Is it bad if your knees go inward? Understanding Knock Knees (Genu Valgum)

October 1, 2025 •

4 min read

Approximately 99% of young children with knees that go inward, a condition known as genu valgum or knock knees, will see the condition correct itself by age seven. While often part of normal development, persistent or adult-onset cases require attention to understand: is it bad if your knees go inward?

Quick Summary

Knees that turn inward, or genu valgum, can result from natural growth or underlying conditions like injury or weak hips. Persistent cases can cause joint pain, altered gait, and increased injury risk. Treatment involves exercises, physical therapy, and, in severe situations, surgical intervention.

Key Points

Normal Development vs. Persistent Condition: Knees that go inward are a normal developmental stage in many children, but persistent or adult-onset cases, known as genu valgum, may require medical attention.
Underlying Causes: Reasons for knock knees include genetics, muscle imbalances (especially weak glutes), obesity, and prior injury or disease like rickets or arthritis.
Chain Reaction of Issues: Poor knee alignment affects the entire kinetic chain, potentially causing pain and stress in the knees, hips, and ankles, and altering gait.
Increased Injury Risk: Athletes exhibiting inward knee collapse during activity (dynamic knee valgus) may face a higher risk of ACL tears and other knee injuries.
Treatment Options: Conservative treatments include physical therapy to strengthen supporting muscles and improve mobility. Severe cases may require orthotics, bracing, or surgical correction.
Consult a Professional: For persistent pain, altered gait, or instability, consulting a physical therapist or orthopedic specialist is crucial for proper diagnosis and a personalized treatment plan.

Understanding Knee Valgus (Knock Knees)

Knee valgus, or genu valgum, is a condition where the knees angle inward and may touch when standing with ankles apart. This differs from normal leg alignment where a straight line goes from the hip, through the knee, to the ankle. While inward angling is common during childhood growth, persistent genu valgum can place excessive force on the outer knee, leading to pain and potential joint damage over time.

The Causes Behind Inward-Tilting Knees

The reasons for knee valgus vary and include both typical developmental stages and more serious medical conditions.

Developmental and Acquired Causes

Normal Childhood Growth: Toddlers and young children often have knock knees as a normal phase of development, which typically resolves by age 7.
Genetics: A tendency for genu valgum can be inherited.
Weakness in Supporting Muscles: Weak hip muscles, particularly the glutes, can cause hips to rotate inward, leading to the knees caving in during movement.
Tightness and Mobility Issues: Limited ankle mobility or tightness in the hip adductors and IT band can contribute to knee valgus.
Obesity: Extra weight puts stress on joints, potentially worsening or contributing to knock knees.

Underlying Medical Conditions

Rickets: A deficiency in vitamin D and calcium, causing softened bones and improper development.
Skeletal Dysplasia or Metabolic Disorders: Certain bone growth disorders can cause misalignment.
Trauma or Injury: Leg or growth plate injuries in childhood can affect bone alignment.
Osteoarthritis and Arthritis: Pre-existing arthritis can worsen or lead to genu valgum.

Potential Health Risks: Is it Bad if Your Knees Go Inward?

While mild or temporary knock knees may not cause significant problems, pronounced or persistent misalignment can lead to several issues:

Joint Pain: Uneven weight distribution can cause pain in the knees, hips, and ankles.
Altered Gait and Instability: An abnormal walking pattern can develop, leading to discomfort and a feeling of instability in the knees.
Increased Risk of Injury: Individuals with knee valgus, especially during movement (dynamic knee valgus), may have a higher risk of ligamentous injuries like ACL tears.
Osteoarthritis: Abnormal joint loading can increase wear and tear on knee cartilage, potentially leading to premature arthritis.

A Chain Reaction Through the Body

Knee valgus affects the kinetic chain from feet to spine, potentially causing:

Internal Hip Rotation: This can stress the IT band and hip structures.
Excessive Foot Pronation: The feet may roll inward, stressing ankles and feet.
Compensatory Pain: The body's adjustments can lead to pain in hips, back, and other areas.

How to Address Knock Knees

Treatment depends on the cause and severity. Mild cases in children often resolve naturally. Other cases may require a combination of approaches.

Non-Surgical Treatments

Weight Management: Reducing excess weight can decrease stress on knee joints.
Physical Therapy: A physical therapist can create a program to strengthen weak muscles (like glutes) and improve ankle mobility.
Orthotics: Shoe inserts can help with foot and ankle imbalances.
Bracing: In children, a brace may guide bone development.

Physical Therapy Exercises for Strengthening

Exercises often target strengthening hip abductors and external rotators to improve knee control and alignment.

Clamshells: Strengthens the gluteus medius by lifting the top knee while lying on your side with knees bent.
Banded Squats: Using a resistance band above the knees while squatting helps train hips to resist inward collapse.
Hip Bridges: Lying on your back and lifting hips activates the gluteus maximus.
Side-Lying Hip Abduction: Lifting the top leg straight up targets hip abductors.
Single-Leg Balance: Improves stability and neuromuscular control.

Surgical Treatments

Surgery is typically for severe cases, those unresponsive to other treatments, or when an underlying issue needs correction.

Guided Growth Surgery: In children, a small metal plate can guide leg alignment.
Osteotomy: In adults, bone in the femur or tibia is cut and reshaped to correct alignment.

Valgus vs. Varus Knees: A Comparison


Feature	Valgus Knees (Knock Knees)	Varus Knees (Bowlegs)
Appearance	Knees angle inward, touching or nearly touching when feet are apart.	Knees angle outward, with a noticeable gap between the knees when feet are together.
Pressure Point	Increased pressure on the lateral (outer) side of the knee joint.	Increased pressure on the medial (inner) side of the knee joint.
Associated Condition	Can lead to lateral compartment osteoarthritis.	Can lead to medial compartment osteoarthritis.
Muscular Effects	Often linked to weak hip abductors and overactive adductors.	Can be associated with tightness in the IT band and lateral collateral ligament.
Pronation/Supination	Tends to cause excessive foot pronation (feet roll inward).	Often associated with excessive foot supination (feet roll outward).

Conclusion: When to Seek Medical Advice

While inward-tilting knees are common and often benign in young children, persistent or painful genu valgum in older individuals warrants evaluation by a healthcare professional, such as a physical therapist or orthopedic specialist. Early intervention can help prevent long-term complications like arthritis and reduce pain. The answer to is it bad if your knees go inward? depends on the individual case, but paying attention to symptoms and seeking expert guidance is always a wise step toward better joint health. Learn more about orthopedic conditions from the Hospital for Special Surgery.

Frequently Asked Questions

Yes, targeted exercises can help correct functional knee valgus by strengthening key muscles. Strengthening the hip abductors (like the gluteus medius) and improving ankle mobility can help stabilize the knee and reduce the inward collapse during movement.

Symptoms of knock knees can include visible inward angling of the knees, an altered or unsteady gait, knee or hip pain, reduced mobility, and a feeling of instability or buckling in the knees.

Yes, genetic factors can play a role in the development of knee valgus. Some individuals are naturally born with an anatomical structure that makes them more prone to the condition.

Yes, carrying excess body weight places additional strain and stress on the knees. This can contribute to or worsen genu valgum, as the increased load further compromises proper joint alignment.

No, most cases of knock knees in children are part of normal development and resolve on their own by around age seven. Medical intervention is generally only needed for persistent, severe, or painful cases.

An adult should see a doctor if they experience persistent knee or hip pain, joint instability, or a limp. These symptoms can indicate increased stress on the joints and potential long-term damage, such as arthritis.

Dynamic knee valgus refers to the inward collapse of the knee during movement, such as while squatting, landing from a jump, or running. It is often a result of poor muscle control, particularly in the hips, and is associated with an increased risk of injury.