FHL tendinopathy is a common cause of pain in the back of the ankle, arch and big toe, especially in dancers, runners and jumping athletes. It often appears alongside other foot pain conditions or ankle pain related to overload.

The flexor hallucis longus tendon plays a major role in push-off during walking, running and rising onto the toes. Overload can lead to tendon irritation and reduced capacity, similar to other tendon healing problems we see in active people.

Early assessment by a physiotherapist can settle symptoms and guide a safe return to activity. Your therapist will also help identify training errors, footwear issues or muscle imbalances that commonly contribute to running injuries, ballet injuries and other lower-limb overload patterns.

What is FHL Tendinopathy?

The flexor hallucis longus (FHL) is a powerful muscle–tendon unit that runs behind the inside ankle bone, under the arch of the foot and into the base of the big toe. It supports balance and propulsion, and often becomes overloaded when foot mechanics or foot posture control are challenged.

FHL tendinopathy occurs when the tendon becomes irritated and structurally stressed through repeated loading. This pattern mirrors what we see in other sports physiotherapy presentations involving calf or big toe overload.

You may also hear the term FHL tenosynovitis, which describes inflammation around the tendon sheath. These often occur together and may also be influenced by limited calf range, which benefits from targeted muscle stretches and load correction strategies.

Who Gets FHL Tendinopathy?

FHL tendon pain commonly affects athletes and active individuals who rely on repeated forefoot push-off. This includes:

• Ballet dancers performing demi-pointe and pointe work — a group we commonly assist in our ballet injuries clinic.
• Long-distance runners, sprinters and trail runners.
• Athletes who jump, hop or change direction, such as football players, ice skaters, divers and gymnasts.
• People returning to activity after a break, especially if tendon load progresses too quickly.
• Workers who stand or walk for long periods on firm surfaces, contributing to foot pain conditions.

Understanding which activities aggravate symptoms helps guide early load modification and targeted rehabilitation.

Signs and Symptoms of FHL Tendinopathy

Symptoms usually build gradually rather than starting with a single incident. Common features include:

• Dull ache that may sharpen with push-off activities such as walking, running, jumping or hopping.
• Pain along the tendon at the back or inside of the ankle, under the arch or at the base of the big toe.
• Stiffness or pain when you first get moving, which may warm up then return later.
• Swelling or thickening along the inside of the ankle.
• Clicking, creaking or a catching sensation behind the ankle.
• Pain with big toe movement or when rising onto the toes or pointe.
• Occasional locking or catching of the big toe in more advanced cases.

A sudden direct knock to the back of the ankle can also irritate the tendon, but this is less common than overuse.

Causes and Risk Factors

FHL tendinopathy usually develops when the tendon is asked to cope with more load than it can currently tolerate. This often happens with:

• Rapid increases in training volume, intensity, jumps or pointe work.
• Hard or uneven training surfaces.
• Inadequate recovery between sessions.

Intrinsic (personal) factors that may raise your risk include:

• Poor foot and ankle control or flat feet.
• Weak calf, foot or hip muscles.
• Tight calf or big toe muscles that limit ankle or toe range.
• Previous ankle or foot injuries.

Extrinsic (external) factors can also contribute:

• Worn or unsupportive shoes, or sudden changes in footwear.
• Training errors such as “too much, too soon”.
• Insufficient warm-up and cool-down routines.
• Fatigue from busy schedules, overtraining or lack of sleep.

A physiotherapist can assess how these factors apply to you and plan targeted changes.

How is FHL Tendinopathy Diagnosed?

Diagnosis starts with a detailed discussion of your symptoms, training loads and footwear, followed by a physical examination.

Your physiotherapist will typically:

• Palpate (press) along the FHL tendon to confirm the painful area.
• Test ankle and big toe movement and strength.
• Assess balance, calf strength and foot posture.
• Watch you walk, rise onto your toes or perform sport-specific movements.

Imaging, such as ultrasound or MRI, is sometimes used in more complex or persistent cases to look for tendon thickening, sheath irritation or associated problems. Many people, however, do not require scans because clinical testing clearly points to FHL tendinopathy.

Your physiotherapist will also screen for other causes of ankle pain, foot pain and big toe pain to ensure you receive the right treatment.

Treatment Options for FHL Tendinopathy

Most people respond well to conservative management. Treatment focuses on reducing pain, improving tendon capacity and addressing the reasons the tendon became overloaded.

Load Management and Activity Modification

Completely stopping activity is rarely necessary. Instead, your physiotherapist will help you adjust:

• Training volume, intensity and surfaces.
• Jump, hop, pointe or sprint loads.
• Work tasks that involve long periods on your feet.

The goal is to keep you as active as possible while allowing the tendon to settle.

Exercise and Tendon Loading

Progressive strengthening is the cornerstone of modern tendon care. Your programme may include:

• Calf and FHL strengthening in different positions.
• Slow, heavy loading to build tendon capacity.
• Balance and control drills for the foot and ankle.
• Sport- or dance-specific plyometric progressions when appropriate.

For more information, see our tips on tendon healing and physiotherapy and active foot posture correction exercises.

Hands-On Treatment and Muscle Care

Targeted soft tissue techniques can help reduce muscle tension around the tendon. Your physiotherapist may use:

• Gentle stretching of the calf, foot and big toe.
• Soft tissue massage, trigger point work or transverse friction.
• Self-care tools such as foam rollers and trigger balls.

Footwear, Taping and Supports

Your physiotherapist may suggest:

• Footwear changes to improve support and comfort.
• Taping or temporary orthotic inserts to unload the tendon.
• Activity progressions that match your shoes and surfaces.

Medications and Injections

Short-term use of pain-relieving or anti-inflammatory medication may assist in the early phase. Your GP or sports doctor can advise you about tablets, topical agents or occasional injections when appropriate. These approaches work best when combined with a structured rehabilitation program.

Surgery

Surgery is only considered in advanced, long-standing cases that have not responded to high-quality conservative care. Post-operative physiotherapy then guides safe return to walking, work, dance and sport.

Rehabilitation and Return to Sport or Dance

Your rehabilitation plan will usually progress through stages:

• Settling pain and improving everyday walking comfort.
• Building strength in the calf, foot and big toe.
• Restoring single-leg control, balance and power.
• Gradually reintroducing running, jumping, hopping or pointe work.

Regular review helps fine-tune your program and adjust training loads. Many people improve over 6–12 weeks, although more chronic cases may need longer. Your physiotherapist will guide safe progressions so you feel confident returning to your chosen activity.

Can You Prevent FHL Tendinopathy?

You cannot remove all risk, but you can reduce it with good habits:

• Increase training loads gradually, especially when adding jumps or pointe work.
• Use supportive, activity-appropriate footwear.
• Include calf and foot strengthening in your regular program.
• Warm up before activity and cool down afterwards.
• Plan rest days and lighter weeks during heavy training blocks.

These strategies also help manage other foot pain conditions and ankle pain problems.

When Should You See a Physiotherapist?

Book a physiotherapy appointment if:

• Foot, ankle or big toe pain lasts longer than a couple of weeks.
• Pain limits running, dance, sport or work.
• You notice catching, locking or clicking around the inside of the ankle.
• Self-management and rest are not improving your symptoms.

Early guidance can reduce flare-ups, shorten recovery times and help you return to the activities that matter most to you.

People Also Ask: FHL Tendinopathy

Is FHL tendinopathy serious?

FHL tendinopathy is usually manageable with physiotherapy, but ignoring symptoms can lead to more persistent tendon changes and longer recovery times.

How long does FHL tendinopathy take to heal?

Many people improve within 6 to 12 weeks with a structured loading program and activity changes. Long-standing or severe cases may need a longer plan.

Can I keep running with FHL tendon pain?

Running is often modified rather than stopped completely. A physiotherapist can adjust distance, speed and terrain while you strengthen the tendon.

What makes FHL tendon pain worse?

Strong forefoot push-off, pointe work, hills, sudden training spikes and unsupportive footwear commonly aggravate FHL tendon symptoms.

Do I always need a scan for FHL tendinopathy?

No. Most cases are diagnosed clinically. Scans are reserved for more complex, persistent or unclear presentations.

Related Articles

1. Common Tendon Injuries – Overview of tendon injury types, symptoms and treatment options.
2. Foot Pain Conditions – Common causes of foot pain and when to seek care.
3. Tendon Healing: Physiotherapy Tips – Practical advice on loading, pain and recovery.
4. Ankle Pain Conditions – Information about ankle injuries and treatment options.
5. Active Foot Posture Correction Exercises – Exercises to support foot and ankle alignment.
6. When Should You Worry About Foot or Ankle Pain? – Guidance on red flags and when to book an appointment.
7. Why Warming Up Matters – How a warm-up protects muscles and tendons.

For an overview of tendinopathy research, see this tendinopathy review on NCBI.

Helpful Foot and Ankle Products

Many people with FHL tendinopathy benefit from simple home tools such as heat or ice packs, massage balls, arch supports and supportive braces. Ask your physiotherapist which products suit your stage of recovery.

Social Media

Stay informed about foot, ankle and tendon health by following PhysioWorks on social media. You will find practical exercise tips, injury prevention ideas and recovery stories to help you stay active and confident.

References

Recent research supports progressive tendon loading, biomechanical assessment and structured rehabilitation as key strategies for managing tendinopathy, including FHL involvement.

• Kaux JF, Forthomme B, Le Goff C, et al. Current opinions on tendinopathy. J Sports Sci Med. 2011;10(2):238-253.
• Deu RS, Deu SA. Tendinopathies of the foot and ankle. Am Fam Physician. 2022;105(5):479-488.