Problem and hypotheses:
In 2019, the proportion of Canadians aged 55 and over who were employed was 35.9%, the
highest rate recorded to date since 1976. Despite their willingness to remain employed,
seniors are more prone to work disability and early retirement. Older workers with
disabilities are particularly vulnerable to job retention. In Quebec, the average length of
absence following a work-related injury is 134 days for workers aged 55 and over, while it is
less than 50 days for those aged 15 to 24. This difference can be explained in part by the
presence of persistent pain that disproportionately affects older individuals and can
significantly impede rehabilitation to work. The indirect costs associated with unemployment
and absenteeism of people living with chronic pain were estimated to be $22.5 billion in
Canada in 2019. A recent review conducted and published by our team found that strategies to
reduce pain are one of the most important elements to consider in enabling workers to remain
in the workplace after an episode of musculoskeletal disorder.
Exercise plays a central role in chronic pain management and work rehabilitation. However,
pain can be a major barrier to physical activity. Therefore, finding ways to reduce pain
during and after exercise is essential to facilitate rehabilitation. Peripheral
neurostimulation (TENS) - an electrotherapeutic modality that uses an electrical current to
depolarize peripheral nerve fibers with electrodes applied directly to the skin - is
effective in temporarily relieving pain. It represents an interesting avenue for increasing
exercise tolerance associated with exercise in the pain subject. To date, 3 studies have
investigated the use of TENS during exercise, all showing positive results. None, however,
have yet investigated this strategy (TENS + exercise) in aging workers living with persistent
pain.
We postulate that telerehabilitation treatments (therapeutic exercises) provided concurrently
with actual TENS will be more effective in reducing the biopsychological impacts of pain than
the same rehabilitation treatments paired with placebo TENS. Thus, our hypothesis is that the
experimental treatment will cause participants to enter a "virtuous circle": the TENS will
allow for a punctual reduction of pain and kinesiophobia, which will encourage the
realization/resumption of activity and lead to sustained benefits (e.g., physical function,
pain, mood).
Objectives:
The primary objective of this pilot study is to explore the feasibility and acceptability of
using real TENS, compared to placebo TENS, as a complementary treatment to a
telerehabilitation exercise program, in workers who are off work.
The secondary objective is to compare the effect of the two types of intervention (real TENS
- exercises vs. placebo TENS + exercises) on clinical outcomes (e.g. pain intensity,
functioning in vocational rehabilitation, etc.).
Methods and analysis:
Design:
This project consists of a randomized controlled trial following a quadruple blind design.
Participants:
The target population is aging workers who are off work due to a musculoskeletal injury.
Sampling and recruitment procedures:
Participants will be recruited at the ISO-SANTÉ and Physio-Atlas clinics in Sherbrooke, which
specialize in work rehabilitation (volunteer, non-probability sampling). The recruitment of
individuals will be done through posters and with the help of clinicians who will be invited
to talk to patients about the project.
Conduct of the study:
The purpose of this study is to recruit 24 participants who will take part in an exercise
program spread over 3 weeks, with 3 sessions per week. The duration of each session is 30
minutes. The exercise program will be determined by the research team, in collaboration with
clinic health professionals, and the exercises will be delivered via the TeraPlus
telerehabilitation platform. The TENS (real or simulated) will be worn by participants
throughout their telerehabilitation exercises, under the supervision of the student
researcher.