Aims

The purpose of this study was to determine the functional outcome and implant survivorship of mobile-bearing total ankle arthroplasty (TAA) performed by a single surgeon.

Despite advancements, revision rates following total ankle replacement (TAR) are high in comparison to other total joint replacements. This explant analysis study aimed to investigate whether there was appreciable metal particulate debris release from various contemporary TARs by describing patterns of material loss. Twenty-eight explanted TARs (9 designs: 3 fixed and 6 mobile bearing), revised for any reason, were studied. The articulating surfaces of the metal tibial and talar components as well as the polyethylene insert were assessed for damage features using light microscopy. Based on the results of the microscopic analysis, scanning electron microscopy with energy dispersive X-ray spectroscopy was performed to determine the composition of embedded debris identified, as well as non-contacting 3D profilometry. Pitting, indicative of material loss, was identified on the articulating surfaces of 54% of tibial components and 96% of talar components. Bearing constraint was not found to be a factor, with similar proportions of fixed and mobile bearing metal components showing pitting. More cobalt-chromium than titanium alloy tibial components exhibited pitting (63% versus 20%). Significantly higher average surface roughness (Sa) values were measured for pitted areas in comparison to unpitted areas of these metal components (p<0.05). Additionally, metallic embedded debris (cobalt-chromium likely due to pitting of the tibial and talar components or titanium likely from loss of their porous coatings) was identified in 18% of polyethylene inserts. The presence of hard 3. rd. body particles was also indicated by macroscopically visible sliding plane scratching, identified on 79% of talar components. This explant analysis study demonstrates that metal debris is released from the articulating surfaces and the coatings of various contemporary TARs, both fixed and mobile bearing. These findings suggest that metal debris release in TARs may be an under-recognised issue that should be considered in the study of painful or failed TAR moving forwards

Introduction. Ankle replacement is now common in the UK. In a tertiary referral NHS practice, between 1997–2011 we implanted two types of cementless mobile bearing total ankle replacements (TAR). Methods. We reviewed our operative database and electronic patient records and confirmed the number of prosthesis with our theatre records. All case notes and radiographs were reviewed. Failure was taken as revision, and patients were censored due to death or loss to follow-up. The survivorship was calculated using a life table (the Kaplan-Meier method), with 95% confidence intervals. Results. We found a total of 358 NHS patients had a TAR from Jan 1997 to April 2012 total ankle replacements; the mean follow up was 76 months. The principle indications for surgery included primary OA (n=146) and inflammatory arthritis in (n=79). Overall survival was 90.9% (94–84) at 10 years. A complication requiring revision developed in 42 ankles and 36 were revised or fused. Thirty-two TAR's underwent further hind foot fusions which were not attributed as a failure of the prosthesis. We arthroscoped 6 TAR's for hetrotrophic calcification. When we separated the implants we found the STAR (implanted from 1997–2004) had a 5-year survival of 95.2% (98–91) and the Mobility (implanted from 2004–11) of 92.6% (96–88). We found early failures (within 2 years of implantation) were higher within 2 years of introduction of TAR and on changing our prosthesis. Conclusion. In a study of TAR undertaken at one centre principally by an experienced surgeon and team, we have shown a learning curve. Cementless mobile bearing total ankle replacements (TAR) conducted on a routine basis with careful patient selection has a 90.9% survivorship over a 10-year period. The difference in survival for two implants is not statistically significant

Introduction. Traditional treatment for end-stage ankle arthritis has been ankle arthrodesis, however ankle arthroplasty is becoming an accepted alternative. The Zenith Ankle (Corin, UK) is 3rd generation implant with a mobile bearing design. In the NJR 2016 report, the Zenith was the commonest ankle prosthesis implanted in the UK. However, compared to other ankle implants, there's little published data on its performance and survival. The aim of this study was to analyse outcome in a consecutive series from a non-designer centre. Method. We conducted a retrospective review of a consecutive series of 118 Zenith Ankle replacements implanted in our Unit (December 2010 to May 2016). Data was collected from our National Joint Registry entries, research databases, patient notes, PACS and PROMS. Results. Average age was 68.2 years (range 46–46 years; 75M:43F; 97 Osteoarthritis, 20 inflammatory arthritis, 1 haemophilia). Results show a 95.8% survivorship at average 3.5 years follow up (range 0.6–6.3 years). 5 patients (4.2%) required revision. Average pre- and post-op MOXFQ scores were 85.0/100 and 32/100 respectively with improvements in VAS from 7.0/10 to 3.6/10, with an average range of movement of 20.4 degrees. Overall satisfaction rate was 89%. There were 65 complications in 55 patients, but only 7.7% of these led to detrimental effects on the implant. The commonest were malleolar fracture (14.4%), wound problems (13.6%) and superficial infection (12.7%), medial gutter pain (10.2%). There were no cases of deep infection. Five patients required revision (all were revised to revision arthroplasty), for component loosening, or pain and stiffness. Conclusions. This is largest non-designer centre series examining the outcomes of the Zenith implant. Survival figures for this implant are comparable to NJR averages (6.8% revision at 5 years), with high levels of patient functional outcome and satisfaction. The data highlights the risks associated with this procedure

Introduction:. We present the early results of 220 Rebalance Total Ankle Replacements performed in 6 centres in 4 different countries. Methods:. The Rebalance Total Ankle Replacement is a new 3 component uncemented mobile bearing prosthesis with a surface coating of ‘bonemaster’ and an ‘e’ poly bearing. The prosthesis was released in a limited way in May 2011. Since then 220 replacements have been implanted in 218 patients in 6 centres in 4 different countries (UK, Sweden, Canada, Czech Republic). All the x-rays and case notes were reviewed.63 prostheses have a minimum follow up of 2 years. Outcome measures included revision of the prosthesis, and the incidence of progressive and non-progesssive radiolucent lines around the prosthesis. Results:. 7 patients underwent revision or are awaiting revision of their prosthesis. Reasons for revision included loosening(2), infection(1), malposition(2), periprosthetic fracture(1), impingement(1). 9 patients had non-progressive radiolucent lines and 2 patients had progressive radiolucent lines. 1 patient with progressive radiolucent lines is waiting revision for suspected infection. 8 patients suffered fractures to the lateral malleolus and 4 to the medial malleolus. There were no cases of balloon osteolysis. 29 patients had pre-op AOFAS scores= 41(12–67). 21 had 1 year post-op AOFAS scores= 73.5(26–100). 12 had 2 year AOFAS scores= 75.5(50–100). Conclusion:. The early results are encouraging and we believe support its wider use

Aims

This is a multicentre, non-inventor, prospective observational study of 503 INFINITY fixed bearing total ankle arthroplasties (TAAs). We report our early experience, complications, and radiological and functional outcomes.

Aims

We report the medium-term outcomes of a consecutive series of 118 Zenith total ankle arthroplasties (TAAs) from a single, non-designer centre.

Aims

Total ankle arthroplasty (TAA) surgery is complex and attracts a wide variety of complications. The literature lacks consistency in reporting adverse events and complications. The aim of this article is to provide a comprehensive analysis of each of these complications from a literature review, and to compare them with rates from our Unit, to aid clinicians with the process of informed consent.

The purpose of this study was to evaluate the change in sagittal tibiotalar alignment after total ankle arthroplasty (TAA) for osteoarthritis and to investigate factors affecting the restoration of alignment.

This retrospective study included 119 patients (120 ankles) who underwent three component TAA using the Hintegra prosthesis. A total of 63 ankles had anterior displacement of the talus before surgery (group A), 49 had alignment in the normal range (group B), and eight had posterior displacement of the talus (group C). Ankles in group A were further sub-divided into those in whom normal alignment was restored following TAA (41 ankles) and those with persistent displacement (22 ankles). Radiographic and clinical results were assessed.

Pre-operatively, the alignment in group A was significantly more varus than that in group B, and the posterior slope of the tibial plafond was greater (p < 0.01 in both cases). The posterior slope of the tibial component was strongly associated with restoration of alignment: ankles in which the alignment was restored had significantly less posterior slope (p < 0.001).

An anteriorly translated talus was restored to a normal position after TAA in most patients. We suggest that surgeons performing TAA using the Hintegra prosthesis should aim to insert the tibial component at close to 90° relative to the axis of the tibia, hence reducing posterior soft-tissue tension and allowing restoration of normal tibiotalar alignment following surgery.

Cite this article: Bone Joint J 2015;97-B:1525–32.

Between 2002 and 2008, 130 consecutive ankles were replaced with an hydroxyapatite (HA) and titanium-HA-coated Ankle Evolutive System total ankle prosthesis. Plain radiographs were analysed by two independent observers. Osteolytic lesions were classified by their size and location, with cavities > 10 mm in diameter considered to be ‘marked’. CT scanning was undertaken in all patients with marked osteolysis seen on the plain radiographs.

Osteolytic lesions were seen on the plain films in 48 (37%) and marked lesions in 27 (21%) ankles. The risk for osteolysis was found to be 3.1 (95% confidence interval 1.6 to 5.9) times higher with implants with Ti-HA porous coating.

Care should be taken with ankle arthroplasty until more is known about the reasons for these severe osteolyses.

We report the clinical and radiological outcome of total ankle replacement performed in conjunction with hindfoot fusion or in isolation. Between May 2003 and June 2008, 60 ankles were treated with total ankle replacement with either subtalar or triple fusion, and the results were compared with a control group of 288 ankles treated with total ankle replacement alone.

After the mean follow-up of 39.5 months (12 to 73), the ankles with hindfoot fusion showed significant improvement in the mean visual analogue score for pain (p < 0.001), the mean American Orthopaedic Foot and Ankle Society score (p < 0.001), and the mean of a modified version of this score (p < 0.001). The mean visual analogue pain score (p = 0.304) and mean modified American Orthopaedic Foot and Ankle Society score (p = 0.119) were not significantly different between the hindfoot fusion and the control groups. However, the hindfoot fusion group had a significantly lower mean range of movement (p = 0.009) and a higher rate of posterior focal osteolysis (p = 0.04). Both groups showed various complications (p = 0.131) and failure occurring at a similar rate (p = 0.685).

Subtalar or triple fusion is feasible and has minimal adverse effects on ankles treated with total ankle replacement up to midterm follow-up. The clinical outcome of total ankle replacement when combined with hindfoot fusion is comparable to that of ankle replacement alone. Thus, hindfoot fusion should be performed in conjunction with total ankle replacement when indicated.

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.