AVN & Prosthetic Replacement of the Talus
Avascular necrosis of the talus has been a diagnosis vexing foot-and-ankle surgeons for a long time. Real pain and disability with treatment options have often been lacking. Let's take a deeper look at the data to see if we can get on board the total talus replacement (TTR) bandwagon.
TAA and TTR
In a level 4 series, Kanzaki et al. reported on TAA with total talar replacement in 22 patients with indications for combined TAA/TTR being osteoarthritis (18), rheumatoid arthritis (three), and talar osteonecrosis with osteoarthritis (one). The authors reported a range of motion between 26.6 and 46.5 degrees at mean follow-up time of 34.9 months. The Japanese Society for Surgery of the Foot (JSSF) scale improved across all domains, including pain and function. There was prolonged wound healing in three patients, and medial malleolus fracture in four patients.
Longer term results with talar body prosthesis
With talus AVN as the indication Thos Harnrrongroj reported on 36 talar body prostheses without TAR. The duration of follow-up was 10 to 36 years. The AOFAS ankle-hindfoot score did not differ significantly based on length of follow-up. Early prosthesis failure occurred in five patients due to size mismatch (two), tumor recurrence (one), infection (one), and osteonecrosis of the talar head and neck (one). These failures, which occurred at 8 to57 months, were treated with tibiotalar arthrodesis in three patients, prosthesis revision in one, and below-the-knee amputation in one.
Players in the US
Restor3d, 4Web Medical, and Paragon 28 with its acquisition of Additive Orthopedics are players in the US. Look for additional strategic alliances and new materials shortly.