Ankle Arthritis

Ankle arthritis is relatively uncommon compared to hip and knee arthritis.

Ankle arthritis is most often post-traumatic that is; following an injury. Although ankle sprains are incredibly common, ankle arthritis is relatively rare, therefore we do not believe that ankle sprains in general cause arthritis.

Patients with ankle arthritis complain of pain anteriorly, this may be associated with swelling, deformity and limitation of activities particularly walking.

On examination:

• The patient may walk with a limp.
• They will generally have pain anteriorly, medially and laterally.
• The ankle joint will be stiff when compared with the opposite side.
• Generally they will have satisfactory movement in the subtalar and talonavicular joints.

Investigations:

• Plain x-rays taken weight bearing of the ankle, AP, lateral and mortise view.
• CT scanning and MRI scanning are useful.
• CT scanning will show the presence of cysts and MRI scan will show early arthritis often before it appears on plain x-rays.

Treatment options:

• Nonsurgically, ankle arthritis can be treated by weight loss, cushioning shoes and anti-inflammatory medication.
• A cortisone injection may provide transient relief.
• I am not a firm believer in PRP injections or stem cell injections.

Surgical options:

• If there is deformity and one side of the joint is preserved, an osteotomy of either the distal tibia or the calcaneus may buy the patient time.
• Whilst distracting the joint using an external fixator may provide relief, in general this technique has not been popular in this country.
• For end-stage arthritis, the options are really replacement or fusion.
• Unfortunately ankle replacement has not been as successful as hip replacement. (for example in this country in 2010 there were 450 ankle replacements performed. In 2016 there were only 130 performed. Compare this to 50,000 hip replacements and approximately 50,000 knee replacements. Whilst the Internet is replete with stories of successful ankle replacement unfortunately our experience in this country and that of our colleagues in New Zealand has not been as favourable). 
• The problems with ankle replacement include; the formation of cysts around the prosthesis which can occur very early (as early as two years). The other problem is of unexplained pain.
• Ankle fusion whilst sounding unattractive is a good option in the active patient as long as the surrounding joints are in good condition.   Many techniques of ankle fusion have been described. The procedure can be performed open or arthroscopically. Ankle fusion is however not without its problems. The surgery requires hospitalisation and a period of immobilisation of approximately 10 weeks the first six of which are nonweight bearing.   The fusion rate in most series is between 80 and 90%. Smokers are known to have an increased risk of non-union.
• The other concern with ankle fusion is that the surrounding joints will wear out prematurely. This is less of a concern if one is fusing a 75-year-old as if one is fusing a 25-year-old.   Naturally fusing the ankle does not make it normal.  Gait studies performed on patients with ankle fusion do suggest a slower cadence of gait and a shortened stride length. Nonetheless most patients with a successful ankle fusion are happy in the sense that they have less pain and better function.