Robotic-Assisted and Computer-Navigated Unicompartmental Knee Arthroplasties: A Systematic Review.

INTRODUCTION: Unicompartmental knee arthroplasty (UKA) effectively improves pain and function associated with isolated compartmental knee arthritis. The developments of computer-navigated and robotic-assisted UKA are among the most significant changes that have improved patient outcomes. This study aimed to systematically review the literature to identify differences between computer-navigated and robotic-assisted UKAs. MATERIALS AND METHODS: Twenty total articles were identified. Data pertaining to demographics, outcomes, and complications/failures were extracted from each study. Reoperation/revision rates, indications for reoperation/revision, type of procedure, and number of patients who underwent conversion to TKA (when available) were recorded. RESULTS: Nine studies reported 451 computer-navigated medial UKAs, with 19 (3.9%) reportedly requiring reoperation: primary revision (n=8; 42.1%), conversion to TKA (n=6), and manipulation under anesthesia (n=5). Eleven studies reported 2,311 robotic-assisted UKAs (74 lateral UKAs), with 106 (5.0%) requiring reoperation: conversion to TKA (n=46; 43.4%), primary revision (n=43), reoperations without component-removal (n=15), subchondroplasty, and partial meniscectomy/synovectomy (both n=1). Reoperation rate discrepancy between computer-navigated and robotic-assisted UKA was not statistically significant (p=0.495); age and BMI differed between both groups (p<0.0001). DISCUSSION: This study represents the first known comparison of revision rates of computer-navigated and robotic-assisted UKA, suggesting that these methods can benefit orthopaedic surgeons, especially those new to UKA or in a low-volume practice.