UPPER-EXTREMITY DISORDERS believed to result. The Effects of Splinting on Outcomes for Epicondylitis ORIGINAL ARTICLE

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1 1081 ORIGINAL ARTICLE The Effects of Splinting on Outcomes for Epicondylitis V. Jane Derebery, MD, Jenny N. Devenport, PhD, Geneva M. Giang, MBA, W. Tom Fogarty, MD ABSTRACT. Derebery VJ, Devenport JN, Giang GM, Fogarty WT. The effects of splinting on outcomes for epicondylitis. Arch Phys Med Rehabil 2005;86: Objective: To evaluate the effects of splinting on outcomes for injured workers with epicondylitis. Design: Retrospective cohort study using propensity score methodology to statistically control for all observed pretreatment differences between patients with and without splints. Setting: Nationwide network of 253 occupational medicine clinics. Participants: All injured workers (N 4614) receiving primary care for lateral or medical epicondylitis (International Classification of Diseases, 9th Revision, codes or ). Interventions: Not applicable. Main Outcome Measures: Physician-prescribed rates of duty restrictions and lost time, treatment duration, specialist referrals, and medical and physical therapy (PT) visits and charges. Results: Overall, patients with splints had higher rates of limited duty (P.001), more medical visits and charges (P.001), higher total charges (medical and PT, P.001), and longer treatment durations (P.01) than patients without splints. Evaluating differences for patients who did and did not receive PT, significant differences remained for rates of limited duty (P.05), medical visits (P.01), and medical charges (P.01). Conclusions: Splinting patients with epicondylitis may not optimize outcomes, including rates of limited duty, treatment duration, and medical costs. Key Words: Epicondylitis; Occupational medicine; Rehabilitation; Splints by the American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation UPPER-EXTREMITY DISORDERS believed to result from repetitive and/or forceful work activity are of major concern in occupational medicine and workers compensation. According to the US Bureau of Labor Statistics, between 1988 and 1992 the number of repeated trauma cases reported increased by 144%, compared with a 3% increase for all other injuries and illnesses. 1,2 By 2001, repeated trauma accounted for 4% of the 5.2 million total workplace injuries and illnesses and 65% of occupational illnesses, with work-related upperextremity disorders (WRUEDs) accounting for most of these. 3 Epicondylitis is one of the common WRUED diagnoses. There are conflicting studies on the cause of epicondylitis and, From Concentra Inc, Addison, TX. No commercial party having a direct financial interest in the results of the research supporting this article has or will confer a benefit upon the authors(s) or upon any organization with which the author(s) is/are associated. Reprint requests to Jenny N. Devenport, PhD, Concentra Inc, 5080 Spectrum Dr, Ste 400, West Tower, Addison, TX 75001, Jenny_Novotny@concentra.com /05/ $30.00/0 doi: /j.apmr in particular, its work-relatedness A review of epidemiologic studies of workplace factors by the US National Institute of Occupational Safety and Health (NIOSH) determined that there was insufficient evidence for (1) an association between repetitive work and elbow musculoskeletal disorders and (2) an association between postural factors and epicondylitis. 14 Both findings are contrary to common assumptions of both workers and physicians, which include, for instance, belief in a causal link between keyboarding and epicondylitis. 15 The NIOSH review concluded that there was evidence for an association between forceful work and epicondylitis and strong evidence for a relationship between exposure to a combination of risk factors (force, repetition, posture) and epicondylitis. 14 Most patients with epicondylitis are managed by primary care physicians, and common treatments include rest, ice, nonsteroidal anti-inflammatory drugs (NSAIDs), corticosteroid injections, range of motion exercises, stretching and strengthening exercises, counterforce bracing and splinting, iontophoresis, acupuncture, and ergonomic adjustments or training. Less commonly, refractory cases may be treated surgically The long-term prognosis for epicondylitis is good, with 80% of patients recovering within a year. 19,20 However, there is no strong consistent evidence to support any one treatment as being more efficacious in the long term than any other, including wait and see. 12,18,20-23 Recent research 18,20 suggests that, in the short term (4 6wk), corticosteroid injections may outperform physical therapy (PT), NSAIDs, and wait-and-see treatments, but with longer follow-up, most patients improve regardless of treatment. Study results for splinting, a commonly prescribed treatment, are also equivocal, with some studies yielding findings that conflict with the proposed therapeutic mechanisms of splints. Presumably, splints are offered to patients to provide short-term support to weakened or sore muscles, to reduce pain, and to cushion the injured area thereby promoting return to activity. But in a randomized study 24 of patients with unilateral epicondylitis, none of the bracing conditions (including no brace) was associated with significant differences in pain-free grip strength. In another randomized experimental study of nonimpaired patients, 25 researchers found that wearing a forearm band increased rather than reduced extensor muscle fatigue, as measured by wrist extension force and peak grip isometric force. Such findings suggest that splints might hinder activity and potentially contribute to deconditioning, contrary to indications. Most recently, a randomized clinical trial 26 of brace-only, PT, and combination treatment found mixed results, with different conditions achieving superior results on different outcomes at 6 weeks and no significant differences between groups at 26 and 52 weeks. 26 Despite the paucity of evidence to suggest that relative rest, immobilization, or splinting is indicated in the treatment of epicondylitis, it is common for patients to be restricted from certain activities at work, as well as to be braced or splinted at least initially, to rest the wrist and/or elbow. Such treatment is prescribed even when the job activities are not necessarily forceful or excessive, which raises the concern of overuse or misuse of a medical treatment for a condition that might resolve more quickly without restrictions, rest, or immobilization in many cases. 20 It is quite possible, for example, that once

2 1082 SPLINTING AND EPICONDYLITIS OUTCOMES, Derebery Table 1: Initial Differences Between Treatment Groups, Splint Versus No Splint Variable Splint No Splint Comparisons Mean SD (n 3236) Mean SD (n 1378) Standardized Diff in % % with high severity * Patient age (y) Sex (% male) * Marital status (% married) % with lateral epicondylitis * % treated within 1wk of injury * % initial provider physician % with prior case % with initial drug screen * Region (4: midwest/east, south, west, southeast) 2 3 test * Abbreviation: SD, standard deviation. *P.05. The Fisher exact test used to compare means for all variables except age and region; t test used for age; chi-square used for region. The standardized difference is the mean difference between groups divided by the average standard deviation: 100(m s m ns )/ [(s 2 s s 2 ns )/2], where for each covariate m s and m ns are the subclass means for the splinted and not splinted cases, respectively, and s 2 2 s and s ns are the corresponding variances. Internal rating given by initial treating provider (original scale: no objective findings, mild, moderate, severe; used moderate severe vs mild no objective findings based on frequency analysis, suggesting dichotomous variable more reflective of use). N 3219 and 1376 for splinted and not splinted, respectively, because of missing data. a patient becomes symptomatic of epicondylitis, certain routine activities cause an increase in symptoms, misleading the patient (and doctor) to think that the activity caused the disorder and should be avoided even when use of the arm, despite pain, may in actuality lead to a more rapid recovery. The primary goal of treatment of epicondylitis should be the patient s rapid and enduring return to full functioning. For splinting to be recommended in the context of evidence-based medicine, it would be prudent to show that patients with splints show faster and more sustained improvements in pain and/or function than patients without splints. Specific to occupational medicine and workers compensation, patients with splints would need to have less time off work, less duty restrictions, shorter treatment durations, and lower medical costs than patients without splints. To date, we know of no studies that address each of these work-related outcomes relative to splinting. The purpose of this article was to evaluate the effects of splinting on outcomes for injured workers with epicondylitis. Specifically, retrospective analyses of patients were undertaken to identify pretreatment differences in splinted and nonsplinted patients on background and initial injury characteristics, to statistically control for these differences, and to estimate the effects of splinting on functional and treatment outcomes most relevant to occupational medicine. METHODS Participants The patient population in this study consisted of patients receiving primary care for lateral or medial epicondylitis (International Classification of Diseases, 9th Revision, codes or ) at any clinic within a nationwide network of 253 occupational medical centers. This network, owned and operated by Concentra Inc, sees approximately 7% of US workers compensation patients. Patient records were retrieved from the proprietary internal information management system, which contains patient demographic and injury information, as well as transaction-level treatment, diagnostic, billing, and outcomes information. All patients who were of legal working age (at least 16 years old) and who received primary injury care at the centers with treatment episodes beginning in calendar year 2002 and ending by July 31, 2003, were eligible for the study. Fifty-one patients were excluded because of concurrent treatment for complicating injuries not involving the elbow. A total of 4614 patients remained for inclusion in subsequent analyses. Splinting Splinting was identified from the electronic records for patient visits. A variety of restraints was provided to these patients, at their treating provider s discretion, to reduce movement and apply supportive tension to the elbow/wrist and associated extensor muscles. Because the comparison of interest in this study was splints versus no splints (rather than comparisons of splints applied to the elbow versus both the elbow and wrist), patients were counted as receiving a splint if they received any restraint to the elbow, forearm, or wrist areas including braces, splints, straps, and wrap bandages. Evaluation of Splinting Differences To control for pretreatment differences between patients who did and did not receive splints, the first step was to identify and quantify observed differences. Table 1 presents summary information on available background characteristics and initial condition for patients who did and did not receive splints. Independent t tests and chi-square tests were conducted to assess group differences. No significant differences were observed for patient age (measured in years), the type of initial treating provider (primary care physician [MD or DO] vs physician assistant), patient marital status (single, married), and the existence of any prior injury claim within the network (yes, no). Significant differences were observed for severity ratings by the initial treating provider (patients with moderate to severe ratings were more likely to receive splints than patients with mild ratings), gender (higher rates of splinting for females versus males), diagnosis (higher rates of splinting for patients with lateral versus medial epicondylitis), for treatment lag (higher rates of splinting for patients treated within 1wk of injury vs those treated 1wk), for drug screen (higher rate of splinting for patients who received a drug screen, an optional service provided during the initial visit at the discretion of the employer or governing laws of the area), and for geographic region (patients in the west and southeast regions received

3 SPLINTING AND EPICONDYLITIS OUTCOMES, Derebery 1083 splints more than patients in the south, midwest, and east regions). Statistical Control of Pretreatment Differences In a retrospective study of usual care patterns, it is not reasonable to presume that splinting decisions were made at random, that patients had an equal chance of having a splint versus not having a splint, or that pretreatment differences among patients were uncorrelated with outcome prognoses. In our example, patients with more severely rated injuries were more likely to receive splints, but we might also expect patients with more severe injuries to miss work, to require more duty restrictions, to incur more medical charges, and to have longer treatment durations than less severe cases even before splinting decisions. Thus, an immediate comparison of these outcomes for patients with and without splints would be misleading. Propensity score methodology is a statistical approach used in observational studies to control simultaneously for multiple pretreatment covariates to create equivalent groups of patients who did and did not receive a particular treatment The propensity score represents the conditional probability of receiving a particular treatment in our study, a splint given observed covariates. Simply put, the propensity score reduces the differences between patients on several variables to a one-number summary. If 2 patients, one who received a splint and one who did not, have the same propensity to receive a splint (predicted from a set of potential confounding variables), then they would not systematically differ with respect to the predictor variables. 29,31 That is, these variables would not help predict which of these 2 patients received the splint. As in a randomized experiment, the treatment assignment would be independent of these predictor variables. Thus, observed differences in outcomes for these patients could not be attributed to the pretreatment differences on the predictors because they were balanced at the start. Similarly, if patients are divided into equally sized subclasses based on the magnitude of their propensity scores, it has been shown that the average treatment effect within subclasses (the difference between splinting and not splinting within a given range of propensity scores) will be an unbiased estimate of the true treatment effect ,32 Estimating Propensity Scores and Treatment Effects In our study, the propensity to receive a splint was estimated by using a logistic regression model with splint (yes, no) as the dichotomous dependent variable and the demographic and pretreatment covariates described earlier as predictors. Modeling proceeded iteratively. Once a solution was estimated, the resulting propensity scores (conditional probability of receiving a splint) were divided into 5 equally sized subclasses based on their rank (ie, patients with the lowest propensity scores in the first subclass, patients with the highest propensity scores in the fifth subclass). Then the success of the model at achieving balance on the covariates was evaluated by looking at withinand across-subclass differences between splinted and nonsplinted patients for each covariate (using analysis of variance or logistic regression as appropriate). The initial main effects model that included all the covariates alone (and no interactions) did not result in balance defined as no significant main effects for splinting or interaction effects of splinting and subclass on all covariates. This model was refined by adding clinically reasonable and/or statistically significant covariate interactions. The final model, presented in table 2, includes all significant main effects, plus the main effects used in the included interactions. By using this model, balance was achieved on all covariates, meaning that, within propensity score subclasses, there were no remaining statistically significant differences between splinted and nonsplinted patients on any of the covariates. Figure 1 displays side-by-side boxplots of the propensity scores for splinted and nonsplinted patients within each of the 5 subclasses. The degree of symmetry in the medians, the similarity in the size of the boxes, and the length of the whiskers further support the adequacy of the final propensity score model for reducing pretreatment differences on observed covariates. Finally, to estimate outcome differences between splinted and nonsplinted patients while controlling for background covariates, the within-subclass means and standard errors (SEs) for the 2 groups were calculated and then used to compute overall differences and standard errors. 28,33 The outcomes of interest were the percentage of cases put on limited duty or taken off work by the treating provider (as distinct from the percentage of patients who elect to take off work or are taken off work by their employers), treatment duration (from the first date of service to the last date of service), the percentage of patients who completed their care in the network (eg, released from care to full duty by the network vs opting out), and the percentage of paients referred to specialists. Limited duty rates, lost time rates, and treatment durations are standard measures of the effectiveness of medical management in workers compensation cases. Treatments that minimize these measures while improving patient function and symptoms are preferred. Referral to a specialist generally indicates the failure of conservative treatment efforts to yield adequate improvement. The final outcome, completion rate, is potentially indicative of patient and/or employer satisfaction with care, in addition to success of care. If large disparities in completion rates exist between treatment groups, the treatment with the higher completion rate would be preferred (assuming the treatment is effective). In addition to the main hypothesis, splinting versus not splinting, the effect of PT was also assessed. The medical model of the network in our study favors aggressive therapeutic interventions including strength training, patient education, manual therapy, and electrotherapeutic modalities so the splinting effect needed to be measured in the presence or absence of PT interventions. Propensity scores for splinting were reestimated separately for patients who did and did not receive PT. For patients who received therapy, the lag from initiation of the episode of care to the initiation of PT was also included as a covariate in the model. Models were estimated and evaluated for adequacy of covariate and overall score balance by using the methods described earlier for the main comparison. Not all the same main effects and interactions were included in these models, although balance on all the covariates and the resulting estimated propensity scores were verified. The within-subclass means and SEs were then calculated and used to assess the splinting effect for patients with and without PT. RESULTS Splinting Main Effect Table 3 summarizes differences in outcome measures for patients with and without splints. Means and SEs for each outcome measure are presented for splinted versus nonsplinted patients within propensity score subclasses and averaged across subclasses. Significance test results, noted in the last row of the table, refer to the overall mean difference observed for splinting versus not splinting (calculated as a 2-tailed z test, significant at P.05).

4 1084 SPLINTING AND EPICONDYLITIS OUTCOMES, Derebery Table 2: Logistic Regression Model Estimates for Propensity to Receive Splint Covariate Estimate SE Wald z Score df P % with high severity (SEV) Patient age (AGE) Marital status (MSAT) Gender (% male) % treated within 1wk of injury % with lateral epicondylitis % initial provider physician (TYPEPROV) % with prior case (PREVIOUS) REGION REGION (1) REGION (2) REGION (3) % with initial drug screen (DRUGSCRN) AGE by DRUGSCRN TYPEPROV by REGION TYPEPROV by REGION (1) TYPEPROV by REGION (2) TYPEPROV by REGION (3) PREVIOUS by REGION PREVIOUS by REGION (1) PREVIOUS by REGION (2) PREVIOUS by REGION (3) TYPEPROV by REGION by PREVIOUS TYPEPROV by REGION (1) by PREVIOUS TYPEPROV by REGION (2) by PREVIOUS TYPEPROV by REGION (3) by PREVIOUS MSTAT by SEV Constant NOTE. Hosmer and Lemeshow goodness of fit: test 4.39, P.820. Omnibus model 23 test , P.001. Abbreviation: SE, standard error. Overall significant differences between splint groups were found for rate of limited duty, number of medical visits, medical charges, total primary care charges (includes PT), and Fig 1. Boxplot showing balance of propensity scores within subclasses. Confidence interval is 99%. treatment duration. Patients with splints had higher rates of limited duty within each subclass and overall (range, 7% 20%) than nonsplinted patients. Typical duty modifications and restrictions prescribed by the treating physician involved lifting restrictions and limitations on time spent doing forceful or repetitive tasks. Patients with splints also had an average of 1 more medical visit within and across all subclasses, higher medical charges (expected given the additional medical visit), higher total charges (PT plus medical), and treatment durations that were an average of 12 days longer than patients without splints. Differences in rates of lost time, the percentage of patients completing care, and the percentage of patients referred out to specialists were not statistically significant. These results do not suggest an advantage for splinting from an outcomes perspective. With the adjustments included for pretreatment differences, these results suggest that splinted patients had worse outcomes in terms of treatment duration, return to activity, and medical costs without improving rates of care completion than did patients without splints. However, the significant differences in total charges (which include therapy charges) do suggest a need for further investigation of the hypothesis that therapy interventions contribute to higher costs and longer treatment durations. Splinting and Therapy Table 4 exhibits outcome differences for splinting and not splinting in patients who did not receive PT. Means with SEs are presented within and across subgroups for each outcome measure. Overall significance results are presented in the bottom row for each outcome variable. Significant differences

5 SPLINTING AND EPICONDYLITIS OUTCOMES, Derebery 1085 Subclass Splint Table 3: Estimated Outcome Differences Between Groups, Splint Versus No Splint* No. of Patients % Ltd Duty % Lost Time Avg MD Visits Avg MD Avg Total % Completed Care (full duty release) Avg Treatment Duration % Refd Out to Specialist 1 No Yes No Yes No Yes No Yes No Yes Overall No Yes P.01 NS P.01 P.01 P.01 NS P.01 NS NOTE. Values mean SE unless otherwise indicated. N Marital status, which was included in the propensity score estimation, was not provided by 19 patients. Thus, their propensities were not estimated and included in this set, although they were included in later analyses. Abbreviations: Avg, average; Ltd, limited; NS, not significant; Refd, referred. *Subclasses of equal size were created according to the ranked propensity score; within subclasses, patients with and without splints have similar propensity scores; overall estimates were produced using direct standardization methods with subclass total weights. 34,41 were again observed for rates of limited duty, number of medical visits, and medical charges. As with the overall results, outcome differences did not favor splinting. Patients without splints were less likely to have limited duty, had fewer medical visits, and had lower medical charges than their splinted counterparts. However, no differences in treatment duration were observed, in contrast with the overall results presented in table 3. Table 5 presents analogous comparisons for splinting and not splinting in patients who received PT. Again, statistically significant differences in limited duty rates, medical visit counts, and medical charges were observed, and worse outcomes for splinted patients were shown. In addition, splinted patients received an average of 1 more therapy visit than nonsplinted patients and had higher overall charges for therapy. The total treatment duration difference was not significant, which suggests that additional therapy, either alone or in combination with additional medical visits, may be responsible for the differences in treatment duration observed in the overall population. But the consistency of results independent of therapy suggests that splinting does not promote, and may even impede, optimal outcomes. DISCUSSION A treating provider s main reasons for prescribing a splint are, presumably, to rest the arm and to alleviate pain or discomfort. However, no good correlation between a patient s subjective pain ratings and his/her ability to work or to perform certain physical activities has been established, nor has a correlation been found between the decrease in symptoms and the rate of return to work. 34,35 In addition, prescribing a splint is likely to necessitate movement restrictions that may further impede recovery and contribute to disability in those cases in which the job activities, which may lead to discomfort, do not actually cause the condition. Such restrictions can have an Subclass Splint Table 4: Estimated Outcome Differences Between Groups, Splint Versus No Splint for Cases Without PT* No. of Patients % Ltd Duty % Lost Time Avg MD Visits Avg MD Charges ($) % Completed Care (full duty release) Avg Treatment Duration % Refd Out to Specialist 1 No Yes No Yes No Yes No Yes No Yes Overall No Yes P.05 NS P.01 P.01 NS NS NS NOTE. Values mean SE unless otherwise indicated. *Subclasses of equal size were created according to the ranked propensity score; within subclasses, patients with and without splints have similar propensity scores; overall estimates were produced using direct standardization methods with subclass total weights.

6 1086 SPLINTING AND EPICONDYLITIS OUTCOMES, Derebery Table 5: Estimated Outcome Differences Between Groups, Splint Versus No Splint for Cases With PT* Avg PT Avg PT Visits % Refd Out to Specialist Avg Treatment Duration % Completed Care (full duty release) Avg Total Avg MD No. of Patients % Ltd Duty % Lost Time Avg MD Visits Subclass Splint 1 No Yes No Yes No Yes No Yes No Yes Overall No Yes P.05 NS P.01 P.01 P.01 NS NS NS P.01 P.01 NOTE. Values mean SE unless otherwise indicated. *Subclasses of equal size were created according to the ranked propensity score; within subclasses, patients with and without splints have similar propensity scores; overall estimates were produced using direct standardization methods with subclass total weights. adverse impact on the patient, not only physiologically but also psychologically. 36 Splint use sends a powerful message, not only to the patient but also to family and colleagues, that the patient has an injury and that the injured arm needs to be rested. Because good physical conditioning is helpful to the healing process of nontraumatic injuries as well as to job performance under healthy circumstances, it is all the more important to consider carefully both the risks and the benefits of splinting. Our study used patient data collected by a large occupational medicine network to explore the effects of splinting versus not splinting on outcomes for epicondylitis patients. Pretreatment differences in observed demographic and initial injury characteristics were identified and controlled for by using propensity score methods. The obtained results suggest that the presumed benefits of splinting commonly including alleviation of discomfort, cushioning of the area, and support of weakened muscles may not translate to better outcomes. Rather, splinting appears to be related to higher treatment utilization and costs and higher rates of duty restrictions (which translate to higher indemnity costs for workers compensation cases) than not splinting even after adjusting for important pretreatment differences, such as severity, age, injury history, geographic region, and other characteristics. The results of our study are consistent with research on activity restriction reported for other types of musculoskeletal injuries. Back pain studies have found that patients who remain active despite back pain do better than those who rest. 37,38 Similarly, it has been reported that, in chronic back pain patients who experience increased pain during the first month of a strenuous exercise program, if they are told to continue performing the exercises anyway despite pain, they go on to have better outcomes than patients whose treatments involve less vigorous activity. 39 In another study, 40 patients with rheumatoid arthritis who were placed on an intensive, dynamic exercise program had better joint mobility, muscle strength, and physical conditioning than patients whose treatments were less intensive. 40 These studies represent a sample of a growing trend in almost every medical discipline toward early activation in injury management. A limitation of this study is its retrospective design, which restricts certainty about the causal relationship between splinting and outcomes. In a randomized controlled trial (RCT), pretreatment differences between patients are randomly allocated among treatment and control groups, so balance on both observed and unobserved characteristics is assured. Although propensity score methodology was used here to successfully balance splinted and nonsplinted patients on all available (observed) pretreatment differences, unobserved differences, by definition, were not controlled for. To the extent that an important predictor of splinting and outcomes was not available for consideration, and particularly if this omitted characteristic does not correlate with the variables included, propensity scores may not have adequately removed selection bias from splint allocation (eg, the differences in patient or treatment conditions that may have influenced both splinting decisions and outcomes). The sensitivity of the splint and no-splint results was evaluated by looking at patients who received PT separately from those who did not. The contribution of therapy can be interpreted in 2 ways. First, the sports medicine model of this occupational network emphasizes early, aggressive therapeutic intervention to achieve optimal outcomes. Therefore, as far as differentially pairing treatments for patients with and without splints, it seems possible that patients without splints would receive PT sooner. A statistically significant association between splinting and lag to therapy was observed in the study

7 SPLINTING AND EPICONDYLITIS OUTCOMES, Derebery 1087 population 91% of patients without splints started PT within a week of beginning care versus 88% with splints. To the extent that early therapy makes a difference in outcomes and correlates with splinting decisions, the observed differences could have been incorrectly labeled as splinting effects. Second, the measure of severity used in the propensity score model was dichotomous and, as such, might not achieve fine discriminations between patients of differing injury severity. But patients with mild severity were less likely to be referred to a physical therapist for supervised exercise sessions or application of modalities and were more likely to be given instructions on a home exercise regimen. The fact that differences between splinted and nonsplinted patients persisted independent of receipt of therapy services offers some evidence that the differences have been appropriately labeled and that reduction of selection bias because of severity has occurred. Another limitation of this study is that differences between types of splints were not assessed. The main hypothesis of this study was that any type of splint involves restriction of movement and would result in longer treatment durations, higher costs, and more time away from work than no splint at all. By extension, under this hypothesis, splints creating greater restriction of movement and worn for longer periods of time might result in worse outcomes than splints with less restriction of movement worn for shorter periods of time. These questions were beyond the scope of our analysis but would make for informative future follow-up investigations. CONCLUSIONS The challenge in occupational medicine, particularly with respect to workers compensation, is for providers to maximize the health and well-being of their patients while showing their cost-effectiveness to employers and payers in the present environment of ever-escalating medical costs. Critical to the success of such efforts is an evaluation of what works because cheaper procedures are not cost-effective if they inflate total medical and indemnity costs by prolonging treatment duration and increasing duty restrictions and time off work. The findings of our study provide evidence that splinting epicondylitis patients does not necessarily lead to better outcomes and, in fact, may have adverse effects. Splinted patients had higher rates of limited duty, more medical visits, higher medical costs, and longer treatment durations than similar patients without splints. Nonetheless, these results should not replace high-quality RCTs of splinting; rather, they should encourage their conduct, to determine under what conditions or for which patients, if any, splinting produces better outcomes, including long-term function and productivity. Additional studies might also address what treatment approaches tend to be paired with splinting versus not splinting in practice, to verify that the effect observed is correctly attributed to splinting. 41 Finally, the effects of splinting decisions on actual versus prescribed absences from work, objective measures of patient function, recurrence of symptoms, and patient satisfaction with treatment should be assessed. References 1. US Bureau of Labor Statistics. Repetitive tasks loosen some workers grip on safety and health. Washington (DC): BLS; Aug Available at: Accessed November 29, Gerr F, Letz R, Landrigan P. Upper-extremity musculoskeletal disorders of occupational origin. 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