Total Knee Arthroplasty (TKA) Rehabilitation Protocol

Clinical Presentation

Patients undergoing TKA typically present with significant knee pain, limited range of motion (ROM), and functional limitations affecting activities of daily living (ADLs). Common symptoms include:

• Pain aggravated by weight-bearing and activity.
• Stiffness and decreased knee ROM, impacting gait and stair climbing.
• Joint swelling and effusion.
• Muscle weakness, particularly in the quadriceps and hamstrings.
• Altered gait patterns and compensatory movements.

Pre-operative assessment should include a thorough history, physical examination, and functional testing to establish baseline measurements and identify individual patient needs.

Rehabilitation Phases

Phase 1: Acute Phase (Post-op Days 1-2 Weeks)

Goals: Pain and edema control, achieve 0-90 degrees knee flexion, initiate quadriceps activation, independent transfers with assistive device.

• Interventions:
• Cryotherapy and compression to manage pain and swelling.
• Ankle pumps and calf muscle contractions to prevent DVT.
• Quadriceps sets (isometric contractions).
• Heel slides to promote knee flexion.
• Assisted knee extension exercises.
• Gait training with appropriate assistive device (walker or crutches).
• Patellar mobilizations to prevent adhesions.

Phase 2: Sub-Acute Phase (2-6 Weeks)

Goals: Improve ROM (0-110 degrees), increase strength, improve balance and proprioception, wean from assistive device.

• Interventions:
• Progressive ROM exercises, including stretching and joint mobilization.
• Closed-chain exercises (partial squats, leg press).
• Open-chain exercises (knee extensions with resistance band, hamstring curls).
• Balance training exercises (single leg stance, weight shifting).
• Proprioceptive exercises (BOSU ball activities).
• Soft tissue mobilization to address scar tissue.

Phase 3: Strengthening Phase (6-12 Weeks)

Goals: Maximize strength and endurance, improve functional mobility, prepare for return to ADLs and recreational activities.

• Interventions:
• Progressive resistance training with weights or resistance bands.
• Advanced closed-chain exercises (full squats, lunges).
• Plyometric exercises (step-ups, box jumps).
• Agility drills (cone drills, shuttle runs).
• Functional training (stair climbing, walking on uneven surfaces).
• Cardiovascular conditioning (stationary bike, elliptical).

Specific Exercise Examples

1. Ankle Pumps: Dorsiflex and plantarflex the ankle repeatedly to improve circulation.
2. Quadriceps Sets: Tighten the quadriceps muscle by pushing the back of the knee into the floor and hold for 5 seconds.
3. Heel Slides: Slide the heel along the bed to bend and straighten the knee.
4. Straight Leg Raises (SLR): With the knee straight, lift the leg off the bed, keeping the quadriceps muscle engaged.
5. Short Arc Quads: With a bolster under the knee, extend the lower leg towards the ceiling.
6. Hamstring Curls: Bend the knee, bringing the heel towards the buttocks.
7. Partial Squats: Stand with feet shoulder-width apart and gently lower the body, keeping the back straight.
8. Leg Press: Use a leg press machine to strengthen the quadriceps, hamstrings, and gluteal muscles.
9. Step-Ups: Step onto a low platform or step, alternating legs.
10. Balance Training: Stand on one leg for increasing periods of time, progressing to more challenging surfaces.
11. Cycling: Use a stationary bike to improve cardiovascular fitness and knee ROM.
12. Lunges: Take a large step forward and lower the back knee towards the ground, keeping the front knee aligned over the ankle.

Evidence-Based Return to Function Criteria

Return to function criteria should be individualized based on patient goals and progress. General guidelines include:

• Pain: Controlled with minimal medication.
• Range of Motion: At least 0-120 degrees knee flexion.
• Strength: Symmetrical strength (within 80%) compared to the unaffected limb. Measured with handheld dynamometry or isokinetic testing.
• Functional Testing:
• Ability to perform ADLs without significant pain or difficulty.
• Successful completion of stair climbing.
• Good balance and proprioception.
• Satisfactory gait pattern (assessed visually and potentially with gait analysis).
• Patient Reported Outcome Measures (PROMs): Improved scores on questionnaires like the Knee Injury and Osteoarthritis Outcome Score (KOOS) or Oxford Knee Score.

Progression through the rehabilitation phases should be guided by objective measures and patient tolerance. Regular communication between the physical therapist, surgeon, and patient is crucial for optimal outcomes. This protocol provides a general framework and should be adapted based on individual patient needs and circumstances.