ABSTRACT: The purpose of this study was to identify hand factors that change over a five-year period that may be risk factors for the development of functional disability in persons with systemic sclerosis (scleroderma). Sixty individuals with scleroderma were administered assessments of grip and pinch strength, joint range of motion, and pain, and were observed for the presence of digital ulcers, digital scars, calcium deposits, puffy fingers, and tendon friction rubs. Matched-pairs chi square analyses and Fisher’s exact tests were performed to compare variables at year 1 and five years later. Grip and pinch strength increased as did joint motion except for the wrist and thumb carpometacarpal joint. There were also significant increases in the presence of scars, friction rubs, calcium deposits, and puffy fingers. Regression analysis was done to determine which variables predicted functional ability. Only puffy fingers predicted functional disability. In conclusion, hand impairment persisted over time while functional ability decreased.
J HAND THER. 2004;17:407-411.
Systemic sclerosis or scleroderma is a multisystem disease with two major subtypes: diffuse and limited cutaneous scleroderma. In diffuse scleroderma, the classic form of the disease, there is symmetrical and generalized (diffuse) involvement of skin affecting the trunk face, proximal and distal extremities, and visceral involvement that develops relatively early.1 In the limited cutaneous variant, skin thickening is generally restricted to the face and hands, and visceral manifestations may not be present for a prolonged period.1
The hands in individuals with both subtypes of scleroderma show skin thickening, tendon friction rubs (tendon sheath inflammation in the flexor and extensor tendons), digital pitting scars on the fingertips, digital ulcers, puffy or swollen fingers, Raynaud’s phenomenon, and subcutaneous calcium buildup.1-4 Palmer et al.3 described the hands in individuals with scleroderma as showing characteristic “claw” deformities, a loss of flexion at the metacarpophalangeal joins, and a loss of extension at the proximal interphalangeal joints. However, they did not follow individuals over a time period to determine whether the finger deformities increased or decreased during the course of the disease or led to functional disability.
The long-term ability to perform activities of daily living is of interest to hand therapists who play a role in preventing deformities and preserving hand function in persons with scleroderma.5,6 Poole and Steen7 measured a number of factors observed clinically to be associated with the ability to perform daily tasks. The presence of puffy fingers, joint pain and swelling, and measures of grip strength, thumb palmar abduction, wrist extension, and composite index and middle finger motion all correlated with the ability to dress, eat, brush teeth, reach, and grasp. Poole8 also reported that grip strength, thumb palmar abduction, wrist extension, digital sores, calcium deposits, and tendon friction rubs correlated with the ability to hold four common objects ( glass, saucepan handle, key, coin). Thus, it appears that hand involvement in individuals with scleroderma is associated with overall functional ability. Due to the progressive nature of scleroderma, it may be instructive to examine hand involvement at different points irv time. Although prognosis in systemic sclerosis is largely dependent on the degree of visceral involvement, Medsger9 reported that hand dysfunction was also related to morbidity. He estimated that hand impairment increased in the first five years after diagnosis and then plateaus in diffuse scleroderma. In the limited cutaneous subset, hand dysfunction continues to increase throughout the course of the disease. The purpose of this study was to identify the hand factors that change over a five-year time period that may be risk factors for the development of functional disability in persons with both types of scleroderma.
METHODS
This was a prospective or cohort study where participants were tested at two points in time, five years apart.
Participants
Participants for this study consisted of 60 individuals who fulfilled American College of Rheumatology criteria for scleroderma.10 Information on age, sex, educational level, and occupation was collected at the beginning of the study. At the beginning of the study, 16 participants were classified as having limited cutaneous scleroderma, 39 as diffuse, and five as unclassified. Five years later, 15 cases were classified as limited, 40 as diffuse, and five unclassified.
There were 52 women and eight men. The ages of the participants ranged from 19 to 86 years at completion of the study with a mean of 51.06 and a median of 52.5 years. Disease duration ranged from five to 47 years with a mean of 14.4 and a median of 12.5 years. It was found that 1.7% (1/60) had not completed high school, 60% (36/60) had completed high school, 30% (18/60) had some education beyond high school such as college, and 8.3% (5/60) had an unknown education level. At the beginning of the study, participants reported their occupations were as follows: 20% (12/60) were clerical workers, 18.3% (11/60) were private household workers or service workers, 18.3% (11/60) were housewives, 8.3% (5/60) were professional or technical workers (e.g., nurses, teachers, technicians), 6.6% (4/60) were sales workers, 6.6% (4/60) were operative and kindred workers (e.g., dress makers, bus drivers, taxi drivers); 5% (3/ 60) were managers, officials, or proprietors; and 5% (3/60) were craftsmen or foremen. The occupations of seven cases were unknown.
Procedures
The plausible risk factors selected for this study represent factors that correlated with disability.7,8 Additional factors represent a spectrum of clinically important items that may be related to hand involvement, such as educational level and occupation. We did not control for medications because information was not available for all participants. Participants were evaluated at the beginning of the study ( year 1, time 1) and were reevaluated five years later (time 2).
Physical Examination
The presence or absence of the following factors was recorded: digital ulcers, digital scars, calcium deposits, puffy fingers, and tendon friction rubs. Grip strength was measured with a vigorimeter, a rubber bulb attached to a meter. Pinch strength was measured with a pinchmeter. For both grip and pinch strength, three consecutive measurements were taken, alternating the right hand with the left hand. The average of the three measurements for each hand was recorded. Pain was assessed with the pain visual analogue scale on the Health Assessment Questionnaire.10 Active range of motion (ROM) for each joint in the hand and wrist was measured with a goniometer and served as determination of deformity. Based on these ROM measurements, five deformity measures were calculated: the number of extension contractures (flexion less than or equal to 45 degrees) at the metacarpophalangeal (MCP) joints, the number of flexion contractures ( finger flexed 45 degrees or greater) at the proximal interphalangeal (PIP) joints, the distance in centimeters from the fingertip to distal palmar crease for each finger (FTOP), thumb palmar abduction in degrees of motion, and number of amputations.
Severity of skin thickness was used as measure of disease severity. Skin thickness of the hand and fingers was rated according to the scale of described by Clements et al.” With this scale, the skin on the dorsal surface of the fingers and hand is pinched. The ability to make a skinfold is rated from O (uninvolved) to 3 (severe skin thickening). Disease subtypes, diffuse or limited cutaneous scleroderma, were also recorded.
The outcome measure for this study, functional disability, was measured by the Health Assessment Questionnaire Disability Index (HAQ). The disability index of the HAQ was designed to measure functional ability in rheumatic disease patients.10 The HAQ consists of eight components of daily living (dressing and grooming, arising, eating, walking, hygiene, reach, grip, and outside activity). Questions in each component are scored on a four-point scale, from “without difficulty” to “unable to do.” A disability index was calculated by summing the highest score in each component and dividing by the number of components answered. The mean disability index for individuals with systemic sclerosis was determined to be 0.92.7 Concurrent validity of the HAQ in scleroderma was established by comparing an individual’s self-report responses with actual performance of selected items on the HAQ.12 Support for construct validity was provided by Poole and Steen7 because the HAQ differentiated individuals with the diffuse and limited cutaneous subtypes of the disease.
Data Analysis
Variables were described using means, medians, and frequency distribution. Additionally, cross-tabulations were calculated matching independent variables with improvement from time 1 (year 1) to time 2 (five years later). Categorical variables were scars, ulcers, friction rubs, calcium, Raynaud’s phenomenon, and puffy fingers. Continuous variables were grip strength, lateral pinch, palmar pinch, wrist extension, thumb abduction, measures of each fingertip to the palmar crease \(FTOP 2-5), and thumb flexion. Matched-pairs chi square analysis ( for categorical variables) as well as Fisher’s exact tests and paired t-tests (for continuous variables) were performed to compare variables at time 1 and time 2. Regression analysis was performed to determine which variables predicted changes in HAQ scores. Multiple logical regressions were used to predict improvement over time by the significant risk factors determined from the univariate analysis.
RESULTS
Table 1 demonstrates the results of comparisons from time 1 and time 2 for all risk factors broken down by continuous variables. Grip and pinch strength increased. In general, joint motion of the fingers increased while CMC and wrist motion decreased. However, the only continuous variables showing significant change were lateral pinch, and palmar pinch. Table 2 shows the results of comparisons from time one to time two for the categorical variables. The percentages of all these variables increased in the five year period. However, the categorical variables showing significant changes were the presence of scars, tendon friction rubs, calcium deposits, and puffy fingers. The mean HAQ score was 0.73 at time 1 and 0.81 at time 2. Thus, disability increased, but not significantly.
The continuous and categorical variables that significantly changed over time were entered into the regression analysis. The regression analysis revealed that only puffy fingers predicted change in total HAQ disability scores.
DISCUSSION
In general, joint motion and strength were relatively unchanged over the five-year period. Interestingly, pinch strength increased significantly. Palmer pinch, where the thumb opposes the pads of the index and middle fingers, has been reported to be the most commonly used pinch for both picking up and using small objects. 3’14 Lateral pinch is the second most commonly used pinch pattern. It has been reported that 2.5 Ib of pinch is all that is needed to perform 90% of tasks of daily living.15 The increase in pinch strength might reflect a decrease in disease activity, which might explain why functional disability did not decrease. However, the presence of the variables related to the disease itself increased. These findings are different from those reported by Medsger and Steen,16 who reported a significant increase for calcium deposits but a decrease in puffy fingers and tendon friction rubs. The smaller sample size in our study may account for this difference in results. Although grip strength, joint motion, calcium deposits, and ulcers correlate with functional ability,7,8 in this study, only puffy fingers predicted disability. Several explanations are possible. First, participants in this study, as compared with published data on other persons with scleroderma, had minimal disability/'” In addition, the participants had minimal joint involvement and skin thickness. Although there were no significant differences in the variables for diffuse and limited participants, findings might be very different if the sample had been more severely involved and disabled. A second reason that other variables did not predict disability may be that the outcome measure, the HAQ, was not sensitive to changes in hand function. Silman et al.17 suggest that the HAQ includes areas that are not considered major problems in scleroderma. Using a different outcome measure that emphasizes hand function, such as the Scleroderma Functional Ability Questionnaire17 or the Hand Function Disability Scale,18,19 might yield different results. Third, although hand function was of particular interest to us, scleroderma involves other parts of the body as well, including the internal organs. The combination of impairments from many bodily systems may predict disability beyond hand function. Altman et al20 showed that proximal muscle weakness, joint swelling, and deformity early in the course of the disease were related to decreased survival.
TABLE 1. Mean Values for Continuous Variables for Time 1 and Time 2
TABLE 2. Percent Response for Categorical Variables for Time 1 and Time 2
Most studies examining disability in scleroderma have examined the presence of clinical disease variables. Only two studies did performance-based evaluations of hand function.7,8 However, whereas those studies only assessed hand function at one point in time, they did find that hand function was related to disability. The present study was the first to examine changes in performance outcomes in the hand over time. Although in our study the participants had minimal hand contractures, contractures occur frequently in the hand.21 Our criteria for a contracture may have been too severe. We identified a PIP contracture as flexed to 45 degrees or greater and an MCP contracture as less than 45 degrees of flexion. if we had used less strict criteria or used total joint motion, our results might have been different.
The participants in our study did not report receiving occupational or physical therapy during the five years of this study. However, the participants did receive therapy when their condition was first diagnosed. They also received care at a major medical center from physicians specializing in scleroderma. Thus, the most up-to-date treatment may have contributed to the reason why hand variables did not decrease significantly.
Clearly, persons with scleroderma have significant hand involvement.16,21 Yearly assessments with newly diagnosed cases could identify sequential stages of disease progression to determine optimal time for therapeutic intervention such as occupational or physical therapy. Further studies using larger sample sizes and outcomes specific to hand function should also be preformed.
Acknowledgments
The authors acknowledge the assistance of Timothy Sypolt, Camen Scolieri, Mary Lucas, and Carol Brewer, MS, OTR/ L, in collecting data; Aysa Alseayleck and Beena Suri foiassistance with data input and analysis; and Thomas A. Medsger, Jr., MD, and Virginia Steen, MD, for providing continued support. Supported in part by the University of Pittsburgh Research Development Fund and the Western Pennsylvania Chapter of the Arthritis Foundation. Portions of this manuscript were presented at the Annual Conference of the Association of Rheumatology Health Professionals, Orlando, Florida, October 1996.
REFERENCES
1. Masi AT, Rod nan GP, Mcdsger TA Jr, et al. Preliminary criteria for the classification of systemic sclerosis (scleroderma). Arthritis Rheum. 1980;23:581-90.
2. Entin MA, Wilkinson RD. Scleroderma hand : a reappraisal. Orthop Clin North Am. 1973;4:1031-8.
3. Palmer DG, Hale GM, Grennan DM, Pollock M. Bowed fingers: a helpful sign in the early diagnosis of systemic sclerosis. J Rheumatol. 1981;8:266-72.
4. Steen V, Contc C, Medsger TA Jr. Twenty-year incidence survey of systemic sclerosis (scleroderma). Arthritis Rheum. 1988;31:S57.
5. Melvin JL (1996). Scleroderma (systemic sclerosis): Treatment of the hand. In Hunter JM, Mackin EJ, Callahan AU (eds). Rehabilitation of the Hand: Surgery and Therapy. St. Louis, MO: Mosby, 1996, pp 1385-97.
6. Poole JL. Occupational and physical therapy. In: Clements PJ, Purst DE (eds). Systemic Sclerosis. Baltimore, MD: Williams 6 Wilkins, 1995, pp 581-90.
7. Poole J, Steen V. The use of the health assessment questionnaire (HAQ) to determine physical disability in systemic sclerosis. Arthritis Care Res. 1991;4:27-31.
8. Poole JL. A description of grasp pattern variations seen in scleroderma. Am J Occup Ther. 1994;48:46-54.
9. Medsger TA Jr. Systemic sclerosis (scleroderma). In: Fries JF, Ehrlich GE (eds). Prognosis: Contemporary Outcomes of Disease. Bowie, MD: Charles Press Publishers, 1982, pp 378-80.
10. Fries JF, Spitz PV, Kraines RG, Holman HR. Measurement of patient outcome in arthritis. Arthritis Rheum. 1980;23:137-25.
11. Clements PJ, Lachcnbruch PA, Seibold JR, Tee B, Steen V, Brennan P. Skin thickness score in systemic sclerosis: an assessment of interobserver variability in 3 independent studies. J Rheumatol. 1993;20:1892-6.
12. Poole J, Williams C, Bloch D, Hollak B, Spitz P. Concurrent validity of the health assessment questionnaire disability index in scleroderma. Arthritis Care Res. 1995;8:189-93.
13. Harty M. The hand of man. Phys Ther. 1974;51:777-9.
14. Taylor CL, Schwarz RJ. The anatomy and mechanics of the human hand. Artif Limbs. 1955;3:22.
15. Swanson AB. Evaluation of impairment of hand function. In Hunter JM, Mackin EJ, Callahan AD (eds). Rehabilitation of the Hand: Surgery and Therapy. St. Louis, MO: Mosby, 1996, pp 115-25.
16. Medsger TA Jr, Steen V. Classification, prognosis. In: Clements PJ, Furst DE (eds). Systemic Sclerosis. Baltimore, MD: Williams & Wilkins, 1995, pp 51-64.
17. Silman A, Akesson A, Newman J, et al. Assessment of functional ability in patients with scleroderma: a proposed new disability assessment instrument. J Rheumatol. 1998;25:79-83.
18. Duruz MT, Poiraudeau S, Fermanian J, et al. Development and validation of a rheumatoid hand functional disability scale that assesses functional handicap. J Rheumatol. 1996;23:1167-72.
19. Brower LM, Poole JL. Reliability and validity of the Duruz Hand Index in persons with systemic sclerosis (scleroderma). Arthritis Care Res. (In press).
20. Altman RD, Medsger TA, Bloch DA, Michel BA. Predictors of survival in systemic sclerosis (scleroderma). Arthritis Rheum. 1991;34:403-13.
21. Melone CP, McLoughlin JC, Beldner S. Surgical management of the hand in scleroderma. Cur Opin Rheumatol. 1999;11:514-20.
Janet L. Poole, PhD, OTR/L
Departments of Orthopaedics and Rehabilitation
Occupational Therapy Graduate Program
University of New Mexico
Albuquerque, New Mexico
Valerie J.M. Watzlaf, PhD, FAHIMA, RHIA
Department of Health Information Management
School of Health and Rehabilitation Sciences
University of Pittsburgh
Pittsburgh, Pennsylvania
Frank D’Amico, PhD
Department of Mathematics and Computer Science
Duquesne University
Pittsbu\rgh, Pennsylvania
Correspondence and reprint requests to Janet L. Poole, PhD, OTR/ L, Occupational Therapy Graduate Program, Department of Orthopaedics and Rehabilitation University of New Mexico, MSC 09 5240, Albuquerque, NM 87131-0001; e-mail:
Copyright Hanley & Belfus, Inc. Oct-Dec 2004
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