ISAKOS: 2019 Congress in Cancun, Mexico

2019 ISAKOS Biennial Congress Paper #156


Survivorship and Functional Outcomes of Robotic-Assisted Medial Unicompartmental Knee Arthroplasty: A Minimum of 5-Year Follow-Up

Keerati Chareancholvanich, MD, Bangkok THAILAND
Chaturong Pornrattanamaneewong, MD, Bangkok THAILAND
Suphawat Tantithawornwat, MD, Bangkok THAILAND
Areesak Chotivichit, MD, Bangkok THAILAND
Rapeepat Narkbunnam, MD, Bangkok THAILAND
Aasis Unnanuntana, MD, MSc, Bangkok THAILAND
Vatanachai Rojvanit, MD, Bangkok THAILAND
Pakpoom Ruangsomboon, MD, Bangkok THAILAND
Pacharapol Udomkiat, MD, Bangkok THAILAND

Siriraj Hospital, Mahidol University, Bangkok, THAILAND

FDA Status Cleared


The revision rate of robotic-assisted UKA was high. The midterm survivorship was only 89.4%.



Robotic-assisted orthopaedic surgery has increased significantly over the past 10 years. Robotic-assisted unicompartmental knee arthroplasty (UKA) has been claimed to improve implant positioning, ligament balance and limb alignment. In 2012, we performed the first robotic-assisted UKA series in Southeast Asia. This prospective cohort study was aimed to assess the survivorship and functional outcomes of robotic-assisted UKA.


Between November 2012 and January 2013, a total of 40 consecutive patients (49 knees) who underwent robotic-assisted medial UKA (Makoplasty) in our institute were recruited. All patients received the fixed-bearing implants (Restoris) with metal-backed onlay tibial tray. The survivorship, functional outcomes and satisfaction score were recorded at a minimum of 5-year follow-up. The revision for any reasons was defined as the end point.


The mean age of patient was 71.5±6.0 years. Majority of the patients was female (77.6%) with an average BMI of 25.0±3.2 kg/m2. At 5 years, 2 patients had lost to follow up. Thus, a total of 47 knees were finally analyzed. In this series, 5 patients required the revision surgery (1 periprosthetic joint infection, 1 tibial component subsidence, 1 medial tibial plateau fracture and 2 aseptic femoral component loosening). Therefore, the survivorship at 5 years was 89.4%. Of the remaining patients without revision, Oxford knee score was significantly improvement when compared to preoperative status (p < 0.05). The mean satisfaction Likert scale was 4.24 points. 82.8% of the patients had very satisfied or satisfied score with their knee function.


In our study, the revision rate of robotic-assisted UKA was high. The midterm survivorship was only 89.4%. We recommended closed follow-up of patient and aware the potential complications. However, the larger and long term study was required.