Heel Varus: Causes, Symptoms, Diagnosis, and Management

What is Heel Varus?

Heel varus, also known as calcaneal varus, describes a biomechanical alignment where the heel bone (calcaneus) is inverted or angled inward relative to the ground when weight-bearing. This inward tilt places increased stress on the lateral (outer) aspect of the foot and can significantly impact the entire kinetic chain.

Understanding Normal Foot Alignment

To appreciate heel varus, it's essential to understand ideal foot alignment. In a neutral, weight-bearing position, the calcaneus should be perpendicular to the ground, or slightly everted (tilted outward). This allows for even distribution of weight across the heel and forefoot, and proper shock absorption through the foot's arch mechanisms. The subtalar joint, which connects the talus and calcaneus, plays a crucial role in adapting the foot to uneven surfaces and absorbing ground reaction forces.

What is Heel Varus? A Deeper Dive

Heel varus specifically refers to an inversion of the calcaneus in the frontal plane. When observed from behind, the heel appears to lean inward, with the lateral side of the heel bone sitting higher than the medial side. This position forces the subtalar joint into a supinated (inverted and adducted) alignment during the stance phase of gait.

It is important to differentiate heel varus from forefoot varus, which refers to an inversion of the forefoot relative to the rearfoot when the subtalar joint is in neutral. While both involve an inward tilt, heel varus is a rearfoot deformity that directly impacts initial ground contact and the subsequent pronation mechanics necessary for shock absorption. A rigid heel varus can prevent the foot from pronating sufficiently, leading to a host of compensatory issues up the kinetic chain.

Causes and Contributing Factors

Heel varus can be attributed to a combination of structural, biomechanical, and sometimes neurological factors:

• Structural/Anatomical Factors:
  • Inherited Foot Type: Individuals with naturally high-arched feet (pes cavus) often present with a structural heel varus. The bony architecture of the calcaneus itself may be angled.
  • Tibial Varum: An inward bowing of the tibia (shin bone) can contribute to a compensatory heel varus as the foot attempts to achieve ground contact.
  • Tarsal Coalitions: Abnormal fusions between bones in the midfoot or hindfoot can restrict normal motion and lead to fixed deformities.
• Biomechanical Factors:
  • Limited Ankle Dorsiflexion: Tightness in the calf muscles (gastrocnemius and soleus) can force the subtalar joint into supination to allow the tibia to advance over the foot during gait.
  • Muscle Imbalances: Weakness in the ankle evertor muscles (peroneals) or overactivity of invertor muscles (tibialis anterior, tibialis posterior) can contribute to an inverted heel position.
  • Compensatory Mechanisms: Heel varus can sometimes be a compensation for other issues, such as a leg length discrepancy or hip abductor weakness.
• Neurological Conditions: Certain neurological conditions leading to muscle spasticity or imbalance can contribute to fixed or dynamic heel varus.
• Trauma: Previous ankle or foot injuries can alter joint mechanics and lead to a varus deformity over time.
• Inappropriate Footwear: Shoes lacking adequate support or those that push the foot into an inverted position can exacerbate existing tendencies.

Associated Conditions and Symptoms

The altered biomechanics resulting from heel varus can lead to a variety of musculoskeletal issues due to improper load distribution and compensatory movements:

• Lateral Ankle Instability and Sprains: The inverted position places the ankle in a vulnerable state, increasing the risk of recurrent inversion ankle sprains.
• Peroneal Tendinopathy: The peroneal muscles on the outside of the ankle work harder to try and evert the foot, leading to overuse injuries and inflammation of their tendons.
• Stress Fractures: Increased impact forces on the lateral side of the foot can lead to stress fractures, particularly in the fifth metatarsal.
• Lateral Shin Splints: Pain along the outside of the shin due to overuse of muscles attempting to control foot position.
• Plantar Fasciitis: While less common than with pronated feet, heel varus can lead to plantar fasciitis due to the rigidity of the foot and the inability to absorb shock effectively, placing strain on the plantar fascia.
• Callus Formation: Excessive pressure on the lateral aspect of the heel and fifth metatarsal head can lead to painful calluses.
• Knee Pain: The rigid, supinated foot can lead to compensatory internal rotation of the tibia and increased stress on the lateral compartment of the knee, potentially contributing to iliotibial band (ITB) syndrome or lateral patellofemoral pain.
• Hip and Lower Back Pain: The altered kinetic chain can extend up to the hip and lower back, contributing to various musculoskeletal complaints.

Diagnosis of Heel Varus

A thorough diagnosis of heel varus involves a comprehensive clinical assessment by a healthcare professional, such as a podiatrist, physical therapist, or orthopedic surgeon.

• Clinical Examination:
  • Visual Inspection: Observing the foot and ankle alignment in both non-weight-bearing and weight-bearing positions (static assessment).
  • Gait Analysis: Observing walking patterns to identify how the heel contacts the ground and how the foot moves through the stance phase (dynamic assessment). Look for excessive wear on the lateral heel of shoes.
  • Range of Motion Assessment: Evaluating the flexibility of the ankle joint (especially dorsiflexion) and the subtalar joint.
  • Palpation: Identifying areas of tenderness, muscle tightness, or weakness.
• Footwear Analysis: Examining the wear patterns on the soles of the patient's shoes can provide clues about their foot mechanics.
• Imaging Studies: In some cases, weight-bearing X-rays may be used to assess the bony alignment of the calcaneus and other foot structures, helping to differentiate between flexible and rigid deformities.

Management and Treatment Strategies

Treatment for heel varus aims to reduce symptoms, improve biomechanics, and prevent further complications. Management typically begins with conservative approaches.

• Conservative Approaches:

  • Orthotics: Custom-made or over-the-counter orthotic devices are often the cornerstone of treatment. They are designed to provide support and medial wedging to bring the heel into a more neutral or slightly everted position, improving shock absorption and load distribution.
  • Footwear Modification: Choosing stable shoes with good arch support and a firm heel counter is crucial. Avoid minimalist or excessively flexible footwear.
  • Physical Therapy and Rehabilitation:
    • Stretching: Focus on stretching tight calf muscles (gastrocnemius and soleus) and the plantar fascia.
    • Strengthening: Exercises to strengthen the ankle evertor muscles (peroneals) and intrinsic foot muscles to improve stability and control.
    • Gait Retraining: Education on proper walking mechanics to encourage a more neutral foot strike.
    • Balance and Proprioception Exercises: To improve ankle stability and reduce the risk of sprains.
  • Manual Therapy: Techniques to mobilize stiff joints in the foot and ankle, improving overall flexibility.
  • Pain Management: Non-steroidal anti-inflammatory drugs (NSAIDs) or ice application may be used to manage acute pain and inflammation.

• Surgical Intervention:

  • Surgery is typically reserved for severe, rigid heel varus deformities that have not responded to conservative management and are causing significant pain or functional limitation. Procedures may involve osteotomies (bone cuts) to realign the calcaneus or fusions to stabilize the subtalar joint.

Prevention and Long-Term Considerations

While some structural heel varus may be inherited, certain strategies can help prevent associated problems and manage the condition long-term:

• Appropriate Footwear: Consistently wearing supportive shoes that fit well and accommodate any prescribed orthotics.
• Regular Stretching and Strengthening: Incorporating exercises for calf flexibility and foot/ankle strength into a regular routine.
• Gradual Progression in Activity: Slowly increasing the intensity and duration of physical activities to allow the feet and body to adapt.
• Early Intervention: Seeking professional assessment for persistent foot or ankle pain to address issues before they become chronic.

Conclusion

Heel varus is a significant biomechanical alignment issue characterized by an inward tilt of the heel. While it can be a structural finding, its implications extend beyond the foot, affecting the entire kinetic chain and predisposing individuals to a range of musculoskeletal problems, particularly on the lateral aspect of the lower limb. Accurate diagnosis through clinical assessment and gait analysis is crucial for developing an effective management plan. Conservative treatments, primarily orthotic therapy, supportive footwear, and targeted physical therapy, are highly effective in correcting alignment, alleviating symptoms, and improving overall function, helping individuals maintain an active and pain-free lifestyle.