Aims

The Vantage Total Ankle System is a fourth-generation low-profile fixed-bearing implant that has been available since 2016. We aimed to describe our early experience with this implant.

We performed a retrospective review of a consecutive series of 178 Mobility total ankle replacements (TARs) performed by three surgeons between January 2004 and June 2009, and analysed radiological parameters and clinical outcomes in a subgroup of 129 patients. The mean follow-up was 4 years (2 to 6.3). A total of ten revision procedures (5.6%) were undertaken. The mean Ankle Osteoarthritis Scale (AOS) pain score was 17 (0 to 88) and 86% of patients were clinically improved at follow-up. However, 18 patients (18 TARs, 14%) had a poor outcome with an AOS pain score of > 30. A worse outcome was associated with a pre-operative diagnosis of post-traumatic degenerative arthritis. However, no pre- or post-operative radiological parameters were significantly associated with a poor outcome. Of the patients with persistent pain, eight had predominantly medial-sided pain. Thirty TARs (29%) had a radiolucency in at least one zone.

The outcome of the Mobility TAR at a mean of four years is satisfactory in > 85% of patients. However, there is a significant incidence of persistent pain, particularly on the medial side, for which we were unable to establish a cause.

Cite this article: Bone Joint J 2013;95-B:1366–71.

In a retrospective study we compared 32 HINTEGRA total ankle replacements (TARs) and 35 Mobility TARs performed between July 2005 and May 2010, with a minimum follow-up of two years. The mean follow-up for the HINTEGRA group was 53 months (24 to 76) and for the Mobility group was 34 months (24 to 45). All procedures were performed by a single surgeon.

There was no significant difference between the two groups with regard to the mean AOFAS score, visual analogue score for pain or range of movement of the ankle at the latest follow-up. Most radiological measurements did not differ significantly between the two groups. However, the most common grade of heterotopic ossification (HO) was grade 3 in the HINTEGRA group (10 of 13 TARs, 76.9%) and grade 2 in the Mobility group (four of seven TARs, 57.1%) (p = 0.025). Although HO was more frequent in the HINTEGRA group (40.6%) than in the Mobility group (20.0%), this was not statistically significant (p = 0.065).The difference in peri-operative complications between the two groups was not significant, but intra-operative medial malleolar fractures occurred in four (11.4%) in the Mobility group; four (12.5%) in the HINTEGRA group and one TAR (2.9%) in the Mobility group failed (p = 0.185).

Cite this article: Bone Joint J 2013;95-B:1075–82.

The Bologna–Oxford (BOX) total ankle replacement (TAR) was developed with the aim of achieving satisfactory pain-free movement of the ankle. To date, only one single multicentre study has reported its clinical results. The aim of this study was to conduct an independent review of its mid-term results.

We retrospectively reviewed a total of 60 prospectively followed patients in whom 62 BOX TARs had been implanted between 2004 and 2008. We used the American Orthopedic Foot and Ankle Society (AOFAS) score to assess the clinical results. Standardised radiographs taken at the time of final follow-up were analysed by two observers. The overall survival was 91.9% at a mean follow-up of 42.5 months (24 to 71). The mean AOFAS score had improved from 35.1 points (sd 16.6; 4 to 73) pre-operatively to 78.0 (sd 10.7; 57 to 100) at final follow-up (p < 0.01). Tibial radiolucencies < 2 mm in width were seen around 16 TARs. Talar radiolucencies < 2 mm were seen around four TARs. A total of 47 patients (78.3%) were very satisfied or satisfied with the outcome. Five patients required revision for functional limitation or continuing pain.

We describe the results of a randomised, prospective study of 200 ankle replacements carried out between March 2000 and July 2003 at a single centre to compare the Buechel-Pappas (BP) and the Scandinavian Total Ankle Replacement (STAR) implant with a minimum follow-up of 36 months. The two prostheses were similar in design consisting of three components with a meniscal polyethylene bearing which was highly congruent on its planar tibial surface and on its curved talar surface. However, the designs were markedly different with respect to the geometry of the articular surface of the talus and its overall shape.

A total of 16 ankles (18%) was revised, of which 12 were from the BP group and four of the STAR group. The six-year survivorship of the BP design was 79% (95% confidence interval (CI) 63.4 to 88.5 and of the STAR 95% (95% CI 87.2 to 98.1). The difference did not reach statistical significance (p = 0.09). However, varus or valgus deformity before surgery did have a significant effect) (p = 0.02) on survivorship in both groups, with the likelihood of revision being directly proportional to the size of the angular deformity. Our findings support previous studies which suggested that total ankle replacement should be undertaken with extreme caution in the presence of marked varus or valgus deformity.

We describe the medium-term results of a prospective study of 200 total ankle replacements at a single-centre using the Scandinavian Total Ankle Replacement. A total of 24 ankles (12%) have been revised, 20 by fusion and four by further replacement and 27 patients (33 ankles) have died. All the surviving patients were seen at a minimum of five years after operation. The five-year survival was 93.3% (95% confidence interval (CI) 89.8 to 96.8) and the ten-year survival 80.3% (95% CI 71.0 to 89.6).

Anterior subluxation of the talus, often seen on the lateral radiograph in osteoarthritic ankles, was corrected and, in most instances, the anatomical alignment was restored by total ankle replacement. The orientation of the tibial component, as seen on the lateral radiograph, also affects the position of the talus and if not correct can hold the talus in an abnormal anterior position. Subtalar arthritis may continue to progress after total ankle replacement. Our results are similar to those published previously.