Supramalleolar osteotomy (SMOT)

Realignment surgery to relieve pressure on part of the ankle joint affected by arthritis

In some patients they have pain and early arthritis in one spot in the ankle. This is due to a malalignment (incorrect position) of the tibia bone above the ankle. In these patients a correction of the ankle involves cutting a resetting the bone (osteotomy) of the tibia above the ankle.

The goal of this surgery is to re-align the leg to a more “normal” position to improve the biomechanics and hence pain. Sometimes a slightly abnormal position is created to offloading the affected part of the ankle.

This can be an effective treatment for early arthritis of the ankle and may preserve the patients own ankle joint for many years prior to requiring ankle replacement or ankle fusion surgery.

Alajlan A, Santini S, Alsayel F, Teoh KH, Alharbi W, Puls L, et al. Joint-Preserving Surgery in Varus Ankle Osteoarthritis. JCM. 2022 Apr 14;11(8):2194.

Figure 1: realignment osteotomy to correct arthritis in the outside (lateral) part of the ankle joint

Figure 2: realignment surgery for a patient with varus (medial/inside) early osteoarthritis of the ankle

Post-operative plan:

  • Surgery is typically a 1-2 night stay

  • A nerve block of the leg is administered to help with pain

  • 0-2 weeks: elevation at home, plaster cast

  • 2-6 weeks: partial weight bearing in a CAMboot

  • 6-10 weeks onwards: full weight bearing in moon boot

  • >12 weeks: progress to strengthening

Download post-operative care guide

Risks of surgery

  • Swelling, stiffness

  • Infection and wound breakdown

  • Blood clots

  • Scar sensitivity

  • Ongoing pain

  • Recurrence of deformity

  • Removal of plates and screws with a second operation

  • Progression to arthritis of the foot or ankle joints - this may require further surgery