Abnormal and cumulative loading in knee osteoarthritis.

Area of Science:

• Biomechanics
• Orthopedics
• Kinesiology

Background:

• Knee osteoarthritis (OA) is characterized by abnormal joint mechanics.
• Current research often focuses on the knee adduction moment in OA gait.
• Emerging evidence highlights the role of kinematics, muscle activity, and other lower extremity joints.

Purpose of the Study:

• To review recent advancements in understanding knee OA mechanics.
• To provide a rationale for assessing total knee loading exposure during daily activities.

Main Methods:

• Literature review of recent studies on knee osteoarthritis biomechanics.
• Examination of abnormal loading parameters (e.g., knee adduction moment).
• Introduction of cumulative load as a measure of total loading exposure.

Main Results:

• Abnormal loading, including the knee adduction moment, is a key feature of knee OA.
• Knee kinematics, muscle activation, and other lower extremity joint mechanics significantly influence knee loading.
• Excessive and repetitive loading contribute to knee pathomechanics and articular cartilage damage.

Conclusions:

• Knee OA pathomechanics result from an interplay of abnormal and excessive/repetitive loading.
• Lower extremity joint mechanics and muscle activity modulate the knee loading environment.
• Integrating abnormal and total loading assessments is crucial for linking biomechanics to clinical outcomes in knee OA.