Approximately 65% of traumatic injuries occur in individuals aged 18 to 55 years [1], compromising their most productive years of life. Orthopedic lesions, including lower extremity trauma (ET), affect the majority of injured individuals (80%) [1]. More than 50% of patients with major ET (ie, patients at risk of impaired outcomes usually requiring surgical and multidisciplinary team management) report moderate to severe pain at hospital discharge [2,3], which becomes chronic in up to 86% of cases [4,5]. Pain has several negative consequences. Indeed, poorly managed acute pain has been associated with undesirable outcomes, such as delayed recovery and prolonged length of hospital stay [6,7]. Moreover, intense acute pain has been identified as a chronic pain risk factor after traumatic injury [4,5].

Acute pain is of sudden onset and is expected to last a short time, and can usually be clearly related to a specific event, injury, or illness [8], such as major ET. Chronic pain is defined as ongoing or intermittent, lasting beyond the injury healing process (or more than 3 to 6 months), and adversely impacts daily functioning as well as quality of life (QoL) [9,10]. Healing time after lower ET varies according to the extent of osseous and soft-tissue damage, patient characteristics (eg, age, smoking history, nutritional deficiency), and quality of surgical treatments [11,12], but does not usually exceed 3 months in the absence of complications [11].

People with chronic pain report poorer QoL than individuals affected by common chronic diseases of the heart and lungs [13], making it the most frequent reason for seeking medical attention [14]. Up to 60% of active people who live with chronic pain (including those with lower ET) will experience pain interference with daily living activities, which can lead to job loss or reduced professional responsibilities [15]. Chronic pain also imposes a high socioeconomic burden, which has been estimated to be US $635 billion annually in terms of health care costs and lost productivity [16,17]. Given the impact of chronic pain, the Institute of Medicine (IOM) of the National Academies [8] made “pain prevention” the highest priority for pain relief. To do so, the IOM called for the early promotion of patient self-management behaviors and consideration of biological and psychosocial factors to prevent acute to chronic pain transition.

Many longitudinal studies have described chronic pain risk factors. Demographics (eg, female gender, age >65 years, low socioeconomic status) have been shown to play a role in the transition from acute to chronic pain in patients with major ET [4,5]. Moderate to severe acute pain (ie, >4/10 on a numerical rating scale [NRS]) [18] and lower limb trauma are injury-related chronic pain risk factors consistently described in trauma patients [4]. Several potentially modifiable psychological risk factors also seem to be involved, including pain catastrophizing, pain-related fear (ie, kinesiophobia), anxiety, depression, and post-traumatic stress disorder (PTSD) [4,5,19]. However, some patients do not develop chronic pain after ET or other types of injuries, and protective factors have been explored [20,21]. Pain self-efficacy (SE) has been discussed as a protective psychological attribute in acute and chronic pain post-ET [4,22,23]. Pain acceptance has also been associated with improved outcomes in populations that do not include ET patients [24-27].

Interventions based on a cognitive-behavioral approach have been the most frequently-studied [28] treatments addressing potentially-modifiable psychological factors in the context of chronic pain [29]. These interventions are aimed at promoting individual self-management behaviors (eg, skills to control pain and their effects on physical and psychological functioning) when experiencing pain episodes [30,31]. Such objectives are reached through educational, cognitive (ie, prevention or alteration of maladaptive thoughts, problem-solving) and behavioral (ie, relaxation skills, activity pacing, return to pre-injury activities) strategies as well as complementary approaches, such as support (eg, continued monitoring, encouragement) and relapse prevention (eg, self-monitoring and matching of learned self-management behaviors with real-life situations) [32].

A recent systematic review [29] of psychological therapies for chronic pain management concluded that interventions including such strategies were the most effective. Findings revealed small effect sizes (ie, standardized mean difference [SMD] of 0.15 to 0.29) on pain and related disability and moderate effect sizes (SMD of 0.3 to 0.59) on mood and pain catastrophizing compared to standard care or waiting list. However, these tested interventions have been found to have only small positive effects on pain-related disability and pain catastrophizing compared to active controls (ie, physiotherapy, education, or medical regimens). Most of these effects were observed post-treatment but were not maintained at follow-up (ie, 6 to 12 months after treatment).

Considering the refractoriness of chronic pain to treatment, interest has been growing in the development of interventions intended to promote self-management behaviors before acute pain becomes chronic [28]. Some empirical evidence has revealed that interventions could prevent acute to chronic pain transition several months post-injury, mainly in back pain patients [33-43]. However, no such interventions have been tested in patients with major ET.

In this regard, most randomized controlled trials (RCTs) on preventive self-management interventions have been conducted in patients with pain duration varying from 15 days to 3 months, who were treated in primary care settings or hospital outpatient clinics [33-35,37-43]. The main objective in most of these studies was to restore functioning in activities of daily living and work, and to reduce pain intensity. Most interventions included four to six weekly sessions, which lasted 20 minutes to 2 hours, and were delivered face-to-face individually or in-group. Two to four face-to-face booster sessions to promote the sustainability of intervention effects and/or follow-up phone calls were provided in some studies from two weeks to three months after intervention completion [33,40,42]. Psychologists, nurses, and physiotherapists have most frequently provided these interventions. Research on the effects of such interventions reported positive findings related to pain intensity, restoration of daily functioning, social impact, and psychological variables. Indeed, statistically and clinically significant reductions (between 30% to 50% from baseline) of mean pain intensity scores were observed at 3 and 6 months after the onset of acute pain, favoring the group receiving self-management interventions compared to active controls (ie, education, physiotherapy, biofeedback) [34,41]. Similarly, a study in which participants were classified as back pain “recovered” or “chronic back pain” (based on pain intensity and disability cutoff scores) demonstrated that the number of participants who recovered from their back pain was more than twice as high in the group completing a 4-session self-management program compared to the attention control group (54% vs 23%, P=.02) at 6 months [42].

Positive outcomes on work status were also demonstrated in other RCTs documenting that control group participants, receiving usual care or education through written document, were at a 3-to-9-fold greater risk of long-term sick leave (ie, a total of 15-30 or more days in the past 6 months) compared to those receiving the self-management intervention [37-39]. Similarly, patients at risk of chronic back pain showed significant decreases in health care service utilization (ie, self-reported number of visits to physicians or physiotherapists) or were less often referred to multidisciplinary programs for pain at 1-year follow-up when they had received a self-management intervention, in comparison to those who had not.

Furthermore, research findings have shown that the early implementation of self-management interventions designed to increase the patients’ abilities to respond to pain in a more adaptive way contributed to better psychological outcomes. For example, participants who received such interventions demonstrated more positive attitudes towards back pain self-care abilities and significant reductions in pain worry and kinesiophobia at 1-year follow-up [41,43] compared to participants who received education only. Another study showed that participants who received a self-management intervention exhibited less maladaptive behaviors (eg, self-blame) and more adaptive behaviors (eg, problem-focused) [36]. In this regard, experimental group participants were less depressed than the control group subjects, who were 7 times more likely to develop psychopathologies (ie, anxiety, sleep and somatoform disorders) at 1-year follow-up.

Based on knowledge acquired from positive outcomes associated with early self-management programs, we have designed a self-management intervention to prevent acute to chronic pain transition after major lower extremity trauma (iPACT-E-Trauma). Specifically, the intervention focuses on reducing pain intensity and pain interference with daily living activities, to maintain scores <4/10, as recommended by the Initiative on Methods, Measurement, and Pain Assessment in Clinical Trials (IMMPACT) for chronic pain prevention [44]. Patients with an injury to a lower extremity have clinical conditions, recovery profiles, and continuum of care that are different from patients with back pain, necessitating the development of an intervention that fits their specific needs. For example, ET injuries and movement limitations immediately after trauma require the administration of targeted pharmacological and nonpharmacological strategies (ie, cryotherapy, legs being elevated) to reduce inflammation and acute pain in the first intervention sessions, instead of focusing on restoring function. Moreover, ET patients are hospitalized in acute care settings before being transferred to an inpatient and/or outpatient rehabilitation center. The ET patients’ capacity to participate in self-management intervention while in these settings must be considered when selecting the intervention’s dose (ie, duration and number of sessions) and delivery modes. Similarly, the evolving ability of ET patients to bear weight on their injured limb must be considered when guiding them in their return to previous activities, and in the application of pain management strategies (eg, restarting the use of analgesics and cryotherapy for a few days when initially bearing weight on the injured limb).

Empirical and clinical data have guided the development of a preliminary version of the iPACT-E-Trauma intervention, which was refined after the assessment of its acceptability by clinicians (nurses, orthopaedic surgeons, a family physician specialized in pain management, a psychiatrist and physiotherapists) and patients (unpublished observations; Bérubé, Gélinas, Martorella, Feeley, Côté, Laflamme, Rouleau, Choinière; under review). Clinicians and patients positively evaluated the acceptability of the preliminary version of iPACT-E-Trauma. To further improve the suitability (ie, how easy the intervention is applied in the context of daily life) and convenience (ie, willingness to participate in the intervention) [45] of the iPACT-E-Trauma intervention, procedures for the documentation of self-management behaviors by patients were simplified, and session durations were reduced (ie, 15 minutes instead than 30 minutes) as recommended by clinicians. Acceptability assessment of the iPACT-E-Trauma intervention by patients allowed for the tailoring of iPACT-E-Trauma key features based on determinants such as pain intensity, previous knowledge, and the application of self-management behaviors. Furthermore, based on clinicians’ and patients’ input, a Web application was developed to facilitate the intervention delivery in acute care settings. In this paper, an RCT protocol is described to pilot test the refined iPACT-E-Trauma intervention, which is required before evaluating its efficacy in a full-scale multi-site RCT.

We hypothesize that the experimental group will experience a clinically significant reduction of pain intensity (ie, >2 points on a 0-10 NRS) [46] and pain interference with daily living activities (ie, >1 point on a 0-10 NRS) [46] compared to the control group at 6 months post-injury. We expect that the participants in the experimental group will also present higher rates of no pain or mild pain intensity and/or pain interference scores (ie, <4/10) [44] on these two outcomes. Secondly, we hypothesize that the experimental group will present increased pain SE and pain acceptance as well as reduced pain catastrophizing, pain-related fear, anxiety and depression symptoms, health care service utilization, and increased return to work compared to the control group at 6 months post-injury.

A 2-arm single-blind pilot RCT will be used. Participants will be randomized to either an experimental group (iPACT-E-Trauma intervention and usual care) or control group (educational pamphlet and usual care) and followed according to the study time points (T1 to T8) presented in Figure 1. The Standard Protocol Items on Recommendations for Interventional Trials (SPIRIT) will be followed [47], per the checklist presented in Multimedia Appendix 1.

The study will be conducted in a level-1 academic trauma center in Montreal, Canada. The intervention will be provided to the experimental group during their hospitalization in the level-1 trauma center and after hospital discharge. The control group will receive an educational pamphlet while in the trauma center.

The inclusion criteria will be: (1) age 18 years or older; (2) able to read and speak French; (3) have a major ET; and (4) at risk of developing chronic pain. Several chronic pain risk factors have been identified in patients with major ET, with acute pain intensity found consistently in this population. IMMPACT has recommended the consideration of this inclusion criterion in chronic pain prevention studies [44]. Patients will be enrolled if they present pain intensity >4/10 upon movement 24 hours post-injury. Waiting 24 hours post-injury to enroll patients will allow their pain intensity to be adequately documented, and will allow us to determine if they are at risk of chronic pain before the administration of the intervention. Considering that lower ET has been identified as a chronic pain risk factor (and to optimize sample homogeneity) only patients with such injuries will be recruited.

The exclusion criteria among ET patients will be: (1) spinal cord injury; (2) other trauma associated with high-intensity pain (eg, >2 rib fractures [48] or surgical abdominal trauma [18]) or principal site of pain not being lower ET; (3) amputation; (4) cognitive impairment (eg, dementia, severe psychiatric disorder, Glasgow Coma Scale score <13/15) [49]; and (5) >7 days of hospitalization. This last criterion was established to minimize delays in intervention delivery, and to standardize intervention timing. Since traumatic injuries occur more frequently in older adults [50], pre-injury somatic pain (eg, pain caused by joint osteoarthritis) will not be an exclusion criterion unless patients report daily analgesic use prior to the trauma. Likewise, patients with a history of visceral pain (eg, inflammatory bowel disease) will not be excluded, considering that this type of pain can be differentiated from musculoskeletal pain caused by a lower ET. Although substance abuse may influence the intervention’s outcomes, this comorbid factor will not be an exclusion criterion. The prevalence of alcohol abuse in patients who have sustained a traumatic injury ranges from 40% to 70% [51-53] and could reach 33% for drug abuse [54]. Excluding patients with a history of substance abuse would impact the external validity of the study. However, data on substance abuse will be collected at baseline and its potential effects on outcomes will be analyzed separately to explain findings, and to inform the research methods of a future full-scale RCT (eg, need for stratified randomization to control for the confounding factor).

A number of variables will be measured at different time points (Multimedia Appendix 2) to meet study objectives based on the SPIRIT statement [47]. Complementary variables will be evaluated to facilitate data interpretation and comparison with other populations.

The sample size of a pilot trial should provide reasonable confidence to guide investigators in their decisions about proceeding to a larger trial. Sample sizes that are too large should be avoided due to costs and ethical issues. An 80% 1-sided confidence interval of estimated main trial effect size has been proposed to achieve such aims [96]. Chronic pain prevention studies are not informative about the effect size that should be used to calculate pilot trial sample size. Hence, the effect size documented in chronic pain trials (SMD=0.25-0.35 [29,58]) regarding pain intensity and pain interference with daily activities (primary variables) was used to calculate sample size, and was estimated to be 23 participants per group [96]. With prevision of a 20% attrition rate often encountered in longitudinal studies [64], a total of 56 participants will be recruited and randomized into each group (experimental and control).

Nurses, medical residents, orthopedic surgeons, and an orthopedic trauma case manager nurse will identify possible participants, inform them about the study, and obtain their permission to be contacted by the principal investigator (PI; MB). These professionals have been informed about the study’s inclusion-exclusion criteria during information sessions. The name and medical file number of patients giving permission to be contacted will be provided to the PI by those who are referring participants via verbal communication or confidential voicemail messages. The PI will then visit these patients. If patients meet the inclusion criteria and wish to participate after receiving a full explanation of the study, the PI will obtain their written informed consent (Multimedia Appendix 5).

Procedures have been implemented to ensure that the information participants provide in this study will be kept confidential. All participants will be assigned a unique code number. Consent forms will be stored separately from the data. A master list matching the names of participants with their study identification numbers will be kept in a locked filing cabinet separate from the data. No names or other identifying information will appear in any data that is generated.

Study findings will be presented in comprehensive form and not linked to specific participants. All hard copies of the data will be stored in a locked filing cabinet in a locked office. Online survey software secured with enhanced login and encryption features will safeguard the electronic questionnaire format. Data from electronic questionnaires will be downloaded onto a password-protected computer hard-drive and onto a safety code-protected Universal Serial Bus key. Data will be deleted from online survey software at the conclusion of the study, but will be stored for 10 years and then destroyed, and treated as confidential waste.

Protocol amendments will be communicated to the Institutional Review Board (IRB) and through additional information in the trial registration form. Finally, the intervention is not known to be associated with any adverse events. However, such events will be documented if they emerge throughout the study.

The aims of this pilot RCT are to evaluate the feasibility and research methods of a chronic pain preventive intervention. Testing the intervention will provide information on its preliminary efficacy while allowing more data to be gathered on its acceptability from the perspective of patients. Chronic pain has repeatedly been identified as an important health problem in patients with major ET, but no intervention has yet been proposed for them. Evidence from such interventions in other populations is scarce. Indeed, a great deal of attention has been devoted to the implementation of interventions when pain has already become chronic, but few studies have focused on its prevention. This RCT could allow for the development of an evidence-based intervention tailored to ET patients’ needs early after injury.

Preliminary testing of the intervention will set the stage for a full RCT, should the results be promising. If a full RCT shows that the intervention is effective, it will provide professionals of multidisciplinary teams working in the trauma-orthopedics field with scientific guidance and a meaningful way in which to address acute to chronic pain transition. The development of self-management behaviors that decrease long-term reliance on the health care system corresponds to current trends put forward by health policies and health organization decision-makers (ie, to empower patients to take responsibility for their own health and make services more efficient) [8]. A feasible and acceptable intervention aimed at preventing chronic pain could ultimately achieve such objectives while helping to reduce the number of patients with major ET disability and associated social costs.

Participation burden is an important limitation of this study. Participants in both groups will be asked to complete numerous questionnaires over a long period of time and participants in the experimental group will also have to attend several intervention sessions. To minimize the risk of attrition related to participation burden, patients will be contacted several times throughout the study by phone or email to complete or remind them to complete questionnaires, which will help maximize continued participation. Participants will receive monetary compensation proportional to the number of outcome questionnaire packages completed and intervention sessions attended (ie, Can $10 per questionnaire package and intervention session). The proposed initial number of participants to be recruited accounts for attrition rates commonly reported in longitudinal studies.

A second limitation pertains to the potential generation of social desirability bias since participants will self-report their performance of intervention activities and self-management behaviors. To minimize this type of bias, participants will be informed that honest answers to questions are crucial for developing interventions that will correspond to ET patients’ needs, and determine if such interventions should be offered to patients with major ET in the future.

The trial was ongoing at the time of the protocol submission. No comprehensive data analyses had begun at the time of this manuscript preparation.

IRB approval was obtained from the Centre Intégré Universitaire de Santé et de Services Sociaux du Nord-de-l’Île-de Montréal - Hôpital du Sacré-Cœur de Montréal (HSCM) in June 2016 (HSCM Project No. 2017-1333; Multimedia Appendix 6). The PI will obtain written informed consent from participants before initiating the study.