Efficacy of total ankle replacement with meniscal-bearing devices: a systematic review and meta-analysis.
BACKGROUND
The reputation of total ankle arthroplasty for treating end-stage ankle arthritis of different origin is dubious. Newer generation meniscal-bearing prostheses may have overcome the known problems with earlier implants. There is, however, no systematic approach to the available scientific evidence allowing for a critical appraisal of their benefits and risks.


METHODS
We conducted a systematic review meta-analysis of studies exploring the efficacy of three-component total ankle prostheses. We demanded a minimum sample size of 20 subjects, at least 1 year of follow-up, and a clinically relevant study endpoint (for example, results of ankle scoring, ranges of motion [ROM], complications, and survival rates). We identified citations by electronic medical databases and a manual search. We made no restrictions for language. We used an eight-point quality scale to appraise methodological standards, and modeled outcomes by random-effects meta-regression analysis.


RESULTS
Eighteen of 1830 citations including 1086 patients fulfilled our eligibility criteria. Studies met a median of four quality items (interquartile range 2-5). Outcome estimates did not depend on methodological quality. There was no evidence of strong heterogeneity or publication bias. With standardized 100-point ankle and hindfoot scores, formal data pooling was possible for 10 trials (n =497), showing a mean improvement of 45.2 points (95% confidence interval [CI] 39.3-51.1). Overall ROM improved slightly (6.3 degrees, 95%CI 2.2-10.5 degrees ). Weighted complication rates ranged from 1.6% (deep infections) to 14.7% (impingement). Secondary surgery had to be performed in 12.5%, whereas secondary arthrodesis was necessary in 6.3%. The weighted 5-year prosthesis survival rate averaged 90.6%.


CONCLUSIONS
Ankle arthroplasty improves pain and joint mobility in end-stage ankle arthritis. Its performance in comparison to the current reference standard (that is, ankle fusion) remains to be defined in a properly designed randomized trial.
Stengel
Dirk
D
Department of Orthopaedic and Trauma Surgery, Ernst Moritz Arndt University, Friedrich Loeffler Str. 23b, 17489, Greifswald, Germany. dirk.stengel@ukb.de
Bauwens
Kai
K
Ekkernkamp
Axel
A
Cramer
Jörg
J
D000843:Ankle Joint; D018771:Arthralgia / Q000209:etiology; D001168:Arthritis / Q000150:complications / Q000601:surgery*; D019643:Arthroplasty, Replacement; D006801:Humans; D011183:Postoperative Complications; D016059:Range of Motion, Articular; D012306:Risk; D016896:Treatment Outcome