Patient Education · Foot & Ankle

Peroneal Tendon Repair

Pain behind the outer ankle bone that never settled after a sprain. Often it is not the ligament at all — it is the tendons running just behind it.

Dr. Darin W. Allred Darin W. Allred, MD Board-certified orthopedic surgery & sports medicine
~1 hrTypical time for the operation
2 weeksNo weight on the foot
Behind the boneWhere the pain sits, and the clue that it is tendon
4–6 moBack to full activity

What these tendons do

Two tendons run down the outside of your calf, curve behind the bony knob of your outer ankle, and continue into the foot. They live in a shallow groove in the bone, held in place by a band of tissue over the top.

Their job is to turn the foot outward and, more importantly, to actively stop your ankle rolling inward. They are the muscles that catch you when you step on uneven ground.

What goes wrong

Because they wrap around a bony corner under tension, they take a lot of wear. Three things happen there:

  • A split tear. The tendon frays lengthwise, like a rope splitting along its fibers.
  • Tendinitis and thickening, with inflamed tissue crowding the space they run in.
  • Subluxation — the tendons slipping forward out of their groove over the bone. People sometimes feel or hear a snap on the outside of the ankle, and can occasionally reproduce it.

The common thread is an ankle that has been sprained repeatedly. A groove that is naturally shallow, or a band that stretched during an old sprain, makes it more likely.

How to tell it apart from a sprain

Location is the clue. A ligament sprain hurts in front of and below the outer ankle bone. Peroneal tendon trouble hurts behind and below it, along the line of the tendons, and the pain follows that line up the leg. If your "ankle sprain" never settled and the tenderness sits behind the bone rather than in front of it, this is worth investigating.

Other signs: swelling that follows the tendon line, pain turning the foot outward against resistance, and a sense that the ankle keeps giving way — which is easy to mistake for ligament instability, and often coexists with it.

What to try first

  • Strengthening those muscles, and balance training.
  • A brace or supportive footwear for uneven ground.
  • Relative rest and anti-inflammatories for a genuine flare.
  • A lateral heel wedge where the foot shape is loading the outer side of the ankle.

Tears that are small and stable often settle. I move toward surgery when a proper program has not worked, when the tendon is significantly torn on imaging, or when the tendons are slipping out of their groove — because that last one does not resolve on its own.

How the operation goes

  1. Anesthesia. General or spinal with a block. You go home the same day.
  2. An incision along the line of the tendons behind the outer ankle bone.
  3. Open the sheath and inspect both tendons along their length — the damage is often more extensive than the scan suggested.
  4. Clear the diseased tissue and repair the split, sewing the tendon back into a smooth tube.
  5. Deepen the groove if the tendons have been slipping, so they sit properly and stay put.
  6. Repair the retaining band over the top, and close.

If one tendon is beyond saving, it can be joined to its healthy neighbor — the two work together, and that solution holds up well.

An unstable ankle is often stabilized at the same time. If a ligament reconstruction was done alongside this, your recovery follows this slower pathway, not the ligament one.

Recovery

  • Weeks 0–2No weight on the foot. Splint or boot, foot held neutral. Elevate. Keep the incision dry. Aspirin 81 mg twice daily for two weeks. Stitches out around two weeks.
  • 2–6 weeksWeight bearing progresses in the boot on the schedule in your protocol. Gentle motion begins. Turning the foot inward is avoided while the repair heals.
  • 6–12 weeksOut of the boot, into a brace for a while. Strengthening those outer-calf muscles, and balance work.
  • 3–6 monthsProgressive return to full activity and uneven ground. Many people keep a lace-up brace for sport the first season.

The risks, honestly

  • Ongoing pain The most common disappointment. These tendons sit in a tight space and the tissue is often chronically degenerated, so some soreness can persist.
  • The tendons slip again Uncommon after groove deepening, more likely if the retaining band was already poor quality.
  • Nerve irritation A nerve runs close to this incision; numbness along the outer foot is not unusual and usually fades.
  • Stiffness Some loss of motion, usually turning the foot inward — and given the history, that is often no bad thing.
  • Wound problems Uncommon; elevation early is what prevents them.
  • Blood clots The reason for the aspirin and for keeping the rest of you moving.
This page is general education. It describes how I approach this and what most patients experience. If anything here does not match what you were told in clinic, ask — your own instructions always come first.