Nerve Compression Injuries: Tarsal Tunnel Syndrome in Runners

Quick Summary

Tarsal Tunnel Syndrome (TTS) is a less common but debilitating nerve compression injury that affects runners. It occurs when the posterior tibial nerve, located near the ankle, becomes compressed, causing pain, tingling, or numbness in the foot and ankle. This article explores the causes, symptoms, and treatment strategies for TTS, with a focus on how runners can prevent and manage this condition while maintaining their training.

Introduction: The Hidden Agony of Nerve Compression

For runners, the foot is both a tool and a vulnerable point. Each stride places stress on the intricate structures of the foot, including muscles, tendons, and nerves. When the posterior tibial nerve, which runs through a narrow passage near the inner ankle (the tarsal tunnel), becomes compressed, it can lead to Tarsal Tunnel Syndrome (TTS).

Unlike more familiar running injuries like shin splints or plantar fasciitis, TTS often goes undiagnosed or is mistaken for other foot problems. However, for those who experience its sharp, radiating pain, the condition is anything but insignificant. Runners with TTS may struggle with every step, their performance hindered by persistent discomfort.

Understanding the mechanics of TTS and how to address it can help runners return to pain-free training and prevent future nerve compression injuries.

What is Tarsal Tunnel Syndrome?

Tarsal Tunnel Syndrome is a nerve compression injury that affects the posterior tibial nerve, which runs through the tarsal tunnel—a narrow space located behind the medial malleolus (the bony bump on the inside of the ankle). This tunnel is bordered by bones and covered by the flexor retinaculum, a thick ligament that holds the structures in place.

When swelling, inflammation, or anatomical abnormalities narrow the tunnel, the posterior tibial nerve becomes compressed, leading to symptoms that can range from mild discomfort to severe, burning pain. The condition is analogous to carpal tunnel syndrome in the wrist but occurs in the foot and ankle.

Why Runners Are Susceptible to Tarsal Tunnel Syndrome

Runners are particularly prone to TTS due to the repetitive impact and strain placed on the feet and ankles. Factors contributing to TTS in runners include:

1. Overuse and High Mileage

Repetitive pounding during long runs or high-mileage weeks can inflame the tendons and soft tissues surrounding the posterior tibial nerve, narrowing the tarsal tunnel.

2. Biomechanical Issues

• Overpronation: Excessive inward rolling of the foot stretches the structures around the tarsal tunnel, increasing compression on the nerve.
• Flat Feet: A collapsed arch reduces the space in the tarsal tunnel, heightening the risk of nerve compression.

3. Ill-Fitting Shoes

Shoes that are too tight or lack proper arch support can place additional pressure on the posterior tibial nerve.

4. Ankle Injuries

Previous sprains, fractures, or other trauma to the ankle can lead to scar tissue or swelling, which may constrict the tarsal tunnel.

5. Running Surfaces

Hard or uneven surfaces increase the impact on the foot, contributing to inflammation and irritation of the tarsal tunnel structures.

Symptoms of Tarsal Tunnel Syndrome

TTS symptoms vary in severity but typically worsen with activity and improve with rest. Common symptoms include:

• Pain: A burning, tingling, or shooting pain on the inside of the ankle and foot.
• Numbness: A "pins and needles" sensation in the sole of the foot or toes.
• Swelling or Tenderness: The area around the medial malleolus may appear swollen or feel tender to the touch.
• Radiating Pain: Discomfort may spread to the heel, arch, or toes, depending on the extent of nerve involvement.
• Weakness in the Foot: Severe cases may result in difficulty flexing or curling the toes.

Diagnosing Tarsal Tunnel Syndrome

Accurate diagnosis of TTS often requires a combination of:

• Physical Examination: A doctor may press on the tarsal tunnel to reproduce symptoms. The Tinel’s sign test, where tapping over the nerve produces tingling, is often used.
• Imaging Tests: An MRI or ultrasound can identify swelling, anatomical abnormalities, or scar tissue compressing the nerve.
• Electrodiagnostic Testing: Nerve conduction studies can confirm the presence of nerve compression.

Treating Tarsal Tunnel Syndrome

Recovery from TTS requires addressing both the symptoms and the underlying causes. Early intervention is crucial to prevent permanent nerve damage.

1. Rest and Activity Modification

• Reduce or stop running temporarily to allow inflammation to subside.
• Engage in low-impact activities like swimming or cycling to maintain fitness without aggravating symptoms.

2. Anti-Inflammatory Treatments

• Ice Therapy: Apply ice to the affected area for 15–20 minutes, several times a day, to reduce swelling.
• NSAIDs: Over-the-counter non-steroidal anti-inflammatory drugs can relieve pain and inflammation.

3. Orthotics and Footwear

• Use custom or over-the-counter orthotics to correct overpronation or flat feet.
• Switch to running shoes with better arch support and cushioning.

4. Physical Therapy

Physical therapy focuses on improving strength, flexibility, and biomechanics. Key exercises include:

• Calf Stretches: Reduce tension on the posterior tibial nerve.
• Ankle Strengthening: Use resistance bands to strengthen the muscles around the ankle.
• Nerve Gliding Exercises: Mobilize the posterior tibial nerve to reduce compression.

5. Corticosteroid Injections

In cases of severe inflammation, corticosteroid injections can provide temporary relief by reducing swelling around the nerve.

6. Surgery

If conservative treatments fail, surgical decompression of the tarsal tunnel may be necessary. This procedure involves releasing the flexor retinaculum to create more space for the nerve.

Preventing Tarsal Tunnel Syndrome

Prevention focuses on minimizing stress on the tarsal tunnel and maintaining healthy foot mechanics. Here’s how runners can reduce their risk:

1. Strengthen and Stretch the Feet and Ankles Regularly perform exercises to improve foot and ankle strength and flexibility. Focus on calf stretches, toe curls, and ankle rotations.
2. Wear Proper Shoes Invest in running shoes that fit well and provide adequate support. Replace shoes regularly to ensure optimal cushioning.
3. Use Orthotics if Needed If you have flat feet or overpronation, custom orthotics can help maintain proper foot alignment.
4. Gradually Increase Training Avoid sudden increases in mileage or intensity. Follow the 10% rule to allow your body to adapt to increased demands.
5. Run on Soft Surfaces Whenever possible, choose trails, grass, or rubberized tracks over concrete to reduce impact on the feet.

Recommended Books

1. "Anatomy for Runners" by Jay Dicharry
   A biomechanical guide to running that includes strategies for preventing nerve compression injuries.
2. "Fixing Your Feet" by John Vonhof
   A comprehensive resource on foot care, including advice on managing and preventing nerve-related injuries.
3. "Running Strong" by Jordan Metzl
   This book provides practical tips for injury prevention and recovery, including nerve-related conditions like TTS.

Related Articles on RockingUltra

1. "Plantar Fasciitis: Breaking the Cycle of Heel Pain"
   Explore another common running injury affecting the foot.
2. "Shin Splints: The Runner’s Struggle with Tibial Pain"
   Insights into managing another overuse injury common among runners.
3. "Overtraining Syndrome: When Too Much Running Backfires"
   A broader look at how overtraining can lead to injuries like TTS.

Conclusion: Freeing the Nerve, Freeing the Stride

Tarsal Tunnel Syndrome is a challenging condition, but with early recognition and targeted treatment, it’s possible to overcome. By addressing biomechanical issues, choosing proper footwear, and strengthening the feet and ankles, runners can protect the posterior tibial nerve and enjoy pain-free miles. Remember, running is about balance—both in training and in caring for the body that carries you.

Next Article in the Series:

"Achilles Tendinopathy: The Runner’s Greatest Heel"
This article will explore the causes, symptoms, and treatments for Achilles tendinopathy, focusing on how to manage and prevent this common injury among endurance athletes.