The ACT-ON: A Geriatric 5-Ms-Guided Physical Therapy Intervention for Knee Osteo-Arthritis in Older Adults.

Knee osteoarthritis (OA) is a leading cause of disability in midlife and older adulthood, representing a quintessential geriatric condition characterized by multi-complexity. Its management extends beyond impaired mobility to significantly impact mentation, medication use, and overall quality of life. While he 21st century is characterized by a profound global demographic shift towards an older population. While a testament to public health advances, this aging trend precipitates a surge in the prevalence of chronic, debilitating conditions. Among these, knee osteoarthritis (OA) stands as a leading cause of musculoskeletal pain, functional limitation, and diminished quality of life worldwide. The substantial and rising burden of knee OA, both globally and in regions like Saudi Arabia. The burden is not only clinical but also socioeconomic, contributing significantly to healthcare costs, caregiver strain, and loss of independence. Underscores the urgent need for effective, person-centered care models that can address the complex needs of older adults. In response to this challenge, the geriatric community established the "5Ms" framework (encompassing What Matters, Medication, Mentation, Mobility, and Multi-complexity) to provide a holistic, evidence-based model for care. To operationalize this framework specifically for rehabilitation, the Academy of Geriatric Physical Therapy developed "Guiding Principles for Best Practices". For physical therapists, the 5Ms framework is instrumental in delivering this holistic care. While Mobility is a primary focus, effective intervention requires integrating all components: addressing Mentation (e.g., using exercise to manage depression), reviewing Medications that may impact balance or pain, and navigating the patient's Multi - complexity. Crucially, all care is centered on "What Matters Most" to the patient, ensuring interventions are meaningful and lead to improved outcomes. the Geriatric 5Ms framework provides a vital, person-centered structure for holistic geriatric care, aligning interventions with patient goals while navigating medical complexities. a clear gap exists in its systematic application within physical therapy (PT). Standard PT often prioritizes predominantly on the "Mobility" domain, potentially overlooking the critical interplay of other factors that influence patient outcomes. Therefore, the significance of this study lies in its effort to bridge this gap by translating the comprehensive 5Ms model into an actionable, PT-specific protocol the "Act on Program" thereby testing a more integrated and patient-centered approach to a pervasive health problem. This randomized controlled trial will test this more integrated approach to a pervasive health problem, addressing a critical evidence gap, as no prior RCTs have tested the application of the 5Ms framework in physical therapy for knee OA.

Details of all outcome measures (Stay Independent Brochure, Icon-FES, TUG, 2MWT, 5xSTS, ASES-8, PSFS, and MedRisk) were provided, including the purpose of each scale and the domain it assesses.

The outcome measures used in this study include both performance-based and patient-reported tools, each assessing a specific domain relevant to older adults with knee osteoarthritis. The Stay Independent Brochure is used as an educational and fall-risk awareness tool to identify fall-related concerns. The Iconographical Falls Efficacy Scale (Icon-FES) assesses concern about falling during daily activities. Functional mobility and physical performance are evaluated using the Timed Up and Go (TUG), 2-Minute Walk Test (2MWT), and Five-Times Sit-to-Stand Test (5xSTS), which measure balance, walking endurance, and lower-limb strength, respectively. The Arthritis Self-Efficacy Scale-8 (ASES-8) measures confidence in managing arthritis-related symptoms. The Patient-Specific Functional Scale (PSFS) captures patient-identified functional limitations and goals, while the MedRisk questionnaire assesses patient satisfaction with physical therapy services.

These measures assess distinct, non-overlapping constructs aligned with the Geriatric 5Ms framework and cannot be adequately captured by one or two tools alone. All instruments are brief, validated for older adults, and feasible to administer within a one-hour assessment session with rest breaks.

Data related to the Mind domain will be obtained through brief cognitive screening using the Mini-Cog and observation of participant performance during dual-task activities. Mobility data will be collected using standardized gait, balance, and fall-prevention exercises and functional performance tests administered by the physical therapist, including the Five-Times Sit-to-Stand Test (5xSTS), 2-Minute Walk Test (2MWT), and KOS-ADLS. Information regarding Medications will be obtained through participant self-report and review of current medication use, with attention to potential mobility-related side effects; any concerns will be referred to the treating physician when appropriate. Multi-complexity data will be gathered through review of medical history and observation of participant response to exercise, allowing the intervention to be adapted to comorbid conditions. Matters Most data will be obtained through structured patient interviews and goal-setting using participant-identified functional priorities (PSFS), with the Arthritis Self-Efficacy Scale-8 (ASES-8) used to assess confidence in managing arthritis-related goals.

The intervention of 5MS during the session was explain in the procedure section of the form. About utilization of the 5 domains in study from side of physical therapy (Mind will be addressed through brief cognitive screening at baseline and by monitoring performance during simple dual-task activities to support safety. Therapeutic interventions must be tailored to the patient's cognitive capacity, with environmental structuring and guided strategies provided for those with impaired cognition to ensure safe task completion.

Mobility will be the primary focus of each session and will include individualized gait training, balance exercises, strengthening, and fall-prevention strategies appropriate for knee osteoarthritis. The exercise program must be explicitly progressive and systematically address strength, range of motion (ROM), and functional mobility. This requires regular screening and examination of gait, balance, transfer ability, and endurance to quantify improvement and guide intervention. A combined model integrating high-intensity resistance training with neuromuscular exercises is recommended to synergistically target muscle capacity and dynamic joint control. High-intensity training is a viable and effective option for a specific patient subset: those with mild-to-moderate disease (Kellgren-Lawrence grade ≤ III), a BMI < 30, and no severe cardiovascular comorbidities. Such progressive regimens must be initiated under supervision before transitioning to home training.

Medications will be considered through participant self-report of current medication use and any perceived mobility-related side effects, solely to inform exercise monitoring and safety; no medication advice will be provided, and concerns will be referred to the treating physician.: Physical therapists must systematically monitor medication-related effects through weekly check-ins, specifically asking: "Have there been any changes to your medications? How is the pain medication working for you?" This includes conducting a structured interview to document all prescription medications, over-the-counter drugs (especially NSAIDs), and supplements. Particular attention should be paid to analgesics (type, dosage, frequency, and effectiveness), polypharmacy (flagging patients taking ≥5 medications), and high-risk medications (screening for long-term/high-dose NSAID use in patients with comorbidities). Poor pain control or adverse effects should be reported to the referring physician.

Multi-complexity will be addressed by adapting exercises based on comorbidities, pain, fatigue, and functional tolerance. Physical therapists must systematically account for multi-complexity by documenting all comorbidities using a tailored Comorbidity Checklist and conducting brief nutritional screening. This documentation serves not for exclusion but for customizing exercise prescriptions, with continual monitoring of vital signs and specific inquiries about condition management (e.g., "How is your blood sugar control?"). Clinical reasoning focuses on how each condition modifies exercise priorities and risks, such as emphasizing balance training for diabetic neuropathy or adjusting intensity for cardiovascular limitations

Matters Most will guide shared goal setting, with therapy tailored to participant-identified functional priorities. The exercise program must be directly related to the patient's most valued life activities. This is established through a semi-structured interview using the Patient-Specific Functional Scale (PSFS), where the clinician asks: "What three activities are most important to you but are difficult or impossible to do because of your knee problem?", creating patient-centered goals for the entire intervention. These goals should be reviewed at the start of each session to track progress toward what matters most to the patient.

The research team acknowledges the concern regarding the number of outcome measures and the estimated completion time. All selected questionnaires and performance-based tests are brief, validated instruments commonly used in older adult and knee osteoarthritis research. The total assessment time has been carefully piloted and remains within the proposed one-hour session, with scheduled rest breaks and flexibility to pause or reschedule testing if fatigue occurs. Questionnaires will be administered in an assisted, interviewer-led format to reduce participant burden and improve completion efficiency. In addition, outcome measures are administered only at two time points (baseline and post-intervention). To further ensure feasibility, primary outcome measures will be prioritized, and secondary measures will be omitted if participant tolerance is exceeded, without compromising participant safety or study integrity.

A fully scripted session-by-session intervention manual will not be used. Instead, both groups will receive standardized, guideline-based intervention protocols with clearly defined core components, progression principles, safety parameters, and allowable individualization. This approach reflects real-world physical therapy practice while ensuring consistency and treatment fidelity across participants.

Control group (Standard impairment-based physical therapy):

Participants will receive a structured impairment-based physical therapy program aligned with current clinical practice guidelines for knee osteoarthritis. Core components will include lower-limb strengthening (quadriceps, hamstrings, hip abductors), aerobic conditioning (e.g., walking or stationary cycling), flexibility, balance, range of motion, gait training, and standardized biomedical education addressing osteoarthritis self-management (weight management, joint protection, knee anatomy and biomechanics, and tissue healing timelines). Exercise intensity and progression will follow established principles of progressive overload and American College of Sports Medicine (ACSM) guidelines, progressing from low to moderate intensity based on participant tolerance and safety.

Experimental group (5Ms-guided physical therapy):

Participants in the experimental group will receive all components of the standard physical therapy program. In addition, treatment will be systematically guided by the Geriatric 5Ms framework (What Matters Most, Medications, Mind, Mobility, and Multi-complexity).

What Matters Most: Shared goal setting using the Patient-Specific Functional Scale to align exercises with patient-prioritized activities.

Mobility: Emphasis on individualized gait, balance, strengthening, functional training, and fall-prevention strategies, with progressive exercise prescription.

Mind: Baseline cognitive screening and ongoing monitoring during therapy activities to ensure safety and appropriate task demands.

Medications: Weekly monitoring of self-reported medication use and side effects solely to inform exercise safety, with referral to physicians when concerns arise.

Multi-complexity: Adaptation of exercise prescription based on comorbidities, fatigue, pain, and functional tolerance, with ongoing clinical monitoring.

Intervention delivery and fidelity:

All interventions will be delivered by licensed physical therapists following predefined treatment domains, progression criteria, and safety rules. Individualization will be permitted within these boundaries to account for patient tolerance and clinical presentation, without altering the core structure of the intervention. This approach ensures feasibility, safety, and consistency across the 16 sessions for both groups.