Gait Analysis Study Comparing Unicompartmental vs. Total Knee Arthroplasty: Differences in Knee Kinematics

Area of Science:

• Orthopedic Surgery
• Biomechanics
• Gait Analysis

Background:

• Total knee arthroplasty (TKA) effectively treats knee osteoarthritis but may yield suboptimal functional outcomes.
• Unicompartmental knee arthroplasty (UKA) offers better functional recovery but has lower long-term implant survival.
• Personalized TKA approaches aim to enhance kinematic restoration and patient satisfaction.

Purpose of the Study:

• To compare knee kinematics between patients undergoing personalized TKA, medial UKA, and healthy controls.
• To investigate gait differences and knee motion during walking in these patient groups.

Main Methods:

• Retrospective cohort study involving 9 patients each for robotic-assisted personalized TKA, medial UKA, and 9 healthy controls.
• Gait analysis performed using a markerless instrumented treadmill (WalkerView™).
• Statistical analysis using one-way ANOVA and Tukey's post-hoc test to compare kinematic data.

Main Results:

• UKA patients demonstrated a stiffer knee during stance compared to TKA and controls.
• Knee range of motion during stance was significantly lower in UKA (6.3°) versus TKA (13.6°, p=0.045) and controls (16.6°, p=0.02).
• Lower limb loading response showed reduced knee flexion in UKA (10.2°) compared to TKA (19.4°, p=0.049) and controls (19.6°, p=0.004).

Conclusions:

• Unicompartmental knee arthroplasty patients exhibit reduced knee flexion during early stance.
• Observed gait differences may stem from surgical technique, implant design, or patient factors.
• Findings require cautious interpretation due to potential selection bias and warrant larger prospective studies for confirmation.