Medial Ankle Impingement
By James A. Nunley II, M.D.
A 59-year-old female presented with ankle pain. She had a closed tibia and fibula fracture in 1983 that was treated with the “pins in plaster” technique. Because of increasing ankle pain, she had an anterior arthrotomy and ankle debridement in 2003. This procedure provided temporary relief of pain, however, pain returned and then increased. She elected to undergo a STAR™ replacement procedure in February 2010.
AP and lateral radiographs showed good overall alignment and symmetric loss of joint space.
The arrow in Figure 5 points to area of bone that should have been removed.
The patient’s post-operative course was uneventful. She began walking at 3 weeks post op and was fully weight bearing at 6 weeks.
However, by 6 months post op, she began experiencing medial ankle pain. The pain was treated with NSAIDs and rest, but still persisted.
At 12 months post op, she continued to have medial ankle pain, worse with ambulation. There was localized tenderness in and around the medial malleolus.
The initial question was: What was causing the pain? There were no signs of infection, her range of motion was dorsiflexion to 5 and plantar flexion to 30. The posterior tibial tendon was strong. There was no limp, but the entire medial malleolus was tender to deep palpation.
I obtained a CT scan to look for loosening of the prosthesis or possible stress fractures.
The CT scan shows a well fixed prosthesis and no evidence of a stress fracture, so I decided that the pain was medial gutter impingement and we returned to the operating room for debridement.
I elected a new incision medial to the old arthrotomy. As you can see from the pictures and video below, there was bony impingement from the anterior medial talus onto the medial malleolus.
Medial Ankle Impingement Video
Post-operatively, the patient’s wound healed, she returned to all activities, and her pain is gone.
In retrospect, if you examine the intra-operative fluoroscopic images, the bone that was found impinging was present on the images. After making the medial and lateral chamfer cuts on the datum, I find that sometimes there is bone anterior to the medial chamfer which can impinge in maximum dorsiflexion.
The lessons to be learned are:
1. Always check for impingement at the conclusion of the total ankle surgery, especially with maximum dorsiflexion.
2. Medial ankle pain post operatively may be from many causes, so investigate thoroughly.
3. Medial ankle debridement can produce very satisfying results.