Cavus Foot: Causes, Diagnosis, and Treatment Options
What Is Cavus Foot?
Cavus foot, also known as pes cavus, is a foot deformity characterized by an unusually high arch along the inner side of the foot. This condition can affect your ability to walk, run, or stand comfortably and may lead to pain or instability. It’s more common than many realize, affecting approximately 10% of adults. Though it can appear in childhood, cavus foot often becomes more pronounced over time, leading to stiffness and pain in the foot’s weight-bearing areas.
The arch of the foot plays a vital role in how we move. It acts like a spring to absorb shock and distribute body weight during each step. In people with cavus foot, this natural shock absorption is disrupted, potentially causing problems in the foot, ankle, knee, or even hips.
Why Does Cavus Foot Occur?
The primary cause of cavus foot is often a neuromuscular disorder—a condition that affects how nerves communicate with muscles. The most common of these is Charcot-Marie-Tooth (CMT) disease, a hereditary condition affecting peripheral nerves. In fact, about 78% of individuals with bilateral cavus foot (on both sides) are diagnosed with CMT.
Other potential causes include:
- Poliomyelitis
- Cerebral palsy
- Spinal cord tumors
- Traumatic brain or spinal injuries
- Conditions like spina bifida or tethered cord syndrome
These conditions can lead to muscle imbalances that pull the foot into a high-arched, inward-tilted position, often worsening over time.
Understanding the Biomechanics
Cavus foot is not just a high arch—it is a complex structural deformity. Key changes may include:
- Varus hindfoot (heel tilts inward)
- High calcaneal pitch (steep heel bone)
- Plantarflexed first ray (the first metatarsal points downward)
- Claw toe deformities
- Forefoot adduction (toes point inward)
During walking, these changes disrupt the foot’s ability to transition smoothly through the gait cycle. The midfoot’s “lock and unlock” mechanism—key to flexible motion—is impaired. As a result, pressure becomes concentrated along the outer (lateral) side of the foot, leading to pain, instability, and increased risk of injuries like stress fractures
.
Types of Cavus Foot
Since no two patients are the same, cavus foot is classified in different ways to guide diagnosis and treatment:
Based on Cause:
- Neuromuscular
- Congenital
- Acquired
- Idiopathic (no clear cause)
Based on Location:
- Forefoot-derived: Deformity originates in the front of the foot
- Hindfoot-derived: Deformity is driven by a tilted heel
- Mixed: Both front and back of the foot are involved
Based on Flexibility:
- Flexible: Correctable with tendon transfers
- Stiff: Requires soft tissue release
- Rigid: Needs bone surgery (osteotomy)
Symptoms and How It Affects Daily Life
Common symptoms include:
- Pain under the ball of the foot (metatarsalgia)
- Recurrent ankle sprains or instability
- Calluses under the heel or metatarsals
- Claw toes
- Knee or hip pain due to gait compensation
Diagnosis: Physical and Radiographic Evaluation
Physical Exam
A thorough physical exam begins with a detailed medical and family history. Sometimes, cavus foot runs in families. The exam includes observing walking patterns, foot alignment, muscle strength, and the flexibility of the foot.
One critical test is the Coleman Block Test. It helps determine whether the deformity is coming from the forefoot or the heel. If the heel corrects itself when the first toe is lifted on a block, the issue is likely forefoot-driven.
Imaging
Weight-bearing X-rays are essential. They help visualize:
- The angles between key bones (e.g., Meary’s angle, calcaneal pitch)
- Where the apex of the deformity lies
- Whether arthritis is present
- If the heel bone is tilted (varus)
Advanced imaging like CT or MRI may be used in complex cases or if soft-tissue injuries are suspected. Gait analysis and nerve studies (EMG) may also be done to better understand muscle function and neurologic involvement
Treatment Options
Non-Surgical Treatments
For mild cases, the following may help:
- Orthotic insoles to support the arch and redistribute pressure
- Stretching exercises for the calf muscles and Achilles tendon
- Anti-inflammatory medications
- Activity modification
However, conservative treatments often provide only temporary relief, especially in progressive or severe cases.
Surgical Treatments
The goal of surgery is a painless, stable, and plantigrade foot—a foot that makes full contact with the ground.
Surgery is typically personalized and may involve:
- Soft tissue procedures – to release tight tendons, ligaments, or fascia (e.g., plantar fascia release, Achilles tendon lengthening)
- Tendon transfers – to restore muscle balance (e.g., transferring peroneus longus to brevis to stop pulling the big toe downward)
- Osteotomies – cutting and realigning bones to correct deformity
- Arthrodesis (fusion) – used when joints are stiff, painful, or arthritic
- Use of 3D planning and printing – to guide precise bone cuts, improving surgical accuracy
Midfoot osteotomies like the Cole, Japas, or Akron are commonly used depending on the location and severity of the deformity. Hindfoot surgeries like the Dwyer or Z-shaped calcaneal osteotomies are used when heel correction is needed
Innovations: 3D Planning and Digital Orthopedics
New technologies are making surgery safer and more accurate. Surgeons now use:
- 3D simulation to model deformities
- Printed cutting guides for more precise bone surgery
- Computer-assisted planning to visualize postoperative alignment before the first incision
These tools are especially useful in complex, multiplanar deformities and may lead to faster recovery and fewer complications.
Final Thoughts
Cavus foot is a complex condition requiring expert evaluation and often a multi-step treatment plan. With personalized care—including physical therapy, orthotics, and advanced surgical options—most patients can achieve significant relief and regain normal foot function.
If you or a loved one experiences symptoms of cavus foot, early diagnosis and a tailored treatment strategy are key. Reach out to a qualified orthopedic specialist to start the journey toward a more comfortable step.
Dr. Mo Athar
