When standing or engaging in movements like squatting, some individuals notice their knees tending to collapse inward. This common observation is often referred to as “knee valgus” or “knock knees.” While sometimes a natural variation in body alignment, this inward movement can also signal underlying issues that might affect joint health over time.
Understanding Knee Valgus Collapse
Knee valgus collapse is when the knees move towards each other, sometimes appearing to touch or “knock,” disrupting their natural alignment with the hips and ankles. This inward shift can occur during weight-bearing activities, from simple standing to dynamic movements like squatting, running, or jumping. This position places increased stress on the medial, or inner, side of the knee joint. This elevated stress can strain the ligaments and cartilage, potentially contributing to discomfort or an increased risk of injury over time.
Primary Muscular and Biomechanical Causes
Several factors contribute to knees caving inward, with muscle imbalances and foot mechanics being common culprits. Weakness in the gluteal muscles can lead to the hip moving into adduction (inward) and internal rotation, causing the knee to collapse inward. These gluteal muscles are important for stabilizing the hip and maintaining proper lower limb alignment. Tightness in the adductor muscles can also pull the knee inward and contribute to this alignment issue.
Foot mechanics also play a role, with overpronation being a significant contributor. Overpronation occurs when the foot rolls excessively inward and the arch flattens during weight bearing. This excessive inward rolling of the foot can create a chain reaction, causing the ankle to rotate inward and leading to the knee moving into a valgus position. Inadequate ankle dorsiflexion can also force the foot to overpronate as a compensatory mechanism, further contributing to knee valgus.
Other Potential Underlying Conditions
Beyond muscular imbalances and foot mechanics, other underlying conditions can contribute to knee valgus. Structural issues, such as genu valgum, is a skeletal alignment where the knees naturally angle inward even when standing with straightened legs. While a mild degree of genu valgum is normal in young children and often resolves by age seven, it can persist or develop later in life due to various factors including genetic predisposition, bone development disorders like rickets, or previous injuries.
Previous injuries to the knee or hip can also predispose an individual to knee valgus by altering joint mechanics and stability. Ligamentous laxity can result from congenital factors or trauma, leading to increased joint flexibility and potentially contributing to knee instability and valgus. Early-stage arthritis can also affect the structural integrity and alignment of the knee joint.
When to Seek Professional Evaluation
If you experience persistent pain in your knees, hips, or ankles that does not improve with rest or self-care, a medical assessment is advisable. Instability, a feeling that your knee might give out, or a sudden onset of knee caving without a clear cause also warrants professional attention.
Worsening symptoms over time, or if the condition begins to significantly impact your daily activities such as walking, standing, or exercising, are indications to consult a healthcare professional. A doctor or physical therapist can provide an accurate diagnosis, differentiate between functional and structural causes, and recommend an appropriate course of action. Self-diagnosis should not replace a comprehensive medical evaluation.
General Strategies for Improvement
Addressing knee valgus often involves a multi-faceted approach focused on improving strength, flexibility, and movement patterns. Strengthening the gluteal muscles and hip abductors is often emphasized to improve hip stability and control knee alignment. Incorporating exercises that target core stabilizers can also enhance overall trunk and pelvic control, which indirectly supports proper lower limb mechanics.
Stretching tight muscles, such as the hip adductors, can help restore a balanced range of motion around the hip and ankle joints. Improving overall movement patterns through conscious awareness and practice during activities like squatting or walking can help retrain the body to maintain better alignment. Considering appropriate footwear that provides arch support or using orthotic inserts can also help manage foot overpronation, thereby improving the kinetic chain alignment from the ground up. A healthcare professional can provide a tailored exercise program and guidance specific to individual needs.