AKILE™ total ankle arthroplasty: Clinical and CT scan analysis of periprosthetic cysts

• Published in: Orthopaedics & traumatology, surgery & research surgery & research, 2014-12, Vol.100 (8), p.907-915
• Main Authors: Lucas y Hernandez, J, Laffenêtre, O, Toullec, E, Darcel, V, Chauveaux, D
• Format: Article
• Language: English
• Subjects: Adult; Aged; Ankle Joint - diagnostic imaging; Ankle Joint - surgery; Arthroplasty; Arthroplasty, Replacement, Ankle; Cysts - diagnostic imaging; Female; Humans; Joint Prosthesis; Male; Middle Aged; Orthopedics; Osteolysis; Osteolysis - diagnostic imaging; Range of Motion, Articular; Retrospective Studies; Surgery; Survivorship; Tomography, X-Ray Computed; Total ankle replacement
• ISSN: 1877-0568; 1877-0568
• DOI: 10.1016/j.otsr.2014.09.019

Abstract Introduction Despite good clinical results following total ankle replacement (TAR), the development of large periprosthetic cysts (> 400 mm2 ) in the medium-term is a source of concern. Objective The primary objective of this study was to detect any large periprosthetic cysts in a cohort of AKILE™ patients using radiographs and CT scans, and then to compare these findings to published ones. Material and methods A total of 127 TAR procedures were performed between June 1995 and January 2012. We retrospectively reviewed 68 cases with the newest AKILE™ implant design that had a minimum follow-up of 36 months. The average follow-up was 81 ± 33 months; eight patients were lost to follow-up. The outcomes consisted of analyzing radiographs (A/P and lateral weight bearing views, Meary view and lateral views of flexion/extension) and helical CT scans, performing clinical evaluations (range of motion, AOFAS score, Foot Function Index, pain levels) and determining the survivorship of TAR implants. Results TAR survival at 5 years was 79% for in situ implants and 62% for revision-free implants. The AOFAS score improved from 33.7 ± 14.7 to 77.1 ± 15.1 (out of 100) and the pain sub-score was 30.2 ± 9.7 (out of 40) at the last follow-up. The average ankle range of motion was 32.3° ± 12.7° on the radiographs. CT scan revealed Type A cysts (< 200 mm2 ) under the talar implant in 52% of cases and in the tibia in 50% of cases; these cysts were smaller than 100 mm2 in 80% of cases and had no effect on the implants. No periprosthetic cysts larger than 400 mm2 in size were identified. Discussion The medium-term functional results and survivorship are comparable to those reported for other TAR designs. The incidence of cysts was low overall and there were no large-diameter cysts, which should improve long-term survival. The implant's design and materials likely played a role in preserving the periprosthetic bone stock. The AKILE™ TAR has distinctive features related to the low rate of large periprosthetic cysts in the medium-term. Level of evidence IV (retrospective case series).