Unfortunately, some ankle sprains do not recover adequately with a comprehensive rehabilitation program alone. Our post “How to tell when it’s more than an ankle sprain” detailed some of the conditions that may indicate the need for surgery after a lateral ankle sprain. These include:

  • Ongoing instability – recurrent sprains
  • Persistent ankle pain

Before any type of surgical intervention, your ankle specialist will likely recommend you have an MRI of your ankle. This helps them to plan the operation as it gives them a clearer picture of the damage inside your ankle. It will show all the ligaments, tendons and bone surfaces. Damage to the surface of the bone inside a joint can be called an osteochondral defect, it is common after an ankle sprain for the talar bone to have osteochondral defects to its dome.


Modified Brostrom Procedure:

This is one of the most common procedures that ankle specialists use to stabilise an unstable ankle. In this procedure, your Anterior Talofibular ligament and your Calcaneofibular ligament are repaired anatomically.

For the operation, you are anaesthetised (unconscious) and laying on your back. The ankle specialist will make a cut on the outside of your ankle just in front of the ankle bone or lateral malleolus. The damaged ligaments are identified one at a time, and tagged with the strong fibre they will be repaired with. The base of your fibular (the bone on the outside of your lower leg) is then prepared for the ligaments to be attached back to. They are prepared by drilling 2-3 tunnels for the strong fibres tagging the ligaments to be tied into. Once the tunnels are drilled the strong fibre stitched into your ligament is anchored into the prepared bone tunnels. In some cases if your ligaments are not strong enough to hold the strong fibre stitches a graft may be taken from one of your ankle tendons to become your new ankle ligament or the specialist may use an internal brace (see below).


Arthroscopic Stabilisation:

An ankle can also be stabilised arthroscopically, this simply means that the operation occurs through smaller cuts (2-3), it is still done under anaesthetic. When suitable, this operation is less invasive than a traditional open (larger cut) operation, and the smaller wounds heal quicker. For an arthroscopic ankle stabilisation, one small cut is made at the front of the ankle joint and the second small cut is made just in front of the outside ankle bone. The ankle specialist places a narrow tube through one of the cuts which has a fibre-optic camera on it. Images from the camera of the inside of the ankle are projected onto a monitor in the operating theatre. The repair of the damaged ligaments is then done in a similar way to described above using specialised arthroscopy instruments through other small cuts.


Modified Brostrom with an Internal Brace:

If the damaged ligaments are unable to be repaired as described above (open or arthroscopically), your ankle specialist may use an internal brace to help recreate ligament stability in your ankle. This internal brace is a fibrous tape that acts as a splint or an augment for the damaged ligament. If an internal brace is used, it generally won’t need to be removed surgically later on.

After any of these operations you will wake up in recovery with a camboot or moon boot on your ankle. This protects the wounds and the ligament repairs (and internal brace) by stopping you from accidentally moving it in a way that will stress the repair. You won’t be able to walk on your operated leg for 2 weeks and will be in the boot for 6 weeks. During that first 2 weeks you can move your toes, knee, and hip freely. Your rehabilitation be guided by your treating therapist, return to sport can take 3 months.