The RECLAIM Trial: A randomised controlled trial to test the clinical and cost-effectiveness of a new treatment on the risk of developing chronic post-surgical pain following total knee replacement surgery.

The RECLAIM trial will test the effectiveness of a new intervention called ‘Fit for Purpose Training’ in early post-surgical care following TKR surgery. This new intervention aims to target key cognitive, neurophysiological and peripheral tissue factors to optimise long-term pain and function outcomes after TKR surgery. After surgery, participants in the Fit for Purpose Training group will receive pain science education related to recovery from TKR surgery. They will also receive exercises designed to improve the precision of touch and proprioception, enhance the activation and capacity of muscles around the operated knee and integrate these new skills into functional task performance. This intervention will be provided by a physiotherapist and will involve up to 12 sessions (of approximately 60 minutes) over a 16-week period, supplemented by an e-learning platform. These sessions will focus on individualising the education and exercise to the person. Physiotherapy sessions will be provided in-person either at Adelaide University Clinical Trials Facility (located on the eastern end of North Terrace) or at SAHMRI (located at the western end of North Terrace), Adelaide. If needed, some sessions can also be provided via telehealth. Physiotherapists providing ‘Fit for Purpose Training’ intervention will undergo specialised training, including pilot participants prior to trial commencement to ensure competency. Fit for Purpose Training intervention involves an education component (Rethink), a sensorimotor brain training component (Reset) and a movement and loading component (Reload). During the physiotherapy sessions, pain science education (tailored to the participant) will be provided, as well as instruction and training around the sensorimotor and the movement and loading components, as relevant. Participant’s experiences with these treatment components, barriers to performing them, and any queries/questions will also be addressed during in-person Physiotherapy sessions. The e-learning platform is access by participant outside of Physiotherapy sessions and is used to guide at home training for the Fit for Purpose program (education, sensorimotor, and movement/loading components). The education component is informed by contemporary pain science research about knee osteoarthritic pain. It is specifically informed by The Knee Osteoarthritis Handbook, which is a patient-facing book published by NOIGroup Pty Ltd (Co-authored by PI Stanton). An updated version of this resource, including relevant pain science research regarding surgery and post-surgical recovery and how this relates to core pain science concepts, will be used for the trial. The education component includes in-session content provided by the physiotherapist, supplemented by at-home learning supported by the online platform. The sensorimotor brain training component will include both tactile (touch) training and proprioceptive (sense of location) and motor (movement) training involving the knee. These will be provided in a graded fashion, such that participants progress through the levels over time. Tactile training to the knee will be provided in 3 levels: 1. Localisation (determining the spatial location of a touch stimulus on the knee); 2. Discrimination (determining both the spatial location of a touch stimulus as well as the nature of the stimulus, i.e., sharp or blunt); 3. Graphesthesia (determining more complex patterns drawn on the knee such as letters, numbers or shapes). This training aims to increase the precision of the tactile representation of the knee in the brain, allowing for more precise coding of sensory information, which is associated with reduced pain and with a heightened feeling that the body part is their own and ‘feels right’ (targeting impaired body perception). Tactile discrimination training is recommended for ~15 minutes, once per day. Proprioceptive (motor) training will be provided in 6 Levels: 1. Implicit motor imagery (left/right judgements; identifying whether a pictured image is of the left or the right lower limb) 2. Movement empathy (observation of knee/leg movement through watching videos); 3. Explicit Motor imagery (imagining what it would feel like to do a knee/leg movement); 4. Mirror therapy (watching a reflected image of the non-surgical knee moving – it appears to be the operated knee moving); 5. Precise passive movements of the knee (therapist moves the knee and patient must indicate direction of movement; progresses to patient actively reproducing knee position); 6. Precise active movements of the knee and lower limb, including generation of specific force, specific knee positions or movement patterns Levels 1-4 have been shown to sequentially activate areas of the brain that are involved with movement and help to ‘break’ the association that can occur between pain and movement. They also promote ‘reconnection’ with the knee – feeling like the knee is their own – helping to target impaired body perception. Levels 5-6 are more advanced and aim to train precise capture of limb location, movement and force production – again this helps to promote ‘reconnection’. Patients will progress through these levels over 4-5 weeks. Training dosage is high: aiming for ~5 minutes every waking hour. For both, training is provided and progressed during the in-person sessions and supplemented at home via the online training program (and with partner assistance in some cases). This will include more traditional rehabilitation exercises that involve lower limb strengthening and endurance, such as squats, sit to stand, lunges, side steps, knee extension, heel raises, etc. This will occur later in the treatment program (i.e., following the sensorimotor training component) and will be informed by individual participant goals and delivered in a feedback rich environment to help target impaired body perception. The training of Physiotherapists providing the “Fit for Purpose” training will involve ~8 x 2 hour online modules over 6 weeks, as well as 2-3, ~1 hour group sessions, either face-to-face or online (as required), to allow for questions, clinical practice of the skills, and discussion. Training will be led by CI Stanton/Moseley (pain science education expertise), CIs Wand/Stanton/Harvie (sensorimotor training expertise), and CI Stanton/Wand (movement and loading component). Physiotherapists will undergo a competency assessment involving recorded responses to presented scenarios to interrogate knowledge/ability around intervention content and provision in the trial as well as treatment of a pilot participant, with review of (and feedback provided for) intervention fidelity. If competency is not achieved, further training may be required.