Effects of Motor Imagery Intervention on Functional Recovery Following Total Knee Arthroplasty
Condition: Osteo Arthritis Knee; Knee Arthroplasty
MeSH terms: Osteoarthritis; Osteoarthritis, Knee
Study type: Interventional

Summary: 
      The knee osteoarthritis becoming a leading cause of disability among older adults'
      population. When conventional treatments fail, a total knee arthroplasty (TKA) is suggested.
      Although TKA treatment significantly reduces pain and improve mobility of patients, there is
      still high prevalence of patients whose neuromuscular function is impaired up to three years
      following TKA, which can be directly prescribed to poor or/and inadequate rehabilitation
      practice. Thus, motor imagery (MI) is proposed as additional rehabilitation tool to
      convention physical therapy to reduce decline of neuromuscular function in early days
      post-surgery. Recent studies showed that MI could facilitate learning and acquisition of
      motor skills, as well as maintain and retain previously acquired motor skills, which may be
      beneficial for those who undergo TKA. It represents an incentive in the process of motor
      learning and the transfer of the mental scheme of the motion pattern into the process of
      movement execution. Measuring neuromuscular function pre- and post-TKA could be unique
      opportunity to provide empirical evidence about its additional therapeutic effects. Outcomes
      of proposed research project could serve to improve existing intervention programs applied in
      rehabilitation protocols following TKA surgery as well as other orthopedic interventions.
      This would also contribute to the successful return of individuals after an injury to their
      everyday working routine. We hypothesized that MI practice group will experience better both
      subjective and objective measures of functional performance compared to control group that
      will be subjected to routine physical therapy only.
    

Detailed description: 
      TKA is widely considered to have a successful outcomes, comparing pre and postoperative
      scores on pain and both subjective and objective functional measures. Nevertheless, a
      significant proportion of patients report continuing pain, functional limitations, and
      dissatisfaction up to three years after the surgery. Thus we planed to conduct intervention
      study.

      OBJECTIVES:

      • Primary goal of the research is to determine how the MI practice intervention will
      influences on the recovery of neuromuscular and locomotor function following TKA.

      Specific goals of the research are as follows:

        -  To examine effects of MI practice intervention to other measured parameters as follows:

             1. maximal isometric strength of knee extensors,

             2. maximal voluntary activation level

             3. spatio-temporal gait parameters during different gait velocities under single- and
                dual-task conditions,

             4. contractile muscle parameters,

             5. electromechanical efficiency index,

             6. self-reported measure of knee function (OKS and LEFS),

             7. and pain level assessed by Visual Analogue Scale (VAS).

                HYPOTHESIS:

                The main hypothesis of this dissertation is that the group, which will perform
                motor imagery practice intervention will have fewer decline in motor functions
                following TKA surgery.

                H1: Motor imagery (MI) leads to lower functional decline at one-month period after
                surgery as compared to control group (CON).

                H1.1: Patients in MI intervention group have fewer decline in maximal isometric
                knee extensors strength.

                H1.2: Patients in MIp intervention group have fewer decline in spatio-temporal gait
                parameters during different gait velocities under single- and dual-task conditions.

                H1.3: Patients in MI intervention group have fewer decline in voluntary muscle
                activation level.

                H1.4: Patients in MI intervention group will not experience significantly greater
                decline in contractile muscle parameters as compared to CON group.

                H1.5: Patients in MI intervention group have fewer decline in electromechanical
                efficiency index.

                H1.6: Patients in MI intervention group have better self-reported knee function
                assessed by self-reported questionnaires.

                H1.7: Patients in MI intervention group have fewer pain level assessed by VAS.

                  1. Methods

                Participants:

                N = 26 (man/woman) of which:

             1. Symptomatic population / n = 26; have already determined date for TKA surgery

                Participants will be recruited from Valdoltra orthopedic hospital (Ankaran,
                Slovenia).

                Inclusion criteria: scheduled for unilateral TKA secondary to osteoarthritis; age
                from 50 to 80 years old; participants were not engaged in preoperative treatments;

                Exclusion criteria: participants who had a previous history of TKA on the same side
                as the surgery; body mass index of 40 kg/m2 or higher; bilateral TKA's; patients
                with a history of any neurological disorder including Cerebral Vascular Attack,
                Multiple Sclerosis, or Parkinson's disease; patients with Rheumatoid Arthritis or
                active cancer; thrombose; bleeding after surgery; previously participation in
                imagery training.

                Sample Size:

                Isometric knee extension strength of the surgical leg was defined as the primary
                outcome variable for the power analysis. The sample size was calculated based on
                Hopkins recommendations (W. G. Hopkins, 2006) using online available spreadsheet
                (http://sportsci.org/resource/stats/index.html). Raw mean difference in change
                (RDC) was calculated based on pilot study of my own (RDC = 48,51 Nm) (unpublished
                data). Further, minimal clinically important change (MCIC) (MCIC = 21,89 Nm) (van
                der Roer, Ostelo, Bekkering, van Tulder, & de Vet, 2006) was calculated based on
                standard error of measurement (SEM) (SEM = 7,9 Nm) from study of Lienhard (Lienhard
                et al., 2013) that assessed reliability of isometric knee extensor strength of TKA
                patients. Given that in clinical practice the drop out of subjects is common
                because of many reasons (aging process, comorbidities, post-surgery complications),
                we adjusted originally calculated sample size by following formula: N1 = n/(1-d)
                (Sakpal, 2010) where N1 is adjusted sample size, n is the sample size required as
                per proposed formula ( N = 7 per group) and d is the drop-out rate (d = 0,25). This
                resulted in a target sample size of 10 in each of two groups (Mip and control). The
                recruitment of the patients will continue until the target sample size is achieved.

                2. Procedure

                - Ethical permission (already approved) - Ethics Committee of Valdoltra orthopedic
                hospital.

                - Measurement assessment participants PRE-surgery (one day before surgery on
                average)

                - MI practice intervention

                - Measurement assessment participants POST-surgery 1 (one month after surgery on
                average)

                - Measurement assessment participants POST-surgery 2 (one year after surgery on
                average)

                The patients will be randomized into two groups: the experimental MI practice group
                (MIp) and control group (CON), which will have common in patient and home-based
                physical therapy only. Subjects in both groups will receive one daily continuous
                passive motion (CPM) session (Kinetec Performa), beginning on the second day after
                TKA (immediately after intensive care) until discharge (5 to 7 days). Nurses will
                install the CPM device, by the standardized procedure. Identical installations will
                be performed for both groups: subjects laying supine in their bed, and the CPM
                device will be placed under the operated leg with the knee extended. For stability,
                one strap will surround the subject's thigh, another strap surrounds the subject's
                lower leg, and the apparatus will be prevented from sliding down by the edge of the
                bed. The CPM will be used for 45 minutes continuously, including a 5-minute warm-up
                period.

                Patients included in MI group will have intervention based on motor imagery
                technique with beginning immediately after intensive care. In detailed, they will
                be advised to imagine maximal voluntary isometric contractions (MViC). MViC imagery
                practice will be progressive. Thus, it will be performed in two sets of 25
                repetitions with 2 minutes of inter-sets rest period, with 10 additional trials in
                week three and four. Each MViC repetition should be sustained for 5 seconds,
                followed by 5 seconds of inter-repetition rest periods. Additionally, after every
                five contractions, participants will have a 20 seconds of rest in order to minimize
                the onset of mental fatigue (Rozand, Lebon, Stapley, Papaxanthis, & Lepers, 2016).
                Following 5 days of MIp the participants were advised to take a break from MIp for
                two days in a raw.

                After release from the hospital participants from MIp group will be supplied with
                audio description of exercise they need to perform in order to better concentrate
                to MIp task, rather than programme variables itself. Additionally, after release
                from hospital both groups will be supplied with a physical exercise program that
                they need to perform in home-based environment (like that one they will have in the
                hospital). In general, exercise programme considered active and passive knee
                flexion, abduction and adduction of the hip in the horizontal plane. Knee extensor
                muscle strengthening exercises such as unilateral knee extension with resistance of
                healthy leg, bilateral sit up from the higher chair/the high was adjusted by the
                pillow, unilateral weight bearing eccentric contraction supported with crutches
                etc. Next, functional exercises with weight bearing were adviced with attention of
                transferring the preasure (personal weight) on operated leg as much as possible.

                Each participant will be called by the phone every day in order to monitor their
                adherence to the prescribed exercise programme (lower than 80% of adherence will be
                excluded from the post analysis).

                Given that reported placebo effect in psychological outcomes of exercise training
                is small (ES = 0,20) (Lindheimer, O'Connor, & Dishman, 2015), to control it and
                additional socio-psychological influence of MIp instructor on the MIp outcomes, we
                will ensure the same conditions for the other group and spend the same amount of
                time with them (approximately 15 minutes per day) with each patient (verbal
                communication on site/in hospital or by telephone call/after discharge) regardless
                of his randomization to the group.

                Measurement assessments:

                Measurement assessment will be conducted in period before TKA (BT), and 1 month
                after the surgery.We will evaluate:

                I. Cognitive assessment:

                - Montreal Cognitive Assessment (MoCA): cognitive screening tool for Mild Cognitive
                Impairment

                II. Anthropometry:

                - Body weight and height (Stable stadiometer Seca, Birmingham, UK) and body
                composition (Bio-impedance system MALTRON BF-906).

                III. Functional status:

                - flexibility of knee joint (flexion and extension ROM) - assessed by manual
                goniometer

                - agility and dynamic balance (Timed "Up & Go" Test)

                - Sit to stand (30 seconds)

                - spatio-temporal gait parameters (STGP) during different gait velocities will be
                measured by OPTOGAIT system (Microgate, Bolzano, Italy) under single- and dual-task
                conditions.

                  -  Hand grip strength along with both the knee extensors and flexors muscles
                     maximal voluntary isometric strength (MViC) (isometric dynamometer S2P)

                  -  Self - reported functional assessment (OKS and LEFS questionnaires)

                IV. Muscle function:

                  -  contractile muscle parameters (Tensiomyography)

                  -  electromechanical efficiency index (Tensiomyography and M-wave module)

                  -  Voluntary activation level (using double interpolated twitch technique) V.
                     Pain level - Visual analogue scale (VAS)
    

Intervention name(s): Motor imagery practice
Intervention type(s): Other
Intervention description(s): In detail, they were advised to imagine maximal voluntary isometric contractions (MViC). MViC imagery practice was planned in a progressive manner. Thus, it was performed in two sets of 25 repetitions with 2 minutes of inter-sets rest period, for two weeks, and 10 additional repetitions were added on week three and four, respectively. Each MViC repetition was sustained for 5 seconds, followed by 5 seconds of inter-repetition rest periods. Additionally, after every fifth contraction, participants had a 20 seconds of rest. Following 5 days of MI practice, the participants were advised to take a break from MI for two consecutive days. After hospital discharge, the participants in the MIp group were supplied with an audio description of the exercises to be performed.
Other intervention name(s): Routine physical therapy
Allocation: Randomized
Intervention model: Parallel Assignment
Intervention model description: This was a randomized, controlled, parallel-group intervention trial to evaluate the benefits of adding MI practice to CPT postoperative rehabilitation program. Eligible patients were randomly assigned to either an intervention group in which MI practice was combined with CPT (MIp), or to a control group which received CPT alone (CON).
Masking: Double (Participant, Care Provider)
Primary purpose: Supportive Care
Keywords: osteoarthritis; muscle voluntary activation; knee replacement; cognitive training; functional performance; randomized controlled trial