It is critical to understand the underlying mechanism of knee osteoarthritis (OA) pain in
order to effectively manage knee OA. It has become clear that alterations in central and
peripheral nervous system functioning occurs in people with knee OA and pain
sensitization is a common feature. Descending modulation from the central nervous system
can facilitate or inhibit nociception. Endogenous pain modulation through the descending
system is an important factor as its dysregulation has significant ramifications in pain
facilitation and promotion of chronic pain development and maintenance at all levels of
the nervous system. The current guidelines lack focus on how to effectively manage it,
which is a potential reason for why the current methods in conservative management of
knee OA pain are only moderately effective. Mind-body approaches are uniquely positioned
to potentially reverse the sensitization, induce positive neuroplastic changes, and
improve descending pain modulation resulting in decreased pain intensity in many chronic
pain populations. This study involves an exercise program which the investigators call
'Pain Informed Movement' that includes evidence-based exercises combined with mind-body
techniques and pain neuroscience education. The data from this phase will be used to
inform a multi-site randomized controlled trial (RCT) to assess the program's
effectiveness with the primary outcome of change in pain severity mediated by change in
descending pain modulation.
Exercise is regularly used as a first-line management option for knee OA, and its use is
supported by high quality evidence to improve pain and function. Clinical practice
guidelines for people with knee OA recommend the use of aerobic and strength training for
the reduction of pain and improved physical function. Currently, one of the key
components of conservative management of knee OA often implemented by clinicians is a
type of exercise called neuromuscular exercise, which aims at improving sensorimotor
control and the functionality of the knee joint by addressing movement in all three
movement planes. Previous research has showed that the neuromuscular exercise programs
designed specifically for knee OA can reduce pain, improve function, alter knee
biomechanics, and improve the muscle-activation patterns of the surrounding knee
musculature. While exercise is the first line treatment for knee OA and can lead to
improvements in physical function and pain, it is important to highlight that it has a
moderate effect, which may be short term.
In recent years multiple guidelines for non-surgical management of knee OA have begun to
include mind-body therapies, such as yoga or tai-chi, as conditional or core treatment
recommendations. Mind-body therapies can lead to pain reductions and improvement of
function through various techniques. For instance, breathing exercises including breath
awareness and regulation can activate the parasympathetic nervous system and decrease the
danger signals of pain, leading to improvement of pain levels. Meditative breathing can
lead to reductions in pain levels by modulating the somatosensory cortex. Relaxation
techniques focused on relaxing the muscles that become tense as a result of pain and by
association can re-enforce or aggravate pain, can influence the pain experience by
reversing that association. Mindfulness meditation and mindful movement which can lead to
a switch from sensory pain to the interoceptive awareness of the movements of the
different body parts, resulting in reduced muscle tension, improvements in postural
stability and proprioception, and reductions in pain levels. Mind-body therapies also
lead to improvement of psychological factors such as depression, anxiety, pain
catastrophizing, increasing pain acceptance, changing patients' relationships to their
pain, which in turn lead to reductions in pain levels. The positive effects of
mindfulness practices have been reported to last in longer-term follow ups such as 15
months, and 3 years.
Education is another core component recommended by clinical guidelines and known to be
effective particularly when combined with exercise. Pain Neuroscience education (PNE) is
an alternative technique of teaching patients about pain and how to rethink and
re-evaluate the way pain is viewed. The use of PNE in physical therapy interventions has
been steadily increasing due to its positive effects on pain and function in many chronic
pain patient populations. PNE includes an explanation of the neurophysiology of pain and
its process by the nervous system. This includes how pain can be modulated through
upregulation or downregulation of signals to increase or decrease the pain experience and
that these changes are not necessarily related to tissue damage, particularly when pain
becomes chronic. PNE also provides information regarding the influence of various
psychosocial aspects. By offering avenues to reconceptualize pain as a threat to the body
and movement as imminent danger, patients may become more willing to participate in
physical activity and tolerate slight increases in pain and discomfort.
In contrast standard OA education is the traditional and most widely used educational
model in people with knee OA, focuses heavily on a pathoanatomical perspective of pain
referring mainly to anatomy, biomechanics, and patho-anatomy of OA and the knee joint.
Given the importance of finding effective management strategies for pain modulation in
people with knee OA, there is a need to further our understanding of the impact of
evidence-based exercise combined with mind-body techniques (e.g., breathing exercises and
mindfulness) with PNE on pain mechanisms.
The study is a pilot RCT with a nested qualitative component. The study will be guided by
the Conceptual Framework for Defining Feasibility and Pilot studies and the Standard
Protocol Items: Recommendations for Intervention Trials.
Study Population
A sample of 66 adults will be sought. The sample size is based on the primary outcome of
complete follow-up using the confidence interval method for calculating sample size in
pilot trials. 90% follow-up rate is the aim but the trial will be considered successful
if 81% is achieved. To achieve a margin of error of 9%, with 10% added for attrition, 66
participants is required.
Recruitment Participants will be recruited through the email lists of the McMaster
Physical Activity Centre of Excellence (PACE) community and the McMaster Institute for
Research on Aging (MIRA) newsletter. Postings will be placed on both PACE and MIRA social
media pages. In addition, the study poster will be placed on other social media channels
(i.e., Twitter, Facebook advertisements). In addition, flyers will be placed in local
orthopaedic surgeon, Rheumatologist and Physiatrists offices. Physicians will provide
potential participants with a one-page study information sheet in lay language. If
interested, potential participants can then contact the research team through the contact
information provided in the flyer.
Setting The in-person 8-week exercise program will be held twice weekly at McMaster
University's Physical Activity Centre of Excellence (PACE) located in the Ivor-Wynne
Centre or in one of two local community churches. Participants will complete the pain
assessment, and have blood drawn at PACE by PACE staff who are certified phlebotomists.
Assessment As part of participation in the study, participants will be asked to attend an
assessment at the beginning of the study, and once again upon completing the 8-week
exercise program. Participants will conditioned undergo pain modulation (CPM) and
mechanical temporal summation testing, and the 30 Second Sit to Stand Test to determine
leg strength and endurance. Lastly, participants will have their blood drawn (fasting) at
the beginning and end of the study. Participants will then be asked to complete a series
of questionnaires about their pain and mood.
Interventions Twice weekly group exercise sessions will be 75 minutes for the
intervention group and 60 minutes in duration for the control group. The intervention arm
class is slightly longer due to the detailed delivery of instructions for the techniques
during the class. Participants will be given instructions to complete these exercises at
home at least one other time during the week for the same duration. Participants will
receive education videos that are ~15-20 minutes each week, for up to 4 weeks.
Pain Informed Movement and PNE - During the neuromuscular exercise sessions, the PNE
components and concepts such as mindfulness, muscle tension regulation, and breathing
techniques will be applied by the instructor.
Neuromuscular exercise and standard OA education - The exercise component (i.e., the
specific movements) of this group will be similar to those of the intervention group
without the added mind-body techniques.
Randomization and allocation concealment Participants will be randomized with an
allocation ratio of 1:1 into one of two treatment groups (Pain informed movement and PNE
versus neuromuscular exercise and standard OA education) using a REDCap randomization
module. Following consent and completion of baseline assessment, the assessor (different
person than the recruiter) will log in to the website, open the participants'
identification record and click on the randomize button. Randomization will be blocked
and this process will ensure allocation concealment. As allocation concealment occurs
following the baseline assessment, the assessors will be blinded at baseline and follow
up assessment. Blinding of instructors is generally not possible in studies of physical
interventions (i.e., exercise). Participants will be blinded to study hypotheses and the
two treatment groups. As both arms of the study are providing exercise based
interventions and education, participants will be provided limited details of each
intervention arm so as to blind them from knowing which is the intervention and which is
the control. This will help minimize any bias that occurs by knowledge of group
assignment and perception of treatment effects.
Exit Survey and Focus Group In addition to the primary and secondary outcomes, a
satisfaction survey will be conducted at the end of the program to evaluate the a priori
feasibility criteria. Participants who indicated upon initially consenting to the study
that would like to participate in a focus group, will be contacted. Qualitative data
collection will be used to explore participants experience and perceptions of the
feasibility and acceptability of the program. A focus group will be conducted using audio
or video recording (using Zoom), lasting between 45-60 minutes.