Computer Related Upper Limb Disorder
A Keyboard to Eliminate the Stress and the Pain.
An Interim Success Report
S.W.Hobday LMIEEE. AMIEE. MIP&I.
(Originally published 4th May 1994.)
DESIGN OBJECTIVE
Research in Australia published in 1974 (1) indicated that the disproportionate amount of ill health of TELEX operators (NO DISPLAY SCREEN !!) was due to stress from the keyboard. Since mechanical constraints governing key positions no longer apply (see Appendix), the MALTRON shape was explicitly developed to remove these stresses by placing keys where fingers (and thumbs) naturally rest or can easily reach. The design is intended to be a major step towards preventing RSI or WRULD (Work Related Upper Limb Disorders) from keyboard operation.
DESIGN CONSIDERATIONS
The overall design, evolved from a careful study of minimum strain hand movement, is shown in the line diagram Fig.l. Figs. 2 & 3 show the arc of comfortable finger movement and the outward tilting of keys to reduce pronation (2). Figs. 4 & 5 show the fall in myoelectric activity needed to sustain the operating position, resulting from the reduction in the pronation and abduction operating angles (2&3).
An Interim Success Report
S.W.Hobday LMIEEE. AMIEE. MIP&I.
(Originally published 4th May 1994.)
DESIGN OBJECTIVE
Research in Australia published in 1974 (1) indicated that the disproportionate amount of ill health of TELEX operators (NO DISPLAY SCREEN !!) was due to stress from the keyboard. Since mechanical constraints governing key positions no longer apply (see Appendix), the MALTRON shape was explicitly developed to remove these stresses by placing keys where fingers (and thumbs) naturally rest or can easily reach. The design is intended to be a major step towards preventing RSI or WRULD (Work Related Upper Limb Disorders) from keyboard operation.
DESIGN CONSIDERATIONS
The overall design, evolved from a careful study of minimum strain hand movement, is shown in the line diagram Fig.l. Figs. 2 & 3 show the arc of comfortable finger movement and the outward tilting of keys to reduce pronation (2). Figs. 4 & 5 show the fall in myoelectric activity needed to sustain the operating position, resulting from the reduction in the pronation and abduction operating angles (2&3).
Sketch of Maltron keyboard 3D design
The design was improved recently by repositioning the FUNCTION keys to a full row directly above the number row, by extending the top finger rows inwards. This change removes most of the arm movement and finger stretching otherwise needed to use these keys, which are frequently required by new software such as WordPerfect 5.1. Several cases of distress caused by this additional stretching have come to our notice. In response to user comment, double SHIFT keys and a palm rest for the central number pad have now been added. Continuing this line of development a new TERMINAL keyboard features additional system operating keys in the central area, with FUNCTION keys 13 to 24 along a raised back row to give easier access.
RESULTS
Altogether about 700 (Ed: several thousand as at April 2010) DUAL HANDED MALTRON keyboards are now in use World wide and of these about 100 (Ed: this figure is c. 3000 at April 2010) currently have been effective in enabling operators with RSI to continue in work. The following case information from 20 users confirms that the design target has been achieved. Copies of letters from operators and other information is available on request.
(Name / Problem & Start date / Maltron use to date.)
Jacky Potts / Pains in wrists & arms. Oct.'93 / 7 months.
Reports back to speed, some pain but much reduced. Immediate pain on using flat keyboard. Career prospects recovered.
Paul Scarborough / Pains in hands. Oct.'92 / 7 months.
Back to speed and now no discomfort. Immediate pain if attempting to use flat keyboard. "I firmly believe it has saved my career"
Rowena Verrall / Pain in Rt. Elbow. Early '92 / 13 months.
Ease of operation made work possible even during recent reoccurrence of pain. Adapted in about 3 months and"found it of great benefit".
Mrs. M. Lee / Carpal Tunnel Syndrome diagnosed Nov.'92 / 7 months.
Back to speed and able to carry on her duties. Quickly suffers pain if she has to use a flat keyboard.
Mrs S. R. Clarke / Pain in hands & wrists. '90 / 3 weeks
Already back to speed and clear of all pain. Had had weekly massage during this last year and had various painkillers prescribed by her Doctor during this time without much success. Now says:-"I feel less tired at the end of the day and I will not have to give up my legal career" (Works from home for a Solicitor and an Accountant)
Mrs S. Peacock / Fibromalgia, hands. & wrists.'86 / 18 months.
Severe pain in hands and wrists prevented sleep. "Far less painful" after only a few weeks of using her Maltron and hands less stiff. Able to sleep better and continue her present job.
Mrs J. Batterson / Arm pain & "Fizzy fingers" '92/3 / 11 months.
Worked through the adaptation course and reported reduced pain after two weeks use.
Elaine Housby / Severe pain in hands & arms '90/91 / 28 months.
Clear of all pain in 3 months and the improvement continued. E.H. has now recovered full strength and use of hands and arms. If necessary she can use a flat keyboard for 2 - 3 hours without discomfort. After this or any use, such as carrying heavy objects, Elaine types on her Maltron for 15 minutes or so as she finds that it "has a positively therapeutic effect". Her typing speed is possibly faster than before RSI trouble (70wpm) and she can sustain this longer as "I have no aches or tiredness whatsoever in my shoulders or back". She has had no medical treatment since receiving her Maltron.
Mrs F. Higginbotham / Tenosynovitis in arms 89/90 / Started Jan'91
Reported reduced pain after 6 weeks use and hope for recovery. Initial shock of new shape "I thought I would never get used to the odd shape, but I'm glad I persevered." Contact lost through Company office closure.
Phillipa Stillwell / RSI from violin, Feb'88 / 2.5 yrs.
By July '89 P.S. had suffered loss of use of both arms and was committed to a "radical rest regime". In April '90 she started a long course of hydrotherapy, laser treatment and hand and arm stretching. This was successful in that by August '91 they were strong enough for her "to drive and lead a more or less normal life". She changed her career target from music to accountancy, but was not able to use a flat computer keyboard for more than 10-20 minutes without getting pain in her arms again. She could not write as much as a page at a time without similar pain. She started to use her Maltron in September '91 "the Maltron was a joy to use...my tiny hands did not have any large stretches", reaching a speed of about 25 wpm in 4 weeks in time to begin her accountancy course. By Feb'92 she reported that her speed was up to 50 wpm and she was able to type as long as she wanted or needed to. Also she has now bought a second Maltron for use at home.
Mrs P. Gregory / CTS diagnosed Oct'90 / 7 months.
Severe pain and off work for three months, received physiotherapy and this, with workstation improvements enabled work to continue. However in March 1993 relapsed with "excruciating pain in right shoulder and arm". Off work for 2 weeks then received a series of traction treatments, which relieved much pain but tips of RH index and middle fingers remained numb. Began use of Maltron in Sept'93 and reported a major improvement in the first day, with 95% return of feeling to finger ends. Since the second day neck and shoulder muscles have remained relaxed and pain free. Now finds typing pain free and comfortable. Would not like to return to a standard keyboard.
Ken Mardle / Tenosynovitis early'91 / 2.5 yrs.
Off work for six weeks, received physiotherapy, ultrasound and later interferencial treatments on wrists and arms. Visited Swindon Access Centre and tried a Maltron keyboard. Found he could do first two half hour sessions and then an hour with very little after effects. However on return to work in late August he found that within 3 minutes on his IBM keyboard he suffered considerable pain and had to stop. A Maltron was purchased in September and during the next 3 months pain diminished to aching at the end of a day. He has purchased a second Maltron for use with his home computer, but has to be careful about the intensity of work. He is very pleased as - "The Maltron keyboard has enabled me to continue with my job".
Rupert Teale / Back pain / 2.5 yrs.
R.T. has large hands and broad shoulders. The standard keyboard caused him to be "huddled" over the keyboard, leading to back pain due to this poor posture. The division of the Maltron keys into two well separated groups to give near zero abduction and reduced pronation has cleared this problem.
Aubrie Pecore / Spinal & CTS / 18 months.
Aubrie had not worked for 5 years due to "a multitude of spinal problems, CTS and weakness in my hands". A possible employment required keyboard use but within 10 minutes on a conventional keyboard she had to stop. With the Maltron she found that "right away I was able to type 1/2 hour to 1 hour without aggravating my symptoms" Over the next month she was able to extend this to 4 hours at a time without hurting her hands. After about 3 months she found she could type as long as she liked. Her final comments confirm design success:-"My hands haven't been this strong in years. The Maltron seems to have been actually therapeutic. Thank you for returning me to the world of the gainfully employed".
Niki Panteli / Tenosynovitis in Rt. wrist / 12 months.
Niki was a student at Warwick University. She developed tenosynovitis while a computer operator in Cyprus some 5-6 years ago. At Warwick she was treated intermittently from '92 by Sue Welford, University Physiotherapist, who comments "Physiotherapy alleviates the problem, but she has benefited more from the use of a Maltron Ergonomic keyboard". Sue was concerned that Niki's problem would return unless she could continue to use a Maltron on her return to work in Cyprus. This provision was arranged.
Jean Godbold / Tenosynovitis & CTS '90/91 / 2 years
Jean works as a transcriber for the Royal National Institute for the Blind at RNIB offices in Peterbrough. She received various anti-inflammatory drug treatments and rest, with enough improvement to continue to work "painfully". During the next 12-18 months she received Physiotherapy and Ultra-sound for her arms and later, traction for her neck. Prolonged rest and cortisone injections in her wrists followed. A CTS operation was proposed. About this time working hours were reduced to half time and she started to use a Maltron. From October '92 Chiropractic treatment was received for several weeks, "with the result that my hands/arms/neck felt 99.9% better than previously". She returned to full time working at the end of '92 and believes that recovery was due to, change in working practices, the use of the Maltron, and Chiropractic treatment. Also that "my problems would not take long to return should I ever be required to work on a non-Maltron keyboard". The Transcription Manager, Martin O'Keefe-Liddard, considers that she "has gained substantial benefit from using the keyboard" and three more operators are now using Maltrons.
Beverley Munro / RSI, Reg. Disabled '88 / 12 months.
Beverley had suffered severe disability from '88, was registered disabled and had surgical splints to immobilise her wrists. In early '93 she was given the opportunity to try a Maltron on a 4 week hire trial by the Disability Employment Service. Although she found the Maltron strange at first she immediately felt the benefits due to the position of the keys. She was able to discard her splints and has not needed to use them since "due to the brilliant design of the keyboard". At the end of the trial period, North Tyne PACT purchased it for her continuous use.
Anne Dickson / Tenosynovitis Oct.'92 / 8 months.
Was off work for 13 weeks. Found the new shape difficult to adjust to and almost gave up. However she persevered and "it suddenly came together and I now enjoy using it". Has recently had steroid injections in both wrists. Still has pain in wrists and arms and on Doctor's advice has reduced keyboard work to 3 hours per day with frequent breaks. Wishes she had known about Maltron earlier.
Sandie Maile / CTS 1985 / 4 years
Sandie works for the Society of Telecom Executives as a secretary. She received treatment for the condition, but by late '89 increasing pain made it unlikely that she would be able to continue working. She started using a Maltron in February '90 and was able to adapt to it quite quickly. In July '90 she reported almost complete freedom from pain and is now able to do a full day's work without difficulty. The only change to her workstation was the keyboard. Sandie is the first operator to demonstrate the therapeutic effects of using a Maltron in promoting recovery while working. She has now been using her keyboard for over 4 years.
Mollv Mockford / Tenosynovitis '89 / 4 years
Molly is a programmer at East Sussex County Council. She received her Maltron in early '90 following advice from her health advisers that she should try one. In October she reported "Now I hardly ever get the pain." and "As a programmer I use different keys more often than a word processor. Maltron customised my keyboard to suit me". She continues in full time use of her keyboard.
Lincolnshire County Council Highways Department. / 10 months.
The word processing pool of this Dept. had an operator suffering from keyboard related pain and ordered a Maltron on a trial basis. Due to an unexpected increase in pain the operator had been signed off sick when the keyboard arrived. A second milder case took up the opportunity to use the Maltron and discovered the benefits. The supervisor then decided to try the Maltron but the first trialist refused to give up the keyboard, so a second was ordered. The supervisor found the Maltron beneficial and decided to keep it, so a third was ordered for the original sufferer's return from sick leave. Following recovery and more trials by the other operators, a total of seven were purchased. All five operators have changed to using Maltron keyboards.
CONCLUSION
The evidence that the change of shape of a keyboard can make a substantial difference to operator health, confirms the original findings as to the source of stress and ill health. From this it follows that the standard keyboard is a prime cause of VDU stress and fatigue. That this is avoidable by a relatively inexpensive change in equipment, suggests that the first recommendation in VDU and keyboard related WRULD cases would be to ask that a Maltron keyboard should be tried.
ACKNOWLEDGEMENTS
My thanks to Dr.P.Zipp and Butterworth & Co.(Publishers) Ltd. for permission to use figures from his Paper (Figs. 4 & 5) and specially to my wife Pam, son Peter and software engineer: Jan Bennett who, with many others, have been so supportive in making this whole enterprise possible.
APPENDIX
The first practical typewriter was patented in 1868 by an American, Christopher Scholes. This early model established the standard typewriter keyboard which has remained unchanged for over 100 years. The shape of the keyboard in this early model, with the keys forming an even slope of between 20 & 40 degrees to the horizontal and with diagonal key columns, was determined by the mechanical limitations of the time.
When telex machines were introduced their keyboards followed the typewriter shape to maximise acceptance. Likewise when computers were introduced their keyboards followed the same pattern and for the same reasons. This despite the fact that electronics had separated the keys from the printing mechanism and opened the way for a complete redesign of the keyboard to overcome its known disadvantages.
REFERENCES
(1) Ferguson, D. and Duncan, J., Keyboard Design and Operating Posture, Ergonomics, November 1974, pp 731-744.
(2) Hobday, Stephen W., A Keyboard to Increase Productivity and Reduce Postural Stress. Trends in Ergonomics / Human Factors V, pp 321-330. Published by Elsevier Science Publishers B.V. Amsterdam August 1988
(3) Zipp, P., Haider, E., Halpern, N. and Rhomert, W.,
(4) Keyboard Design through physiological strain measurements. Applied Ergonomics, Vol. 14.2 June 1983, pp 117-122.
(5) Osanai, H., Ill Health of Key-punchers, Journal of Science of Labour, July 1968, pp367-371.
(6) Hobday, Stephen, W., Keyboards designed to fit hands and reduce postural stress. Proceedings of the Ninth International Ergonomics Association, September 1985, pp 457-458.
Paper presented to the: 19th Annual Congress of IMART - 4th May 1994.
The Royal Society of Medicine, 1 Wimpole St. London.
PCD Maltron Ltd. 15 Orchard Lane, East Molesey, Surrey, KT8 OBN, England.
RESULTS
Altogether about 700 (Ed: several thousand as at April 2010) DUAL HANDED MALTRON keyboards are now in use World wide and of these about 100 (Ed: this figure is c. 3000 at April 2010) currently have been effective in enabling operators with RSI to continue in work. The following case information from 20 users confirms that the design target has been achieved. Copies of letters from operators and other information is available on request.
(Name / Problem & Start date / Maltron use to date.)
Jacky Potts / Pains in wrists & arms. Oct.'93 / 7 months.
Reports back to speed, some pain but much reduced. Immediate pain on using flat keyboard. Career prospects recovered.
Paul Scarborough / Pains in hands. Oct.'92 / 7 months.
Back to speed and now no discomfort. Immediate pain if attempting to use flat keyboard. "I firmly believe it has saved my career"
Rowena Verrall / Pain in Rt. Elbow. Early '92 / 13 months.
Ease of operation made work possible even during recent reoccurrence of pain. Adapted in about 3 months and"found it of great benefit".
Mrs. M. Lee / Carpal Tunnel Syndrome diagnosed Nov.'92 / 7 months.
Back to speed and able to carry on her duties. Quickly suffers pain if she has to use a flat keyboard.
Mrs S. R. Clarke / Pain in hands & wrists. '90 / 3 weeks
Already back to speed and clear of all pain. Had had weekly massage during this last year and had various painkillers prescribed by her Doctor during this time without much success. Now says:-"I feel less tired at the end of the day and I will not have to give up my legal career" (Works from home for a Solicitor and an Accountant)
Mrs S. Peacock / Fibromalgia, hands. & wrists.'86 / 18 months.
Severe pain in hands and wrists prevented sleep. "Far less painful" after only a few weeks of using her Maltron and hands less stiff. Able to sleep better and continue her present job.
Mrs J. Batterson / Arm pain & "Fizzy fingers" '92/3 / 11 months.
Worked through the adaptation course and reported reduced pain after two weeks use.
Elaine Housby / Severe pain in hands & arms '90/91 / 28 months.
Clear of all pain in 3 months and the improvement continued. E.H. has now recovered full strength and use of hands and arms. If necessary she can use a flat keyboard for 2 - 3 hours without discomfort. After this or any use, such as carrying heavy objects, Elaine types on her Maltron for 15 minutes or so as she finds that it "has a positively therapeutic effect". Her typing speed is possibly faster than before RSI trouble (70wpm) and she can sustain this longer as "I have no aches or tiredness whatsoever in my shoulders or back". She has had no medical treatment since receiving her Maltron.
Mrs F. Higginbotham / Tenosynovitis in arms 89/90 / Started Jan'91
Reported reduced pain after 6 weeks use and hope for recovery. Initial shock of new shape "I thought I would never get used to the odd shape, but I'm glad I persevered." Contact lost through Company office closure.
Phillipa Stillwell / RSI from violin, Feb'88 / 2.5 yrs.
By July '89 P.S. had suffered loss of use of both arms and was committed to a "radical rest regime". In April '90 she started a long course of hydrotherapy, laser treatment and hand and arm stretching. This was successful in that by August '91 they were strong enough for her "to drive and lead a more or less normal life". She changed her career target from music to accountancy, but was not able to use a flat computer keyboard for more than 10-20 minutes without getting pain in her arms again. She could not write as much as a page at a time without similar pain. She started to use her Maltron in September '91 "the Maltron was a joy to use...my tiny hands did not have any large stretches", reaching a speed of about 25 wpm in 4 weeks in time to begin her accountancy course. By Feb'92 she reported that her speed was up to 50 wpm and she was able to type as long as she wanted or needed to. Also she has now bought a second Maltron for use at home.
Mrs P. Gregory / CTS diagnosed Oct'90 / 7 months.
Severe pain and off work for three months, received physiotherapy and this, with workstation improvements enabled work to continue. However in March 1993 relapsed with "excruciating pain in right shoulder and arm". Off work for 2 weeks then received a series of traction treatments, which relieved much pain but tips of RH index and middle fingers remained numb. Began use of Maltron in Sept'93 and reported a major improvement in the first day, with 95% return of feeling to finger ends. Since the second day neck and shoulder muscles have remained relaxed and pain free. Now finds typing pain free and comfortable. Would not like to return to a standard keyboard.
Ken Mardle / Tenosynovitis early'91 / 2.5 yrs.
Off work for six weeks, received physiotherapy, ultrasound and later interferencial treatments on wrists and arms. Visited Swindon Access Centre and tried a Maltron keyboard. Found he could do first two half hour sessions and then an hour with very little after effects. However on return to work in late August he found that within 3 minutes on his IBM keyboard he suffered considerable pain and had to stop. A Maltron was purchased in September and during the next 3 months pain diminished to aching at the end of a day. He has purchased a second Maltron for use with his home computer, but has to be careful about the intensity of work. He is very pleased as - "The Maltron keyboard has enabled me to continue with my job".
Rupert Teale / Back pain / 2.5 yrs.
R.T. has large hands and broad shoulders. The standard keyboard caused him to be "huddled" over the keyboard, leading to back pain due to this poor posture. The division of the Maltron keys into two well separated groups to give near zero abduction and reduced pronation has cleared this problem.
Aubrie Pecore / Spinal & CTS / 18 months.
Aubrie had not worked for 5 years due to "a multitude of spinal problems, CTS and weakness in my hands". A possible employment required keyboard use but within 10 minutes on a conventional keyboard she had to stop. With the Maltron she found that "right away I was able to type 1/2 hour to 1 hour without aggravating my symptoms" Over the next month she was able to extend this to 4 hours at a time without hurting her hands. After about 3 months she found she could type as long as she liked. Her final comments confirm design success:-"My hands haven't been this strong in years. The Maltron seems to have been actually therapeutic. Thank you for returning me to the world of the gainfully employed".
Niki Panteli / Tenosynovitis in Rt. wrist / 12 months.
Niki was a student at Warwick University. She developed tenosynovitis while a computer operator in Cyprus some 5-6 years ago. At Warwick she was treated intermittently from '92 by Sue Welford, University Physiotherapist, who comments "Physiotherapy alleviates the problem, but she has benefited more from the use of a Maltron Ergonomic keyboard". Sue was concerned that Niki's problem would return unless she could continue to use a Maltron on her return to work in Cyprus. This provision was arranged.
Jean Godbold / Tenosynovitis & CTS '90/91 / 2 years
Jean works as a transcriber for the Royal National Institute for the Blind at RNIB offices in Peterbrough. She received various anti-inflammatory drug treatments and rest, with enough improvement to continue to work "painfully". During the next 12-18 months she received Physiotherapy and Ultra-sound for her arms and later, traction for her neck. Prolonged rest and cortisone injections in her wrists followed. A CTS operation was proposed. About this time working hours were reduced to half time and she started to use a Maltron. From October '92 Chiropractic treatment was received for several weeks, "with the result that my hands/arms/neck felt 99.9% better than previously". She returned to full time working at the end of '92 and believes that recovery was due to, change in working practices, the use of the Maltron, and Chiropractic treatment. Also that "my problems would not take long to return should I ever be required to work on a non-Maltron keyboard". The Transcription Manager, Martin O'Keefe-Liddard, considers that she "has gained substantial benefit from using the keyboard" and three more operators are now using Maltrons.
Beverley Munro / RSI, Reg. Disabled '88 / 12 months.
Beverley had suffered severe disability from '88, was registered disabled and had surgical splints to immobilise her wrists. In early '93 she was given the opportunity to try a Maltron on a 4 week hire trial by the Disability Employment Service. Although she found the Maltron strange at first she immediately felt the benefits due to the position of the keys. She was able to discard her splints and has not needed to use them since "due to the brilliant design of the keyboard". At the end of the trial period, North Tyne PACT purchased it for her continuous use.
Anne Dickson / Tenosynovitis Oct.'92 / 8 months.
Was off work for 13 weeks. Found the new shape difficult to adjust to and almost gave up. However she persevered and "it suddenly came together and I now enjoy using it". Has recently had steroid injections in both wrists. Still has pain in wrists and arms and on Doctor's advice has reduced keyboard work to 3 hours per day with frequent breaks. Wishes she had known about Maltron earlier.
Sandie Maile / CTS 1985 / 4 years
Sandie works for the Society of Telecom Executives as a secretary. She received treatment for the condition, but by late '89 increasing pain made it unlikely that she would be able to continue working. She started using a Maltron in February '90 and was able to adapt to it quite quickly. In July '90 she reported almost complete freedom from pain and is now able to do a full day's work without difficulty. The only change to her workstation was the keyboard. Sandie is the first operator to demonstrate the therapeutic effects of using a Maltron in promoting recovery while working. She has now been using her keyboard for over 4 years.
Mollv Mockford / Tenosynovitis '89 / 4 years
Molly is a programmer at East Sussex County Council. She received her Maltron in early '90 following advice from her health advisers that she should try one. In October she reported "Now I hardly ever get the pain." and "As a programmer I use different keys more often than a word processor. Maltron customised my keyboard to suit me". She continues in full time use of her keyboard.
Lincolnshire County Council Highways Department. / 10 months.
The word processing pool of this Dept. had an operator suffering from keyboard related pain and ordered a Maltron on a trial basis. Due to an unexpected increase in pain the operator had been signed off sick when the keyboard arrived. A second milder case took up the opportunity to use the Maltron and discovered the benefits. The supervisor then decided to try the Maltron but the first trialist refused to give up the keyboard, so a second was ordered. The supervisor found the Maltron beneficial and decided to keep it, so a third was ordered for the original sufferer's return from sick leave. Following recovery and more trials by the other operators, a total of seven were purchased. All five operators have changed to using Maltron keyboards.
CONCLUSION
The evidence that the change of shape of a keyboard can make a substantial difference to operator health, confirms the original findings as to the source of stress and ill health. From this it follows that the standard keyboard is a prime cause of VDU stress and fatigue. That this is avoidable by a relatively inexpensive change in equipment, suggests that the first recommendation in VDU and keyboard related WRULD cases would be to ask that a Maltron keyboard should be tried.
ACKNOWLEDGEMENTS
My thanks to Dr.P.Zipp and Butterworth & Co.(Publishers) Ltd. for permission to use figures from his Paper (Figs. 4 & 5) and specially to my wife Pam, son Peter and software engineer: Jan Bennett who, with many others, have been so supportive in making this whole enterprise possible.
APPENDIX
The first practical typewriter was patented in 1868 by an American, Christopher Scholes. This early model established the standard typewriter keyboard which has remained unchanged for over 100 years. The shape of the keyboard in this early model, with the keys forming an even slope of between 20 & 40 degrees to the horizontal and with diagonal key columns, was determined by the mechanical limitations of the time.
When telex machines were introduced their keyboards followed the typewriter shape to maximise acceptance. Likewise when computers were introduced their keyboards followed the same pattern and for the same reasons. This despite the fact that electronics had separated the keys from the printing mechanism and opened the way for a complete redesign of the keyboard to overcome its known disadvantages.
REFERENCES
(1) Ferguson, D. and Duncan, J., Keyboard Design and Operating Posture, Ergonomics, November 1974, pp 731-744.
(2) Hobday, Stephen W., A Keyboard to Increase Productivity and Reduce Postural Stress. Trends in Ergonomics / Human Factors V, pp 321-330. Published by Elsevier Science Publishers B.V. Amsterdam August 1988
(3) Zipp, P., Haider, E., Halpern, N. and Rhomert, W.,
(4) Keyboard Design through physiological strain measurements. Applied Ergonomics, Vol. 14.2 June 1983, pp 117-122.
(5) Osanai, H., Ill Health of Key-punchers, Journal of Science of Labour, July 1968, pp367-371.
(6) Hobday, Stephen, W., Keyboards designed to fit hands and reduce postural stress. Proceedings of the Ninth International Ergonomics Association, September 1985, pp 457-458.
Paper presented to the: 19th Annual Congress of IMART - 4th May 1994.
The Royal Society of Medicine, 1 Wimpole St. London.
PCD Maltron Ltd. 15 Orchard Lane, East Molesey, Surrey, KT8 OBN, England.