Sural nerve pain is debilitating pain in the lower outer calf and foot. Usually, it comes from trauma to, or entrapment of, the sural nerve as it passes down the calf into the foot. So what is sural nerve pain, how do we diagnose it, and what’s the best treatment?
Sural nerve pain is one of several nerve entrapments of the calf and lower leg.
What is the sural nerve?
The sural nerve starts at the outer top of the lower leg and travels down the calf, close to the Achilles tendon. It winds around the outer part of the ankle — the lateral malleolus — to end at the outer part of the foot. It supplies sensation (such as light touch) from the outer lower leg to the outer heel, ankle, and foot. It’s a purely sensory nerve, so it doesn’t control any muscles.
Causes of sural nerve entrapment
Damage to the sural nerve has several causes:
- Direct trauma, such as a blow or fall onto the outer lower leg or calf
- Ankle fractures or sprains, which can damage the nerve as it passes close to the outer ankle
- Recent surgery, such as an Achilles tendon repair or metalwork, has been reported to cause sural nerve damage in up to 25% of percutaneous (keyhole) Achilles tendon repairs.
- Tight-fitting shoes or boots that compress the nerve and cause swelling
- Lumps, such as ganglions, are more commonly found around the ankle
Symptoms of sural nerve entrapment
Sural nerve damage usually causes pain in the outer lower leg. The pain is typically burning, but can also be sharp or shooting. Sometimes it radiates down into the outer foot or up into the upper calf.
Sural nerve pain can be present at rest and worsened by activity such as fast walking or running. Sitting or driving can also worsen symptoms by increasing tension on the sural nerve.
How do we diagnose sural nerve pain?
People with sural nerve irritation are sensitive to touch over the outer calf and lower leg. Tapping the nerve at the trapping site often causes a sharp, shooting pain. Your doctor examines the calf and foot for sensitivity along the nerve’s course, and adds neural stretching tests such as the slump or straight-leg-raise test.
It’s essential to exclude other causes of outer calf and foot pain — referred pain from the spine, calf tears, ankle sprains or fractures, and peroneal or Achilles tendonitis.
Investigations help confirm the diagnosis. An MRI may show inflammation of the nerve at the site of damage, but in many cases, there is no clear inflammation, and the scan reads as normal. Ultrasound is more useful: we follow the nerve’s course from the calf, looking for signs of inflammation or entrapment. Nerve damage usually appears as a sudden thickening of the nerve at the trapping site.
Sural nerve pain treatment
Exercises to relieve sural nerve pain
When we suspect sural nerve pain, we start with simple treatments: ankle and foot joint mobilisation, soft-tissue therapy to the tender areas, and appropriate footwear to reduce pressure on the nerve. Simple nerve stretches — sural nerve glides — help loosen the nerve and reduce irritation, along with gentle calf, hamstring, and pelvic stretches.
Medications
Topical and oral medications can help. Anti-inflammatory creams such as diclofenac (Voltarol) or piroxicam (Feldene) rubbed over the tender area reduce nerve swelling and ease pain. Medications used for nerve pain — amitriptyline or duloxetine — can make the nerve less painful. A doctor must prescribe these, and they have side effects.
Ultrasound-guided cortisone injection
In some cases of sural nerve entrapment, a cortisone injection directed to the entrapment site can improve symptoms. This must be performed under ultrasound guidance to improve accuracy and effectiveness.
Nerve hydrodissection
Nerve hydrodissection is an advanced procedure that injects a high volume of fluid to separate the nerve from surrounding scar tissue or adhesions. We generally use local anaesthetic, sterile water, or dextrose with a small dose of cortisone. It can be more effective than a simple cortisone injection.
Surgery
Finally, surgical release or decompression of the nerve may be needed in cases that fail all other treatments. One study found mixed results from surgical excision of a neuroma and re-implantation, so surgery is a last resort.
Frequently asked questions about sural nerve pain
What does sural nerve pain feel like?
Usually, a burning pain over the outer lower leg, sometimes sharp or shooting, that can radiate into the outer foot or up the calf. Because the sural nerve is purely sensory, there’s no muscle weakness — just pain, and sometimes altered sensation or numbness.
Can sural nerve pain go away on its own?
It can, particularly when the cause is removed—for example, by changing tight footwear —or as the nerve recovers after surgery or injury. Simple treatments and nerve glides speed this. Persistent pain beyond a few weeks should be assessed.
Why does sural nerve pain often follow ankle surgery?
The sural nerve runs close to the outer ankle and Achilles tendon, so it’s vulnerable during surgery in that area. Sural nerve damage has been reported in up to 25% of percutaneous Achilles tendon repairs, which is why new outer ankle or calf pain after such surgery warrants evaluation.
Is sural nerve pain the same as sciatica?
No. Sciatica comes from a pinched nerve in the lower back and affects a much larger area of the leg. Sural nerve pain is confined to the outer lower leg and foot. That said, referred pain from the spine can mimic it, which is why your doctor checks the back too.
How is sural nerve pain best diagnosed?
Clinically, the pattern of pain and tenderness along the nerve, supported by ultrasound, follows the nerve and shows thickening at the trapping site. Ultrasound is generally more useful than MRI here, as many cases look normal on MRI.
Final word from Sport Doctor London about sural nerve entrapment
Sural nerve pain is an uncommon cause of outer calf and foot pain, often due to entrapment or irritation after an injury or surgery. See a doctor skilled in diagnosing it — ultrasound expertise helps identify the site of entrapment and can guide a cortisone injection if needed.
To book a one-stop calf and ankle assessment with Dr Masci in London, contact the team here or call +44 (0) 203 488 0350.
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