Use of the PREPARE (PREhabilitation, Physical Activity and exeRcisE) program to improve outcomes after lumbar fusion surgery for severe low back pain: a study protocol of a person-centred randomised controlled trial

Lumbar degenerative disc disease (DDD) is a subgroup of chronic low back pain (CLBP). When pain and disability are severe, lumbar fusion surgery can be an option [1]. The frequency of lumbar spinal fusion surgery is increasing worldwide [2, 3]. In 2008, DDD was the most common diagnosis prior to spinal fusion surgery in the USA [4]. In 2013, the Swedish Spine Register recorded 8144 patients with degenerative lumbar spine disorders, of which approximately 10 % had a primary diagnosis of DDD or isthmic spondylolisthesis and underwent lumbar fusion surgery [5]. The DDD group is an interesting study group for several reasons. They are relatively young [5], and their lack of functioning has hence a large impact on their life and on society. Clinical experience dictates that most patients choose fusion surgery to enable them to continue to work and to live an active life.

While rehabilitation traditionally starts postoperatively, the phase before surgery – termed prehabilitation – is suggested to be an ideal time to prepare patients for an optimal outcome of surgery [6, 7]. A small number of studies of low-quality suggest that there is no evidence for the effectiveness of physiotherapy interventions before and after lumbar fusion, and hence best practice remains unclear [8]. We lack guidelines for the pre and post-operative phase for this patient group [9, 10], but there are national and international guidelines for conservative or non-pharmacological treatment for patients with CLBP. These guidelines incorporate major treatment principles, such as to stay active despite pain along with supervised exercise therapy, cognitive behavioural therapy and multidisciplinary treatment [11]. There is no reason to believe that patients with DDD would not benefit from the same treatment principles.

The benefits of staying or becoming more physically active are manifold. The major underlying rationale is the effect of physical activity on general health [12, 13]. On a global level physical inactivity is one of the global burdens, leading to premature death and non-communicable diseases [13]. It is hence important to promote physical activity in all conditions, patients with CLBP alike. Patients with DDD who choose to undergo surgery have experienced pain for several years, and 52 % of them reported that they are able to walk less than one kilometre [3]. However, there are presently little data regarding physical activity levels in this patient group. In addition to its general health benefits, physical activity has an analgesic effect that likely involves several partially overlapping mechanisms [14, 15]. The hypoalgesic effect of exercise on pain is usually reduced in patients with “more general” chronic pain conditions [14]. However, the exercise-induced hypoalgesic effects in patients with CLBP are reportedly similar to those in healthy individuals [16, 17]. It would hence be of value to promote physical activity for patients with DDD.

There are various reasons for not being physically active. One factor is the perception and attitude towards exercises [18]. Another factor is fear of movement. This factor has been identified as an important mediator in combination with catastrophizing thoughts regarding disability, disuse and depression in patients with CLBP [19]. It appeared that 70 % of the patients with CLBP who visited an orthopaedic department in Sweden for a potential fusion surgery reported kinesiophobia [20]. Even though the prevalence of kinesiophobia among patients with DDD is unknown, research suggests that the prevalence of kinesiophobia in patients with specific CLBP is similar to that in patients with non-specific CLBP [21]. Furthermore, pre-surgical psychological status such as pain catastrophizing [22], negative outcome expectations [23] and fear-avoidance beliefs [24] have been found to be significant predictors of pain and function up to 2 years after lumbar surgery. Hence, we hypothesise that the majority of persons who are waiting to undergo surgery for DDD suffers from a high degree of pain, kinesiophobia, catastrophizing and low self-efficacy – and all of these factors may contribute to a low physical activity level. Hence, an intervention using a cognitive behavioural approach could be appropriate to target these risk factors. Given the multidimensional nature of pain, rehabilitation programs based on cognitive-behavioural therapies (CBT) have been specifically recommended for patients with CLBP and are often used in addition to other therapies such as exercise [25].

Although the importance of post-lumbar surgery rehabilitation programs targeting the above-mentioned psychological factors have been emphasised [26‐28], so far only two programs have yielded successful outcomes following lumbar fusion surgery [28, 29]. Abbott et al. compared postoperative psychomotor therapy with exercise therapy in a randomised controlled trial (RCT) that included 107 patients undergoing lumbar fusion surgery for spinal stenosis, spondylosis, degenerative/isthmic spondylolisthesis or DDD. The psychomotor therapy program combined motor control exercises for lumbopelvic stabilisation with a cognitive behavioural intervention immediately after surgery. This treatment was more effective compared to exercise therapy in reducing disability and fear-avoidance beliefs and in increasing self-efficacy and outcome expectancy at 2 and 3 years post-surgery [28]. Another recent RCT compared a rehabilitation program including active exercise alone with a treatment combining active exercise with the management of catastrophizing and fear of movement among 130 patients undergoing lumbar fusion surgery for degenerative spondylolisthesis and/or lumbar spinal stenosis. The combined rehabilitation program showed superior disability reduction measured by the Oswestry Disability Index (ODI) at the 1-year follow-up [29].

These prior investigations have been performed after lumbar fusion surgery. However, some authors hypothesise that further optimisation of lumbar fusion surgery outcomes may be possible by initiating an intervention before surgery [26, 30]. Nielsen et al. found their intervention to be superior to conventional care with regards to postoperative functionality assessed by the Roland-Morris Disability Questionnaire, faster recovery and shorter hospital stay. The content of the intervention was an individualised preoperative training program that focused on improvement of muscular back strength as well as cardiovascular conditioning before spinal fusion surgery [26].

To our knowledge, at the start of our trial (2014), no prior study had assessed the use of a prehabilitation program with individual sessions to target psychological risk factors – such as fear-avoidance beliefs and low self-efficacy – to maintain or increase physical activity both before and after surgery. Therefore, we initiated an RCT to evaluate a physiotherapeutic prehabilitation program called PREPARE (Prehabilitation, Physical Activity and exeRcisE).

The overall aim of our trial is to investigate whether patients experience improved post-operative functioning if they receive a pre-surgical physiotherapeutic prehabilitation program based on a cognitive behavioural approach, as compared to conventional care.

As stated previously, at the time that the present trial was designed, no prior investigation had examined a prehabilitation program with a cognitive behavioural approach. To this date, two studies have been published within the field [26, 30]. We would like to clarify the similarities and differences in order to argue for the added value of our planned trial, PREPARE. All three of the studies were set up with RCT designs, and disability was one of the primary outcomes [26]. Disability is however measured somewhat differently in the various studies. Nielsen et al. used the term functionality, which was assessed by the Roland Morris Disability Questionnaire and two performance-based outcome measures (the Sit-to-stand test and the Timed-up-and-go test) [26]. Rolving et al. used the ODI as the primary patient-reported outcome measure but did not use any performance-based outcome measures of functioning [30]. In PREPARE we use a combination of outcome measures (patient-reported and performance-based outcome measures as well as accelerometer data). We would argue that this will provide a more comprehensive picture of the patient’s functioning as reflected in the International Classification of Functioning, Disability and Health [66].

The intervention programs in the three studies mentioned above vary somewhat in the underlying theoretical models and content. PREPARE is being performed from a person-centred perspective [32]. In concrete terms, it means that we have set up person-centred treatment sessions on a one-to-one basis. This is in line with the trial from Nielsen et al. in which the healthcare professional met the patient on an individual basis before surgery. In their intervention program, the patient met with the physiotherapist on two occasions, at the day of inclusion and two weeks before surgery [26]. In order to gradually challenge the patient’s cognitive beliefs and to facilitate the patient’s self-efficacy in relation to staying active despite pain, we have included four sessions and one booster session.

As argued for in the introduction section, the main principle of our prehabilitation program is to help the patients to stay active despite pain. Both Nielsen et al. and Rolving et al. seem to have built their prehabilitation program on the same principle. Nielsen et al. investigated the effect of an individualised preoperative training program that focused on improvement of muscular back strength as well as cardiovascular conditioning before surgery [26]. Rolving et al., on the other hand, had a stronger cognitive behavioural focus of their intervention program [30]. The relevance of the pre-surgical psychological status is an important determinant of surgical outcome in PREPARE. In accordance with the modified fear-avoidance model, we hypothesise that by trying to influence catastrophizing thoughts and patient’s self-efficacy beliefs to exercise the patients in the intervention group will increase their level of functioning and physical activity level. In addition, in PREPARE we combine cognitive behavioural techniques with physical activity goal setting which we argue is a major strength that will further help the patients to be more active despite pain both before and after surgery.