The Salto Talaris XT Revision Ankle Prosthesis

Five-Year Results of the Salto XT Revision Ankle Arthroplasty

BACKGROUND

The treatment of failed ankle replacements is debated, and little is published about the medium- and long-term results of revision implants. We wanted to examine prosthesis survival and physical function at least 5 years after insertion of the Salto XT revision prosthesis.

METHODS

All consecutive patients operated with a Salto XT revision prosthesis underwent clinical and radiologic examinations preoperatively and after 3, 12, 24, and 60 months. Complications and reoperations are described, and changes in patient-reported outcome measures and clinical scores are reported.

RESULTS

Thirty patients were operated with a Salto XT revision prosthesis between March 2014 and March 2017. Three of these were revised (1 to a fusion and 2 to a new prosthesis), and 3 patients were reoperated with screw removal. A concurrent subtalar fusion was performed on 13 patients, and there was 1 case of likely nonunion after these procedures, but no reoperations. The mean AOFAS score increased from 39.2 (95% CI 30.8-47.5) preoperatively to 75.1 (95% CI 67.3-82.9) after 5 years, and the mean improvement was 34.2 points (95% CI 23.8-44.6). Mean EQ-5D increased from 0.36 (95% CI 0.30-0.42) preoperatively to 0.74 (95% CI 0.64-0.85) after 5 years, an improvement of 0.34 (95% CI 0.19-0.49). Radiolucent lines were present in all but 3 patients. Five-year prosthesis survival was 93% (83.6-100).

CONCLUSION

This is the first study to present medium-term results of this implant. We found good improvement in outcome scores and good implant survival, but also a high prevalence of radiolucent lines.

Enhanced recovery (fast-track surgery) after total ankle replacement: The state of the art

The post-operative results of a total ankle replacement are not determined solely by an optimal surgical technique, but by an appropriate anesthesiological and rehabilitative post-operative approach. Enhanced functional recovery often depends on a multidisciplinary approach based on a correct framework of the patient and his needs, requests, and characteristics. Extensive bibliographical research has been performed on Pubmed, Google Scholar, Scopus. This comprehensive and inclusive review of the literature aims to examine the state of the art of "fast-track" protocols employed in total ankle replacement (TAR), considering pre-operative preparation, anesthetic management, intraoperative and surgical factors, post-operative rehabilitative care and reduction of hospitalization time.

Post-operative management after total ankle arthroplasty: A systematic review of the literature

BACKGROUND

Currently, there is no consensus on the most appropriate post-operative management for patients undergoing total ankle arthroplasty. The aim of this study is therefore to offer a systematic review of the pertaining literature to identify current post-operative protocols and describe possible differences.

METHODS

A systematic review to identify recent studies concerning the post-operative management after total ankle arthroplasty was conducted. Five topics were analyzed: length of hospital stay, type and duration of immobilization, weight-bearing management, post-operative pharmacological therapies, adopted rehabilitation scheme.

RESULTS

Eighty-four studies met the inclusion criteria and were included in the review process. Most of the papers appear to have conflicting opinions with no consensus and homogeneous protocols.

CONCLUSION

Due to various methodological limitations, it is not possible to provide sufficiently supported evidence-based recommendations, and it is therefore difficult to determine the superiority of one post-operative protocol over the others after total ankle arthroplasty.

Polka dot cementless talar component in enhancing total ankle replacement fixation: A parametric study using the finite element analysis approach

The primary stability of a total ankle replacement (TAR) is essential in preventing long-term aseptic loosening failure and could be quantified based on micromotion at the bone-prosthesis interface subjected to physiological loading during the normal walking. A 3D finite element analysis was conducted to investigate the current commercial STAR™ Ankle TAR bone-prosthesis interface relative micromotion (BPIRM) with addition of the talus bone minimum principal bone stresses (MPBS). Comparison was made to the proposed polka dot designs with the hemispheric feature that was demonstrated to enhance BPIRM. Parametric studies were conducted on the hemispheric features with changes in its diameter, length and shape. The FE results indicated high BPIRM at the talar component was primarily contributed by de-bonding (in the normal direction) between the talus bone and talar component. The MPBS were found to be most significant in the superior anterior and superior medial regions of the talus bone. When the pin length was increased from 1.5 to 3 mm, the BPIRM was predicted to fall below 50 μm in favour of bone in-growth. Based on the practicality of the prosthesis implantation during the surgical procedure, the final design that incorporated both the initial polka dot and 3 mm pin length in a crisscross manner was deemed to be a favorable design with reduced BPIRM and MPBS hence lowering the risk of long-term aseptic loosening.

Trend in Spain in the use of total ankle arthroplasty versus arthrodesis in the period 1997-2017

OBJECTIVE

The main objective of this study is to compare proportionally the incidence of total ankle arthroplasty (TAA) versus ankle arthrodesis and to determine the variables that may have influenced its indication. The secondary objective is to analyse the trend in the use of TAA using a population-based analysis and to compare our results with those reported by national registries in other countries.

MATERIAL AND METHOD

A retrospective review of the Minimum Basic Data Set from 1997-2017 was performed. Subjects were categorised according to surgical procedure. Their temporal evolution was analysed and hospital variables associated with the indication (age, sex, hospital complexity) were identified. In order to compare the trend in Spain with respect to other countries, the information was standardised as number of procedures per 100,000 inhabitants/year and a projection was made for the five-year period 2020-2025.

RESULTS

In the period 1997-2017, 11,669 ankle arthrodesis and 1,049 TAAs were performed. The trend was increasing and significant for both procedures, however, in the last 10 years analysed the proportional trend of TAA decreased significantly. Being female (OR 1.32), being 65 years or older (OR 1.50) and being operated in a complex hospital (OR 1.31) were associated with the indication for a TAA. Compared to other countries, Spain has much lower rates of TAA utilisation, with minimal growth estimated for the year 2025.

CONCLUSION

Although the use of TAA has increased, its growth has been lower than that of ankle arthrodesis and its current trend is proportionally decreasing, with female sex, age≥65 years and the patient being operated in a medium/high complexity hospital being associated with the indication for TAA. Compared with other countries, Spain has much lower rates of use and its projection over the next five years, although increasing, is expected to be minimal.

Total Ankle Replacement Options

Total ankle arthroplasty has been in development for more than 40 years. Although early designs were experimental with high failure rates, current implants are significantly improved, showing promising functional results and clinical outcomes. Total ankle replacement designs are split into mobile-bearing and fixed-bearing designs. When deciding whether to perform ankle arthroplasty, many factors need to be considered to determine if the patient is suitable and which implant is the best fit for patient and surgeon. Many prostheses are available in the United States today and the purpose of this article is to outline options for foot and ankle surgeons.

Reliability of the Phi angle to assess rotational alignment of the talar component in total ankle replacement

BACKGROUND

The purpose of this study was to investigate the test-retest reliability of the Phi angle in patients undergoing total ankle replacement (TAR) for end stage ankle osteoarthritis (OA) to assess the rotational alignment of the talar component.

METHODS

Retrospective observational cross-sectional study of prospectively collected data. Post-operative anteroposterior radiographs of the foot of 170 patients who underwent TAR for the ankle OA were evaluated. Three physicians measured Phi on the 170 randomly sorted and anonymized radiographs on two occasions, one week apart (test and retest conditions), inter and intra-observer agreement were evaluated.

RESULTS

Test-retest reliability of Phi angle measurement was excellent for patients with Hintegra TAR (ICC=0.995; p<0.001) and Zimmer TAR (ICC=0.995; p<0.001) on radiographs of subjects with ankle OA. There were no significant differences in the reliability of the Phi angle measurement between patients with Hintegra vs. Zimmer implants (p>0.05).

CONCLUSIONS

Measurement of Phi angle on weight-bearing dorsoplantar radiograph showed an excellent reliability among orthopaedic surgeons in determining the position of the talar component in the axial plane.

LEVEL OF EVIDENCE

Level II, cross sectional study.