Treatment effectiveness for patients with a history of repetitive hand use and focal hand dystonia

Treatment Effectiveness for Patients with a History of Repetitive Hand Use and Focal Hand Dystonia: A Planned, Prospective Follow-up Study Nancy N. ByI, PhD, PT, FAPTA Professorand InterimChair Department of Physical Therapy and Rehabilitation Science UCSFjSFSU Graduate Program in Physical Therapy University of California-San Francisco; Peter OstwaldHealth Program for PerformingArtists San Francisco, California

Alison McKenzie, PhD, PT Assistant Professor Department of PhysicalTherapy Chapman University San Francisco; Assistant Clinical Professor Department of PhysicalTherapy and Rehabilitation Science UCSFjSFSU Graduate Program in PhysicalTherapy University of California- San Francisco

The incidence of symptoms related to repetitive motion of the hand continues to grow despite increased attention to ergonomic modifications at the workplace.lf Excessive musical practice, increased use of computers, unrealistic demands for productivity in the workplace, and stressful competition for success contribute to the problem.V Injuries related to repetitive motion are usually thought to result from soft tissue microtrauma (e.g., Corresp ondence and reprint requests to Nancy N. Byl, PhD, PT, Professor and Interim Chair, Graduate Program in Physical Therapy, Department of Physical Therap y and Rehabilitation Science, University of California-San Francisco, 1320 Seventh Avenue, Box 0736, San Francisco, CA 94143; e-mail:.

ABSTRACT: Recent studies show that rapid, nearly simultaneous, stereotypical repetiti ve fine motor movements can degrade the sensory representation of the hand and lead to a loss of normal motor control with a target task, referred to as occupational hand cramps or focal hand dystonia. The purpose of this prospective follow-up study was to determine whether symp tomatic patients in jobs demanding high levels of repetition could be relieved of awkward, involuntary hand movements following sensory discriminative retraining complemented by a home program of sensory exercises, plus tradi tional posture, relaxation, mobilizati on, and fitness exercises. Twelve patients participated in the study . They all had occupational hand cramps, as diagnosed by a neurologist. Each patient was evaluated by a trained, independent research assistant before treatment and three to six months after treatment, by use of a battery of sensory, motor, physical, and functional performan ce tests. Care was provided by a physical therapist or a supervised physical therap ist student in an outpatient clinic. Patients were asked to stop performing the target task and to come once a week for supervised treatment that included 1) heavy schedules of sensory training with and without biofeedback to restore the sensory representation of the hand , and 2) instructions in stress-free hand use, mirror imagery, mental rehearsal, and mental practice techniqu es designed to stop the abnormal movements and facilitate norm al hand control. Patients were instructed in therapeutic exercises to be performed in the home to impro ve postural alignm ent, reduce neural tension, facilitate relaxation, and promote cardiopulmonary fitness. Following the defined treatment period, all patien ts were independent in activities of daily living, and all but one pa tient returned to work. Significant gains were documented in motor control, motor accuracy, sensory d iscrimination, and physical performance (range of motion, strength, posture, and balance). This descriptive study that includes patients with occupation-related focal hand dystonia provides eviden ce that aggressive sensory discriminative training complemented by traditional fitness exercises to facilitate musculoskeletal health can improve sensory processing and motor control of the hand. JHAND THER. 2000;13:289-301.

tissue anoxia, inflammation, swelling, and scarring) and poor body mechanics associated with compromised positions of head, trunk, and upper extremity alignment.' Poor alignment with gravity can create muscle imbalance, performance inefficiency, and nerve compression.' With a focus on the peripheral tissue, conservative treatment includes rest (e.g., splinting the affected joint and taking time off work) and anti-inflammatory medications .' This treatment is usually effective when the patient is not working . However, when the patient returns to work and places the hands in the performance position on the target instrument, the symptoms usually return ... as if the hand remembers something about the target October-December 2000 289

task. Continued performance of the repetitive, stereotypical, fine motor movements, coupled with stress, high motivation, and compulsive perfection, can lead to the development of motor control problems of the hand, referred to as repetitive stress injury-focal hand dystonia (RSI-FHD) or occupational hand cramps.b---20 Repetitive stress injury-focal hand dystonia is one of the disabling task-specific limb dystonias.i" It is characterized by painless, arrhythmic, involuntary co-contractions of the flexor and extensor muscles of the hand during the performance of a specific target task like typing, writing, or playing a musical instrument. 4,6,8,10,12-20 Lack of reflex inhibition is associated with uncontrollable co-contractions of the flexors and extensors, along with inaccuracy, poor timing, and abnormal sequencing of individual finger and wrist movements during task performance.i' Gross motor control and unrelated fine motor movements are typically reported as normal during the clinical neurologic examination. However, in the history or on physical examination, risk factors can be identified, such as a previous fall on an outstretched arm or nerve compression at the carpal tunnel, thoracic outlet, or neural foramina,22,23 or anatomic restrictions limiting finger abduction, forearm rotation (supination or pronation), or shoulder rotation. 24-26 Still other researchers have documented the following causes of focal hand dystonia: dopamine depletion/" sensory motor integrative problems (e.g., with grasping),28 loss of reflex inhibition.i" failure to isolate stimuli occurring nearly simultaneously/" diminished response to somesthetic temporal stimuli/" sensory de-differentiation as measured by chan§es in the map of the primary sensory cortex (area 3b)9, 0-32 and inaccurate sensory discrimination.32-36 Repetitive stress injury-focal hand dystonia is persistent, and it does not disappear when the target task is stopped. In simple hand dystonia, the problem remains target-specific, but in dystonic-type hand cramps, the movement dysfunction can spread to other similar tasks. If the symptoms present in the foot or leg or in childhood, the problem may be ftrogressive and may lead to generalized dystonia. 0 If the symptoms present in the upper extremity during adulthood, they usually do not progress.l" Some researchers suggest that the neural consequences of rapid, repetitive, near-simultaneous movements lead to central somatosensory degradation, which disrupts the normal sensorimotor feedback loop and ultimately can lead to loss of normal fine motor control. The emergence of these profound somatosensory changes paralleling focal dystonia in monkeys and in human patients has been documented. 9,29--31,34-36 Neuroscience research provides strong evidence that the orderly, somatosensory topographic representations of the cutaneous signals of the body can be modified as a result of attended, repetitive activities, 290 JOURNAL OF HAND THERAPY 2000

tactile stimulation, functional tasks, or injuries (e.g., amputation, syndactyly, or stroke). Some of these changes represent positive adaptations37-54; others represent negative adaptations. 29-31,35,36,55-57 Rapid alternating contraction of finger flexors and extensors is associated with nearly simultaneous sensory inputs to both the cutaneous receptors of the hand and the proprioceptive, muscle, and joint afferents. Monkeys performing at high levels of repetition (16 trials/minute) developed motor dysfunction similar in appearance to that seen in patients with focal hand dystonia (tremor on opening and closing, difficulty opening after closing, and involuntary writhinp-type movements when opening and closing).30,3 The somatosensory representation of the trained hand was seriously degraded, whether the monkey's hand was opened and closed passively (in 20 msec) or actively. The receptive fields were very large and many neuronal penetrations had multiple receptive fields. Also, the receptive fields frequently extended across multiple fingers or across the glabrous and dorsal surface, a finding rarely seen in normal primates." Interestingly, anatomic dissection of the hands of these monkeys did not reveal any signs of acute inflammation of the tendons, the tendon sheaths, or the median or ulnar nerves. However, one monkey did have a congenital defect of the flexor digitorum sublimus and flexor digitorum profundus tendons. Although the tendon defect was also present in the untrained hand, the monkey developed movement problems only on the trained side.25 " Recently, similar changes in somatosensory organization of human patients with focal hand dystonia were reported by Bara-Iiminez et a1. 35 Candia et a1. 55 reported positive improvement in hand control in patients with focal dystonia following a well-controlled, constrained-use paradigm designed to force individuals to do specific, repetitive, isolated motor retraining of the involved digits. These researchers did not address any underlying somatosensory dysfunction, yet still reported improvement in motor control. The question is whether specific sensory discriminative retraining aimed at restoring the normal sensory representation of the hand will facilitate the restoration of normal motor control. Two case studies have reported on the effectiveness of sensory discriminative training in the improvement of hand control. In one study/" a patient developed hand dystonia after working 16 to 17 hours a day at the computer. Significant clinical changes were reported in performance following a sensory discriminative retraining program complemented by ergonomic modifications in the workstation, modified hand use, therapeutic posture, neural tension, and fitness exercises. In the second case study,57,58 a musician was started on a sensory discrimination retraining program

complemented by the same therapeutic exercises as the previous patient, but mental rehearsal and mental practice activities were also incorporated into her program. She mentally practiced playing her instrument "normally." Both patients were initially evaluated with a clinical battery of sensory and motor tests to objectively describe their sensory and motor performance. The second patient was also evaluated with magnetoencephalography to map the evoked potentials from the somatosensory cortex following taps to the digits. Both patients were seen once a week for supervised treatment, and each was to carry out an intense home program. The first patient was treated over six months. The second patient participated in three six-week periods of treatment. Both achieved a 30% to 70% gain in sensory processing, motor accuracy, motor control, posture, strength, and range of motion. In the second patient, objective improvements were noted in the organization of the evoked somatosensory induced responses of the skin of the hand. s7 The question is whether these two independent cases represent a unique occurrence or whether controlled sensory discriminative retraining is an effective method of restoring motor control in patients with known occupational hand cramps. The purpose of this prospective, planned, follow-up study carried out in the context of clinical care was to evaluate the effect of sensory discriminative training in terms of sensory processing and motor control when this training is paired with more traditional therapeutic exercises to facilitate rela xation, reduce neural tension, and facilitate flexibility, strength, and fitness.

METHODS Subjects Twelve patients were admitted to this study. To be eligible, the patients had to be referred to the Peter Ostwald Health Program for Performing Artists and the Faculty Practice of the UCSF Graduate Program in Physical Therapy. Each patient had to have a diagnosis of focal hand dystonia as determined by a neurologist. Each patient was employed in a job that required high levels of repetitive fine motor movements of the hands. The patients included men and women between the ages of 21 and 55 years. Preferably, the patients lived in the San Francisco Bay area. If not, they had to be available for treatment at least once a week. One patient was from New Zealand, and one was from Australia; both came to the United States for a defined period of treatment of 6 to 18 weeks. This study was approved by the Committee on Human Research at the University of California, San Francisco. All patients reviewed the study protocol and gave informed consent prior to participation.

Four men and eight women with a median age of 35 years participated in the study. They had been diagnosed with dystonia between one and five years prior to this treatment intervention study. A neurologist completed a comprehensive clinical neurologic examination on each patient prior to referral for physical therapy. Each patient met the following clinical criteria for focal hand dystonia: •

Normal sensation of light touch, ability to distinguish sharp from dull, no areas of anesthesia

•

Normal strength and normal deep tendon reflexes

•

Demonstration of specific motor skills impaired by errors in timing, force, or trajectory, with stereotypical tonic postures and cramping sensations during the performance of a specific target task; which were absent at rest

•

Abnormal, uncontrollable flexion or extension movements of the digits and the wrist, which occur when trying to execute a specific motor skill within a characteristic context (e.g., writing with a pen or pencil, playing a musical instrument, entering data, typing)

•

Impaired function as a result of degraded movement

•

Skill loss that cannot be explained by a decrease in practice or time spent performing the task

•

Persistence of the abnormal movement despite resolution of any inflammatory, neuropathic, traumatic, or myopathic abnormalities'"

All the patients with focal hand dystonia were right-handed. In four patients the dystonia manifested in the right hand, and in eight it manifested in the left. None of the patients had surgery for the dystonia, and none had received botulinum toxin . Eight patients were working at the time therapy was.initiated. Five patients were musicians, one was a nurse anesthetist, two were physicians with writer's cramp, one was a data-entry clerk, one worked as a word processor, one was a business administrator, and one was a doctoral studen t.

Procedures All patients were measured at least twice, at baseline and after treatment. Test administration time averaged 1.5 hours. Testing was completed by a trained research assistant. Tests were not administered by the treating physical therapist. Sensory discrimination was measured using selected subtests from the Sensory Integration and Praxis Test (SIPT, Western Psychological Association, Los Angeles, Califomial/" All sensory tests included a stimulus of adequate threshold to be received, discriminated, interpreted, and acted on in a manner that could be measured. Each test component included multiple trials October-December 2000 291

delivered to a defined regional site (e.g., digits, palm, dorsum of hand). Three subtests were selected as the dependent variables for measuring discriminative tactile sensation-localization, graphesthesia, and kinesthesia. 31,32,60 These sensory tests were grouped into two levels of tactile processing: 1) those primarily involving a motor response to a tactile stimulus to show recognition of a body part, location of a tactile stimulus, or replication of a position in space (localization of tactile stimuli and kinesthesia); and 2) those requiring interpretation and replication of tactile stimuli applied to the skin (graphesthesia and stereognosis as measured by the key test designed for this study). Normative values for the SIPT have been established on children, and the test is used primarily to evaluate basic sensory and motor skills in patients with neurologic deficits. The test has reported validity based on congruent findings with other developmental tests. 60 Interrater reliability is reported as 0.95 or higher for all the subtests. Test-retest reliability is somewhat variable. Although none of the tests met the target of 0.9 reliability, all tests had either moderate (0.50-0.75) or good reliability (>0.75).60 This level of reliability is consistent with individual variability in sensory testing, based on environmental and internal factors (e.g., noise, motivation, attention, diet, and illness). For the three tests reported to have moderate reliability-localization, kinesthesia, and graphesthesia-a test-retest pilot study was carried out with ten adult patients. The test and retest were completed one week apart. Test-retest correlation coefficients based on the Pearson correlation coefficient were high (r loC = 0.92, rkin = 0.90, r = 0.91). When the mean difference scores were analyr~ using the paired Wilcoxon test, no significant differences were found on the repeat test of kinesthetic processing, but significant differences were found on the second measurements of localization (z < 3.69) and graphesthesia (z < 3.28). On the repeat localization task, the patients continued to be off target, by approximately 0.5 mm more than on the initial test. On the graphesthesia test, the patients were likely to get an average of one more parameter correct when replicating the target designs. Since no indications of learning and no other standardized tests were available, both the test for localization and the test for graphesthesia were kept in the battery. When the test required the patient's eyes to be closed, a blindfold was used to protect against eye opening for confirmation of test performance. For the key test, the patients were shown a picture of six different keys and given a key ring with the matching keys." The patient was asked to find the pictured key from the ring of keys, using one hand to hold the keys under the table and the second hand to search the keys. The time to find each key and the accuracy were recorded for all six keys. The patients were tested on two different forms of the test. In a 292 JOURNAL OF HAND THERAPY 2000

preliminary study prior to the intervention study, the test-retest reliability of the key test was found to be 0.92 and was significantly correlated with the manual form test (r = 0.76). These tests were consistent with those included in the in-depth clinical neurologic examination of adults. 62 The physical performance parameters of strength, range of motion, posture, neural tension, and balance were measured. A hand-held dynamometer was used to measure the strength of the lumbrical and interosseous muscles and the strength of the flexor digitorum profundus.f and a ratio of the lumbrical! interosseous (intrinsic) strength to the flexor profundus (extrinsic) strength was subsequently calculated. The measurements were taken according the procedures outlined in Kendall et al.,63 with the emphasis on testing the intrinsic muscles by extension of the interphalangeal joints with the metaphalangeal joints flexed to 90°.61 The Jamar dynamometer was used to measure grip strength. The arm was kept at the side with the elbow at 90°.64 Passive range of motion of finger abduction, forearm pronation/supination, and shoulder internal and external rotation were measured according to standardized procedures outlined in Norkin and White. 65 A checklist for postural landmarks based on the alignment with gravity63 was used to assess postural alignment from the side and posterior perspectives. Each landmark was assessed on an ordinal scale on which 0 indicated "no" and 1 indicated "yes." The total possible score was 19. The actual score was reported as a percentage. Neural tension was measured on an ordinal scale based on the work of Butler. 22 This scale was used to rate the patient's report of tension as controlled stretch, from proximal to distal, was placed on the brachial plexus. The patient was placed in the supine position with the elbow at 90°. The examiner performed the following movements sequentially: shoulder depression, shoulder abduction, shoulder external rotation, forearm supination, wrist/finger extension, and elbow extension. Tension was considered abnormal if reported by the patient before the end of the range of motion of each joint in the sequence of testing or asymmetry between sides. For each movement, a score of 4 indicated no tension reported until the very end of the range; 3, tension reported near the end of the range; 2, tension reported in approximately the middle of the range; 1, tension reported in the early part of the range; or 0, tension reported at the beginning of the range. Balance was measured with the patient's eyes open and with them closed. 62 Performance was scored on an ordinal scale. The patient was asked to stand in a stable position with eyes open and then closed for 20 seconds. Then the patient was asked to stand on one foot with eyes open and then closed for 10 seconds. Finally, the patient was asked to stand in a tandem Romberg

position (heel to toe) with the eyes open and then closed for 10 second s. Each sequence was rated as 2 if the patient completed it correctly or 0 if the patient was unable to complete it in the specified time period. Pain was measured using a visual analog scale. 66 Patients were asked to rate their pain on a scale of 0 (no pain) to 10 (the worst pain imaginable) in the affected arm, the unaffected arm, and the spine. The patient was to rank the pain when at rest, when walking, when performing the target task, and when performing activities of daily living. The scores were converted in a positive direction and summed to provide a total pain score, with a high score being no pain and a low score being severe pain. This was consistent with the other scoring, where a high percentage score was good and a low score was poor. Motor accuracy was measured using the motor accuracy test from the Sensory Integrative Praxis Test. 60 The time required to trace a line was recorded. A percentage score was then determined, which represented the distance the patient kept the pen on the target line divided by the total distance that the drawn line was actually on the line. Motor control was scored on an ordinal scale designed for patients with upper extremity dystonia. The patients were videotaped while they performed the target task. Multiple reviewers applied an ordinal scale to videotaped recordings of the patient's hand movements. This analysis included posture of the hands, fulcrum of movement of the hands, and the presence of involuntary movements while the target task was performed. Three physical therapists or physical therapy students completed the motor analysis scale for each patient. The evaluation instrument was then modified to retain the items with the greatest agreement between raters. This instrument (Appendix) continues to be evaluated for validity and reliability. Functional independence was measured usin the CAFE 40 Functional Profile of Independence" and the Rivermead Test of Independence.f The CAFE 40 had a test-retest reliability of 0.92. Work status was scored on an ordinal scale from 0% to 100%, in which 100% indicates that the patient is employed full time in the original/same job; 90%, employed full time in a different but same type of job or minor modifications of the original job; 80%, employed 75% to 80% time in the original job; 70%, employed 75% to 80% time at same type of work with minor modifications of original job, or 100% in a different job; 60%, employed 50% time in same job; 50%, employed 50% time different job; 40%, employed 25% to 30% time in original/same type of job; 30%, employed 25% to 30% time, different job; 20%, employed 20% time, original/same type of work; 10%, employed 20% time, different job; 5%, not employed but active in school or doing volunteer work or very occasional employment; and 0%, not employed and not active.

f

INTERVENTION Traditional Intervention All patients were instructed in a home program includ ing posture exercises, neural mobilization, strengthening some of the intrinsic muscles of the hand (the lumbrical and interosseous muscles), practice in ergonomically safe use of the hands, 56 and a fitness routine (e.g., walking, stationary bike riding, or running) .

Sensory Discrimination Retraining A comprehensive sensory discrimination rehabilitation program was developed to restore the subject's sensory processing accuracy. Supervised physical therapy sessions of I to 1.5 hours each were held one or two times a week. However, the patients were asked to reinforce sensory retraining activities at home. To facilitate compliance, the patients were asked to keep a log of their exercise routine at home. The sensory discrimination retraining was based on principles of neural plasticity and psychophysics. Attended, repetitive, non-simultaneous sensory stimulation tasks involving stimulation of the mechanoreceptors, muscle afferents, and Golgi tendon organs were practiced during supervised treatment sessions and at home. The sensory tasks were designed to restore the sensitivity of the individual receptive fields of the affected hand and fingers, with the objective of re-differentiating the somatosensory map of the hand. If the patient failed to identify the stimulus accurately, the stimulus was repeated until the patient was correct. Either the stimulus was made larger or the patient was allowed to look while the stimulus was delivered, and then it was repeated again with the patient's eyes closed . The therapists provided feedback to reinforce correct performance and learning. The patients were expected to complete at least one or two hours of sensory discrimination activities each day at home. The tasks involved high levels of attention, with some type of decision required. The sensory tasks were performed by the patient in different positions (e.g., supine, sitting, prone), with the arms in positions that were different from those used during the target tasks (e.g., arms at the side or in full elevation) . The tasks tapped skills of localization, graphesthesia, and stereognosis. The sensory discrimination activities included 1) identifying sensory stimulation of the skin with varying textures and temperatures; 2) identifying various objects and designs drawn on the hand and fingers; 3) reading Braille with one finger and playing games with Braille cards (with the eyes closed); 4) identifying shapes, letters, and numbers pressed or drawn on the skin; 5) playing dominoes and determining the match with the eyes closed; 6) identifying matched pairs of objects either in a game format or by matching objects drawn October-December 2000 293

TABLE 1. Performance of Patients with Repetitive Stress Injury-Focal Hand Dystonia (FHD) Before and After Treatment: Affected Side Mean: Patients w ith FHD Criteria Motor: Mo tor con tro l (%) Motor accuracy (%) Mo tor accu racy time (sec) Ph ysical: Grip st re ng th (lbs) Lumbrical/ in terosseous strength (lbs) Flexor p rofundus stre ngth (lbs) Rat io: intrinsic to ext rinsic strength Range of motion (ROM) : Abduction (0) Pronation (0) Supination (0) Int ern al rotation (0) External rotation CO) Total ROM (%) Neural tension (%) Pain-arm (%) Sensory: Local. pron ati on (ern) Local. su pin atio n (ern ) Two-p oint discrimination (m m ) Graphesthesia (%) Kinesthesia (ern) Key test (%) Key test time (sec) General: trunk: Spine pain (%) Posture (%) Balance (%) ADL (%) Indep endence (%) Work status (%)

Normal Subjects (L)

Before Treatment

After Treatment

79.9 32.5

47.1 70.4 80.0

78.6 84.7 71.5

31.4 14.3 -9.0

(14.4) (15.1) (28.8)

7.82 3.42 NS

s 0.00001 s 0.00034

78.0

77.5

84.1

6.6

(9.0)

2.65

s 0.0040

1.5 7.0

2.1 5.9

3.0 8.0

0.9 2.1

(0.74) (2.7)

4.29 2.8

s 0.00001 s 0.0026

22.3

40.6

54.8

14.2

(16.1)

3.18

s 0.00074

45.4 86.8 88.3 94.2 89.0 86.0 95.5 98.1

33.5 76.1 80.0 66.5 76.5 70.7 67.2 82

39.7 81.7 81.3 70.1 81.6 85.6 90.4 93.2

6.2 5.6 1.2 3.6 5.1 14.9 23.2 11.2

(6.66) (8.7) (7.8) (14.0) (13.2) (16.2) (15.1) (12.7)

3.37 2.32 NS NS NS 3.32 5.54 3.18

s 0.00038 s 0.0102

1.1 0.8 3.3 62.6 1.6 63.4 37.0

1.9 2.2 3.4 63.4 3.2 49.9 98.4

1.0 1.3 2.8 82.6 1.7 71.7 77.1

- 0.9 -0.9 -0.6 19.2 - 1.5 - 21.8 -21.3

(0.78) (1.05) (- 0.28) (15.1) (1.69) (31.69) (21.56)

-4.2 -3.2 -7.3 4.6 -3.2 - 2.5 - 3.6

96.3 94.5 99.2 ' 100.0 89.6

89.0 78.8 81.2 100.0 77.8 68.5

99.0 87.5 90.2 100.0 87.5 76.2

10.0 8.7 9.0 0 8.6 7.7

(13.4) (12.47) (12.1) (0) (11.9) (19.6)

2.7 2.5 2.7

s 0.0036 s 0.0060 s 0.0036

2.6 NS

s 0.0047

Mean Difference (SD)

t Test

Significance

NS

NS NS NS s 0.00045 s 0.00001 s 0.00074 s s s s s s s

0.00001 0.00069 0.00001 0.00001 0.00079 0.0068 0.00016

NS

N OTE: L indicates left; NS, not sign ificant. • All normal subjects were students.

from a bag or a box full of rice, beans, or noodles; 7) identifying raised letters and numbers; 8) searching for shapes to place in a matched opening; 9) discriminating and matching coins, beads, buttons, shapes, and small animal figures; and 10) asking the patient to locate the point on the skin where they felt they were touched. Sensory motor retraining activities were integrated with the sensory retraining . For example, biofeedback was used to help patients eliminate the cocontraction of the flexors and extensors and to qui et unnecessary motor contraction. Patients were asked to hold and palpate the target instruments, but not to play the instrument until the involuntary mo vements were controlled. Patients were also asked to do simple sensory and motor tasks while using a mirror. The mirror was placed between the affected and unaffected sides. The patient was asked to focus on the mirror image of the unaffected side. This mirror image looked like the affected side. The first goal was to make the 294 JOURNAL OF HAND THERAPY 2000

affected hand look like the mirror image. This included placing the hand in a functional position without hyperextension of the interphalangeal joints. Then the patient was asked to perform fine motor activities-like picking up objects, using a pen, or tapping individual fingers-while concentrating on making the affected hand perform just like the mirror image of the unaffected side. These activities reinforced the restoration of normal sensory awareness and motor control. In addition, the patient wa s asked to spend at least 30 minutes a da y imaging normal sensory processing, normal motor control, and effective, efficient execution of the target task. In this way, the patient was asked to integrate normal sensory processing and motor control by performing the target task mentally without abnormal involuntary movements. This technique also facilitated the integration of normal sensation with normal perception and reinforced the confidence of restoring normal function.

TABLE 2. Performance of Patients with Repetitive Stre ss Injury-Focal Hand Dystonia (FHD ) Before and After Treatment: Unaffected Side M ean: Patients with FHD Criteria Motor: Motor control (%) Motor accuracy (%) Motor accuracy time (sec) Physical: Grip str ength (Ibs) Lumbric al/inteross eous strength (lbs) Flexor profun dus strength (lbs) Ratio: intrinsic to extrinsic strengt h Ran ge of motion (ROM): Abd uction (0) Pronation (0) Supination (0) Internal rotation (0) Extern al rotation (0) Total ROM (%) Neur al ten sion (%) Pain-arm (%) Sensory : Local. pronation (em) Local. supination (em) Two-point discrimination (mm) Graphesth esia (%) Kinesthesia (em) Key test (%) Key test time (sec)

Normal Subjects (R)

Before Treatm ent

After Treatment

Mean Difference (SD)

Test

Significanc e

74.5 14.9

77.8 76.9 79.5

87.7 88.2 84.7

9.9 11.3 6.1

(13.4) (16.2) (19.7)

2.66 2.51

-s 0.0039

NS

NS

70.9

78.5

84.6

6.1

(7.7)

2.84

:< 0.0023

1.5 6.9

2.4 7.4

3.0 8.6

0.5 1.1

(0.8) (3.2)

2.5

s 0.0062

NS

NS

21.6

47.7

48.8

2.6

(24.5)

NS

NS

45.6 87.4 87.8 92.6 85.9 88.0 97.0 98.0

39.2 80.0 82.0 69.3 76.3 83.7 75.4 97.5

40.2 83.0 84.3 75.8 80.4 89.5 95.4 100.0

NS NS NS

NS NS NS

1.96 2.0

:< 0.0228

1.0 0.7 3.3 58.6 2.3 60.0 40.6

1.7 1.6 3.3 66.7 2.5 66.6 107.4

0.8 1.2 3.2 80.5 1.8 77.8 71.4

1.02 (6.36) (6.9) 3.2 (7.2) 2.7 7.6 (14.0) (7.7) 4.2 5.7 (15.8) 20.0 (20.8) (6.2) 2.5 -0.9 -0.5 - 0.1 13.9 - 0.8 11.1 - 36.0

(0.58) (0.70) (- 0.4) (21.4) (1.39) (22.4) (48.6)

t

" 0.0060

:< 0.0250

NS

NS

3.47

:< 0.00028

NS

NS

-5.25 -2.31

NS 2.4 -1.92

NS -2.7

:< 0.00001 :< 0.00069

NS :< 0.0082 :< 0.0274

NS :< 0.0035

NOTE: L indica tes left; NS, not signi ficant. • All normal subjects were students.

Research Design and Data Analysis This was a planned, pre-experimental, pre-and posttest design using one group of patients. This was a pilot study, with the treatment program incorporated in the traditional health care delivery system under covered health care benefits . When patients exceeded their covered benefits, they were treated without charge to complete the 3- to 6- month treatment period. There was no control group. However, each patient's unaffected side served as a reference for change with re-testing, although results were potentially confounded by the possible central crossover effects between hemispheres. In addition, normative data were provided for reference. Multiple dependent variables were measured to capture the complexity of performance variables that could affect motor control. The dependent variables were 1) sensory discrimination (localization, graphesthesia, kinesthesia, stereognosis), 2) physical performan ce (strength, range of motion, posture, neural tension, pain, po stural righting), 3) motor control (including video analysis of involuntary movements and motor accuracy), and 4) functional independence. All variables were measured at baseline and after the completion of treatment. All patients were treat-

ed for a period of three months. All the dep endent va riables included multiple trial s to make it po ssible to establish a score . Thus, although the total number of patients was small and some of the d ata were ordinal, based on the central limit theorem, the paired Student t test was considered appropriate for the statistical analysis of differences. Each of the dependent variables was considered an independent family and tested at p < 0.05. The an alysis was done on the affected and unaffected sides, w ith each analysis for each sid e cons idered a separate famil y.

RESULTS All patients who agreed to participate in the study completed the study. Tables 1 and 2 summarize the changes in performance on the affected side (Table 1) and unaffected side (Table 2) for all the dependent variables. Initially, patients with focal hand dystonia did not perform as well as controls in motor accuracy, motor control, and sensory processing. Finger spread and forearm pronation were also reduced in these patients . On the affecte d side (Table 1), there were significant gains in the po st-treatment measurements of th e physical parameters of pain , posture, balance, neural tension, strength, and range of motion (Figure 1). October-December 2000 295

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FIGURE 1. Change in physical performance parameters on the affected side. All pre- to post-test comparisons are significant at p < 0.05. White columns shoui control values; gray columns, pretestvalues;black columns, post-test values. liP indicatesintrinsicto-extrinsic (profundus) muscle strength;ROM, range of motion.

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FIGURE 2. Change in sensory variables- localization on the dorsal and glabrous surfaces (/ocal-P and local-S, respectively), kinesthesia, and two-point discrimination-s-on the affected side. All pre- to post-test comparisons are significant at p < 0.05. White columns show control values;gray columns, pre-test values; black columns, post-test values. 100 ,....--

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FIGURE 3. Change in sensory variables- graphesthesia and stereognosis as measured by the key test accuracy and time-s-on the affectedside. All pre- to post-test comparisons aresignificant at p < 0.05. White columns show control values; gray columns, pre-test values; black columns, post-test values.

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These gains brought the measured performance of those with dystonia up to levels similar to those of control patients, except for limitations in finger abduction, which did not change significantly . In terms of sensory processing, significant gains were measured in localization, graphesthesia, kine sthe sia, and stereognosis (Figures 2 and 3). In some cases, after treatment, those with focal hand dystonia performed better than reference control patients. For motor processing, patients with focal hand dystonia also had significant gain s in motor control, but performance was not 100% (Figu re 4). Motor accuracy increased significantly and was similar to that of controls, but there were no significant gains in speed of performance. Thus, those with dystonia continued to perform slowly on this task, compared with a reference group of healthy subjects. On the unaffected side (Table 2), the clinical measurements of physical performance parameters and motor control for the patients with dystonia were similar to those for controls, except that the patients with dystonia were slower on the motor accurac y task. For example, the lumbrical and interosseous muscles were stronger in the patients with dystonia than in controls, and the ratio of intrinsic to extrinsic muscle strength was higher (47.7% compared with 21.6%). When comparing initial sensory processing on the unaffected side with reference controls, the patients with dystonia had reduced skills in localization and were slower on the stereognosis task (key test). After treatment, the performance of patients with dystonia was similar to or better than reference controls on all parameters, but the patients with dystonia remained slower in both the motor accurac y and the stereognosis tasks . In activities of daily living, there were no significant differences between baseline measurements for reference controls and the patients with dystonia. However, the patients with dystonia complained of more back pain, and their posture scores were significantly lower. Although both the healthy reference group and those with dystonia were independent, as indicated by measurements of activities of daily living, those with dystonia did not score as high on functional independence and quality of life. After treatment, however, patients with dystonia made significant gains, and their scores for back pain, po stural alignment, activities of daily living, independence, and quality of life were similar to the scores of the reference control. All but 2 of the 12 patients had returned to work by the end of the treatment period.

Accuracy (%)

TIme (sec)

FIGURE 4. Change in motor variables- motor control, motor accuracy, and time to complete motor accuracy test-i-on the affected side. All pre- to post-test comparisons aresignificant at p < 0.05. White columns show control values; gray columns, pre-test values; black columns, post-test values. 296 JOURNAL OF HAND THERAPY 2000

Our hypothesis is that repetitive, closely attended, rapidly sequential stereotypical or simultaneous motor movements can lead to a breakdown of orderly representation in the somatosensory cortex. In some

patients, this may be severe enough to lead to a problem of motor control. In this study, patients with severe RSI-FHD demonstrated significant problems in sensory processing, motor control, and selected physical parameters. After a sensory discrimination retraining program for three to six months, 80% of patients showed significant improvement, which ranged from 30% to 70%, depending on the parameters. All but two of the patients returned to work. This suggests that a comprehensive physical therapy program that includes sensory discrimination training can enhance function and return to work. If a person perseverates on a task that is Hebb-like69 (e.g., coincidence-based) and also requires substantial attentional focus with nearly simultaneous stimulation of adjacent fingers, a disorganization of the somatosensory cortex could occur because of unusually large, overlapping cutaneous receptive fields. This could interfere with the normal sensorimotor feedback loop and with motor control. In lower mammals, the attentional focus has been shown to accompany an increase in acetylcholine levels ./" Enhanced acetylcholine release has been shown to be requisite for cortical change following nerve section.71,72 The behavior of rapid sequential, attended goal-directed activities presents an ideal substrate for cortical map reorganization. If the loss of motor control is associated with degradation of the somatosensory cortex, it could explain why the current treatment targeting a reduction in cramping through local botulinum toxin injections73-75 provides local quieting of the cramping muscle but does not restore normal motor control of the hand. This learning hypothesis of RSI-FHD is strongly supported by electrophysiologic mapping studies in nonhuman primates and by magnetic imaging studies in human beings. In two clinical research studies,31,32 patients with RSI-FHD were found to have problems with graphesthesia and stereognosis. Patients who had repetitive stress injury with tendonitis but without motor dysfunction were found to have problems of kinesthesia or localization. Sensory degradation following coincident stimuli has been noted in other, related experiments with owl monkeys. In primate studies by Wang et al.,75,76degradation of the electrophysiological representation of the hand was measured after a training paradigm in which the monkeys received coincident tactile stimulation to the proximal and distal segments of digits 2, 3, and 4. The multiple receptive fields and the overlaps were measured only in the stimulated segments. Similar findings have been documented in human subjects trained in this same sensory task. In this case, differences in the density of the somatosensory representation of the trained d~its could be measured by magnetic source imaging," 78 which is consistent with changes in sensory representational overlap resulting from training. Thus, the focus of clinical treatment must be to determine the appropriate treatment strat-

cgy to restore the somatosensory representation of the hand. In contrast, in one primate study,33 a monkey refused to use an articulated hand strategy to open and close a hand piece. Instead, he used an extremely variable shoulder pulling strategy. This monkey worked more slowly than other monkeys (approximately 9 repetitions per minute instead of 20 to 30 repetitions per minute) and required two training sessions a day to meet the target of 400 to 500 trials per training session. The monkey did not develop signs of focal hand dystonia, and the somatosensory map was only slightly degraded/" The repetitive behavior of proximal arm pulling does not meet the input coincidence requirements for degradation. Similar types of somatosensory degradation have been reported in a study of patients with chronic back pain. Flor et a1. 79 studied patients with a long history of low back pain. She demonstrated a measurable degradation in the sensory representation of that area of the back. This suggests that chronic pain can also lead to sensory degradation. Although specific dystonias have not been reported in patients with chronic back pain, problems in motor control have been reported in patients with severe chronic pain, like that of reflex sympathetic dystrophy.f" However, sensory degradation alone may not be the only concern in treatment of patients with focal hand dystonia. Two recent studies suggest that biomechanical limitations ma y be risk factors for the development of focal hand dystonia in patients who do high levels of repetitive work. Wilson et al.26 reported that musicians who developed hand dystonia showed clear asymmetry in passive finger spread in the central digits and limitations in forearm and shoulder rotation on the affected side. This lack of finger spread was also measured in this current study and was documented in an anatomical study by Leijinse.24 Such limitations force musicians to play their instruments with their hands and digits in awkward end-range postures. These postures would also require the patient to exceed their comfortable range while performing highly demanding repetitive tasks. Such stress in the face of a pre-existing anatomical limitation in motion could be a significant factor in the ultimate development of a dystonia. As studies in Germany have shown,81 genetics ma y also pla y a role in the genesis of focal dystonia. However, in these studies, none of the subjects with an autosomal dominant inherited gene with low penetrance had focal hand dystonia; instead, all had cervical dystonia. In a genetic analysis of Ashkenazi Jewish patients with focal hand dystonia, Gasser et al.82 did not locate the DYTI autosomal dominant gene that is typically found in this cultural group with generalized dystonia. Even if a gene was identified in patients who developed focal hand dystonia, it is conceivable that high levels of repetitive, skilled October-December 2000 297

hand use could still degrade the somatosensory representation of the hand. Effective treatment could still be sensory retraining.

CLINICAL IMPLICATIONS Although recent studies report somatosensory disorganization in human patients with RSI-FHD, no controlled studies have been reported on the effectiveness of sensory discrimination training programs focused on restoring the normal somatosensory representation of the hand to improve motor control. It is also not clear how severe somatosensory de-differentiation must be before it leads to motor dysfunction. Further research is needed to determine if it is possible to restore the normal somatosensory representation of the digits with clinical sensory discrimination training and whether restoration of the somatosensory representation would be sufficient to restore normal motor control. This question could be studied in non-human subjects by implanting an electrode in the primary sensory cortex. The primate could then be trained to perform a highly repetitive task requiring near simultaneous stimulation of adjacent digits. Changes in the somatosensory map could be measured and correlated with change in motor function. In human patients with RSI-FHD, magnetic resonance imaging and magnetic source imaging could be used to determine the somatosensory organization of the hand in area 3b. Ideally, documentation of the hand representation before and and then after the initiation of a sensory discrimination training would be another way to measure the effect of training on structure. Based on the reports of non-human and human primate research, clinicians should carefully evaluate sensory processing skills in patients with severe repetitive strain injuries, particularly those who have signs of focal hand dystonia. Therapists should keep careful records of sensory training activities and the effects of such training on somatosensory skills and motor function. Another question that must be raised clinically, is where to target the sensory retraining and what parameters of sensory stimulation need to be met. If all of the digits showed sensory degradation in nonhuman primates with signs of focal hand dystonia, would it mean that all fingers must be equally stimulated? However, some research studies suggest that the sensory degradation can. be specific, involving primarily one digit with some carryover degradation to adjacent digits. In these cases, then it would logically follow that the clinician should begin the sensory retraining on the most involved digits. Relevant to the question of where to focus sensory retraining, Nagarajan et al (17), recently reported that human subjects could improve temporal processing of coincidence based somatosensory stimuli with training. Using two non-coincidence based vibratory stimuli, he 298 JOURNAL OF HAND THERAPY 2000

trained subjects to be able to detect two stimuli placed closer and closer together and showed that individuals could improve their discrimination. He also demonstrated that learning achieved in one trained finger could be transferred to an adjacent finger. He then demonstrated that there were carryover effects to the somatosensory discrimination of the digits following auditory training. Furthermore, these researchers demonstrated that the somatosensory changes were measurable by functional magnetic imaging. If these findings can be abstracted to the clinic, it would suggest that the clinician could expect gains in sensory discrimination beyond the target digit stimulated. In addition, it might facilitate sensory reorganization if discriminative training included other modalities and not just superficial cutaneous receptors. In particular, it might be important to engage the muscle afferents and golgi tendon organs in sensory discrimination.

STUDY CONSTRAINTS This study provides exciting validation of one type of sensory retraining for patients who perform jobs with highly repetitive movements and develop a motor problem referred to as focal hand dystonia. However, the study had some constraints, limiting the generalizability. The most serious constraint was that there was no control group to balance the potential Hawthorne effect (81) and to document the extent of learning that might have occurred with retesting alone. In addition, the measurement tool used to document voluntary control was not standardized. However, in this study, the unaffected side was used as a control and the measurements were made by a research assistant, preventing bias in measurement. In addition, the evaluation tool has been used on a variety of subjects and the evaluation was applied by different therapists and physical therapist students and the variability in scoring was less than 5%. Another constraint in this study was the fact that many patients with focal hand dystonia did not live in the area, and it was difficult to get third-party payers to reimburse them for the 12 to 24 visits. Clearly, a multicenter study with a randomized, crossover clinical design is needed. 83 This research must be supported by extramural funds to eliminate the problems of reimbursement for treatment. Ultimately, if there is evidence to support our practice, then it may be easier to obtain prior authorization to treat patients with complex hand problems. Further, in terms of sensory retraining, it may ultimately be possible to develop computerized sensory stimulators to increase the efficiency of retraining.

CONCLUSION Several conclusions can be drawn from this study. Repetitive, rapid, alternating movements of the digits can be associated with a loss of motor control. Signs of somatosensory degradation can be meas-

ured in these patients using common clinical tests. Significant improvement can be measured in sensory processing and motor control following an intensive sensory retraining program. Improvement can be expected bilaterally. It is unlikely that 100% recovery will be reported in 3- 6 months. Computerized technology which increases the intensity of the repetition and the gradation of the sensory decisions could possibly shorten the retraining time and keep the tasks more interesting.

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ApPENDIX

Motor Analysis Scale

Name

Dates

Digits involved ~_

Date

_

Analysis of Hand Movements:lnstrumenUComputer Datc I.

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RIGHT

Circle onr;ate-- -LEF T

RIGHT

Date

LEF T

",",,-,

Yes (0) No (l) Yes (0) N0l l ) 3. UK-S wri)( ud ial hJIlUl de....MN:lr\ Yn (O) No (2 ) VesCO) No (2 ) Yes lO) No (2 ) Ves CO) No( l ) 4 Ae~s andell lt!\:fs eltlG\.1 VeS(2 ) No (0) Yu{2} No (0) Ves (1) Na (O) Yes (2} No {O) S .ROOltnrQR.amlt~)yes (2) No lO) Yes 12) No (0) Yes (2) No (O) Yes (2) No lO) 6. tlcse:sOlOOu'tndssbou1dc:r YeI (l ) N0 lO) Ves (2) No lO} Yes (2) NOlO) Ves el ) No lO) 7.Adductliand introtatesshouldtt YU (2) NolO) Yes (2) No (0) Ves (2) No (O) Ves (l ) Na (O) 8. Hib, shoulder Yes (0) No (2) Yes (0) No (2 ) Yes (0) No (2) Yes (0) No (2)

IL OnraD Ap pearpcc (balUK:c)

VesCO) No(2) Ves cO) No ll)

Yes(2) No(O) Yes (2) No (O) Yc:sQ)No (O'J Yes(2) N o(O ) Yes (0) No(2) Yes (0) No (2) Yes (0) No (2) Yes (0) No (2) Yes (2) No (0)

Yes (t) Yes-(2) Yrs (2} Yes (2) Yes (0) Yes (0) Yes (0) Yes (0) Yes (2)

No (O) Na (O) No (0) No (0)

No(2 ) No (2J No (2) No (2) No (0)

III .Ab oo r m a l/lavohmtary Mo vem en ts : (99 ) Sc. l ~s :

Frequenc )' Stv er lt y : Quol lly , Spmi:

NA(O)llOl ~prilllC ( l )AJJtbc limc NA (O) aoI: "f'I"'I'PriI&C (l) ~ NA (O)aoI:~ (I)P'ta

NA (G) _IIpIlf'llIll'We (1)Ycryoo.w

NA 1 2 3 4 NA 1 2] 4

NA 1 2 3 4 NA 12 3 4

NA 1 2 1 4 NA1 23 4

HAl 2 3 4 NA 123 4

NA I 2 ] 4 NA 1 23 4

NA I 2 J 4

NA I 2 ] 4

NA I 23 4

NA 12) 4

NA I 2 34

NA I 2 ) 4 NA I 2 ] 4

NA 12 34 NAl 23-&

NA 1 13 4 NA I 1) 4

NA 12 3 4 NAI 2 34

6. Inlensioll a-cmor n0te4 with putposd ul mO~meDu. Ftujoency NA I2 34 Severity NA l l )4

NA I 2 ] -& NA I 2 3 4

NA l 23 4 NA l23 4

NAI 2 34 NAI 2 34

end raJ1il= movements (hyperextension) notedwben finger pre551CSdown a.lPjoint!lhyperelltend NAI 2 34 NA I 2) 4 b. MP joints excessivelyextend NAI 23 4 NA I 23 4

NAl 2 3 4 NAI 2] 4

NAl 2] 4 NA I 2) 4

e. Wm t lJocootroUably extends

",""""", Severity

4. Arrllythmie move ments obsen cd quality

(2)Somc l.>fthc uror: (3) Ocus ionally (4) N(lIIpI'CIe!II (2) M~ly ....~ : { 311otiId 4)NOI prW:nl (2) PlIil" i)IOood (4) & ocllelU. (2) Moderucl y SloMr (3) Milllly 510"'""" (4) ~ .. OIlIerss.lr

Severity

7,

-

NAI 2] 4

HAl 2 ] 4

NA I 2] 4

2 Able to do rapid. c:oordinatodaltematillg movemenu (e.g. qu.Jityof trill) NA I 2] 4

NAt 23 4

NA I 234

NA I 2 34

NA 1 2] 4 NA I 2 34

9. Lack.of VOIWltary control on tuJc s ordter thaD target w k (self rqlO(1) NA 1 2 3 4 !'fA I 2 ) 4 to . Mou,e (20)

NA I :I J 4

NA I 2 ]

NA.1234 NA t 2 J 4

NA I 2 3 4 NA I 2 3 "*

NAI 2 J 4 NA12 ] 4

NA I 2 34 NA1234

NA 1 2 ] 4 NA1 2 3 4

b . Fingers uncontrollably extend _ _

MP or lP, whatfingcrs NA1 2]4 NA1 234

Fn:quency Severiry

Invol_oJ Hand

N .~,

NAI 234 NAI23 4

a. Reus and extends fingcn b Aellcs and exteods wrist I:,Radi ally / ulnarly devialt:s 'l(risl d. All fingenl"eitiojploWll e. Soncr....... brid ....y rn:a 1DOU8C f PingensqUCC:7.ingmOUK 8 WrisftutillgoodeHJpad 1\. Wrist floatinB offdesklpad i,Wrist atan angle(wnarlndial)

_ What (In, etS

NA I 2 34 NA J 2 J 4

( 148)

Involved

divU

NA 1 2 3
NAI 234 NA I 23 4

a.. Fingers uJJCOhG"Ollably f1e1l

NA I l l 4 NA I 2 J 4

4

NA 12 )4 NA I23 4

3. Iovolurlury movemeDlSllbscricd wbcDdoing w gel task.(c.g. dys:onie movemcnlS wben playing keyboard. instrume nt)

Se verity

~

b. UnconlTOllably extend

Severity

I. MOYemelltof involved M IClS d ower tha n u ninvolvedHde (spood) NAl 2 3 4

NA I 2

8. Involved fangers have uncontrollable movements when adjacent finger depressed e n swface a. Unc:onttollably flex mq~ncy NA1 23 4 NA i2 34 NA I2 3 4 NAI23 4 NA1 2 ]4 NA I 23 4 Severily

CIrck Ooe

~1

NA 1 2 3 4 NA 1 2 3 4

NAI 2 34 NA 12 34

5. Physiological tremor notod ilt rest: ",""""""

Yes (2) No {O) YU(2) No (0 Yu (2}No {0 Ye$( 2} No(O Ves CO) No (2 Yes (0) No (2 Ves CO) No (2 Yes (0) N o (2 Yes (2) No (0)

_ LEFT

NA I 2 ] 4 NA 1 2 3 4

Se\lCri ty

Yes (O) No (2 ) Yes lO) No (l )

of Haads duri_. Tuk Perf orm _c:e : (18)

l. fjnger5b~aucedband : Ye1 (2) No (0) 2. Fingen 3Ublc(oo lP byper ul} Yes (1) No(O ) 3. MP j1s ~labk (r.() b)'pcr c:d.) Yes (2)NotO) 4. Fingersrucingdown Yes (2) No(O) 5. Pincc rshooYmngovcruys Yes (0) No(2) 6. l ilnd Ioob claw like Yei (0) No (2) 1 . An:hc.sof hand appearflat Yes (0) No (2) 8. Thwn b adducted0( hyperext-DIP Yes (0) No (2) 9. Lightly touching key.,'in3lrulllC'lltYes (2) No (0)

Da«,

d. wen uncontrollably flexes

Date

1 .I~d'lil~tlaIMMJ'jtI Yu {O) No(2) 2. Uses 'Nri5tflcx ionandu.lulI,ion Yes (0) No(2)

_

Circle One RI GHT LEFT RI G HT c. Thumb uncontrollably adduces. or hypere1l.tellds at DIP joint """",,,,> NA 123 4 NA 1 2 34 NA 1 2 34 Severity NA 1 2 34 NA 1 2 3 4 NA 1 2 34

Yes (0) Yes (0) YU (O) Yes (2) Yes (O) Yu(O) " es (O) Yes(2) YCI.I(O)

No (2)

No (2) No(2) No (O) No(2 ) No (2) No (2) No (0) No(2)

Yes (0) No (2) Yes (0) No (2) Yes ( O) No (2.) No CO) No (2) No(2 ) No(2 ) No( O) N\l(l)

Total Rlgb l _Tnta l Left _ %

No (2) Yes (0) No (2) Ye.II (0) No (2) Yes (O) No (O) Yes (2) No (2) Ves CO) tfo(2) VesCO) No (2) Yes CO) No(2) YCfo(2) No (2) Ves (O)

No (2) No (2) No (2) No(O) No (2) No(2) No(2) No(O} No (2)

Toh l RilJ:hI _ Total Left _ %_ %

% -

Commenls

Datc_ _ _

_

Vn (0) Vn (0) Yes (O) Ve1O (2.) Ye1O (O) Ves CO) Ye, (O) Ves CO) Yn {O)

Yes (2) Yes CO) Ves CO) Yes (O) Yes (l ) Yes (0)

<4

Date

_

CirdeQne

RIGHT

Analysis of Hand Movements: Wri ting Datc_

_

_

Datc

_

Circle one: I. Fo ltrum or mo n lac . t: (t8 )

RI GHT

LEFI'

d.WrisllJnC lJIItroIlablyf1cxC5 ",""""", Se~C)'

RIGHT

LEFT

RIGHT

LE FT

NA I 2: 3 4 NA 1 2 ]
' NA I 234 NAI 2 ] 4

NA 1 2 3 4 NA 1 23
NAI 2 3 " NAI 2 34

NA.1 23 4 NA 1 2 3 4

NA 12 3 ..

NA 123 4 NA 1 2 3 4

NA 1 2 3 4 NA 123 ..

NA I 23 4

NA I 234

LEfT c. Wrilt uncontrollably e xtende

I. Writes by beQdinglstmightening fingers 2 Writes byfleliQgl e;o;lending wrist 3. wntes by radially/ulnarly deviates wrist 4. Writes by bending/straightening elbow ). Ple.r.ts anoJclIlellds sho uJd er u wri tes 6. Writes wilh finger.wrist,elbow/sh movt 7. Forearm mid supinationlpron, as wri tes S. Focc!ll"Dl. .da)' s pronalOdas writes 9. QlOO aJtn/sh ~ pa~ as Mila;

Yesta} No (2)

Yes (0) No (2) (0) No (2) Yes(O) No (2) Yes (2) No (0 ) Yes (2) No {O) Yes (2) No (O) Yes (2) No(O ) Ycs(2) No (O) Y cs (2 ) No (OI

Yes(O) No (2) Yes Ye, (0) Yes (2) Ye. (2) Yel (2) Yes (2)

No (2) No (O) No( O) No (0) No (0)

YU(2 )No(O )

Yet(2) No(O)

I .Heavily grips pen (hypcnx 5C'lldf DIP DlD2)Ycs (0) 2J..1P joi.nu colJap$CorDIPjointsnleDd V es CO) ) Fin gcrs lWy ~jn ldo*n m:lIX:Q Ves (2) 4.Some fingeh hoovmng ovu pen Yca (O) S.Writing is qutC:k andjert)'; pic ks up hand Y"' (O) 6.Writina iH tr.w th and relaxed Yea m

No (2) No (2) No (O) No (2)

Yes (0) Yes (0) Yes (2) YC5 (0)

VesCO) No (Z) Yes (0) No (2) Ye5(0) No (2) Yea;(2) No (0) Yes (2) NQ{O) Yes (2) No (0) Yes (2) Na (O) Yes( 2) No to) Yu (2) No tO)

Vn(O) No (2l VesCO) No (2) Yes (0) No (2) Yes (2) No (0) Yes (2) No (0) Ye~(2 ) No (O) YCi(2) No (O) Ycs (2 } No (O)

Yu (2} Ko (O)

:S0 (2 ) Yes (0) !'fo (2) No (2) Ves CO) No (2) N o {O) Yes (2) :40 (0)

Yes (0) No (2) Ves CO) No (2) Yes (2) No (O) No (2) y~ (O) S o (1) Yes CO) No (2) No (1 ) Va (0 ) Ko (2) Yes (O} NIJ(2 ) Yes CO, No ( 2) No (O) Yes (2 ) No (O) Y«(2) No,l(O) Ycs (2) No (O)

Il l .Ab no r mal or 1...oh!.n.t. Q M(lYt•• lltM (' 6) Sea lu : r n qu ellcy (0) NA not appropriare (I) A n lhe time: (2) Somf of (be ti/l'lC' (3) Qc(:lIIionaJ.ly (4) Nol prCSClIl

Sever it y:

(O} NA Jl(lII.~

Qual it y :

(O)NAIIOIapproprialC (I ) Pllo<-

S p~ci :

(0) NA nOlqrpruprialc

(I)

~

(I) ",,"10"' :

RIGHT

(2) Modenl:eIJ ... ~tn! :(l)Mi.ld Falr (3) 0000 (2)Modenl
CircltO..e LEFT

RIGHT

(4) NOIpre>cnt ~ 4)£xce[lenl

("jS_ both.

LEF T

""""''''' Seven ty

4. AtThythD1i' movements observed (q,lIality):N A I 2 3 4

NA 1 2 ) ...

NA 1234

NA I 234

2. Ha1ldtens«upusOOftutakesthepen NA I 2 ] "

NA I 234

NA 1 2 3 4

NA I 2 3 4

3. htvotunwy movemenlS obsCf'Ved wheIldoiDg ~ tuk (c.J . dystorlie lDOVUneflts)

A. F'Aget'Suno:;lJauoaa bly fk); Frtqumcy Severity

_ Wb at fi.e, el'1o NA I "2 ] 4 NAI 234

NA 1 2 ] of NAI2]4

b. Jli:nge:'1l UflCOfttrotla.bly exteod _ _ MP 01" IP, wh&t fillBC'f'S fn,quency NAl t 34 NAI234 Sevm ty NAI 234 NA1 234 c. Thumb U!Koutroiltbly adduc:ts. 01" byperutcndl DW jolnc

NA 1 2 3 4 NAl2 34

NA 1 2: 3 4 NAI 2 3 4

NA I 2 3 ..

5. Physiolopeal tremor noted at rest:

NA I 23"

NA I 2] 4 NAI 2] 4

NA I 2 J 4 NA l 2 ) ..

NA 12 J 4 NA 12] 4

6. IntenSlOfllremor DOled with purposeful movements fuquerM:y N A 1 2 34 Seventy NA I 2 3 ..

NA) 2 34 NA I 23"

NA I 2 , 4 SA J 2 ] 4

NA 12 3 4 NAI 2 ] 4

1. End range movements (hyperextension) ftOlCld when finger pmses down NA I 2 3 4 NA 1 2 3" L 1Pjoi.nu byperextend NA 1 2 ].. NA 1 2 ) 4 b. MP joiQu ex~ssivelye xteDd

NA 1 2 J 4 NA I 2 34

NA I 2 3 4 NA I 1 ) 4

NA I 234

""""""" Severity

8. bIVal ved tinters have uncontroltabl.e tnO~u v.rhen Ml.jacent tillogtr depreued on surface

a. UncontroUably flex ~r.cy

Severity b . UncOncroilablyelltend frequcllCY

Severity 9. Lack.of voluoUry control on tasks ortlter thantatg ettask (self report) (126)

NA.1 2 34 NAI234

NA 1 2 ] 4 NA t 2 3 4

NA J 2 3 4 NAI 2l4

N"A l 2 34 NAI 2 34

NA t 2: 3 4 NA 12 ) 4

NA 12 3 .. NA 1 2 34

NA I 2 3 4 NA 123 4

NAI 2] 4 NA 1 2 3 4

NA 123 4

NA I 2 3 4

NA 1 2 3 4

T0 1at Rl ah t _ %

1 Wriling movementsilowerthan normal NA I :2 34

NA 1 2 3 4

_

NA 1 2 3 4

T I.Jt.J Left _ %

T nb) Rlg bt _ _Tot al Lt rt _ 'lb

%

Comments

711199

NA I 2 3 4 NA1 2 ) 4

NA 1 2 ] 4 NA12 34

NA 1 2 ]4 NAI l 34

NA I l l4 NA I2 l4

Nil. I 2 3 4 NA 12)4

NA t 2 3 4 NA1 2) 4

October-December 2000 301