injury (Degenerative Disc Disease): - 35% Healthy Male Volunteers have significant DDD Paajenan et al - 90% people age >50 have DDD Miller et al

16 Disc Problems (2) Herniated / Bulging Disc

17 Posture

18 Lumbar Disc Pressures

19 Mechanics: Poor Posture Spending long periods of time in abnormal positions is stressful and damaging to the spine. Spending long periods of time in abnormal positions is stressful and damaging to the spine. With increased lumbar lordosis, facet joints are under increased pressure, nerve root spaces become smaller, and muscle and ligaments are shortened. With increased lumbar lordosis, facet joints are under increased pressure, nerve root spaces become smaller, and muscle and ligaments are shortened. Means that the spine’s normal curves are exaggerated or decreased creating stresses and strains in the tissues. Means that the spine’s normal curves are exaggerated or decreased creating stresses and strains in the tissues.

20 Ideal Posture The ideal posture is governed by: The chair The chair The task The task The person The person Sitting habits Sitting habits

21 The Chair

22 Low Back Support

23 Chair Height Adjust or use foot rest

24 Chair Height Feet flat on floor Feet flat on floor May need a foot rest May need a foot rest Thighs parallel to the ground Thighs parallel to the ground Or knees slightly lower than hips Or knees slightly lower than hips

25 Seat Pan Depth Too Long: can cut off circulation Too Short: does not provide enough support Incorrect Incorrect

26 Seat Pan Depth 1-2 inches from back of knees to front of seat Correct

27 Ankles Tucked

28 Leaning forward

29 One size doesn’t fit everyone!

30 Adjust the chair to suit

31 A Good Ergonomic Chair Well-designed and adjustable Provides support to the back, legs, buttocks and arms, while reducing exposure to awkward postures, contact stress and forceful exertions.

32 The Task

33 Not unduly repetitive Not unduly repetitive No fixed, awkward or rigid postures No fixed, awkward or rigid postures Tolerable working environment Tolerable working environment Equipment ergonomically designed Equipment ergonomically designed Pace of work manageable Pace of work manageable Adequate training Adequate training Task matched to the individual Task matched to the individual

34 The Person

35 Trained and competent Trained and competent Not anxious or tensed Not anxious or tensed Complies with safe system of work Complies with safe system of work Adjustment for disability Adjustment for disability Seek help, advice or guidance Seek help, advice or guidance

36 Sitting

37 Pick the Better Posture

38 Sitting geometry In unsupported chair (no back) - the spine tends to flatten. In unsupported chair (no back) - the spine tends to flatten. With a lumbar support - the spine tends to retain its natural shape. With a lumbar support - the spine tends to retain its natural shape. Sitting in a chair place your forearm in the curve of your lower back and sit back in your seat this gives you an idea of a good sitting posture Sitting in a chair place your forearm in the curve of your lower back and sit back in your seat this gives you an idea of a good sitting posture

39 Sitting & low back pain Some research shows a relationship between low-back pain and prolonged sitting. Others do not. Some research shows a relationship between low-back pain and prolonged sitting. Others do not. Drivers who sit longer than 3.5 hours/day have a 3x increase in risk of disc herniation. Drivers who sit longer than 3.5 hours/day have a 3x increase in risk of disc herniation. HSE recommends 15 min break per hour for computer operators. HSE recommends 15 min break per hour for computer operators.

40 Bad Posture: Sitting Slumping in chairs. Slumping in chairs. Sitting with legs folded to one side. Sitting with legs folded to one side. Sitting with ankles crossed. Sitting with ankles crossed. Slipping down the seat. Slipping down the seat. Persistently leaning forward. Persistently leaning forward. Sitting on edge of seat Sitting on edge of seat

41 Prolonged sitting – do stretches throughout the day to keep your muscles flexible and avoid injury.

42 Computers & Writing

43 The Digital Courtroom

44 Available Resources 1. Document Camera 2. Touch Screen Annotator 3. Laptop Computer Video Hookup Audio/Video playback 5.Touch Screen Annotator

45 Ergonomically Correct Work Station Head Level Head Level Shoulders Relaxed Elbows at Sides Wrists straight Low Back Supported Feet Supported Line of Sight

46 Work Surface Height

47 Normal Working Area

48 Musculoskeletal Problems

49 Musculoskeletal Disorders Common self-reported work- related illness Major reason for seeking healthcare Major reason for work absence - 10 million days/yr - ave time off 18 days Mostly no objective pathology

50 Upper Limb Disorders (1) A variety of soft tissue injuries affecting the muscles, tendons and nerves of the hands, arms, shoulders and neck A variety of soft tissue injuries affecting the muscles, tendons and nerves of the hands, arms, shoulders and neck If connected to work, also known as: If connected to work, also known as: Work related Upper Limb Disorder (WRULD) Work related Upper Limb Disorder (WRULD) Repetitive Strain Injury (RSI) Repetitive Strain Injury (RSI) Cumulative Trauma Disorder (CTD) Cumulative Trauma Disorder (CTD) Occupational Overuse Syndrome (OOS) Occupational Overuse Syndrome (OOS)

51 Carpel tunnel syndrome Carpel tunnel syndrome Cubital tunnel syndrome Cubital tunnel syndrome Thoracic outlet syndrome Thoracic outlet syndrome Raynaud’s syndrome (white finger) Raynaud’s syndrome (white finger) Rotator cuff syndrome Rotator cuff syndrome DeQuervain’s disease DeQuervain’s disease Tendinitis Tendinitis Tenosynovitis Tenosynovitis Trigger finger Trigger finger Ganglion cyst Ganglion cyst Upper Limb Disorders (2)

52 Historically thought to be caused by repetitive movements of hands or arms, usually at speed and for prolonged periods ("dynamic loading") Historically thought to be caused by repetitive movements of hands or arms, usually at speed and for prolonged periods ("dynamic loading") Later, awkward/fixed postures ("static loading") Later, awkward/fixed postures ("static loading") Importance of "non-physical" factors recently recognised by HSE. Importance of "non-physical" factors recently recognised by HSE. Use of keyboards and mouse devices Use of keyboards and mouse devices Upper Limb Disorders (3)

53 Use of Keyboard and Mouse (1) Keep your fingers relaxed. Keep your fingers relaxed. Use a soft touch on the keyboard instead of pounding keys with unnecessary force. Use a soft touch on the keyboard instead of pounding keys with unnecessary force. Grasp the mouse gently – move using elbows not wrists. Grasp the mouse gently – move using elbows not wrists. Avoid holding a pen or anything else in your hands while you type or use the mouse. Avoid holding a pen or anything else in your hands while you type or use the mouse.

54 Use of Keyboard and Mouse (2) Relax your fingers and hands between bursts of typing or mousing using a flat, neutral straight wrist posture. Relax your fingers and hands between bursts of typing or mousing using a flat, neutral straight wrist posture. Don't rest your elbows on hard surfaces. Don't rest your elbows on hard surfaces. Use an Optical pick-up mouse. Use an Optical pick-up mouse. Rest your eyes occasionally by focusing on distant objects. Rest your eyes occasionally by focusing on distant objects.

55 Writer’s Cramp

56 Diseases of Scribes and Notaries “Incessant driving of the pen over paper causes intense fatigue of the hand and the whole arm because of the continuous and almost tonic strain on the muscles and tendons, which in course of time results in failure in the right hand.” “Those who suffer most from these ailments are book-keepers and accountants, as they are called, for example those who hire themselves to work for merchants. Also we must reckon in the same category the private secretaries of princes.” “In winter they must take care not to let the hands grow numb from excessive cold, so they must be protected by good thick gloves.” 1713: Ramazzini: De Morbis Artificum Diatriba

57 Writer’s Cramp- Sir Richard Gower 1893 “The occurrence of the disease is influenced less by the amount than by the manner of writing. There are in writing two chief elements: the way in which the pen is held, and the way in which the movements are effected.”

58 He finds that he is grasping the pen too tightly, and cannot help doing so; taking a firmer hold seems to increase the difficulty, and he finds that he writes slowly, as if a weight were attached to the hand. The hand feels strangely tired, and an aching pain in the finger or thumb or first metacarpal bone, or in the wrist or forearm, makes it still more difficult for him to go on writing. Writer’s Cramp- Sir Richard Gower 1893

59 Gowers recognised that lawyer’s clerks are especially affected by reason of their cramped position. He described four methods of writing: (1)The hand resting on the little finger; movement of the pen by the fingers and the thumb. (2)The hand resting on the wrist; lateral movement assisted by the abductors of the wrist. (3)The middle of the forearm used as a fulcrum. (4)The arm moved freely from the shoulder; the fingers scarcely move. He found that cramp occurred especially in the first two groups; writers using the last method are immune. Writer’s Cramp- Sir Richard Gower 1893

60 The best and only free method is to write from the upper arm and shoulder, with no fixation of the arm; the forearm, wrist and little finger rest on the table so as to take some of the weight of the limb from the shoulder-muscles, but both wrist and forearm move along the table as the writing progresses from left to right. In this way the pen can be held lightly; very little of the movement is effected by the small muscles of the hand; the fingers scarcely alter their position, except when a stroke is carried far above or below the line; and even for this a movement of the fingers is not always necessary. Writer’s Cramp- Sir Richard Gower 1893

61 Summary – Computers & Writing Ensure desk surface at correct height – adjust chair if necessary Ensure desk surface at correct height – adjust chair if necessary Use mouse correctly – optical pick-up Use mouse correctly – optical pick-up Don’t grip pen too tightly Don’t grip pen too tightly Don’t use a thin pen Don’t use a thin pen Don’t hold a fixed posture – avoid hovering Don’t hold a fixed posture – avoid hovering Take time to stretch when away from the desk Take time to stretch when away from the desk

62 Summary - Sitting Choose your seat carefully and adjust to suit Choose your seat carefully and adjust to suit Don’t slump Don’t slump Don’t cross your legs or ankles Don’t cross your legs or ankles Don’t adopt fixed postures Don’t adopt fixed postures Take time to stretch when away from the desk Take time to stretch when away from the desk

63 Northern Ireland Civil Service Occupational Health Service NICS Centre for Workplace Health Improvement Lincoln Building Great Victoria Street Belfast BT2 7SH Website:


Download ppt "Ergonomic Issues in the Courtroom Judicial Studies Board for Northern Ireland 29 th May 2007 Dr Ken Addley Director NICS OHS www.nicsohs.gov.uk."

Similar presentations


Ads by Google