Intermediate-Term Follow-Up After Ankle Distraction for Treatment of End-Stage Osteoarthritis

SLR - June 2015 - Aaron Utterback

Reference: Nguyen MP, Pedersen DR, Gao Y, Saltzman CL, Amendola A. Intermediate-term follow-up after ankle distraction for treatment of end-stage osteoarthritis. J Bone Joint Surg Am. 2015 Apr 1;97(7):590 -6

Scientific Literature Review

Reviewed By: Aaron Utterback, DPM
Residency Program: Southern Arizona VA Health Care System, Tucson, AZ

Podiatric Relevance: Ankle osteoarthritis is a debilitating condition with increasing prevalence and current estimates in the U.S. suggest that there are more than 50,000 new cases annually. The consequences of ankle osteoarthritis may include poor ankle function. Ankle arthrodesis has been considered the gold standard surgical treatment option for end stage ankle osteoarthritis because of its fairly predictable results. However, it can also lead to alterations in gait, loss of function, and adjacent joint arthritis. Ankle distraction is a way to treat symptoms while keeping arthrodesis and total ankle arthroplasty as viable options if the distraction ultimately fails.

Methods: Thirty-six patients underwent ankle distraction surgery between December 2002 and October 2006 in a prospective clinical trial. Inclusion criteria included symptomatic isolated, unilateral ankle osteoarthritis, skeletal maturity and an age no greater than sixty years old;  failure of more than a year of nonsurgical treatment, including three months of continuous treatment with nonsteroidal anti-inflammatory drugs and three months of unloading treatment; and an ability to maintain the extremity non-weight-bearing by using ambulatory aids. Patients were randomized into two arms of treatment: fixed distraction and motion distraction. A history was recorded and a physical examination was performed including evaluation of standing alignment and the range of motion of both ankles and subtalar joints. Each patient independently completed the self-assessment Ankle Osteoarthritis Scale (AOS) and the Medical Outcomes Study 36-Item Short-Form Health Survey. Radiographs as well as computed tomography and magnetic resonance imaging scans were obtained at the follow-up visits.

Results: Twenty-nine patients (81 two to four) were followed for a minimum of five years (mean, 8.3 ± 2.2 years). Sixteen (55 two to four) of the twenty-nine patients still had the native ankle joint whereas thirteen patients (45 two to four) had undergone either ankle arthrodesis or total ankle arthroplasty. Positive predictors of ankle survival included a better AOS score at two years, older age at surgery, and fixed distraction. Radiographs and advanced imaging revealed progression of ankle osteoarthritis at the time of final follow-up.       

Conclusions: Ankle function following joint distraction likely declines over time. Patients should be well informed prior to surgery of the likelihood of eventually needing a joint destructive procedure. Ankle distraction surgery should be recommended only for patients who demonstrate a willingness to follow instructions and can return for treatment if failure occurs.