Outcomes of Primary Total Knee Arthroplasty in Patients With Ehlers-Danlos Syndromes.

BACKGROUND: Ehlers-Danlos syndromes (EDS) are connective tissue disorders that cause defects in collagen synthesis or processing, resulting in joint hypermobility. Following total knee arthroplasty (TKA), concern exists that hypermobility will affect the outcome as prosthesis relies on soft tissues for stability. The purpose of this study is to investigate the outcome of TKA in the setting of EDS compared to patients undergoing TKA for osteoarthritis (OA). METHODS: We identified 16 patients (20 knees) with EDS who underwent a TKA between 2001 and 2016. Patients were matched 1:2 (n = 40) on age, gender, body mass index, and surgical date to patients undergoing TKA for OA. RESULTS: We found no difference in age, body mass index, or follow-up between the cohorts (P > .05). EDS patients had significantly more surgical interventions prior to TKA (P = .03) and were more likely to require constrained components (x2 = 0.002). Following TKA, 4 patients in the EDS group and 9 patients in the matched cohort underwent a reoperation for any reason including 1 revision in the EDS cohort and 3 in the OA cohort. We found no significant difference in reoperation or revision rates between the cohorts (P > .05). There was no difference in Knee Society Scores between groups at last follow-up (P = .63) or radiographic evidence of loosening. CONCLUSION: Although patients with EDS were more likely to require a constrained component, they are not at increased risk of revision or reoperation following TKA in the intermediate term.