Study Protocol for CTS and Keyboard Controlled Randomized Trial
Study Protocol for CTS and Keyboard Controlled Randomized Trial
The study hypothesis is that there is a relationship between the keyboard layout and carpal
 tunnel syndrome (CTS). Specifically, use of the standard QWERTY keyboard increases the risk
 of symptoms of carpal tunnel syndrome. The QWERTY keyboard requires more effort by the
 fingers than necessary to perform the required work, i.e. data or word entry; up to 200
 percent more flexion and extension and 100 percent more distance traveled.

 The purpose of the protocol is to evaluate two keyboard layouts for carpal tunnel syndrome
 therapy, and to see if the efficient keyboard, Finger Relief, can be used as an adjunctive
 tool to other treatments or therapy for CTS for typists. Subjects who had received a
 diagnosis of carpal tunnel syndrome from their medical doctor and, where not contraindicated,
 had received confirmation of the diagnosis of carpal tunnel syndrome with a nerve conduction
 velocity (NCV) study participated in four typing sessions to compare onset and severity of
 carpal tunnel symptoms. Testing sessions alternated between keyboards. The keyboard selected
 for the first typing session was determined by random assignment. Twenty subjects completed
 all four typing sessions. The test protocol consisted of a medical history, 3 tests of the
 subjective pain experience of the subject (visual analogue scale / verbal rating scale, and
 hand diagram), 2 clinical measures of physical manifestations of swelling associated with
 carpal tunnel syndrome (water volume/tape measure), and a measure of the length of time spent
 typing on each keyboard layout - QWERTY and TheOrdinals (the Finger Relief keyboard).
The current study is the first clinical study of a keyboard with patients diagnosed with
 carpal tunnel syndrome. Previous research has compared the angular motion of the fingers in a
 comparison of QWERTY, Dvorak and Finger Relief keyboards (Robertson et al., 1995). However,
 in these studies the subjects had no diagnosis of carpal tunnel syndrome.

 The typing test used typical English word combinations of letters which could be easily
 repeated for any layout. On the QWERTY keyboard, pressing the D and E flexes the middle
 finger. TheOrdinals letters (A D E H I L N O R S T) on QWERTY has 6 flexions, 1 each for the
 left middle; right middle, right ring, right index, 2 each left index fingers. TheOrdinals on
 Finger Relief keyboard have no flexions or extensions of the fingers The keystrokes were
 noted. The goal was to type to pain, change in feeling, numbness or tingling. The beginning
 and ending time was recorded manually with reference to a wristwatch or clock. Each of the
 four typing sessions ranged from 20 minutes (very little typing occurred) to more than an
 hour (extensive typing occurred without a report of symptoms). Pretyping measurement
 activities took about 10 minutes, including completing the analogue scaled self reporting
 test and water displacement test. Following this pretyping data collection, the subject was
 instructed to type until a change in pain was noticed. Post-typing measurement activities,
 including water displacement, a check for swelling, and self-report measures also took about
 10 minutes.

 The subject was then scheduled to return to the clinic no sooner than until an overnight had
 passed, or after any swelling has gone down. The protocol was repeated on a similar keyboard
 with only the letters rearranged. On the Finger Relief keyboard, pressing the D and E
 requires minimal flexion, as pressing the middle and index finger on the home row
 communicates the letters.

 The study population was those who had been diagnosed with carpal tunnel syndrome. The FDA
 asked that the reference group consist of 20 individuals (no restrictions for the number of
 men and women). There were no minimum or maximum requirements of age, subjects were only
 required to have a history of carpal tunnel syndrome or similar problems when performing
 typing activities prior to study enrollment. Each subject confirmed a history of carpal
 tunnel syndrome, presumably causing difficulties in performing typing activities. However
 typing problems were not required for participation.

 A total of 64 subjects responded to the study advertisements. Thirty-three of these subjects
 did not enter the study. Many were missing either the NCVS or a diagnosis of carpal tunnel
 syndrome from a doctor (14). Several did not respond to attempts to schedule study sessions
 (8). A few moved away from the area prior to study participation (4) or were too ill to
 participate (2). The remainder had insufficient interest to commit to participate in four
 testing sessions (3); were looking for treatment options, rather than a CTS study (1); or
 were advised by an attorney to decline participation in a CTS study, pending litigation that
 the subject was pursuing (1).

 Thirty-one subjects completed the all steps before beginning the typing exercises, which
 included a medical history, informed consent, CTS diagnosis, and NCVS confirming the CTS
 diagnosis. Eleven withdrew or left the testing incomplete. Ten of the eleven dropouts were
 employed at office work, the other was employed as a registered nurse. Five withdrew prior to
 initiating study sessions. Six withdrew after beginning a study session but before completing
 the remaining sessions and did not respond to efforts to schedule the remaining tests. Four
 dropouts started with the QWERTY layout. Two started with Finger Relief. Four dropouts
 completed only one study session (three started with QWERTY, one began with Finger Relief).
 Two dropouts completed two study sessions (one began with QWERTY, one started with Finger
 Relief). Twenty subjects completed all 4 study sessions and are included in the analyses
 described in later sections of this application.

 Swelling is a hallmark of CTS, because the median nerve must be compressed. Prior to this
 study, it was unknown whether swelling could be externally measurable in the least severe
 cases. Although the literature suggests that there is some swelling in all stages (1, 2 or 3)
 of CTS cases, the literature did not designate swelling by stage. Classic inflammation is
 measured by fever (rise in temperature), color (redness), swelling and pain. Only swelling
 and pain are externally measurable, without invasive procedures. The pre typing hand and
 wrist volume were the base line from which swelling was measured. Assuming typing causes
 measurable swelling, before the subsequent typing sessions, a sufficient time had to have
 passed for the swelling to return to base line. Thus, base line was defined as a return of
 external parameters (pain and swelling) to that which was measured before the first typing
 test session.

 Swelling was measured by comparing the increase in hand volume before and after the activity
 as measured by the water displacement method. Water displacement was measured to determine if
 an increased amount of water from the hand and wrist measurement was displaced after typing
 on QWERTY keyboard as compared with typing on the TheOrdinals (the Finger Relief keyboard)
 keyboard. It was hypothesized that there would be a significant relationship between the
 increased amount of water and the use of the QWERTY keyboard.

 The data were analyzed using a personal computer and statistical software. Calculations
 between the differences of means of swelling and pain, between the QWERTY and TheOrdinals
 (the Finger Relief keyboard) keyboards were completed. Regression techniques were used to
 estimate the differential impact of typing with each keyboard on swelling and pain. Means
 differences and regression techniques were also used to examine the effect of keyboard type
 on duration of typing.
Inclusion Criteria:

 -  Diagnosis of carpal tunnel syndrome

 -  Completion of a nerve conduction velocity study (NCVS) within the past twelve months
 or a physician waiver of the NCVS

 -  Able to type using all fingers on the keyboard

 Exclusion Criteria:

 -  Do not use all of their fingers when typing

 -  No active symptoms of carpal tunnel syndrome

 -  Unable to type, or flex and extend the fingers, for whatever reason

 -  Unable or unwilling to provide informed consent

 -  Use of pain relievers or medications during study sessions (potentially masking
 symptoms of median nerve entrapment)

 -  Unable to complete the typing activities before their symptoms (swelling associated
 with body ailments or metabolism) changed

 -  Had inconsistent subjective and objective evaluations in the preactivity test

 -  Threaten or abuse the investigator

 -  Unable to perform the activity so as to meet the minimal use requirements

 -  Had such injury as they had no sensation in their hands (i.e. Late stage)

 -  May suffer further injury (as indicated by their medical history) by attempting the
 typing activity

 -  Had non CTS related metabolic problems and upper extremity neurologic conditions,
 current or past, which have similar symptoms to median nerve entrapment, but which
 were not due to median nerve entrapment in the carpal canal