INBONE Total Ankle Replacement: Current Status

Authors: James K. DeOrio, MD

Journal:  AAOS OrthoPortal

Abstract:  The INBONE Total Ankle (Wright Medical Technology, Arlington, TN) replacement is a modular ankle replacement system consisting of an intramedullary stem whose pieces are inserted through the ankle and pushed up into the tibia to support the tibial tray of the device. The original talar component of the INBONE ankle is a saddle-shaped prosthesis that resurfaces only the top of the talus. A new talar design feature of the INBONE II ankle is a sulcus and two anterior prongs. Between the tibial and talar components of the INBONE, each consisting of a cobalt-chrome alloy, lies an ultra-high–molecular-weight polyethylene spacer locked into the tibial baseplate. In the INBONE II ankle, this polyethylene component is V shaped, to fit into the talar component of the prosthesis. This article describes the use of the INBONE ankle in total ankle arthroplasty and provides a detailed review of the surgical technique used for its achievement.

Keywords:  Total ankle arthroplasty, ankle replacement system, INBONE

Current Concepts Review: Results of Total Ankle Arthroplasty

Authors: Mark E. Easley, MD; Samuel B. Adams, MD; W. Chad Hembree, MD; James K. DeOrio, MD

Journal: J Bone Joint Surg Am. 2011; 93: 1455-1468

Most published reports related to total ankle arthroplasty have a fair to poor-quality level of evidence.

Comparative studies with a fair to good-quality level of evidence suggest that total ankle arthroplasty provides equal pain relief and possibly improved function compared with ankle arthrodesis.

On the basis of the current literature, survivorship of total ankle arthroplasty implants, when measured as the retention of metal components, ranges from 70% to 98% at three to six years and from 80% to 95% at eight to twelve years.

Several investigators have argued that, in the evolution of total ankle arthroplasty, some obligatory reoperation without removal of the metal implants is anticipated; examples of reoperation include relief of osseous or soft-tissue impingement, improvement of alignment or stability of the foot and ankle, bone-grafting for cystic lesions, and/or polyethylene exchange.

A successful return to low-impact, recreational sporting activities is possible after total ankle arthroplasty.

Key words: N/A

STAR™ Ankle: Long-Term Results

Jeffrey A. Mann, MD; Roger A. Mann, MD; Eric Horton, MD

Foot & Ankle International: May 2011 (Vol.32 #5) May 1, 2011

There has been a resurgence of interest in total ankle replacement

(TAR) due to improved results with newer prostheses. However, long-term

survivorship data has been limited. The STAR™ Ankle prosthesis is the

first three-part prosthesis approved for use in the United States.

Materials and Methods: Eighty-four total ankle replacements were

performed in 80 patients using the STAR™ Ankle prosthesis and followed

prospectively. Postoperatively, patients were evaluated with the AOFAS

score for pain and function, and serial radiographs were evaluated for

stability and alignment of the prosthesis. Implant failure, secondary

procedures, and complications were recorded. Results: Ninety-one

percent of prostheses remain implanted at an average followup of 9.1

years. The probability of implant survival was 96% at 5 years and 90%

at 10 years. An average 39-point improvement in the AOFAS

ankle-hindfoot score was noted, from a mean of 43 to a mean of 82

points. We noted a statistically significant increase in both average

pain and function sub-scores. Postoperative range of motion averaged

4.5 degrees of dorsiflexion and 35 degrees of plantarflexion. Ninetytwo

percent of the patients were satisfied with their outcome. Ten patients

(13%) developed concerning osteolytic lesions. Change in prosthetic

alignment and adjacent joint arthritis were similar to previous

reports. We report 21 complications, which included 14 additional

surgical procedures. Conclusion: The first U.S. prospective long-term

survivorship data with the STAR™ Ankle prosthesis found it to be an

excellent long-term option for the treatment of ankle arthritis.

Level of Evidence: IV, Case Series

Key Words: Ankle Arthroplasty; Ankle Arthritis; Scandinavian Total

Ankle Replacement; STAR Ankle  

Find out more about the SBI: Star Ankle Implant and all other current options for TAR / Ankle Joint Implant at www.footandanklefixation.com