Lateral ankle ligament anatomic reconstruction for chronic ankle instability: Allograft or autograft? A systematic review

BACKGROUND: To investigate if there is any evidence in favour of autograft or allograft use for anatomic reconstruction of lateral ankle ligaments in patients with symptomatic chronic ankle instability. METHODS: A literature search was performed in PubMed MEDLINE, Cochrane Library, EMBASE and Google Scholar databases, over the years 1994-2017, to identify the studies presenting clinical results of anatomic lateral ankle ligaments reconstruction using various combinations of the keywords "lateral ankle ligaments reconstruction", "anatomic reconstruction", "chronic ankle instability", "allograft", "autograft". The surgical procedure was considered anatomic if consistent with the description of lateral ankle ligaments made by Burks and Morgan in 1994. RESULTS: Among the 89 papers matching the search terms, only 12 could be included in which 357 anatomic lateral ankle ligaments reconstructions were performed. One was a comparative case series (level of evidence III - LOE III) while other papers were retrospective case series (LOE IV), the mean Modified Coleman Methodology Score (MCMS) was fair: 56.7 (SD±5.2). Due to the low level of evidence of the available literature only a qualitative analysis was performed. The limited evidence from the studies analysed suggests that there is no difference in graft survivorship, graft-dependent variables, patient's satisfaction, clinical outcome measures and radiographic results between allograft and autograft. CONCLUSIONS: Given the low number of studies, their poor methodology score and their low level of evidence it is not possible to determine if allograft is better or safer than autograft.