TKA converted from UKA had higher revision risk vs primary TKA
Published results showed a three-fold higher risk of revision when total knee arthroplasty was converted from medial unicompartmental knee arthroplasty compared with primary total knee arthroplasty.
Anders El- Galaly , MD, and colleagues compared 1,012 TKAs converted from medial unicompartmental knee arthroplasty (UKA) with 73,819 primary TKAs and 2,572 revision TKAs from the Danish Knee Arthroplasty Registry from 1997 to 2017. Researchers considered risk of revision as the primary outcome. Researchers also analyzed the influence of different implants, the indications for UKA conversion and surgical volume on the survival of TKA converted from UKA, and compared the indications for revision.
Researchers found 85% of the converted UKAs were mobile bearing. Compared with patients with primary TKA or revision TKA, at the time of conversion, patients who received UKA were younger and more were Charnley class A, according to results. Results showed TKAs converted from UKAs had comparable survival with that of revision TKAs and were significantly inferior to the survival of primary TKAs. Researchers noted differences in conversion implants, experience with revision surgery and the indications for the UKA-to-TKA conversion did not affect the survival of TKA converted from UKA. Frequent indications for revisions of TKA converted from UKA included instability and unexplained pain, according to results.
“UKA should be regarded as a definitive treatment in line with TKA because, if it fails, the survival of a TKA converted from a UKA is comparable with the survival of a TKA revision,” El-Galaly told Healio.com/Orthopedics. – by Casey Tingle
Disclosure: El-Galaly reports no relevant financial disclosures.