Patient activity after TKA depends on patient-specific parameters

Area of Science:

• Orthopedic surgery
• Biomedical engineering
• Physical therapy

Background:

• Patients undergoing total knee arthroplasty (TKA) anticipate enhanced mobility and activity levels.
• Quantitative and qualitative assessments of post-TKA activity are limited in existing literature.

Purpose of the Study:

• To quantitatively assess physical activity before and after TKA using accelerometry.
• To compare post-TKA activity levels with an age-matched control group.
• To evaluate the achievement of physical activity guidelines and identify influencing patient factors.

Main Methods:

• Activity was measured using accelerometers in 97 patients pre-TKA and 1 year post-TKA.
• Key metrics included total steps, moderate-to-vigorous activity (≥100 steps/min), and time spent in various positions.
• A control group of 39 individuals without lower-extremity disorders was included for comparison.

Main Results:

• A significant increase in daily steps (5278 to 6473) and moderate-to-vigorous steps (1150 to 1935) was observed post-TKA.
• Despite improvements, TKA patients exhibited considerably lower activity levels compared to controls.
• Only 16.5% of patients met the 10,000 steps/day guideline; BMI, sex, and comorbidities influenced outcomes.

Conclusions:

• TKA leads to increased walking and moderate-to-vigorous activity, but guideline adherence remains low.
• Patient factors such as BMI, sex, and comorbidities significantly impact post-TKA activity levels.
• Surgeons should manage patient expectations regarding activity levels after TKA, as they generally remain below those of healthy controls.