Journal of Rehabilitation Medicine 51-3 | Page 55

J Rehabil Med 2019; 51: 201–208 ORIGINAL REPORT RADIAL EXTRACORPOREAL SHOCK WAVE DEVICE APPEARANCE DOES NOT INFLUENCE CLINICAL OUTCOMES: A RANDOMIZED CONTROLLED TRIAL Antoni MORRAL, PT, PhD 1 , Gerard URRÚTIA, MD, PhD 2 , Ignasi GICH, MD, PhD 2 , Reme RUIZ, PT 3 and Xavier BONFILL, MD, PhD 2 From the 1 Blanquerna School of Health Sciences, Ramon Llull University, 2 Iberoamerican Cochrane Centre, Institut d’Investigació Biomèdica Sant Pau (IIB Sant Pau), CIBERESP, Universitat Autònoma de Barcelona (UAB), Barcelona and 3 Salut i Esport Rehabilitation Center, Santa Perpètua de Mogoda, Spain. Objective: To determine whether the appearance of a radial extracorporeal shock wave device affects clinical outcomes in chronic plantar fasciitis. Study design: Randomized controlled parallel asses­ sor-blinded clinical trial. Material and methods: A total of 135 patients were assigned to 3 groups: group I, standard radial ex­ tracorporeal shock wave device; group II, standard radial extracorporeal shock wave device modified to give a more sophisticated appearance; group III, standard radial extracorporeal shock wave device modified to give a more austere appearance. The radial extracorporeal shock waves emitted by the 3 devices were identical. Primary outcome was foot function, measured with the Foot Function Index. Secondary outcomes were pain at different times, measured with a visual analogue scale, and plantar fascia thickness, measured with ultrasound. Results: All variables decreased significantly from baseline assessment, in all 3 groups and at all time- points: 1, 2, 4 and 14 months after the last session (p  < 0.001). There were no significant differences between groups for any of the variables assessed. Conclusion: Device appearance had no statistically significant influence on clinical outcomes in patients with chronic plantar fasciitis treated with radial ex­ tracorporeal shock wave therapy. Key words: placebo effect; nocebo effect; plantar fasciitis; shock wave, therapeutic context. Accepted Dec 18, 2018; Epub ahead of print Jan 22, 2019 J Rehabil Med 2019; 51: 201–208 Correspondence address: Antoni Morral, Blanquerna School of Health Sciences, Ramon Llull University, 08025 Barcelona, Spain. E-mail: an- [email protected] P lantar fasciitis is the most common cause of inferior heel pain. Typical symptoms include pain with the first weight-bearing step in the morning. Diagnosis of plantar fasciitis can be made clinically (1). The inci- dence and prevalence of the condition are not fully known; however, it is estimated that, in the general population, 1 in 10 people will experience plantar fasciitis at least once in their life (2). Although the suffix “-itis” implies an inflammatory condition, mounting evidence indicates that this foot disorder is associated with degenerative changes and LAY ABSTRACT The context and environment in which treatment is ad- ministered is highly relevant. Context variables are per- ceived and interpreted by patients and can generate po- sitive or negative expectations. Such expectations may influence the therapeutic outcome. This study assessed whether a contextual element, such as the external ap- pearance of a shock wave device, influenced clinical out- comes in patients with chronic plantar fasciitis. Three shock wave devices were compared: a standard device; a sophisticated device; and an austere device. The only difference between the devices was their external ap- pearance. The shockwaves emitted by the 3 devices were identical. No differences were found between the 3 devices for any of the variables assessed. Health pro- fessionals and future research into the therapeutic en- counter context should focus more on patient–therapist interactions than on the appearance of devices. should be appropriately classified as a “fasciosis” or “fasciopathy” (3). The causes of plantar fasciitis are multifactorial. It responds well to multiple conservative therapies. The prognosis is favourable, with resolution of symptoms in approximately 80% of cases (4). However, there is no evidence-based consensus on the most effective treatment. Systematic reviews have shown radial extracorporeal shock waves (rESW) to be effective and safe for the treatment of chronic plantar fasciitis (5–7). The biological effects of rESW are tissue rege- neration, angiogenesis and analgesia (8, 9), produced by a mechanotransduction mechanism by which cells recognize and respond to mechanical stimulation (10). There are many variables, including the placebo effect, which can explain the clinical improvement experienced by patients when they receive a phar- macological treatment or physical treatment, such as rESW (11). The placebo and nocebo responses refer to changes in patients’ symptoms attributable to their participation in a therapeutic encounter and its rituals, symbols and interactions (12). However, other elements, such as patient–therapist relationship, psychosocial factors, and patients’ hopes, beliefs and fears, must also be considered (13, 14). The context and environment in which treatment is administered is highly relevant. Context variables are This is an open access article under the CC BY-NC license. www.medicaljournals.se/jrm Journal Compilation © 2019 Foundation of Rehabilitation Information. ISSN 1650-1977 doi: 10.2340/16501977-2516