Varus Deviation: Understanding Causes, Symptoms, and Management

What is varus deviation?

Varus deviation refers to an angular deformity where a distal segment of a limb or body part deviates medially (inward) relative to its more proximal segment, creating an angle that points away from the midline of the body.

Understanding Anatomical Terminology

To grasp varus deviation, it's essential to understand the basic anatomical terms:

• Varus: An angulation that points inward, causing the distal part of the limb to be angled towards the midline of the body. Think of the "bow" in "bow-legged."
• Valgus: The opposite of varus; an angulation that points outward, causing the distal part of the limb to be angled away from the midline. Think of "knock-knees."
• Medial: Towards the midline of the body.
• Lateral: Away from the midline of the body.

In a varus deformity, the joint angle opens laterally, resulting in the distal segment moving medially. This often leads to increased compressive forces on the medial side of the joint and increased tensile forces on the lateral side.

Where Varus Deviation Commonly Occurs

Varus deviation can manifest in various joints throughout the body, each with specific implications:

• Knee (Genu Varum or "Bow-leggedness"):

  • This is perhaps the most recognized form of varus deviation. In genu varum, the tibias (shin bones) angle inward relative to the femurs (thigh bones), causing the knees to appear bowed outward while the ankles remain closer together.
  • Impact: This alignment places disproportionate stress on the medial compartment of the knee joint, increasing the risk of medial meniscal tears and medial compartment osteoarthritis due to uneven load distribution.

• Ankle (Talocrural Varus or Hindfoot Varus):

  • Involves an inward angulation of the ankle joint, causing the heel to turn inward. This means the calcaneus (heel bone) is inverted relative to the tibia.
  • Impact: Often associated with chronic ankle instability and a higher propensity for lateral ankle sprains, as the foot is already positioned in an inverted state.

• Forefoot Varus:

  • A congenital condition where the forefoot (front part of the foot) is inverted relative to the rearfoot when the subtalar joint is in its neutral position.
  • Impact: To get the forefoot flat on the ground during gait, the subtalar joint must compensate by pronating excessively. This can lead to overuse injuries like plantar fasciitis, shin splints, and patellofemoral pain syndrome due to altered biomechanics up the kinetic chain.

• Elbow (Cubitus Varus):

  • An inward angulation of the forearm relative to the humerus (upper arm bone) when the arm is extended. It's often a common complication following a supracondylar fracture of the humerus in children, leading to a "gunstock deformity."
  • Impact: While often cosmetic, severe cases can affect elbow function or lead to nerve impingement.

• Hip (Coxa Vara):

  • Refers to a decreased angle between the neck and shaft of the femur (less than the normal 120-135 degrees), causing the femoral shaft to angle more medially.
  • Impact: Can alter hip joint mechanics, potentially leading to a Trendelenburg gait, leg length discrepancy, and increased stress on the femoral neck, increasing the risk of fracture.

Causes and Contributing Factors

Varus deviations can arise from a combination of factors:

• Congenital and Developmental Conditions:

  • Genetics: Predisposition to certain skeletal alignments.
  • Blount's Disease: A growth disorder affecting the growth plates of the tibia, leading to progressive bowing of the leg, particularly in children.
  • Rickets: A softening and weakening of bones in children, usually due to prolonged vitamin D deficiency, which can lead to bone deformities.
  • Slipped Capital Femoral Epiphysis (SCFE): In adolescents, the head of the femur slips backward off the neck, which can lead to coxa vara.

• Trauma:

  • Fractures: Improper healing of a fracture, especially around a joint (e.g., supracondylar humeral fracture, tibial plateau fracture), can result in a varus deformity.
  • Ligamentous Injuries: Chronic instability from ligamentous laxity or tears can lead to altered joint mechanics and subsequent deviation.

• Degenerative Conditions:

  • Osteoarthritis: Particularly in the knee, long-standing medial compartment osteoarthritis can lead to a progressive varus deformity as cartilage wears away on the inner side of the joint.

• Muscle Imbalances and Weakness:

  • While not a primary cause of structural varus, muscle imbalances (e.g., weak hip abductors, tight adductors) can exacerbate a pre-existing varus alignment or contribute to functional varus during movement.

• Biomechanical Factors:

  • Gait Abnormalities: Compensatory walking patterns can place uneven stress on joints over time.
  • Foot Mechanics: Conditions like forefoot varus can drive compensatory movements higher up the kinetic chain.

Signs, Symptoms, and Functional Implications

Recognizing varus deviation involves observing both static posture and dynamic movement:

• Visible Deformity: The most obvious sign is the characteristic angular alignment, such as bow-leggedness in genu varum.
• Pain: Localized joint pain (e.g., medial knee pain in genu varum), often exacerbated by activity. Referred pain can also occur up or down the kinetic chain.
• Altered Gait: Compensatory walking patterns, such as a "waddling" gait or an increased reliance on foot supination to clear the ground.
• Reduced Range of Motion: Stiffness or limited movement in the affected joint, particularly in end-range positions.
• Increased Risk of Injury:
  • Ligamentous Strain: Due to increased tensile forces on the lateral side of the joint.
  • Meniscal Tears: Especially medial meniscus in genu varum.
  • Stress Fractures: Due to uneven load distribution on bones.
  • Muscle Strain/Overuse Injuries: Resulting from compensatory muscle activity.
• Impact on Exercise Performance: Difficulties with specific exercises (e.g., squats, lunges), reduced power output, and a tendency to adopt compensatory movement patterns during physical activity.

Diagnosis and Assessment

Diagnosis typically involves a multi-faceted approach:

• Clinical Examination:
  • Visual Inspection: Observing limb alignment in standing, sitting, and supine positions.
  • Palpation: Assessing tenderness, swelling, and muscle tone.
  • Range of Motion Assessment: Measuring active and passive joint movements.
  • Special Tests: Orthopedic tests to assess joint stability and integrity.
• Gait Analysis:
  • Observational Gait Analysis: Watching the individual walk to identify compensatory patterns, weight-bearing shifts, and foot strike mechanics.
  • Instrumented Gait Analysis: Using force plates, motion capture systems, and electromyography (EMG) for detailed biomechanical assessment in advanced settings.
• Imaging:
  • X-rays: Crucial for confirming skeletal alignment, especially weight-bearing views to assess joint space and angular deformities (e.g., mechanical axis alignment in the knee).
  • MRI (Magnetic Resonance Imaging): To assess soft tissue structures like cartilage, ligaments, and menisci.
• Functional Movement Screens: Tools like the Functional Movement Screen (FMS) or Selective Functional Movement Assessment (SFMA) can help identify how varus deviation impacts overall movement patterns and contributes to dysfunction.

Management and Corrective Strategies

Management of varus deviation depends on its severity, cause, and the presence of symptoms. It often involves a combination of conservative and, in some cases, surgical approaches.

• Conservative Approaches:

  • Physical Therapy:
    • Strengthening: Targeting muscles that can help stabilize the joint and counteract the deviation (e.g., hip abductors, gluteal muscles, quadriceps, tibialis anterior).
    • Stretching: Addressing muscle tightness that may contribute to or exacerbate the deformity.
    • Neuromuscular Re-education: Improving proprioception, balance, and motor control to optimize movement patterns.
    • Gait Retraining: Teaching more efficient and less stressful walking patterns.
  • Orthotics and Bracing:
    • Shoe Inserts (Orthoses): Custom or off-the-shelf inserts can help correct foot mechanics (e.g., for forefoot varus) and influence alignment higher up the kinetic chain.
    • Knee Braces: Unloader braces can be used for genu varum to shift weight away from the medial compartment of the knee.
  • Activity Modification: Adjusting or avoiding activities that exacerbate pain or stress the affected joint. Modifying exercise technique to ensure proper alignment.
  • Weight Management: Reducing body weight significantly lessens the load on weight-bearing joints, particularly the knees.
  • Pain Management: Over-the-counter pain relievers (NSAIDs), ice, and heat can help manage symptoms.

• Surgical Intervention:

  • Reserved for severe cases, progressive deformities, or when conservative measures fail.
  • Osteotomy: A common procedure where a wedge of bone is either removed or added to realign the limb and redistribute joint forces (e.g., High Tibial Osteotomy for genu varum to shift load from the medial to the lateral compartment of the knee).
  • Joint Replacement: In cases of severe degenerative arthritis secondary to varus deformity (e.g., total knee arthroplasty).
  • Corrective Surgery for Developmental Deformities: Procedures to address conditions like Blount's disease or SCFE.

Role of Exercise and Movement Professionals

Fitness professionals, personal trainers, and kinesiologists play a crucial role in managing and educating clients about varus deviation:

• Assessment and Identification: Being able to recognize the signs of varus deviation during static posture assessment and dynamic movement screens.
• Prescribing Targeted Exercises: Designing exercise programs that focus on strengthening weak muscles, improving flexibility, enhancing balance, and correcting dysfunctional movement patterns.
• Gait Retraining: Guiding clients through exercises and drills to improve walking and running mechanics, promoting a more balanced load distribution.
• Client Education: Explaining the condition in understandable terms, emphasizing the importance of adherence to exercise programs, and discussing lifestyle modifications.
• Referral: Knowing when a deviation falls outside the scope of practice and requires referral to a medical doctor, orthopedic specialist, or physical therapist for further diagnosis and treatment. This is particularly important for structural or symptomatic varus deviations.

Conclusion

Varus deviation is an anatomical alignment characterized by an inward angulation of a distal limb segment, with its most prominent manifestation seen in genu varum or "bow-leggedness." While sometimes congenital or post-traumatic, it can also be a progressive condition influenced by biomechanical stressors and degenerative changes. Understanding the specific type, cause, and functional implications of varus deviation is critical for effective management. For individuals in the fitness and health realm, a comprehensive approach involving appropriate assessment, targeted exercise, and, when necessary, referral to medical specialists, is key to mitigating symptoms, improving function, and reducing the long-term risk of joint degeneration and injury.