Studies

RELIEF OF CARPAL TUNNEL SYNDROME WITH PERSISTENT PASSIVE STRETCHING OF THE FLEXORS AND EXTENSORS OF THE HAND AND FINGERS, A CLINICAL STUDY

William J. Ruch, D.C., Life Chiropractic College-West Hayward, CA

Linda Rogers, PhD, University of California, Berkeley

Independent Review Consulting, Inc. P.O. Box 170, San Anselmo, Ca 94979-0170

STUDY ACKNOWLEDGMENTS

The staff of NOCC, the participants of the study.

RELIEF OF CARPAL TUNNEL SYNDROME WITH PERSISTENT PASSIVE STRETCHING OF THE FLEXORS AND EXTENSORS OF THE HAND AND FINGERS, A CLINICAL

ABSTRACT

STUDY DESIGN

Patients with Carpal Tunnel Syndrome (CTS) or Repetitive Stress Injury (RSI) were recruited for a longitudinal study involving a “wrist releif glove”, designed to elongate or stretch the flexors and extensors of the hand and fingers.

OBJECTIVES

The objective was to evaluate patient outcomes before and after treatment with the glove. A standardized questionnaire was used before and after a three-month period as a measure of outcome.

BACKGROUND

In the practice of chiropractic for CTS and RSI it was observed that passive stretching of the tissues from the elbow to the wrist gave relief. So a device was developed that could be used at home on a frequent basis to change the length of these muscles and tendons.

METHODS AND MEASURES

The Relief Glove was given to volunteers for daily use of at least 20 minutes per hand. Subjective measures were used to assess symptoms and functional status. A validated 11 item “symptom severity scale” that includes questions regarding daytime pain, nocturnal pain, tingling, numbness and weakness was used for symptom assessment. Responses were based on a 5-point Likert scale for pre treatment symptoms as well as post treatment status. “Functional status” was measured for 8 items on a 6-point scale.

RESULTS

78 participants took the glove, of those 33 were compliant with daily or near daily use. 27 were completely satisfied or very satisfied, relieved of all or most of their symptoms.

CONCLUSIONS

The use of the Relief Glove for the persistent passive stretching of the flexors and extensors of the hand and fingers is effective for the treatment of CTS and RSI.
Key words: Repetitive Stress Injury, chiropractic

INTRODUCTION

The occurrence of wrist pain in various forms is a common and costly occupational problem affecting thousands of people every year. Repetitive stress injuries (RSI) to the hand and wrist have six common forms; carpal tunnel syndrome (CTS) is the most prevalent (Sheon, RP, et al., 1998). The common feature of many wrist complaints is loss of joint space of the carpus (Chernin, ’84, Stahelin, ’89). Various investigators describe stenosis (Dekel, ’80) and compression (Phalen, ’51). What could cause the normal relations of the bones, tendons and nerves to alter sufficiently to result in these terribly painful and debilitating changes? The question posed by this clinical study is: does tightening and shortening of the flexor and extensor muscles of the hand and wrist play a role in these afflictions?

In the practice of chiropractic treatment of these complaints it was noticed that a common feature of the injured patients was forearm and elbow pain and tenderness. The insertion of the flexor digitorum profundus, palmaris longus, pronator teres, and others on the anterior surface of the elbow would be painful to palpation. The insertions of the extensor groups digitorum, digiti minimi, carpi ulnaris and, carpi radialis among others, would all be distressed and painful on evaluation. This indicates that thickening and shortening of these tissues could be part of the syndrome. It has been shown that these tendons increase in mass with exercise, i.e. stress (Woo, SL,’82). Certainly this condition could cause carpal collapse and loss of joint space in the hand and fingers as well. Also thickening of the tendons through the wrist region causing stenosis could be a consequence of contraction of the flexor-extensor groups (Woo, S.L., 1982). Deformations of tendons and ligaments have two main components: time and weight. Persistent passive stretch to reform ligaments and re-hydrate discs is used in spinal rehabilitation (Garde,’98, Miller “87). Can a similar approach be used on the forearm muscular and tendoninous structures of the hand and fingers? Studies done on intervertebral discs and spinal ligaments indicate that to overcome the natural elastic deformation of these tissues, a constant stretching force for 12 -15 minutes must be achieved. The actual increase in length of these tissues occurs after the natural flexibility of the tissues has been reached (Woo, ’82), and this is the actual lengthening part of the treatment. The steepest part of the change curve (length graphed against time) is 20 to 25 minutes after the beginning the session, and there is little change after that.

Pilot experiments were done to determine the amount of weight that was necessary to provide elongation of the forearm muscles without harm. Approximately one pound of weight was found to work for a small hand, one and a half pounds for a medium size hand and two pounds for a large hand. If there was too much weight on the hand, the subject could not tolerate a 15-minute session, thus it was easy to gauge the correct weight.

METHODS

Volunteers were recruited that had one or more of the following symptoms: numbness and tingling in the hand, night pain in the hand, daytime hand pain made worse with activity, constant hand pain, and thumb and hand weakness that affects grip and dexterity. Subjects were required to read and sign a consent form approved by Independent Review Consulting, Inc. Two orthopedic tests were performed: Finkelstein, Phalen, Tinel, and a strength test. A pre-treatment questionnaire was administered. The questionnaire had symptom assessment and functional status sections. The validated 11-item symptom assessment had a 5-point Likert scale for responses, e.g. none, mild, moderate, severe and very severe. The validated 8-item scale on functional status used a 6-point response scale, e.g. no difficulty, mild, moderate, severe, very severe difficulty and can’t perform.

The instructions on the use of the Relief Glove were as follows: The glove is to be used in a relaxed, passive manner, with adequate support of the elbow and forearm and hand. If the subject is sitting, the fingers and weight should dangle over the edge of the arm of a chair, or if on the thigh the fingers and weight should hang over the edge of the knee. If resting in a recumbent position, the forearm and hand rest across the abdomen, and the fingers and weight hang over the opposite side of the body. The hand can alternate between palm up and palm down, though only palm down works for the recumbent position. A daily session of 20 minutes but not more than 40 minutes is recommended for each hand for 3 months. A daily log in the form of pre-addressed and stamped post cards was given to the volunteers. This allowed us to verify compliance and group the volunteers into compliant, partly compliant and not compliant groups. The participants were contacted and asked to return for reevaluation. Most did not return for the reevaluation, but were contacted and surveyed by phone. As part of the follow-up, each was asked for their overall result on 5-point scales from completely satisfied to very dissatisfied.

There were 11 questions for self-assessment of symptom severity:

1. How severe is the hand or wrist pain that you have right now?
2. How often did hand or wrist pain wake you up during a typical night in the past 2 weeks?
3. Do you typically have pain in your hand or wrist during the daytime?
4. How often do you have hand or wrist pain during the daytime?
5. How long, on average, does an episode of pain last during the daytime?
6. Do you have numbness (loss of sensation) in your hand?
7. Do you have weakness in your hand or wrist?
8. Do you have tingling sensations in your hand?
9. How severe is the numbness (loss of sensation) at night?
10. How often did hand numbness or tingling wake you up during a typical night during the past 2 weeks?
11. Do you have difficulty with grasping and use of small objects, such as keys or pens?

The responses were a 5-point scale with 1 for no or none and 5 for very severe or constant.

Functional status was evaluated with the 8 following activities: writing, buttoning, holding a book while reading, gripping a telephone receiver, opening jars, household chores, carrying grocery bags, bathing and dressing. The rating went from 1 for no difficulty to 6 for unable to perform.

There were 78 original participants and only 33 (42%) followed the instructions and completed the follow up survey and evaluation. There were also 11 compliant users and 11 intermittent users who initially did not respond with the request for a follow-up contact, but who later responded to our phone calls.

RESULTS

There were 78 volunteers who were evaluated and given a glove. Of those 23 did not respond or provide evidence that they used the glove, 22 used the glove regularly to intermittently but did not get reevaluated and 33 (42%) people kept daily use logs and were compliant with use of the glove and follow up evaluation. Their responses to the overall satisfaction question, Figure 1, indicated that 16 of the participants were completely relieved of their symptoms and 11 were almost relieved of all their symptoms. That is an 82% dramatic improvement with use of the glove as recommended.

Figure 2 shows the number of responses for each level of the scale, averaged over the 11 symptom severity questions, with error bars indicating one standard deviation. A response of ’5′ indicates the most severe pain, with ’1′ indicating no pain. The follow-up responses (dark bars) indicated less pain than the baseline. For example, the average number of ‘no pain, or 1’ responses was 19.0 ± 4.8 for the follow-up, which much higher than the baseline (average of 10.6 ± 5.5). On the other hand, for the severity level of 3, there was an average of 3.2 ± 2.0 responses for the follow-up and 9.4 ± 3.5 for baseline. In order to evaluate the statistical significance of the result, an overall scale was first calculated as the sum of the follow-up or baseline responses for all of the questions for each subject. A low score on this scale thus indicates low severity. Then, for each subject, the follow-up scales were subtracted from the baseline scales. These difference scores were positive (indicating a good outcome) for 27 of the 32 patients (one subject was dropped for incomplete responses), 0 for three, and negative for 2. The average of the difference scores was 7.2 ± 8.1, which is expected to be zero for an outcome of no overall change. A paired t-test, indicates that this difference is significant, p < 0.001.

Figure 3 presents the Functional Status question results in the same format as the Symptom Severity results in Figure 2. These results are slightly less dramatic, but the indication of improvement was still clear. In this case, the average number of good functional status responses (1) was 21.9 ± 3.9 for the follow-up, and the corresponding baseline average was 14.6 ± 5.0. For the response level of 3, the average for the follow-up was 3.4 ± 1.8 responses, and 7.4 ± 3.2 for baseline. The average of the difference scores was 3.2 ± 4.7, which is significant at a level of p < 0.003. Of 31 subjects with complete responses, 3 difference scores were negative, 6 zero, 22 positive.

DISCUSSION

The results indicate a clear improvement for those compliant with the treatment program. They have an inherent bias in that patients with the motivation to use and report their results are more likely to have a good response, but the fact of improvement is not in dispute.

The concept of passive persistent stretch as a means of increasing carpal space and relieving RSI is not in the literature. Pain in the elbow and forearm is a common associated symptom with RSI but is not mentioned in most references. The flexors and extensors of the hand and wrist originate in the elbow region and the tightening and shortening of these muscles with activity is a reasonable expectation. Compression of the carpal region results from this tightening, and can be the source of pain and other symptoms in some of those diagnosed with RSI. A home device that can be used daily for relief of these types of symptoms would be desirable for many reasons. Cost of the Wrist Release glove is about $60. The treatment time is 12 weeks or less, and then those patients with a positive response tend to use it intermittently when they re-injure themselves with excessive use. Thus, it can be used more often, with less cost, than frequent physical therapy or chiropractic office visits would require.

As with most clinical studies and procedures requiring long-term use of a device, compliance was a problem. That will be the problem for most people who would receive this device. This is one of the major problems with any fitness or rehabilitation program. Also, we could do a better job of educating the participants of the concept of stretch and increasing the carpal compartment.

CONCLUSION

The symptoms of RSI are complex and varied. The collapse of the carpal space is one feature. It is suggested that the shortening and thickening of the tendons crossing the carpal space plays a role. This small study indicates that stretching of these tendons contributes to symptom relief. This strongly suggests that further study of elongation techniques of the wrist and hand muscles and tendons should be done.

REFERENCES

Garde RE, Payne M, Cervical Traction; A Review. In: Harrison HH, ed. Spinal Biomechanics: A Chiropractic Perspective, American Journal of Clinical Chiropractic:
1998:443-481.

Stahelin A, Pfeiffer K, Sennwald G, Segmuller G, Determining Carpal Collapse, An Improved Method, The Journal of Bone and Joint Surgery, Oct. 1998: 71-A: 9,1400-1405.

Miller LS, Cotler HB, De Lucia FA, Cotler J M, Hume E L, Biomechanical Analysis of Cervical Distraction. Spine, 1987: Vol. 12;9: 831-837

Chernin MM, Pitt MJ, Radiographic Disease Patterns at the Carpus. Clinical Orthopeadics and Related Research, July/August 1984;187: 72-80

Youm Y, McMurty RY, Flatt AE, Gillespie TE, Kinematics of the Wrist, 1. An Experimental Study of Radial-Ulnar Deviation and Flexion-Extension. The Journal of Bone and Joint Surgery. June 1978, Vol. 60-A;4:423-431

McMurty RY, Youm Y, Platt AE, Gillespie TE, Kinematics of the Wrist, II. Clinical Applications. The Journal of Bone and Joint Surgery. Oct.1978, Vol. 60-A;7:955-961

Dekel S, Papaioannou T, Rushworth G, Coates R, Idiopathic carpal tunnel syndrome caused by carpal stenosis. British Medical Journal. May, 1980, 31:1297-1299
Viidik A, A Rheological Model for Uncalcified Parallel-Fibred Collagenous Tissue. Journal of Biomechanics. 1968, 1:3-11

Phalen GS, Spontaneous Compression of the Median Nerve at the Wrist. J.A.M.A., April 14, 1951: 1128-1133.

WooSL, GomezMA, WooYK, AkesonWH, MechanicalpropertiesoftendonsandligamentsII. Biorheology. 1982, 19(3): 397-408


FIGURE 1:

The responses to the overall satisfaction question indicated that 16 of the participants were completely relieved of their symptoms and 11 were almost relieved of all their symptoms. That is an 82% dramatic improvement with use of the glove as recommended.


FIGURE 2:

Number of responses in each level of the Symptom Severity scale, averaged over 11 questions. Severity was shown to have decreased at follow-up by the increased number of low severity responses questions compared to the baseline.


FIGURE 3:

Number of responses in each level of the Functional Status scale, averaged over 8 questions. Function was shown have improved by the increased number of low responses for the follow-up questions compared to the baseline.