Valgus and Varus Knee: Causes, Effects and Treatment

To learn more, consult the guide on Patellar Tendinopathy: when jumper’s knee stops sport. To learn more, consult the guide on Runner’s Knee Pain: how to prevent and treat patellofemoral pain syndrome with the return of spring running. To learn more, consult the guide on Knee Cartilage Injury: Treatment.

The knee, a complex joint fundamental for ambulation and maintaining an upright posture, is subject to various biomechanical alterations that can compromise its function and long-term health. Among these, angular deformities in the frontal plane, known as genu valgum and genu varum, represent common conditions that warrant in-depth analysis. This article aims to explore the causes, symptoms, conservative treatment strategies – with a focus on corrective exercises – and indications for surgical intervention, offering a comprehensive overview to better understand and manage **genu valgum and genu varum**.

Table of Contents

• Knee Anatomy and Biomechanics
• Genu Valgum (Knock-Knee)
• Genu Varum (Bowleg)
• Conservative Treatment: Physiotherapy
• Prevention
• Surgical Treatment: When is it Necessary
• Frequently Asked Questions (FAQ)
• Conclusion
• Frequently Asked Questions
• Resources
• Sources and Scientific References

Knee Anatomy and Biomechanics

Knee anatomy and biomechanics refers to the structural components and movement patterns of the knee joint, located between the femur and tibia, which can present as inward or outward deviations. The knee is the largest joint in the human body, formed by the distal end of the femur, the proximal end of the tibia, and the patella. It is a modified hinge joint that allows flexion and extension movements, with a component of internal and external rotation when the knee is flexed. Its stability is ensured by a complex network of ligaments (cruciate and collateral), menisci (medial and lateral), and muscles (quadriceps, hamstrings, gastrocnemius).

For a complete overview, see the comprehensive guide to knee pain.

Under conditions of physiological alignment, the mechanical axis of the lower limb, which connects the center of the femoral head to the center of the ankle, should pass through the center of the knee. Any deviation from this alignment can lead to an abnormal distribution of joint loads, predisposing to cartilage wear, pain, and instability.

Genu Valgum (Knock-Knee)

Definition and Characteristics

Genu valgum, commonly known as “knock-knee” or “X-shaped knee,” is an angular deformity in which the knees tend to touch or come excessively close together when the feet are separated. In this condition, the mechanical axis of the lower limb deviates laterally from the center of the knee, placing greater load on the lateral compartment of the joint and straining the medial structures.

Causes

The causes of genu valgum can be multiple and vary based on the age of onset and the severity of the condition.

Physiological and Developmental Causes

• Childhood development: A mild genu valgum is often physiological in children between 2 and 6 years of age, resolving spontaneously in most cases with growth. This is due to normal skeletal and muscular maturation.

Pathological Causes

• Muscular imbalances: Weakness of hip abductor muscles (glutes), muscles of the medial thigh compartment and foot, or excessive tension of hip adductor muscles and lateral thigh muscles.
• Postural problems: Flat feet (excessive pronation), internal femoral rotation, pelvic anteversion. These alterations can affect the alignment of the entire kinetic chain.
• Trauma: Malunited fractures or growth plate (epiphyseal) injuries in pediatric age can alter bone growth.
• Metabolic or systemic diseases: Rickets, osteomalacia, skeletal dysplasias, chronic kidney diseases can affect bone mineralization and growth.
• Arthritis: Rheumatoid arthritis or osteoarthritis can lead to asymmetric cartilage deterioration, causing progressive deformity.
• Obesity: Excessive body weight increases stress on the joints, contributing to the development or worsening of valgus.
• Family history/Genetics: A genetic predisposition exists in some cases.

Symptoms and Complications

Symptoms of genu valgum can range from mild to severe and tend to worsen with age and physical activity.

• Pain: Often localized to the lateral compartment of the knee due to excessive load, or to the medial compartment due to ligament tension. It can radiate to the hip or ankle.
• Instability: Feeling of the knee giving way, especially during walking or running.
• Difficulty walking: Altered gait, with knees rubbing or bumping together.
• Stiffness: Limited knee movement, especially after periods of inactivity.
• Cartilage wear: In the long term, abnormal loading on the lateral compartment can lead to early osteoarthritis.
• Patellar problems: Patellofemoral pain syndrome, due to altered patellar tracking.
• Secondary muscular imbalances: Further weakening or hypertonicity of specific muscle groups.

Diagnosis

The diagnosis of genu valgum begins with a thorough medical history and physical examination by your doctor or physical therapist.

• Medical history: Collection of information on family history, previous trauma, physical activity, symptoms, and their evolution.
• Physical examination: Assessment of lower limb alignment in standing position and during walking. The Q-angle (angle between the quadriceps and the patellar tendon) and the intermalleolar distance (distance between the medial malleoli when the knees are joined) are measured. Muscle strength, flexibility, joint stability, and the presence of pain on palpation are evaluated.
• Instrumental examinations:

• X-rays: Weight-bearing X-rays of the lower limbs (tele-radiography or full-length lower limb X-rays) are essential for measuring the valgus angle and assessing mechanical alignment.

• Magnetic Resonance Imaging (MRI): Can be useful for assessing the condition of soft tissues (menisci, ligaments, cartilage) and identifying any associated damage.

• CT scan: Rarely necessary, but can provide more precise details on bone structure in complex cases.

Genu Varum (Bowleg)

Definition and Characteristics

Genu varum, known as “bowleg” or “O-shaped legs,” is an angular deformity in which the knees are separated when the feet are joined. The mechanical axis of the lower limb deviates medially from the center of the knee, causing excessive load on the medial compartment of the joint and straining the lateral structures.

Causes

For genu varum, too, the causes can be diverse:

Physiological and Developmental Causes

• Childhood development: A mild genu varum is often physiological in newborns and young children (up to 2 years old), due to fetal position and normal bone growth. It generally resolves spontaneously.

Pathological Causes

• Muscular imbalances: Weakness of hip adductor muscles and muscles of the lateral thigh compartment, or excessive tension of hip abductor muscles and medial thigh muscles.
• Postural problems: High arches (excessive supination), external femoral rotation, pelvic retroversion.
• Trauma: Malunited fractures or growth plate injuries in pediatric age.
• Metabolic or systemic diseases: Rickets, Blount’s disease (a growth disorder affecting the tibia), osteomalacia, skeletal dysplasias.
• Arthritis: Osteoarthritis, particularly of the medial compartment, is a common cause of progressive varus in adults.
• Obesity: As with valgus, excessive body weight can worsen the condition.
• Family history/Genetics: Genetic predisposition.

Symptoms and Complications

Symptoms of genu varum are similar to those of genu valgum, but with different localizations:

• Pain: Often localized to the medial compartment of the knee due to excessive load, or to the lateral compartment due to ligament tension.
• Instability: Feeling of the knee giving way.
• Difficulty walking: Altered gait, with legs appearing “bowed.”
• Stiffness: Limited movement.
• Cartilage wear: In the long term, abnormal loading on the medial compartment can lead to early osteoarthritis.
• Patellar problems: Altered patellar tracking.
• Secondary muscular imbalances: Further weakening or hypertonicity of specific muscle groups.

Diagnosis

The diagnosis of genu varum follows a similar path to that of genu valgum.

• Medical history and Physical examination: Assessment of alignment, measurement of the intercondylar distance (distance between the medial femoral condyles when the feet are joined), evaluation of muscle strength, flexibility, and stability.
• Instrumental examinations:

• X-rays: Weight-bearing tele-radiography of the lower limbs to measure the varus angle and mechanical alignment.

• Magnetic Resonance Imaging (MRI): To assess the condition of soft tissues and cartilage.

• CT scan: In selected cases.

Conservative Treatment: Physiotherapy

Conservative treatment, particularly physiotherapy, represents the first line of intervention for most cases of genu valgum and genu varum, especially when the deformity is mild or moderate and not associated with severe joint damage. The goal is to reduce pain, improve function, correct muscular imbalances, and, when possible, slow the progression of the deformity.

General Objectives

• Pain reduction: Through manual techniques, physical therapies, and activity modifications.
• Alignment improvement: By acting on posture, muscle strength, and flexibility.
• Muscle strengthening: Specific for weak muscles and stretching for tight muscles.
• Proprioceptive re-education: Improvement of balance and motor control.
• Patient education: Providing strategies for pain management and preventing worsening.

Physiotherapy Assessment

An experienced physical therapist will conduct a thorough assessment that includes:

• Postural analysis: Assessment of whole-body alignment, from head to toe, in static and dynamic positions.
• Gait assessment: Analysis of gait phases and identification of any compensations.
• Muscle tests: Assessment of strength and endurance of the main muscle groups involved (hip, thigh, leg, foot).
• Flexibility tests: Measurement of muscle length and joint mobility.
• Proprioceptive tests: Assessment of balance and coordination.
• Palpation: Identification of painful points or muscle tension.

Principles of Corrective Exercises

Corrective exercises are personalized based on the specific deformity and the patient’s individual characteristics. There is no single protocol, but some general principles guide the choice of exercises:

• Selective muscle strengthening: Strengthening muscles that contribute to restoring a more correct alignment.
• Muscle stretching: Releasing muscles that are excessively tight and contribute to the deformity.
• Postural re-education: Teaching the patient to maintain correct alignment during daily activities.
• Motor and proprioceptive control: Improving body awareness and the ability to control movements.

Specific Exercises (Examples of Types)

It is essential that these exercises are prescribed and supervised by a doctor or physical therapist, as incorrect technique could be ineffective or even harmful.

For Genu Valgum

The goal is to strengthen the hip abductor muscles (glutes), hip external rotators, and muscles of the medial thigh compartment, as well as to stretch the hip adductors and lateral thigh muscles.
Glute strengthening: Exercises such as clam shells, side-lying leg lifts, glute bridge, squats* with emphasis on glute activation and maintaining knee alignment. The use of an elastic band around the knees can help maintain glute activation and prevent valgus collapse.

• Foot and ankle muscle strengthening: Exercises to counteract flat feet, such as calf raises, picking up objects with toes.
• Hip adductor stretching: Adductor stretching in various positions.
• Proprioceptive exercises: Exercises on unstable surfaces (proprioceptive boards, proprioceptive cushions) to improve neuromuscular control of the knee and hip.
• Postural re-education: Awareness of lower limb alignment during walking, climbing/descending stairs, and other functional activities.

For Genu Varum

The goal is to strengthen the hip adductor muscles and muscles of the lateral thigh compartment, as well as to stretch the hip abductors and medial thigh muscles.
Hip adductor strengthening: Exercises such as adductor squeeze (squeezing a pillow between the knees), side lunges* with emphasis on adductor activation.

• Foot and ankle muscle strengthening: Exercises to counteract high arches or excessive supination.
• Hip abductor stretching: Stretching of the glutes and tensor fasciae latae.
• Proprioceptive exercises: Similar to those for valgus, but with a focus on varus alignment.
• Postural re-education: Awareness of alignment during daily activities.

Manual and Instrumental Therapies

In addition to exercises, the physical therapist may use:

• Manual therapies: Joint mobilizations, therapeutic massage to release muscle tension and improve mobility.
• Physical therapies: Ultrasound, laser therapy, electrotherapy for pain and inflammation management.
• Orthoses: Custom orthotics may be prescribed to correct foot posture and influence limb alignment. Specific knee braces can be used to stabilize the joint and reduce load on damaged compartments.

Postural Education and Lifestyle

The physical therapist will provide guidance on:

• Postural correction: Maintaining correct alignment during daily activities (standing, sitting, lifting weights).
• Weight management: Maintaining a healthy body weight to reduce stress on the knees.
• Footwear choice: Wearing appropriate shoes that support the arch and provide stability.
• Activity modification: Avoiding activities that aggravate pain or deformity, opting for low-impact exercises (swimming, cycling).

Prevention

Prevention of genu valgum and genu varum, especially in acquired forms, focuses on maintaining good body alignment and muscle strength.

• Weight control: Essential for reducing stress on the joints.
• Regular physical activity: Keeping leg and core muscles strong and flexible.
• Early correction of imbalances: Promptly addressing flat feet or high arches, or lower limb length discrepancies.
• Correct posture: Adopting ergonomic postures during work and daily activities.
• Regular pediatric visits: To monitor skeletal development in children and detect any anomalies early.

Surgical Treatment: When is it Necessary

Surgical intervention is considered when conservative treatment has been unsuccessful, when the deformity is severe, progressive, or causes significant pain and functional limitations that compromise quality of life.

Indications

• Persistent and debilitating pain: Despite an adequate course of physiotherapy and conservative therapies.
• Severe angular deformity: Radiographically measured, exceeding certain degrees considered pathological.
• Progression of the deformity: Especially in pediatric age or in the presence of diseases such as Blount’s disease.
• Significant joint damage: Evidence of advanced osteoarthritis in one compartment of the knee.
• Severe instability: That cannot be managed with muscle strengthening.

Types of Intervention

The choice of intervention depends on the patient’s age, the severity of the deformity, the underlying cause, and the presence of arthritis.

• Corrective osteotomy: It is the most common intervention to correct angular deformities. It involves cutting and realigning the bone (femur or tibia) to redistribute the load on the joint.

• High Tibial Osteotomy (HTO): For genu varum, a cut is made in the proximal tibia to open a medial wedge and shift the load towards the lateral compartment.

• Distal Femoral Osteotomy (DFO): For genu valgum, a cut is made in the distal femur to open a lateral wedge and shift the load towards the medial compartment.

These interventions aim to preserve the natural joint, delaying or preventing the need for a prosthesis.

• Epiphysiodesis (in pediatric age): In children and adolescents with open growth plates, growth of a part of the cartilage can be slowed or blocked to gradually correct the deformity.
• Arthroplasty (knee replacement): In patients with advanced osteoarthritis and angular deformity, especially in the elderly, total or partial knee replacement may be indicated.

Post-Surgical Recovery

Recovery after surgery for genu valgum or genu varum is a long process and requires an intensive and personalized rehabilitation program, under the guidance of a doctor or physical therapist.

• Initial phase: Pain and swelling management, recovery of passive mobility, isometric exercises.
• Intermediate phase: Recovery of active mobility, progressive muscle strengthening, partial or full weight-bearing according to the surgeon’s instructions.
• Advanced phase: Gait re-education, proprioceptive exercises, recovery of functional and sports activities.

The success of the intervention largely depends on the patient’s compliance with the rehabilitation program.

Frequently Asked Questions (FAQ)

Conclusion

Genu valgum and genu varum are complex conditions that require a multidisciplinary diagnostic and therapeutic approach. Understanding the causes, symptoms, and treatment options is fundamental for effective management. Although surgery is a solution for the most severe cases, physiotherapy and corrective exercises represent a cornerstone of conservative treatment, offering a significant opportunity to improve quality of life and prevent disease progression. It is always advisable to consult a doctor or physical therapist for an accurate evaluation and a personalized treatment plan.

Frequently Asked Questions

What are the common contributing factors to genu valgum and genu varum?

Muscle imbalances, flat feet, and certain postural issues are frequently associated with the development of genu valgum and genu varum. These factors can alter lower limb biomechanics, leading to uneven stress distribution across the knee joint.

What can I do to fix my knee alignment without surgery?

The main objectives of conservative management are to alleviate pain, enhance joint stability, and improve overall lower limb alignment. This approach typically involves specific exercises to strengthen supporting musculature and address biomechanical dysfunctions.

What are the potential long-term consequences if genu valgum or genu varum is not addressed?

If left unaddressed, genu valgum or genu varum can lead to chronic pain, increased joint instability, and accelerated cartilage degeneration. These long-term effects may predispose individuals to early onset osteoarthritis and other degenerative joint conditions.

How does a physical therapist assess genu valgum or genu varum?

A physical therapist assesses genu valgum or genu varum through a comprehensive evaluation of posture, gait, and lower limb biomechanics. This includes measuring angular deviations, identifying muscle imbalances, and assessing joint mobility to develop an individualized treatment plan.

Sources and Scientific References

1. (Extremely famous paper discussing how hip weakness causes dynamic knee valgus, perfectly addressing “Corrective Exercises” for valgus).
2. * *Study 4 (Surgery / Osteotomy for Varus/Valgus):*
3. * *Journal:* Knee Surgery, Sports Traumatology, Arthroscopy (KSSTA) or American Journal