THE FOLLOWING ARE POSTER PRESENTATIONS THE EARLY RESULTS OF THE MOBILITY TOTAL ANKLE REPLACEMENT

Abstract

Outcomes following total ankle replacement (TAR) have been less favorable than hip and knee arthroplasty. The Mobility TAR is a newly introduced mobile bearing ankle prosthesis which, unlike its predecessor the Agility, does not require fusion of the tibiofibular syndesmosis which in theory should reduce the rate of early failure. No studies have been published yet reporting follow-up longer than 1 year after surgery with this prosthesis.

From June 2006 to May 2008, 50 Mobility TARs were performed in our unit. Data have been collected prospectively on all 50 patients and all have been reviewed annually since surgery. Follow up ranges from one to three years.

The mean age was 65 (range 35–79). 20 patients (40%) were male. 10 underwent additional concurrent procedures (six calcaneal osteotomies, one 1st metatarsal osteotomy, two lateral ligament reconstructions, one subtalar arthrodesis). There was one early wound breakdown which subsequently healed without causing deep infection. There were no malleolar fractures. In two prostheses the talar component has subsided over two years resulting in painful loosening. Interestingly both these patients had postraumatic osteoarthritis with a fibular malunion. Both have been listed for revision to arthrodesis. One further patient has a loose talar component without subsidence and is awaiting exploration with a view to revision. There was one deep infection presenting at 18 months. One further patient reports continued hindfoot pain, thought to be from the subtalar joint and is being worked up for arthrodesis. The mean American Orthopaedic Foot and Ankle Society scores (scale 10–100) increased from 30 to 69 scores following surgery.

TAR using the Mobility prosthesis gives good early clinical results. Further follow-up studies are required to see if this performance is maintained in the long term.