CRITICALLY APPRAISED PAPER (CAP) Horng, Y. S., Hsieh, S. F., Tu, Y. K., Lin, M. C., Horng, Y. S., & Wang, J. D. (2011). The comparative effectiveness of tendon and nerve gliding exercises in patients with carpal tunnel syndrome: A randomized trial. American Journal of Physical Medicine & Rehabilitation, 90, 435 442. http://dx.doi.org/10.1097/phm.0b013e318214eaaf CLINICAL BOTTOM LINE: This study compared the use of tendon gliding and nerve gliding in conjunction with conservative treatment of splinting and paraffin bath therapy for mild to moderate carpal tunnel syndrome (CTS). The researchers found that all three groups (control, tendon gliding, and nerve gliding) showed significant improvement on the Boston CTS Questionnaire Symptom Severity scale and Visual Analogue Pain scale. The group performing tendon gliding also showed significant improvement on the Functional Status scale of the Boston CTS Questionnaire; the Disabilities of the Arm, Shoulder, and Hand (DASH) Questionnaire; and the Physical domain of the World Health Organization Quality of Life Brief Questionnaire. Splinting has been consistently shown to be effective in conservative management of mild to moderate CTS. Tendon gliding and nerve gliding exercises are also a common intervention in conservative management of CTS, even though their efficacy was controversial in previous research that studied them together. This study indicates that tendon gliding may be more beneficial than nerve gliding exercises in conservative management of CTS, but more research with a larger sample size is needed before any gliding exercises should be considered best practice for this population. RESEARCH OBJECTIVE(S) List study objectives. Investigate the individual effectiveness of tendon gliding and nerve gliding exercises when combined with conventional treatment for CTS of splinting and paraffin therapy DESIGN TYPE AND LEVEL OF EVIDENCE: Level I: Prospective, randomized, single-blind study SAMPLE SELECTION How were subjects recruited and selected to participate? Please describe. 1
Sixty consecutive patients with CTS were recruited from the rehabilitation department of a community hospital from 2007 to 2009. Inclusion Criteria Participants needed to have subjective symptoms, including pain and numbness along the median nerve distribution and nocturnal pain; a positive Tinel s sign or Phalen s sign; and electrophysiological evidence of CTS. Exclusion Criteria Participants were excluded if they were younger than 18 years old; had another medical disorder, including diabetes mellitus, renal failure, autoimmune disease, or hypothyroidism; were pregnant; or had had previous wrist trauma or surgery. SAMPLE CHARACTERISTICS N= (Number of participants taking part in the study) N = 53 #/ (%) Male 3 (5.66%) #/ (%) Female 50 (94.3%) Ethnicity Not reported Disease/disability diagnosis All participants had either unial or bial CTS with a distal motor latency greater than 4.4 ms or a distal sensory latency greater than 3.4 ms. INTERVENTION(S) AND CONTROL GROUPS Add groups if necessary Group 1: Tendon gliding Brief description of the intervention How many participants in the group? Where did the intervention take place? Who delivered? Participants were instructed to wear a custom-made neutral volar orthosis at night and attend paraffin therapy sessions at the treatment facility. They were also taught how to perform tendon gliding exercises as well as given written instructions. Twenty participants were randomly assigned; 18 completed the study and were analyzed. One was lost to follow-up, and one discontinued intervention because of the time commitment. Instruction and paraffin therapy were completed at the Department of Physical Medicine and Rehabilitation connected with a community hospital. Orthosis and tendon gliding interventions were carried out at home. A therapist not involved in evaluating outcomes administered the interventions. 2
How often? For how long? Group 2: Nerve gliding Brief description of the intervention How many participants in the group? Where did the intervention take place? Who delivered? How often? For how long? Group 3: Control Brief description of the intervention How many participants in the group? Where did the intervention take place? Who Delivered? How often? Instruction included wearing the orthosis at night and attending paraffin therapy twice weekly. Participants were to complete five repetitions of tendon gliding exercises three times every day, holding each position for 7 seconds. The intervention lasted 8 weeks. Participants were instructed to wear a custom-made neutral volar orthosis at night and attend paraffin therapy sessions at the treatment facility. They were also taught how to perform nerve gliding exercises as well as given written instructions. Twenty participants were randomly assigned; 19 completed the study and were analyzed. One discontinued surgery for an unrelated health problem. Instruction and paraffin therapy were completed at the Department of Physical Medicine and Rehabilitation connected with a community hospital. Orthosis and nerve gliding interventions were carried out at home. A therapist not involved in evaluating outcomes administered the interventions. Instruction included wearing the orthosis at night and attending paraffin therapy twice weekly. Participants completed five repetitions of nerve gliding exercises three times every day, holding each position for 7 seconds. The intervention lasted 8 weeks. Participants were instructed to wear a custom-made neutral volar orthosis at night and attend paraffin therapy sessions at the treatment facility. Twenty participants were randomly assigned; 16 completed the study and were analyzed. One participant was lost to follow-up. Three discontinued the intervention: One moved, and 2 could not meet the time commitment. Instruction and paraffin therapy were completed at the Department of Physical Medicine and Rehabilitation connected with a community hospital. Orthosis wear was completed at home. A therapist not involved in evaluating outcomes administered the interventions. Instruction included wearing the orthosis at night and attending paraffin therapy twice weekly. 3
For how long? The intervention lasted 8 weeks. Intervention Biases: Check yes, no, or NR and explain, if needed. Contamination: YES NR There was no discussion of contamination bias. It is unclear whether clinic treatment sessions allowed interactions among the members of different intervention groups. Co-intervention: YES NR There was no discussion of possible cointervention. No home diaries were required, and no information was collected on medications or other possible cointerventions for any groups. Timing: Final assessments occurred after an 8-week treatment period. There was no longer term follow-up to assess continued benefits of interventions. Site: YES NO All paraffin treatments occurred in the clinic, and orthotic wear and gliding exercises were completed at home for all groups. Use of different therapists to provide intervention: The therapist who completed the interventions was not involved in data analysis. MEASURES AND OUTCOMES Complete for each measure relevant to occupational therapy: Measure 1: Dynamometer and pinch gauge Grip and palmar pinch strength 4
Measure 2: Measure 3: Measure 4: Measure 5: Semmes Weinstein monofilament test Sensation of the hand Phalen s test Symptoms along the median nerve distribution Tinel s sign Symptoms along the median nerve distribution Boston CTS Questionnaire Function and symptom severity 5
Measure 6: Measure 7: Measure 8: DASH Questionnaire Function Taiwanese version of the World Health Organization Quality of Life Questionnaire Brief Quality of life (Physical, Social, Environmental, and Psychological domains) Visual Analogue Scale Pain Measurement Biases Were the evaluators blind to treatment status? Check yes, no, or NR, and if no, explain. 6
The outcomes were evaluated by physiatrists who were not aware of the group assignments. Recall or memory bias. Check yes, no, or NR, and if yes, explain. YES NR The Visual Analogue Scale, DASH, Boston CTS Questionnaire, and World Health Organization Quality of Life Measure are all self-report measures and may encourage recall and reports of more positive results, which may favor the interventions. Others (list and explain): Instrument bias might have occurred with grip and pinch measurements. The study occurred over 2 years, and the authors did not report how often calibration was performed on the equipment used. RESULTS List key findings based on study objectives Include statistical significance where appropriate (p < 0.05) Include effect size if reported Analysis of variance showed no significant differences among the three groups. All three groups showed a significant (p <.05) improvement in reports of pain on the Visual Analogue Scale and the Symptoms scale of the Boston CTS Questionnaire. The effect sizes for the two scales were 0.96 and 0.78, respectively, for Group 1; 0.53 and 0.6 for Group 2; and 0.66 and 1.0 for Group 3, where an effect size of 0.2 is considered small, 0.5 is considered moderate, and 0.8 is considered large. Group 1 (tendon gliding) also showed significant improvements (p <.05) on the Boston CTS Questionnaire Functional Status score (effect size = 0.51), the DASH (effect size = 0.51), and the Physical domain of the World Health Organization Quality of Life Questionnaire (effect size = 0.35). After adjustment for baseline data, covariance showed significant differences in the Boston CTS Questionnaire Functional Status scores. A post hoc analysis with Bonferroni correction revealed significant differences in Functional Status scores between Groups 1 and 2. Physical examination scores for the Semmes Weinstein, grip, and pinch tests showed no significant improvements in any of the groups. Was this study adequately powered (large enough to show a difference)? Check yes, no, or NR, and if no, explain. 7
YES NR No priori analysis was completed, so appropriate sample size was not determined, which puts the power of the study into question. This can lead to a Type II error and might affect the significance of the results. Were appropriate analytic methods used? Check yes, no, or NR, and if no, explain. A descriptive analysis was performed, with no significant differences between groups noted. The authors completed a Kruskal Wallis test and a Fisher s exact test to compare baseline data. They used a paired t test and analysis of covariance to compare baseline and follow-up data. The authors also compared pre- and postintervention scores with a mixed-effect model to account for patients with bial CTS and for whether the right or left hand was treated. Groups were compared with covariance, adjusted for baseline data. Post hoc analysis with the Bonferroni correction was performed on the Boston CTS Questionnaire Functional Status scores after initial analysis showed a significant difference. After correction, a significant difference remained between Groups 1 and 2. Were statistics appropriately reported (in written or table format)? Check yes or no, and if no, explain. Statistics were shown in tables and could be easily understood. Was the percent/number of subjects/participants who dropped out of the study reported? Limitations: What are the overall study limitations? The study had several major limitations. Because a priori analysis was not completed, the power and significance of the study are in question. The researchers did not require participants to keep intervention logs, which could have allowed cointervention bias to occur. The lack of log keeping also limits our understanding of what amount of home tendon gliding exercises would be the most beneficial in the clinic setting. Contamination bias could have occurred during the twice-weekly visits to the clinic if sessions of participants from different treatment groups overlapped. An intent-to-treat analysis was not performed, and 7 participants did not complete the study. All dropouts persisted with symptoms at the time of discontinuation. This might have led to an overestimation of the treatment effect. 8
CONCLUSIONS State the authors conclusions related to the research objectives. The addition of tendon gliding exercises to a conservative treatment protocol of splinting and paraffin for clients with mild to moderate CTS may be more beneficial than the addition of nerve gliding exercises. More research is needed to validate these results before it can be determined whether this is the best approach for evidence-based practice. This work is based on the evidence-based literature review completed by Denise D. Allen, MHS OT/L CHT, and MaryJane Mulcahey, PhD, OTR/L, Faculty Advisor, Thomas Jefferson University. CAP Worksheet adapted from Critical Review Form--Quantitative Studies. Copyright 1998, by M. Law, D. Stewart, N. Pollack, L. Letts, J. Bosch, & M. Westmorland, McMaster University. Used with permission. For personal or educational use only. All other uses require permission from AOTA. Contact: www.copyright.com 9